Let's see what we can do.....

[Cal]

Ok, purchased this Friday night in Adelaide off gumtree, $180. It is a ledacraft dc2200. We all know the specs that companies put on these things are exaggerated, supposedly 3hp with a 10amp plug! Pulled the cover off and measured the blower diameter at 12". So what do I have?

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https://uploads.tapatalk-cdn.com/20170514/d597ef94ab28660653e163bb1dd7fb37.jpg


The shed is a 6x4 meter with 3 meter gable roof, roller door at a 4 meter end and a PA door a meter in from the corner of a 6 meter wall. Plan is to sit the dusty outside in its own shed. I have about a meter of room between the shed an fence line on the back (4m)and side 6m) of the shed. The side (6m) of the shed with PA door faces the house.

https://uploads.tapatalk-cdn.com/20170514/6b3d0de2b4296f78a3585c404c67c3d4.jpg

https://uploads.tapatalk-cdn.com/20170514/aa5314c1cc9b1805c3b9e82f64643780.jpg

I have a lathe, large belt sander, mitre saw, small thicknesser, tablesaw, router table, drill press and an assortment of hand power tools.

I don't have any measuring devices for flow etc. The layout of the shed and machines is somewhat movable aside from 5.5 meters of bench along the right side of the shed on which the mitre saw sits in the middle.

Advice greatly appreciated. I have no problem with modifying the dc to improve things. I have read through a lot of the posts. Aware of using 6" ducting and so forth.

Cheers Cal

[elanjacobs]

We all know the specs that companies put on these things are exaggerated, supposedly 3hp with a 10amp plug!
Where's the problem with that?

[MandJ]

Good price considering. It's interesting in that these various units look the same on the outside but are configured differently. If you look at the pictures I posted of mine you will note that the motor is rated @ 15A 240V and has a 15A plug and drives a bigger impeller. It would be interesting to see current consumption with the intake open on this unit. I'm wondering how the fan blades are shaped in a 12" impeller, could be one of the reasons for vastly differing noise levels between these units with different size impellers ranging from 12" to 14".

A smaller lower mass impeller could be how they get away with a 10A plug, startup current would still be relatively high though, are you sure someone hasn't just swapped the plug over for a 10A?

EDIT Looking at the pic it looks like a molded plug, either the lead was replaced or it's OEM and a light aggressive blade on a 12" is getting close to 3HP but with some extra noise to go with it, then we get into the area of fan curves. I guess as usual run one extraction point at a time, 150mm ducting and open up the machines ports. Look forward to see how it goes.

[Cal]

After seeing the post on your machine I was hoping this would have a 14" impeller MandJ, but it wasn't the case. I don't have any way of measuring the startup amp draw. May have to buy an ameter.

As for the plug, when I got it home I realised that the previous owner had bypassed the no volt switch. Opened up the box and so was the case. That is all better now. It maybe the case that the whole lead was replaced but I doubt it. You're suggestion about the impeller may be correct.

Are you planning on redesigning yours without the "y" piece? I was thinking if this only has a 12" impeller, would one bag be enough? With no means to measure air volume it is a bit of an unknown.

I think I'm starting to answer my own questions in my head, buy the tools to do the job.

[Cal]

Where's the problem with that?

The problem is, it's not going to be a true 3hp motor (which I already knew) drops the speed of the impeller down and also the size. It is never going to draw the volume of air that the manufacturer claims thus making the less knowledgeable believe that they are protecting their health by just banging a 4" or 6" hose on it and jobs done. It could almost be a case for a class action against all of the distributors and manufacturers of these units. It is people's health there dealing with.

Good question by the way [emoji1]

[mannum3]

240 volts 9.6 amps best part of 2,300watts @ 750W per 1HP adds up to close to 3Hp.

Cheers Barry

[mannum3]

Volume of air quoted as 2200 cfm would be as tested, no restrictions.

Only having one bag would increase the restrictions as opposed to two bags.

Cheers Barry

[Cal]

240 volts 9.6 amps best part of 2,300watts @ 750W per 1HP adds up to close to 3Hp.

Cheers Barry

Thanks for the correction Barry! Without an ameter, I am unable to verify that this unit is the claimed 3hp or 2200watt as stated on the sticker or motor. It may well be?

[BobL]

Why won't it be a 3HP motor?

240V x 9.6 A = 2304W = 3.1HP

OK, that's input power and output power will be slightly less to take motor efficiency into account.

The numbers on the sides of motors are nominal anyway. I have measured the output HP of several dozen motors - including cheap ones on DCs and none have been below spec
The 10A plug means nothing.

The problem (if there is one) is not the motor but the small impeller. size as this will affect the impeller curve.
But the only way you will slow down the speed or any motor is to put a too high a load on it but a 12" standard impeller is actually not too high a load on a 3HP motor so it should still spin at full RPM
To slow down a 3HP motor you would have to put a larger impeller on it.

I reckon that DC as is will serve a 6x4 shed reasonably well.

Recommendations
1) The only thing I would do to that DC initially is install a reverse Bell mouth hood on the inlet

2) Definitely leave the 2 bags on as this halves the filter resistance and it will take twice as long to clog as a single bag.

3) put the DC outside the shed

4) 6" ducting all the way to machines

5) Spend as much (or more) effort attending to machine ports and breathability.

6) Bell mouth hood on the sander like this
412303

7) Small thicknessers are a PIT to fit 6" ducting to and will probably required a new machine port to be built - post some photos of what's on there now.

8) TS and other tools/machines look for ideas on this forum

[Cal]

Ok, my electrical knowledge is iffy! My father would not be proud of me (sparky by trade)

Thanks Bob, yes I am planning to do the bell mouth on the dc. Will do some measuring of the impeller, noticed that the fins internal diameter is smaller than the 6" inlet. Not sure if this will effect the radius on the bell mouth? I will attempt to replicate your mandrel on the lathe or make the bell mouth out of mdf. If I run into trouble does your offer of making some up still stand?

Will leave the twin bags as you and Barry have suggested.

Will be placing the DC outside in its own enclosure.

Will take some pics of the thicknesser, I will have to redesign the whole plastic exit duct though. That's ok.

This will be fun!

[BobL]

Thanks Bob, yes I am planning to do the bell mouth on the dc. Will do some measuring of the impeller, noticed that the fins internal diameter is smaller than the 6" inlet. Not sure if this will effect the radius on the bell mouth?

If you remove the current inlet ports from the impeller and make a completely new one with the BMH attached you can always convert it back.


I will attempt to replicate your mandrel on the lathe or make the bell mouth out of mdf. If I run into trouble does your offer of making some up still stand?

Yep I still make them from time to time - PM me rather than discuss on the forum.

[Cal]

Yes was planning on making a whole new face and not wrecking the original one. Thanks, will pm you if needed.


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[MandJ]

Are you planning on redesigning yours without the "y" piece? I was thinking if this only has a 12" impeller, would one bag be enough? With no means to measure air volume it is a bit of an unknown.

The port and Y piece area is slightly larger than equivalent 150mm round on mine. I could not detect any real change in Open port static pressure or current with the Y removed - there is the slightest change between filter bags on and off - However I'll point this out again - I have FOUR (4) BIG filter bags - no plastic bottoms.

NOTE: If I make a small pen on the lathe - I can see a (slight) change in the Manometer from the effects of dust in the bags from that small amount of turning and sanding.

IMHO I don't think it's worth the effort of removing the Y piece - for almost no gain - unless you plan to change the orientation of the motor intake for ducting reasons.

I had NO need to line my fiber cement cabinet to get noise levels down - you may have to do that with a 12" fan moving a similar volume of air though. Apart from that it should leave a 2HP in it's dust :rolleyes: so well worth the effort - and as others have said, absolutely leave ALL the bags on if possible as dirty bags are a flow killer and more surface area makes a big difference.

[Cal]

MandJ, thanks. Good to know. Mine has cloth bags along with the felt filters also. I will stick with everyone's suggestions about leaving it as is. As I have no measuring devices at the moment i have no way of knowing if I am improving flow or making things worse anyway.

The main issue I have is where the dusty will be enclosed, as I only have a metre behind the shed. The ducting is going to have a 90 degree bend as soon as it enters the shed. I can't see a way around this at the moment. I would have liked the duct to enter straight in and at the most have a 45 degree bend or less. I have a large shelf unit that will need to be moved and a sink that can't be moved from the corner of the shed where the duct will enter. I think I will need to empty the shed out (big job) to see how or if I can get around the problem (if it is one?)

As for the enclosure, still trying to work out what to make it out of that will be cost effective and reduce the noise level and I don't have much space to play with.


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[BobL]

MandJ, thanks. Good to know. Mine has cloth bags along with the felt filters also. I will stick with everyone's suggestions about leaving it as is. As I have no measuring devices at the moment i have no way of knowing if I am improving flow or making things worse anyway.

The main issue I have is where the dusty will be enclosed, as I only have a metre behind the shed. The ducting is going to have a 90 degree bend as soon as it enters the shed. I can't see a way around this at the moment. I would have liked the duct to enter straight in and at the most have a 45 degree bend or less.
Get your self a large radius DWV bend. Its not sold as a "Large radius bend" It's a Male-female DVW bend shown in this thread
http://www.woodworkforums.com/f200/air-flow-calibration-measurements-213627/3#post2022630

It that thread I show a graph that shows that bend only loses 1% of the flow and is equal to a single 45º bend so it should work for you just fine.



As for the enclosure, still trying to work out what to make it out of that will be cost effective and reduce the noise level and I don't have much space to play with.
OK - looking at your setup it would be tempting to just string a roof between the shed and the fence and build a wooden shell under that to house the DC and stuff the gap between the shed and the fence with acoustic rock wool, but then how do you get to the DC to empty the bags. What about cutting a double doorway in the side of the workshop and accessing it from there. You could store gear or a mobile bench in front of the door as you won't need to access it very often. You just couldn't put a permanent cupboard or bench there.

[Cal]

Thanks Bob! That's just the ticket!

I thought about putting a door either end of the enclosure but the issue with that is all the milled timber I have stuffed down the side would make it a pain to get to the second bag anyway. Your idea of access through the shed may work. Will think about that as an option. May be a good spot for the lathe? I have to redesign the layout anyway as I have quickly outgrown the shed, the junk has to go. I have mentioned to the good lady that I will have to take over the unused carport at the front of the house to store the out of house stuff (Xmas deco's etc)


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[BobL]

Thanks Bob! That's just the ticket!

I thought about putting a door either end of the enclosure but the issue with that is all the milled timber I have stuffed down the side would make it a pain to get to the second bag anyway. Your idea of access through the shed may work. Will think about that as an option. May be a good spot for the lathe? I have to redesign the layout anyway as I have quickly outgrown the shed, the junk has to go. I have mentioned to the good lady that I will have to take over the unused carport at the front of the house to store the out of house stuff (Xmas deco's etc)

I was going to do the same thing with the enclosure outside my shed but as I have 1.25m between the shed and the fence I went for a 700 mm wide enclosure with 100 mm of that being the doors.
I have 3 doors ~600 mm wide that don't quite open all the way but its enough to service the machine. To get the DC into the space the doors have pin type hinges and a re easily removable.

[Cal]

The only other option I have is in the middle of the left side (6m with PA door) wall, there it would face the house and there is about 2 meters between the house and shed. I have a water tank against the house closer to the side fence so it would be a zigzag to get to the rear of the shed. Will take some better photos of this to give a better idea. It would certainly give me more room to empty bags and clean filters etc.


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[Cal]

Here are some pics of the shed. You would never know I spent 20+ years as a photographer!

https://uploads.tapatalk-cdn.com/20170515/d3396ff83a2d627151df92baa79dc932.jpg

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I don't have enough room for two doors into the dusty from the shed but one may work on the right closest to the centre of the shed and place the other one outside on the left. Otherwise on the side wall.

Don't mind the mess!

[NeilS]

3hp with a 10amp plug!

Cal, good buy at that price.

Those 3hp models from Leda don't come with a plug. They are meant to be wired in to a 15amp circuit or have an appropriate 15amp plug fitted to suit your 15amp outlet.

I opened up the inlet on my 3ph version to 10" and it has been running my cyclone ok for many years now.

[QC Inspector]

In post 20 you mentioned a 90 degree bend out of the dusty. Is that to get to ceiling height? If so you can take the dusty and turn it upside down and hang the base from the top of your lean to. You only need to disconnect the bag rings at the "Y" and turn them upside down keep the orientation the same as it is now.

Pete

[Cal]

NeilS, there are two models of 3hp units from ledacraft mine is the "portable" dc2200 Dust Extractors : LEDA CT-213 DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-ct-213-dust-extractor-detail)
Dust Extractors : LEDA DC-2200 PORTABLE DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-dc-2200-portable-dust-extractor2012-02-21-03-44-30-detail)

Cheers Cal.

Pete, was thinking of adding a couple of "y" junctions on the way up to service the lathe and belt sander. The thicknesser, ts and mitre saw can be serviced by the overhead duct. The mitre saw at the end of the run, approx 10 metres of duct to get there via the ceiling.

[BobL]

NeilS, there are two models of 3hp units from ledacraft mine is the "portable" dc2200 Dust Extractors : LEDA CT-213 DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-ct-213-dust-extractor-detail)
Dust Extractors : LEDA DC-2200 PORTABLE DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-dc-2200-portable-dust-extractor2012-02-21-03-44-30-detail)

Cheers Cal.

Pete, was thinking of adding a couple of "y" junctions on the way up to service the lathe and belt sander. The thicknesser, ts and mitre saw can be serviced by the overhead duct. The mitre saw at the end of the run, approx 10 metres of duct to get there via the ceiling.

10m duct runs are a but of an ask for a 3HP system so don't expect too much at this length of draw,


In post 20 you mentioned a 90 degree bend out of the dusty. Is that to get to ceiling height? If so you can take the dusty and turn it upside down and hang the base from the top of your lean to. You only need to disconnect the bag rings at the "Y" and turn them upside down keep the orientation the same as it is now.

Watch out as some filter bag holders have structure inside them for which correct vertical orientation is essential for them to work correctly. These may need to be left in the same orientation if the DC is flipped,

[Cal]

Thanks Bob, I don't expect a lot of flow over at the mitre saw, I am trying to condense the other machines as much as I can to reduce duct length. I will endeavour to draw up a layout proposal for the machines and post it up for your critique. I may either add the shop vac to the mitre saw (along with duct) or use it outside the shed.

I think at this stage I will stick with your idea of leaving the DC as is, flipping it is going to be a bit of an issue re hanging it in the enclosure an then being able to inspect the impeller at intervals. It would be a shorter run of duct to the lathe and belt sander leaving it alone. I only want to cut one hole in the shed though so it needs to be right ( or as close to) Cheers Cal


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[NeilS]

I opened up the inlet on my 3ph version to 10"

Correction, that should have been 8" inlet.



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[NeilS]

NeilS, there are two models of 3hp units from ledacraft mine is the "portable" dc2200 Dust Extractors : LEDA CT-213 DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-ct-213-dust-extractor-detail)
Dust Extractors : LEDA DC-2200 PORTABLE DUST EXTRACTOR (http://www.ledamachinery.com.au/index.php/dust-extractors/leda-dc-2200-portable-dust-extractor2012-02-21-03-44-30-detail)

Cheers Cal.


Yes, Cal, had I been able to look at the image in your 1st post (Taptalk doesn't always display images for me) I would have seen that yours has a 6" inlet, mine is 8".





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[Cal]

Well with the working week ended I have a whole load of work to do in cleaning out the shed (some of it) so I can set out the machines to make best use of the space and proximity to the ducting. I want to lay it all out before deciding on where the DC will go outside. I scored (free) a 2.4mtr length of 150mm pvc today. And bought some fittings too. Will post when things are in place for all of you to add your wisdom to my puzzle [emoji1]

[KBs PensNmore]

Cal, when you've sorted your shed out, care to come and do mine.:D
Kryn

[Cal]

Yep sure Kryn, year 2086 suit?


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[Cal]

Ok, so used my initiative and decided to place the DC central of the side wall. It is going to be the best place to gain access for both bags.

https://uploads.tapatalk-cdn.com/20170520/1df2cd5fb6c7b8f29ee185ff5da2e456.jpg
Slab is down! Approximately 1750x900 should give me enough room to use 70x35 frame, insulation and mdf on the inside with colourbond exterior and roof to match the shed.

Here are a few pics with some of the mess cleared out.

https://uploads.tapatalk-cdn.com/20170520/a5a82b54739bdf0258b1bc350c158730.jpg

https://uploads.tapatalk-cdn.com/20170520/df6c1c5fa47a4d80fae5830dfa8bda79.jpg

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From where the slab sits the duct should come in where I have the bend sitting against the wall. I will have to sit the DC on some timbers to raise it up to clear the bottom top hat.

Approximation of where the belt sander may go, further along the lathe. The thicknesser will need to go on wheels and roll into position when required same with the triton and router table. Hopefully I can then just use the shortest runs of ducting I can.

What do you think???

[Cal]

Ok, frame is up! https://uploads.tapatalk-cdn.com/20170521/183dda0dd081c6ae271656792703420f.jpg

Just sitting on the slab as it is still green, will bolt it down next weekend. Got some colourbond for the roof from the dump cost a whole three dollars!
Will continue over the next week.

[Cal]

Well I have had some progress on the shed for the DC today. I have been trying to get some cheap/free colourbond the same as the shed with no luck. I rang the mob I got the shed through and they had some excess 3 metre sheets and wanted $20/ sheet, purchased 4 of them and had a spare one here. A mate at work mentioned he had some mdf/ply packing sheets at home, got a trailer load of them this morning. They have been out in the rain but for the DC shed they will be fine. The outside wall is now clad as is the roof. It is raining now, so that's put a stop to it at the moment. See if I can get more done tomorrow.


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[Cal]

A little more progress today between showers. Started the lining and insulation.

https://uploads.tapatalk-cdn.com/20170528/f6d5a4264aebefed6edb8aa42270f606.jpg

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The local dump had some colourbond downpipe so I got the nibbler out and cut down its length to form flashing for the timber frame, should help protect it from the weather. Got some vents from Chris aka Node101 (thanks!) I hope this should help the DC breathe a little?

Cut the hole in the shed for the ducting, will require a little expandable foam to fix the bad cutting!
It has been slow going compared to framing the shed in the first place, but isn't it always the way

Cheers Cal

[BobL]

Cal, if those slotted vents are all you have for the air to get out it won't be enough.
Either you need to have one big hole or many many more of those slots.

Take a look at the size of the vent we made up at the mens shed and even that has more restriction than I really like.
Fortunately there is a gap under the doors that leads our a fair bit of air.
413258

[Cal]

Thanks Bob, I thought it may have been a bit restrictive with just those vents. The doors will be the same monoclad as the walls, was thinking if I was not to seal up the top and bottom of the sheets would this be enough to help along with the vents? I do have more vents, could add them to the door panels.

Oh, and at the top of the door opening there is a gap of 135x45x800 (see image) where I have not fitted a bearer, this could also remain open as the doors will fit just under the roof line.

[BobL]

a gap of 135x45x800 (see image) where I have not fitted a bearer, this could also remain open as the doors will fit just under the roof line.

It's the cross section of the gap that's important.

so, 45 x 800 mm is OK, 135 x 800 mm is even better, but 45 x 135 mm is still a bit small.

[Cal]

Time to get the angle grinder out again! Will cut some more vents and work something out with both doors. Still contemplating how to make the doors with enough insulation but keeping them light enough. Will see what hinges are around that will suit the weight, gate hinges something along the lines of what you mentioned that you can remove the door if needed. I won't have the need to remove my doors though. Will get some thinner ply for them also.


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[Joseseat]

Standard stainless steel 100mm door hinges would be fine, use 3. Not sure if you've ever lifted a standard solid core external door before but they are pretty heavy, around 40kg.

[Jestar]

You could use a standard duracote door. Lighter than a solid but still has the water resistant skin. Also cheaper than solid core.

Don't forget to put a drip flashing above whatever door you make/use.

[BobL]

Remember if you want noise reduction you want a layer with some "weight" or more specifically, "high density" and you want a layer of low density as well.
The doors on my enclosure weight around 45kg each.

[Cal]

Yes, aware of this. The ply I have left is 32mm thick, a little too dense. Will be making frame 90mm deep with insulation as per the walls and colourbond on the outside to match the shed. I understand that there will be some weight to the doors but don't want to go overboard.


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[tonzeyd]

Doors don't need to be super thick/heavy, just use the right materials for the job.

In my enclosure I've got 4mm mass loaded vinyl and 50mm acoustic sound foam. Walls are lined with 12mm plywood. All seams are overlapped and taped.

I haven't measured db to get actual readings, but to give you an idea standing inside the shed with it running, theres significantly more noise coming from air movement in the ducts which i'm more than happy to live with.

Also might be bit late, but does that enclosure have sufficient room to not touch the side walls? As DC's create a fair bit of vibration/harmonics which might end up turning your shed into one big vibrating speaker.

[Cal]

Thanks tonzeyd, I have started on the doors this arvo, just ended up making a frame from 90x35 and a noggin in the centre then screwed 12mm ply to it. Will have batts in them also, then the colourbond monoclad. There is plenty of width and length to the shed so it doesn't touch the walls at all. I cut the hole in the ply oversized for the duct too. The only thing I will check on is the hole in the shed wall as the duct is a tight fit there. I still have a bit to do to get the enclosure finished so it may be a few weeks away before I get to turn the DC on in the enclosure. Will see how I go. Cheers Cal


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[Lappa]

I ran a short length of smooth inner wall flexy ( approx. 250mm), just after the inlet to the DC to the main pipe. This prevents any vibration transferring into the pipes in the shed.

[BobL]

The ducting through my shed wall is a large radius 90º (6 x 15º) PVC elbow so it is a slot rather than a circular hole. I just cut it 15mm oversize. I then cut up and stuffed foam rubber strips into the gaps.

[Cal]

Good ideas gentlemen thank you both. [emoji1]


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[MandJ]

Interesting, I have a very tight fit through the shed wall for the 150mm hard ducting, it's about 500mm from the DC intake, no vibration through the shed at all. The ducting hole through the wall of the DC cabinet is large and has one of those heavy rubber seal plumbing boots around it as I was more concerned about vibration into the cabinet from the DC. Noise from the DC and cabinet is so low that it could be used at midnight if we wanted.

[BobL]

I was more concerned about vibration into the cabinet from the DC.

That was my problem because initially I removed the DC from the stand and had the DC suspended from the walls of the enclosure (B).
413518

I tried all manner of rubber mountings etc under that metal lip (L) and in the end I gave up and put the support legs back on and supported the DC back to the brick paved floor of the enclosure.
This worked very well.
413519

[Lappa]

The reason for my short piece of flexy was that any vibration or movement from the DC, no matter how small would be transferred into the piping in the shed and it was with a solid link. The flexy fixed that. If there is vibration in the cabinet then there must be some movementt, even if minimal which will be transferred to the pipes via the solid connection.

[Cal]

I am going to have to do some wrangling with the ducting into the enclosure. I initially thought of raising the DC up a little to allow for the fact that there is a top hat in the way at the level where the DC inlet sits. I did my initial measuring and decided on a height for the enclosure to allow for this, this measurement was a little out [emoji848]I don't have the height I thought I did. About 100mm out. I didn't account for the 10* pitch on the roof.

The plan was to run a 90* bend part the way through the wall and a straight pipe to the DC. I will do some fiddling around with 2 45's and see how that turns out. If not, a bit of flex I guess.

I still have a bit to do on the enclosure, one door hung (needs cladding) and hope to get the flashing on the other end and both doors this weekend (rain is on its way on Monday). Early start in the morning.


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[MandJ]

If you use a 90 bend make sure it's the wide bend fitting - BobL did a lot of testing and the difference is marked, flex is really not good, 90 with good radius is better than 2 x 40 from memory, just on my way out so don't have time to look it up.

[BobL]

If you use a 90 bend make sure it's the wide bend fitting - BobL did a lot of testing and the difference is marked, flex is really not good, 90 with good radius is better than 2 x 40 from memory, just on my way out so don't have time to look it up.

see this thread for details
http://www.woodworkforums.com/f200/air-flow-calibration-measurements-213627/3#post2022630

While we are talking about flexies, it seems like wall smoothness has less of an impact on flow restriction than stiffness.
The flexy with the ""stiffer corrugated walls is LESS restrictive than the "softer smooth walled stuff.

One mechanism I can think of is the more flexible stuff moves (even a little) under internal turbulence of the rapidly flowing air and acts as a momentum sink.
The stiffer stuff resists movement forcing the air to retain it's own momentum

It appears the only reason for using the softwalled stuff is where super flexibility is essential - otherwise I'd say use as stiff a flex as you can find.

[Cal]

Got a door almost complete today. Still need to insulate and finish the ply. Added flashing to the rear doorway and a bit more ply to the wall against the shed. It's a slow process dealing with secondhand material, had to de-nail the ply before cutting it. The "flashing" (downpipe) was donated by my shed, have replaced it with pvc for now. Will get more at a later stage to replace what I have stolen from the shed.

Here is the door. https://uploads.tapatalk-cdn.com/20170603/570bf326f51f32eb081389ab29775f12.jpg

[Cal]

Had a family outing today, managed to get the second door hung this morning before we left and the cladding on in the last hour. It's now weather proof! Will see what else I can get done over the coming week.
Oh, and some 150mm pipe (2.5mtrs) from the dump and a bit more flashing for a princely sum of $4!

[Cal]

Quick update, the DC shed is now fully lined and power an dusty in place. I still need to create some more vents but for now at least the dusty is out of my shed and I can start cleaning up again! Will start working on rough placement of machines over the weekend.


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[heybluey]

Cal, I'm also about to embark on the same journey as yourself with building my dusty shed and getting all the ducting in place which will be the focus of a WIP thread soon. I believe you're in Adelaide from some of your posts so thought I would share my recent experiences with sourcing 150 stormwater fittings and ducting for anybody that maybe interested.

In Adelaide I've found it a bit hard to get hold of 150mm stormwater fittings and flexible ducting to fit nicely to a 160mm OD PVC stormwater pipe. I've recently found that both irribiz out and Viss Water at Virginia stock 150 mm stormwater fittings, Y's were around $19 and 45bends were around $14 which I thought was reasonable and haven't been able to find too many others local.

In terms of flexible ducting I've just come across Total Rubber who quoted my around $330 for 10m of their 160mm ID Ductaflex, spec sheet attached. I thought that price wasn't too bad, what are other peoples thoughts?

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[Cal]

Thanks for that. As I am rural (Strathalbyn) we have irrigation suppliers in town, prices are similar to what you mentioned and everything is on the shelf. I got two lengths of pipe @2.5m each for $2 total, well one was free and the other $2 from the dump. The irrigation shop wanted $65 for 6mtrs, compared to Bunnings and tradelink who were well over the $100 dollar mark.
I hope to only use a small amount of flexi, 10mtrs is way too long for me would never use it all. I haven't looked at what's around yet, it's been a job just trying to have the time to finish the enclosure.
Look forward to seeing your WIP, I am now trying to clean out the shed to start placing machines. I have so much wood in the way, all off cuts and stuffed everywhere. Clean up begins! [emoji37]


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[NeilS]

In terms of flexible ducting I've just come across Total Rubber who quoted my around $330 for 10m of their 160mm ID Ductaflex, spec sheet attached. I thought that price wasn't too bad, what are other peoples thoughts?



The 150mm flex ducting that we connected to the 150mm fixed ducting at our local Men's Shed just fitted inside the 150mm 'fittings'. A tight fit, but it does go in with a bit of encouragement​.

In Adelaide we sourced the flex ducting from Carbatec and Leda. Your price for 10m of 160mm is about the same per metre, but if you need less you could save some $s. There are also fittings (clamps and gates) for 150mm flex that may not be readily available off the shelf for 160mm.

[Cal]

So with the day clearing and cleaning done here comes the challenge. Some photos of what space I have to work with and an approximation of where I may place the lathe and sander. Open to options and opinions with all of this too.
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The way things sit, the sander and lathe are too close together and there is little room for sorting out the ducting cleanly, my other thought is to sit the lathe or sander on the back wall and run the ducting along the wall over the sink and around the corner. I need to make a dedicated table/stand for the lathe to sit on and would like to upgrade it in the future (not sure what I will end up with yet)
So fire away and let's see if we can nut this out as a team! [emoji848]Cheers Cal.

[BobL]

Yep it's going to be all too crowded if you try and connect at Bench height level. It will ruin your wall space which is always a premium in a shed. I would take the ducting up over head height and out and down to where you need it.
It uses more pipe and more junctions but it will make it easier to connect up other things

[Cal]

That makes sense Bob thanks. I think if I use the "y" where it sits to service the sander then run the pipe up to another "y" then do a run along the wall so the duct sits under the shelving on the back wall and set the lathe up there. The duct can then run straight up to close to ceiling height then run toward the centre of the shed for table saw and thicknesser (wheel them into place when needed)


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[Cal]

Made a new bench for the lathe today, it sits on the back wall. I love free timber! Will buy some MDF to clad the walls before tackling the ducting.
https://uploads.tapatalk-cdn.com/20170611/2619fba29b113e3dfe5ef00182bafa35.jpg

[Cal]

Some progress on the shed. MDF is up and painted with insulation also, what a difference a bit of white paint makes [emoji41]
Ducting journey has begun, I still need to create a bell mouth and new cover plate for the DC, figured I would get duct over to the lathe and use the DC while I create the mandrel on the lathe. Need to buy some more bends and "y" pieces. It is slowly getting there.

https://uploads.tapatalk-cdn.com/20170616/6ae0d288714ef6603f74528489fd3312.jpg

[BobL]

Cal, if that horizontal ducting arm is going around the wall just to service the lathe then the best place for the Blast Gate should be near the junction and not the lathe.
As shown here
414321

However I would serious reconsider running that ducting arm at that height around the wall because it encroaches into high priority shed space along the wall. I would look at getting that arm up much higher (above that switch even)and then dropping down to the lathe. This frees up the valuable wall space.

[NeilS]

I still need to create a bell mouth ....., figured I would get duct over to the lathe and use the DC while I create the mandrel on the lathe.



Cal

A mandrel is the way to go if you need quite a few BMs, but if you only need one or two ot then turning them out of wood will be just as quick.

[BobL]

Cal
A mandrel is the way to go if you need quite a few BMs, but if you only need one or two ot then turning them out of wood will be just as quick.

It depends to some extent what they are made of.
If an MDF sandwich is used as the turning stock then this takes time to cut/glue/turn and this will definitely be slower than turning a mandrel.

A good turner will no doubt be much faster than myself but I reckon turning a mandrel takes less time (I reckon about half as long) than turning a complete hood because there is now hogging out of the middle.
The heat forming time of a PVC hood only takes about 5 minutes.
By the time the second one is made you should be well in front.

The advantage of turning them individually is they can be tailored in shape to the situation which otherwise would require individual mandrels to be made..
For example minimum radiuses edge hoods work better behind lathes and in tight spots.
Where there is room you might want to look at turning a more tapered hood (5B) and/or with a wider lip (next one down).

414325

Bear in mind that the bottommost profile cannot be formed from PVC pipe without tearing the edge.

[Cal]

The arm in the previous post is just to the sander. I am running another duct up high (see below) for the lathe.

https://uploads.tapatalk-cdn.com/20170617/662da561c59c4cf6a812d36d0a077f5d.jpg

Bugga, didn't think about the blast gate for the lathe, will have some fun getting that apart now!

I am by no means a good turner, will try my best and see what comes of it. Otherwise I will have to put my order in for some hoods.

And another pic, just temporary at the moment so I can start on the mandrel.

https://uploads.tapatalk-cdn.com/20170617/6132838e0caeb12e2f4ff6f0def620cf.jpg

[Cal]

Mandrel roughed out from two pieces of poplar. Will need to mount some mdf to the base to add some width and strength as there are a few cracks in it and I am at about 210mm not 225mm as per Bob's former. The core is approximately 160mm at the moment.

https://uploads.tapatalk-cdn.com/20170617/d083a3bbbfe4611d97fb55058969e4fc.jpg

[Cal]

Well I didn't get much done today, the better half wanted to make some jewellery so the dust making stopped. That's okay. I finished off a clock face instead.
https://uploads.tapatalk-cdn.com/20170618/d767da6ef40c7b6baf884f25fdbce9e5.jpg

[Cal]

Success! Bell mouth hoods worked, pushed it to see how far I could go. Used a ceramic heater and hot air gun to get it all hot. Run a cake of soap over the mandrel to get it slippery and off I went. The hoods once formed and cooled just fell off no force required.

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I did have a couple of small splits and one major one, once you get a feel for how fast to wind the tale stock you really don't have any issues.

On to the blast gates! [emoji1]

[BobL]

Good to see the production happening.

I notice some of the lips are rolling over, one quite a long way - this is not a good idea as it will result in more air being drawn in from the back of the hood - this means this will find it harder to get around the 180º turn and collide with other coming straight into the hood air and result in turbulence. If you want to err on the side of caution then turn the wooden former so the edge of the lip is less than 90º to the side of the pipe.
m cut the make the final

[Cal]

And here I was thinking I was clever ☹️
Will see if I can trim them off, if not will make more as I need them.
I have modified the DC inlet, ended up cutting the original cover and inserted a hood in an mdf/melamine sandwich. Bit of fiddling but hope it's ok.
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[Cal]

And a couple of blast gates. The one in the foreground has ended up too flimsy as it's using 3mm acrylic and the hole doesn't leave much meat on the sides. Will possibly replace with mdf.
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https://uploads.tapatalk-cdn.com/20170625/087df0e3b4f2a21885501130bdabebdb.jpg

How's that Bob??

[BobL]

Bewdyful :2tsup:.

[Cal]

I have a bit of time off work this week and have made yet another blast gate. I am working very close to the wall so a swing gate or sliding gate is not going to work on two of the machines (sander and lathe). Here is what I come up with.

https://uploads.tapatalk-cdn.com/20170704/8051fe366553a7f9da2b756a49cff88c.jpg

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I placed a dowl in the back of the centre piece to locate the closed gate, hope this won't upset the flow too much.

[Cal]

Two down, onwards and upwards!

https://uploads.tapatalk-cdn.com/20170705/e02b40421c3557effdc73baf9f473bcf.jpg

[BobL]

When you get sick of swapping the inner gate panels over you can put vertical sliders where the lines are shown in the goto..

415745

[Cal]

Will see how it goes, thought the idea was to get the gate as close to the "y" as possible.....


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[BobL]

Will see how it goes, thought the idea was to get the gate as close to the "y" as possible.....

Yep, but when the take offs/connections are upwards/horizontal like yours, sawdust moving in the other duct will find it harder to get around the corner and up into the other duct. Most of that sawdust will also tend to fall out when you turn off the DC. In this case you can move them to a more convenient place. It's when the connections are heading downwards that you can run into real problems. The the sawdust is dragged into and falls into the duct. When the DC is turn off the sawdust stays there and builds up. If that duct is not used for some time the sawdust can pack in so hard the DC won't clear it when the BG is opened.

Here are a couple of examples - View is from the side with Arm C above Arm A and B.

Being at the lend of the line, Arm A is the least problematic,
The BG could even be located at machine level, except perhaps if it's something that generates a high dust load like a thicknesser, and there is stall in the middle of the job the sawdust in the pipe will fall back down anb bog up that arm. The best place for a BG is up near Blast gate B2.

415766

Arm 2 is the problematic arm.
If the BG for arm B is at B1 and arm A is in use , some sawdust passing Arm B will either drop or (by Bernoulli)be dragged into Arm B (blue arrows) and if there is nothing in the way it will fall all the way to the bottom of the duct. If Arm B is not used for some time this may end up packing the whole arm with sawdust. Clearing these blockages are a PITA so the best place for the BG for Arm B is at B2

Sometimes you cannot locate a BG at B2. Then you need to either remember to regularly open B1 and clear any sawdust from that arm. An alternative is to insert what is know as a "clearing Y" which catches the sawdust drawn it Arm B while Arm A is in use - periodically the screw cap is removed (with DC ON) and the will clear the sawdust built up in the tra.

Arm C is the least problematic. No sawdust will fall into it and sawdust dragged upwards will tend to fall back out when the DC is turned off. BG can be pretty well anywhere along this arm.

[Cal]

It is slowly sinking in now Bob! I will look at moving them at a later date, they are in a bit of a problem spot for reach as they both sit over/behind the sander. Moving them another foot or so is not going to improve the reach though, but as you point out changing them over versus sliding adds to the problem. I still need to shuffle some other items around in the shed to allow better access to all machines. The main bugbear at the moment is the bench, at 1500x900mm it takes up a lot of realestate in a small space. I plan on rebuilding it to a more suitable size.

I don't envisage having any solid drop downs in ducting as all that is left is the TS and thicknesser, which will need to run off flexi and be wheeled into position front and centre of the shed. I have now run a duct into position overhead for this. The mitre saw still remains an issue as it is on the opposite wall to the DC and as I have mentioned previously it will be about 10mtrs of duct to get to it so flow is going to suffer. I may have to just lug it outside to use it.


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[Cal]

Just to add a little more to my progress which has been slow to say the least, I have just changed the intake to my poor excuse for a thicknesser. I ditched the 4 inch outlet and went straight to 6 inch, I have not given it a test run as yet and may have to add a rim to it where it sits on the jointer top to add a bit of space between the cutter head and the entry to the duct (not sure if it’s too close or not)
https://uploads.tapatalk-cdn.com/20180414/ab7a511b0ad11ec9ee84ea03fa27079e.jpg
I have a way to go to get the rest of the machines hooked up, hoping to get those sorted in the next few weeks.

[Cal]

Another bit done, have enclosed the dirty beast that is the mitre saw. Will be glad when it’s hooked up, hope there will be a lot less mess!
https://uploads.tapatalk-cdn.com/20180415/04d2c4c69f3e30cd775e248afbb5a92e.jpg

[BobL]

One thing you could do to give your setup a bit more flexibility would be to put some hinges - maybe even piano hinges - as show in the photo below.

The first line of hinges would be at the red lines so you could open the two panels like doors either side of the saw - you would need to trim the bottoms of these panels to get the panel bottoms past the work piece backstops.

Then these two movable panels might get in the way of the workpieces so you need a second line of hinges (green line) about half way back on the side pieces which would allow the connected doors to open operate like wings.

The wings could be tucked in as closed as the panels are now - or opened out wide to catch more stuff flying off from teh saws?

433722

[Cal]

Thanks Bob, never thought of that, good idea as usual! That will also help in being able to use the saw in anything other than 90degrees too! I have to buy some more ducting and junctions etc before this will be hooked up, hope to get it sorted soon. Cheers Cal

[Spyro]

I did a similiar enclosure for my mitre saw, and it was doing absolutely nothing.

Then I realised that half the dust was actually escaping from under the base of the saw, between the metal legs. Under the saw is a very irregular shape so I ended up stuffing it with sponges and that helped a lot. Easy fix.

The other half of the dust was escaping from high up, when the saw is down and cutting. So I cut a few strips of thick PVC film (the type they use for outdoor patio roll down blinds) and hang them from the top of the box on the outside making sure they overlap a little, and cut them short enough so they don't get tangled in the blade. That helped a lot too.

[BobL]

I did a similiar enclosure for my mitre saw, and it was doing absolutely nothing.

What size is your DC and ducting?
How long was the ducting run back to teh DC?

[Spyro]

What size is your DC and ducting?
How long was the ducting run back to teh DC?
I did all that testing and modifications before I actually connect it to anything, I wanted to make sure the box keeps most of the dust inside.

[Cal]

So how do you confirm it was useless when you did not have a DC hooked up to it? I’m confused [emoji52]

[BobL]

So how do you confirm it was useless when you did not have a DC hooked up to it? I’m confused [emoji52]

He's talking about visible dust, and wanted the majority of chips to be contained in the box by the box design alone which seems like an admirable course to take.

I started to write a long reply about fine dust, yada - yada, air flow, Yadda - yadda and then realized I was in broken record mode again.

In summary;
Even though I often use it as a starting point, testing based solely on what chips (visible dust) are doing does not always indicate what the fine dust will do. I see this approach used time and time again on this forum - can't see any dust (ie chips) thing so it must be working.

This is the same principle that most WW machine manufacturers use, ie 4" dust ports and narrow down gaps in machinery cabinets so chips don't escape. This is one of the major reasons why woodies have a fine dust problem in their sheds.

Unfortunately without a fine dust detector we can't say much about what the fine dust is doing. In general chips act like marbles and follow initial high speed ejection/collision trajectories and/or high speed air flows. Being more gas like than chips, fine dust follows air flows including thermal air currents, and general diffusion (high to low concentration regions).

Fine dust behaves like a fart and the only way to deal with it is to use high air flow. This means forced ventilation and/or large area cabinet ports or openings, more powerful DC and large ducts to allow for as high and air flow as possible. Really high/fast air flow can reduce or eliminate chip scatter as well, which is why I asked Spyro my original questions.

Whoops slipping into broken record mode again: Last point
Remember the fine dust is the one to worry about that need to be grabbed at source, the chips can be swept/vacuumed up later.

[Cal]

That’s what I thought Bob, it’s not really a good indication that the box is doing it’s job based only what the chips are doing. I can’t see that this box will even extract all the visible dust, I am hesitant that it will even help with fine particles but willing to try anything, although without a particle counter I may be blowing wind up my own ....
I only hope it helps to some degree??? Will put the hinges on it as you suggested also. I think I mentioned in the thread a while ago that mitre saw will have the longest duct run of any of the machines approx. 6 metres, there is nothing I can do about that as I don’t have space enough to fit it on any other walls closer to the DC, I just have to suck it and see (or not)
I wonder if after it has been used that I open another gate to a bmh that is behind my lathe to help suck out any dust that will still be hanging around the shed? I ask this because I can’t see that the duct in the box of the SCMS won’t do as good a job at removing the fine dust that is not already in the box.

[BobL]

That’s what I thought Bob, it’s not really a good indication that the box is doing it’s job based only what the chips are doing. I can’t see that this box will even extract all the visible dust, I am hesitant that it will even help with fine particles but willing to try anything, although without a particle counter I may be blowing wind up my own ....
What you can do is try the barn door effect at different opening widths and see what happens. My limited experience with and watching Mens shed users of SCMSs is users tend to use them way too hard.

John Samuel's thread on making a SCMS hood was interesting. He found that stabbing at the work with a low TPI blade produced a lot of chips that bounced all over the place even though he was using a Clearvue. This is because the chips are being ejected with a velocity higher than the air flow.

When I suggested he approach the cuts more slowly/smoothly he got far less chips (and almost certainly more fine dust) which all appeared to be instantly swept away by the high airflow produced by the Clearvue. Surprisingly he also got a better cut :oo:

In JS thread we discuss that one way to force this issue is to use a higher TPI blade. The next question is what is happening to the greater amount of fine dust? Well this should not be an issue provided you have enough air flow and this is exactly what I see on my TS when the particle counter


I only hope it helps to some degree??? Will put the hinges on it as you suggested also. I think I mentioned in the thread a while ago that mitre saw will have the longest duct run of any of the machines approx. 6 metres, there is nothing I can do about that as I don’t have space enough to fit it on any other walls closer to the DC, I just have to suck it and see (or not)
6m is OK for your DC, on a 2HP DC I would have a slightly more concern.


I wonder if after it has been used that I open another gate to a bmh that is behind my lathe to help suck out any dust that will still be hanging around the shed? I ask this because I can’t see that the duct in the box of the SCMS won’t do as good a job at removing the fine dust that is not already in the box.
Yep, Anything that increases air flow removal will help.

[Spyro]

For clarity, I haven't installed anything permanently yet, I'm new to this space and still researching things.

But with that SCMS enclosure I built, I'm talking that it was blowing a huge flow of air, like a massive hair drier directly to my face. My head was literally white after 10 seconds, so I figured that this was probably not a good starting point. Now I understand that this behaviour would probably change with a strategically placed powerful hose, but I also don't see how improving the design could actually hurt either.

[BobL]

I know exactly what you mean, you don't really want that crap going up your nose - that's a "sino-nasal cancer "in waiting when I think about it.

It reminds me of the time a couple of decades ago I had probs with the spring clip on the crappy little dust bag on the back of the Makita belt sander. I got behind the bag and fired up the sander, The blast from the internal fan blew the bag off and as the insides of the dander was clogged with sheoak dust some of which went right up my nose. I was sneezing for many hours after that one.

Adding at least a 2HP DC should remove most if not all of of that blast.

[Cal]

Thanks Bob, the saw has a high tpi blade on it and I use it accordingly, slow and steady. I do tend to run the DC for an extended amount of time when ever there is a dust making exercise so it won’t be out of the norm to do this. I can always add Spyro’s suggestions into the mix if there are any issues. Cheers

[Cal]

Some new and improved vertical blast gates, they hold in position well on there own for the most part. I have made a pin for one of them as it is a little looser than the others. I added some mdf to the sides of two of the gates (dowelled) which will serve well in keeping the duct in place along the length of the wall, will add an aluminium bracket to the centre where one of the “Y” junctions will be. I added an iron on strip of melamine to the edges of the fixed pieces that the gate slides against to overcome the fluffy edge of the mdf binding.

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[BobL]

Nice handles!

[Cal]

I think so [emoji16]
Better than drilling and screwing in the end of the mdf, no splits!

[Cal]

A Little more work done today, all the blast gates are finished and starting to install everything.
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[QC Inspector]

Cal you have two blast gates to the right of the one on the left of the clamps. If they are closed why do you need the one on the left?

Pete

[BobL]

Cal you have two blast gates to the right of the one on the left of the clamps. If they are closed why do you need the one on the left?

Pete

It's not so quite critical on a horizontal run but if that was a vertical run then not having the one to the left of the clamps would collect sawdust in it from when the sawdust is travelling down through the vertical ducting. Air rushing past an open duct creates a slight vacuum inside the open duct and this will occasionally drag some sawdust into the open duct.

It's best practice to use a gate to seal off the side arms to a system at the closest point possible to a trunk line to prevent this happening.

So much sawdust can collect in the bottom of the horizontal duct that it will compromise the ID of that duct and the DC may not quite have the grunt to lift the sedimented dust up off bottom of the of the ducting.