Thread: Fletty's new shed WIP ....or is it a retrospective??

Originally Posted by FenceFurniture

Actually, harking back to what Bob once said about the fine dust from a mitre saw not all be propelled towards the on-board saw dust port, I would imagine it would be the same deal with the Wasp - maybe even more so because it would be way slower than a 3000rpm mitre saw blade. That is, the dust that can't be seen would not necessarily be shot from the belt in a straight line towards the intake that I'm proposing (in lieu of a BMH). So perhaps it would be better (with my idea) to make the cavity go about 100mm above and below the width of the belt?

For a sawdust generator like a mitre saw or router or TS blade guard there's always a tradeoff between getting enough air speed to capture the chips and getting enough air volume to capture fine dust so shaping the hood becomes important.

With a sander it's very much about grabbing as much air (volume) as you gan get. To do this you might think that a giant scoop would be the go but the max air that can be pulled from a point in space is always with a BMH and besides things like a giant scoop just get in the way

I have done a bit of testing on the Wasp and and as you would expect compared to a big belt sander it does not make that much that much dust. You have to run the DP at 3000 rpm to match the belt speed of a regular belt sander and because the sander area is small it can't generate the volumes of dust one would normally see on a belt sander. This means that even a 100 mm duct pulls enough air to manage the dust from a Wasp. A 100 mm duct with a BMH should be more than adequate and not get in as much of a way as a 6" duct.

You climbing poles again Alan

Nice shots of the Holden Is this one the new museum ? I heard on the grape vine its owner was involved with Greens possibly his SiL Frank.

Originally Posted by FenceFurniture

Bob's famous description of invisible dust was to think of it like a fart: If someone in the room farts and you have a fan behind you........you'll still cop the fart.

Appreciating the sensitive souls who inhabit this Forum I was a little perplexed by Bob and FF's apparent lapse, so I consulted the esteemed and authoritive Oxford English Dictionery and was eventually directed to page 3420 and I quote:

..... Trump (trʌmp), v.¹ To give forth a trumpet-like sound; spec. to break wind audibly (slang or vulgar).

• ‘As morning broke in the windowless Bedsit, Emma peered wearily out of the bed they'd shared as Michelle trumped loudly and proudly into the already stale air.’
• ‘Half asleep and looking up at him, I yawned a long, deep yawn and just as I closed my mouth and opened my eyes he relieved himself, not by burping or trumping however, but by throwing up into my face!’
• ‘If you were standing in a lift, and someone trumped loudly for half a minute continuously, would you say "yes, impressive!", or would you say "LET ME OUT OF HERE"?’ .....

Who is to argue with the OED???


Cheers

Graeme

Originally Posted by GraemeCook

Appreciating the sensitive souls who inhabit this Forum I was a little perplexed by Bob and FF's apparent lapse, so I consulted the esteemed and authoritive Oxford English Dictionery and was eventually directed to page 3420 and I quote:

..... Trump (trʌmp), v.¹ To give forth a trumpet-like sound; spec. to break wind audibly (slang or vulgar).

• ‘As morning broke in the windowless Bedsit, Emma peered wearily out of the bed they'd shared as Michelle trumped loudly and proudly into the already stale air.’
• ‘Half asleep and looking up at him, I yawned a long, deep yawn and just as I closed my mouth and opened my eyes he relieved himself, not by burping or trumping however, but by throwing up into my face!’
• ‘If you were standing in a lift, and someone trumped loudly for half a minute continuously, would you say "yes, impressive!", or would you say "LET ME OUT OF HERE"?’ .....

Who is to argue with the OED???


Cheers

Graeme

AT LAST, some incontrovertible science .... although I fear that the new President of the United States will soon have the esteemed OED banned?

fletty

Perhaps he'll just have the relevant entry erased, or "edited" to reflect ancient usage

The mini sander/WASP is finished ready for its new task...

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The manifold swings back, to give access to the radius of the bobbin....

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....or forward to optimise dust pick up when working on the 'face'...

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I'll resolve the holes vs grate vs miniBMH vs 'swallowing the workpieces' as I go.

fletty

Originally Posted by ian

Perhaps he'll just have the relevant entry erased, or "edited" to reflect ancient usage

Of just get the ruskies to release some fake news?
Trump - ancient name for god.

Originally Posted by fletty

So Paul, while I'm re-calendaring your 'pin-ups', I've decided to make another one just for Crowie?

Attachment 404935 Attachment 404936 Attachment 404937

PS, it seems all of the Fords broke down in the marshalling area?

Come on Alan, YES I've taken the bite but not quite "hook. line & sinker".....
While I like the old FJ's, Fx's, FB's they just don't have the class of a Ford though from a '32 Hot Rod to a GTHO and a Shelby Cobra but then I'm also keen on an E-Type Jag which would also look good on a calendar of anyones shed or in my garage. We could even include your Morgan for additional inspiration.
THANK YOU for thing of me on Australia Day with those death defying photos.... Cheers, Peter

PS - If you want something Australian, how about a Bolwell Nagari from the early to mid 1970's with a big block Ford.....

That setup look very tidy Letty, it's probably the tidiest I've seen.

In terms of air flow a 50 mm duct should draw about 70 CFM, but holes are less efficient than ducts and because they close together they will fight each other for air.
All up I would guess a 70% efficiency so 70% of 70 * 6 or ~ 300 CFM. Probably enough for many small jobs or at slow speed.

A 100 mm BMH would have close to full efficiency of a 100 duct or about 425CFM

A 150 BMH would have over 1000 CFM, and with a coarse mesh grill could still be around 800 CFM.



,

Sorry, couldn't resist it....

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....but, then again, what else would you call the downstream effect of a WASP?

Let the puns begin....... what else could it bee ?

fletty

OK, I've now got 150mm duct work to (amongst others) my JET table saw but the chip and dust extraction was far from satisfactory? The chamber inside the saw has a floor sloping towards the single 100mm outlet and the 'door' is a deep hinged box which has always puzzled me as it seemed to serve no purpose?
Over several stages of trying to improve dust extraction I have cut a 100mm outlet into one face of the box/door and, more recently, a 150mm outlet into the other side of the 'box'. However, both of these outlets permitted a LARGE and growing collection of chips to fall to the sloped floor!
I now believe that the original dust extraction system (single 100mm outlet at the lowest point and air inlets only via control holes and the gap between the cabinet and saw table) starved the TEFC motor of cooling air and that the purpose of the box/door and its vents, was to provide a source of cooling air for the motor?
This meant that my addition of outlets into the box/door, disrupted the planned (?) airflow and possibly starved the motor of cooling air?
The only solution seems to be to open up the existing 100mm circular outlet to suit 150mm duct work and to re-establish air vents in the box/door. The structure of the cabinet prevents a 150mm diameter outlet at the lowest point and so I have created a 100 X 240 mm rectangular outlet and an adaptor to suit. The cross section area of 150mm diameter duct work is 18,000 mm2 and the area of the new outlet is 24,000 mm2. The following pictures show today's progress...

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The end of the 150mm diameter duct work has a bell mouth and the lower surface of the adaptor continues the sloping floor of the cabinet itself. I should have it running tomorrow..... ?

fletty

Very impressive Alan....

Looks good fletty!

This meant that my addition of outlets into the box/door, disrupted the planned (?) airflow and possibly starved the motor of cooling air?

A 100mm duct connected to a 2HP or bigger DC should be able to draw 400CFM though the duct.
Even though most TS cabinets are not well engineered for air flow they usually can still draw ~200 CFM through their cabinet and even 100 CFM moving through a cabinet containing a large motor is more than sufficient to prevent motor overheating
My 4HP compressor is in a small sound proof enclosure and has a 100 CFM fan venting the enclosure and that is enough to keep it cool when its under load. There is a digit thermometer inside ether cabinet that I can view inside the shed and it usually shows a temperature around 5-10º above ambient even when running continuously.
Yes, compressors are intermittent machines but so are table saws, as it's only when they are cutting full depth that they get anywhere near full load, when coasting they draw much less power and generate much less heat.
The 100-200 CFM is one thing, what concerns me is what happens when the 100 mm outlet become blocked?

The mens shed TS is a H&F unit but the 100 mm placement and internal sloping floor structure of the cabinet is the same as the Jet, even to the point where the motor lead lays on the bottom of the cabinet and obstructs the flow towards the 100 mm duct as shown in your first photo.
The H&F TS cabinet has a some vents cut into the side of the removable section of the cabinet that covers the motor but so many slivers of wood get down between the blade and throat plate and block the 100 mm port, that every week we have to open up the saw base and unclog the dust port.

There is some urgency to do something about the mens shed TS but perhaps I will wait to see how your mod goes and how well it removes the slivers of timber. My preference at this stage is, because we have the room, to to go for a smooth rectangle direct to round, transition about as long (or maybe a bit longer than your black box), similar to the one I made for my combo thicknesser jointer and it works very well. This leaves fewer corners for slivers to get trapped.

FWIW on my contractor TS the motor is outside the cabinet. This makes for a lot more room under the trunion and allows an inverted pyramidal hopper with a 150 mm duct at its apex to be installed underneath the small cabinet section directly under the blade and I have very few problems with slivers although I'm also running a much narrower throat plate than the mens shed TS.

Originally Posted by fletty

...The chamber inside the saw has a floor sloping towards the single 100mm outlet and the 'door' is a deep hinged box which has always puzzled me as it seemed to serve no purpose?....fletty

fletty try and lower the blade to its lowest and tilt it the full 45 degrees. Open the door and have a look inside. My bet is the motor will swing into the box area revealing the purpose of the box.

Mod looks good.

Pete