Thread: The most annoying question(s) - What should I do?

Hi,
I've got a DIY Dust deputy+Vac for the "dust" making tools like sanders, routers, etc. and a hare & forbes dust extractor for the bigger machines. I use a 4m length of flexible 4" hose and wheel the H&F extractor out the rollerdoor to keep the fine dust out of the shop. I've been through the fixed metal pipe with blast gate setup. I found it to be a PITA. There always seemed to be a pipe in the way. I have a 3HP 16" jointer and this setup copes well. Keep-it-simple is now my philosophy. No long pipe runs, elbows, Y joiners or blast gates to reduce the airflow.

The thicknesser is the killer. Unless yours is small and you take light cuts I don't think a shopvac style vac is going to cope with the volume of chips.

I only bought the DIY DD last week ($69 at Carbatec) and I love it. I separates all but the finest dust. I made a MDF collector box on castors rather than use the 20L plastic bucket. It's very stable and doesn't tip over when you drag it around by the hose.

Good luck

Given that you're willing to wheel the DC around to plug it into the "machine of the moment" I wouldn't bother going up to the 6" duct.

Where that excels is in long, fixed runs connecting all of your machines.

For a single machine at a time, I suspect that you won't notice any difference between a 4" and a 6" duct. So I'd settle for converting your larger tools, router table, etc. to 4" ports... including fitting a hood to your drill press.

As for your smaller, hand-held tools I'd forget all about the DC; they'll just choke it down and make it inefficient. These are where your shopvac is the better choice. It's what these tools are designed for, after all! Make yourself a Sturdee dustbucket or similar (search on these forums) if you want a mini-cyclone on the shopvac.

And with the pennies saved by not going to a 6" fixed main, you could buy yourself an overhead air-filtration unit to get rid of the really fine dust!

I'm no expert on this, but opening up to 6" would only work if you have a dust extractor, not a shop vac (which is usually only 2-2.5"). From my reading of your post, you won't be looking at getting a dusty for a few years, so perhaps it is best to focus on maximising the extraction efficiency of your vac setup (better collection points, quality cyclone, etc) rather than expanding port sizes to 6". I don't think a vac will be able to move enough volume of air to lift many of the chips out from, say, a jointer or thicknesser. Vacs run high pressure, low volume, whereas dusties are the opposite - high volume, low pressure.

But as I said, I'm no expert on this so I could be all wrong. Best to get advice from those in the know on these forums. FWIW, as soon as I return, I will convert to 6" ducting from a fixed dust extractor, and probably purchase the DIY Dust Deputy or similar to add to a cart for my shop vac. The vac will move between different machines, while the dusty will live in a tiny alcove separated from the rest of the workshop to avoid the dust recirculating.

Trav

Originally Posted by jack620

Hi,
I've got a DIY Dust deputy+Vac for the "dust" making tools like sanders, routers, etc. and a hare & forbes dust extractor for the bigger machines. I use a 4m length of flexible 4" hose and wheel the H&F extractor out the rollerdoor to keep the fine dust out of the shop.

Unfortunately that won't be very effective for invisible dust which hangs in the air for hours. Venting a DC outside a shed creates a low pressure region inside the shed. If the DC is sitting just outside a large doorway it is too easy for the invisible dust being emitted in spades by the DC to just drift back into the shed under the pressure gradient. The DC needs to be vented in such a way that there is no opening back into the shed along the wall where the DC is located. Fresh air intake into the shed should be via a large opening on the opposite wall to where the DC is located so cross ventilation is obtained. It may look perfectly OK but remember most of these particles are invisible.

RSG, It doesn't matter what you use, but if you want to capture fine dust, as long as the 1000 cfm and 4000 fpm is achieved at source. This is simply not physically possible possible with a single 2" or 4" ducting or flexy, the ducting must be 6" just to pull 1000 cfm in most situations. Two 4" flexys going to a 6" duct is a bare minimum to achieve this.

Most shop vacs just fill sheds with fine dust and need to be backed up with a large volume DC that can clear a shed of fine dust in short order. I have an overhead filtration unit but opening all dust collection ports on all machines and turning on the the Big DC is more efficient at clearing the shed than the overhead filter. The overhead filter is trying to do this from one collection point whereas the DC ports are spread through out the shed and collection is done from many points in the shed.

Okie dokes. Interesting input thus far

So while I'm trying to organise a chat with Mini (which is a lot easier and quicker than foruming) I've continued reading and smashing information against my head and begrudgingly accepting that what I'd like to achieve just won't happen with a shopvac driven system.

Since I've been an exceptionally good boy and haven't killed anyone this year (plus a bit of poor mathwork and reminding myself that the cheap option usually costs me more in the long run) is there good value/reason to putting Santa in a wristlock for this DC system given my shed/container and machinery from the first post:

- Carba-Tec® 2hp Economy Extractor : CARBA-TEC with the expectation of adding a Pleated Filter Cartridge - to suit FM-300 : CARBA-TEC when I can afterwards.
- Putting a cyclone (homemade (cone or Thien) or low-end Carba-Tec® Dust Deputy : CARBA-TEC, or the very interesting looking Mini CV06 Home - Mini CV06) in front of it for the main chip collection.

Question: Do I still need a vac for the first stage cyclone or does it just sit in series with the bigger DC?

If that rig would work well with large chips and the fine "death dust" I could justify laying permanent 6" ducting and expanding/doubling the TS and thicknesser ports to 6". And could easily vent outside away from the shed doors.

I forgot to mention originally that all of my gear is on wheels and it's actually very easy to move machines from their resting places against the walls to a dust collection point. (Probably easier moving the machines than a vac with all the hoses.) So if I'm clever I could have a dust system setup out of the way (possibly outside) with one or two short lengths of permanent ducting along the roof with short ends of flexi coming down to where the machines would be moved to.

Am I getting closer to an efficient chip and dust collection system and healthier workshop in a bang for buck scale on a tight budget?

Originally Posted by RedShirtGuy

- Carba-Tec® 2hp Economy Extractor : CARBA-TEC with the expectation of adding a Pleated Filter Cartridge - to suit FM-300 : CARBA-TEC when I can afterwards.

Even though the spec says it can do 1200 cfm that will be with for the impeller only with no ducting and no bags. Once these are attached it will probably only make ~600 cfm. The killer with this DC is the small input at the impeller and more significantly the small diameter flexy between the impeller and the bags. DCs that use small diameter flexy between the impeller the bags are never going to reach the 1000 cfm in practice. This two bag unit is about the only 2HP unit that can reach 1000 cfm in practice. It also has a impeller input manifold that can be removed and replace with a single 6" intake.

"Am I getting closer to an efficient chip and dust collection system and healthier workshop in a bang for buck scale on a tight budget?"

I think the answer to that is...no, not really.

This looks like a reasonable budget choice - Carba-Tec 2hp and 3hp Two Stage Cyclones : CARBA-TEC ....if your budget stretches to $2k, that is.

The mini cyclones are designed to work with high velocity, low volume sources like vacuum cleaners; adding them to a low velocity, high volume source will play merry hell with the cyclone or the extractor, with either ending up as a loss of extraction efficiency.

Stick with the shop vac and add a ceiling mounted air cleaning thing. DIY it to save money... Kevin Brady - DIY Dust Control Devices

Originally Posted by Master Splinter

Stick with the shop vac and add a ceiling mounted air cleaning thing. DIY it to save money... Kevin Brady - DIY Dust Control Devices

I wouldn't be paying too much attention to that site. I start to worry when I see someone using 50 ft of 4" flexy, 4" ducting and worries about earthing on a hobby level DC. A simpler and more effective option than mucking around with home made room filters is to fit a couple of bathroom type air extractors and/or an extra window and door to help with cross ventilation. Of course none of these solution pick up the chips but there is always a broom.

Another question that arose tonight from comparing gruntier machines against my wallet...and I'm sorry to be so budget tight in my queries...I know what a pain it can be dealing with someone like me who wants the world for mere belly-button lint...but my situation is what it is

Simply put, what is it with this machine (https://www.machineryhouse.com.au/W329) that makes it cheaper than the 2 bag system BobL showed? It's a higher HP and CFM and same 5 micron ability but considerably cheaper so I'm wary of it being built with a dodgy motor/blower. It can also take 1 micron filters (https://www.machineryhouse.com.au/W328) that I can't see available for the CT machine.

****At the time of posting the whole MachineryHouse site is having a hissy fit and only showing a "call for price" amount for a lot of products - The DC was $517 inc. GST according to Google cache****

I'm inclined to email H&F and ask if what looks like a plate around the outlet can be removed (looks like it screws to a lip from the pic) and modified to suit a 6" single or double port. For them to answer the modification aspect properly, and because I haven't seen anything to indicate whether or not it's a problem, is it necessary for the impeller blades to NOT be visible within or too close to the diameter of the inlet hole and giving a "clear" draw? Meaning, should I also be asking them about the distance between the middle of the impeller to inner end of the blades to determine how large a hole I could make? (Presuming it's not an airfoil)

Thanks to the responders. I truly appreciate your help on a subject I'm struggling with. Hopefully by the end, others can get something useful out this; like a realistic look at cost for a "safe" system at the least.

The 2300 cfm rating for that unit is impossible because the 1950s type design is too inefficient - in practice I'd say it will be lucky to be around 800 cfm. Specifically, the intake opening to the impeller after the the 3 x 100 mm ports (it might be 125 mm) is just too small. This opening has to be 150 mm or fitting 150 mm ducting is a waste of time. The square cross section ducting between the impeller and the bags is also very inefficient and will be no better than 100 mm circular ducting. I have seen several of the units (I have the 2HP version) and they are so poorly made that it leaked quite badly and needed considerable attention to stop them leaking dust. They are reasonable efficient chip collectors but that's about it.

The reality is that manufacturer supplied CFM ratings on DCs are meaningless unless they specify what operating pressure can be generated and what sized ducting that the systems can be effectively connected to.

Thanks for that Mr B.

The ratings aren't only meaningless, they're practically false advertising when they don't specify where the rating, if it's even true in the first place, has been measured. I don't think it's unreasonable for people to expect that the rating stated means right at the inlets or inside the bags.

It really shows what Bill talks about when he says that manufacturers are pulling dodgies.

I had a good chat with Mini this morning and while I'm no closer to having the system that I want/need, he did provide a bit more info on certain things and came out with an interesting idea on a shortened false ceiling in the container to act as a wide duct with a bank of extractor fans to help move the air. It's the starting point for some more research anyway.

After all this, it seems that the realistic budget for a GOOD chip AND dust collection and extraction system (off the shelf) is around $2500-$3000 at least...something that's well out of my range for the time being. So I'll just have to go back to home made chip collection solutions to at least save on clean up time; which is better than nothing at all I guess.

I've come out of this with some good knowledge and a better idea of what I should be looking for, so thank you all once again.

Look out Market Place threads, I'm watching you

Originally Posted by RedShirtGuy

Thanks for that Mr B.

You are welcome.

The ratings aren't only meaningless, they're practically false advertising when they don't specify where the rating, if it's even true in the first place, has been measured. I don't think it's unreasonable for people to expect that the rating stated means right at the inlets or inside the bags.

They are not all like that - the clearvue specs are clearly listed on their webpages

I had a good chat with Mini this morning and while I'm no closer to having the system that I want/need, he did provide a bit more info on certain things and came out with an interesting idea on a shortened false ceiling in the container to act as a wide duct with a bank of extractor fans to help move the air. It's the starting point for some more research anyway.

That does sound like a good idea.

Keep an eye out for any auctions as a source for fans/blowers, also if you know or make a few calls to air con installers you might be able to pick up for nothing the fans out of the dead reverse cycle units, (you want the axial flow ones like a propeller) will need a sparky to put a plug on! the fan out of old window rattlers can be useful as well or the tip shop at the local tip, not sure where you are tho, the downside to this tho is the stuff for nothing usually requires some effort on your part to make it function as required but then that's half the fun


Pete

I went to my faaaaaaavourite scrap and seconds metal yard yesterday to trawl through the machinery there looking for, at least, impellers. I came pretty close with a few 14" by they were cast and already chipped and damaged. I asked the blokes there if they had a secret stash but basically what I saw was all they had.

It turns out that I have an assosciate who works at Fantech on-line ventilation fans & noise control product catalogue so I might see if I can put him onto the case for me as well.

But after hours and hours and hours of hunting, it seems that (like others have found) it's damn near impossible to get an appropriate single phase motor for Australian power without having to 'tweak' the voltage or rack up the speed with pulleys...and for the cost it's almost worth just buying something from overseas.

There have been a few interesting motors from Australian manufacturers/distributors CMG and WEG, but I think they're still not quite what we need for a BP system

The hunt continues.