Advice on dust extraction & ducting - CamVac & Cyclone?

[Sam Newman]

Hi all,

I’ve been lurking a bit, and trying to piece together the information I need from threads here and elsewhere on the interwebs, but I’ve come to a bit of an impass and I could do with your help!

I’ve recent brought a very nice small table saw, which has 100mm dust extraction port. After jury rigging a connection with my existing Titan shop vac & dust commander setup it’s pretty clear that my dust extraction finally needs to be stepped up.

I’m strongly considering getting a two motor CamVac CVG286 vacuum extractor (likely the 2000w 35L model). The rationale is that the table saw is the biggest thing I’m likely to have for a while. I’ve got no plans for turning, planing or any of that stuff, and most of my dust extraction needs are for the table saw, mitre saw, sander and track saw (a router table will follow). So mostly we’re looking at fine dust rather than large chips.

I’ve got all of this stuff in a fairly small place in my garage. I’m thinking of connecting the CamVac to a short run of ducting, with blast gates for the table saw and mitre saw, with a hose outlet for the other devices. The run of ducting I’m thinking of is likely to be 4m or less. Given the limited space, I’m also looking for a setup that is as compact as possible. Outside venting *might* be possible, but it would likely be tricky.

I’m thinking of 63mm/2.5” ducting - this would mean stepping down the 100mm outlet from the CamVac, but would reduce price of all the fittings & fixtures. The challenge I have is the cyclone. The current one I have is only 50mm - it doesn’t seem to make sense to me to step the CamVac down to that, only to increase it back up to 63mm. Looking around though, the options for cyclone separators that take 63mm/2.5” are pretty thin on the ground. Given the relative pain of keeping the CamVac filters clean and emptying the thing, a cyclone seems like a pretty good idea.

I may put the ducting off for a bit, and just plug the CamVac directly into the table saw for the moment while I make the other decisions, but I’d love thoughts generally on the suitability of the CamVac for a small ducted system like the one I’m describing. I can of course do a ducted CamVac setup and wait on the cyclone till later if it’s a case of waiting for the right eBay item to come up.

So I have a few questions for you fine folk:

1. Does a ducted setup in general sound ok for this situation, putting the cyclone separator to one side for the moment? If so, do you see any problems with stepping it down to 63mm vs 100mm?
2. Any idea where I could source a cyclone separator for 63mm/2,5”?
3. Anything else about this setup seem crazy?

Many thanks,

Sam

 

[cammy9r]

Hi, if everything is 100mm then use 100mm ducting or as i did, soil pipe. Make your own blast gates it is pretty simple. The soil pipe is not 100mm it is ~110mm but i used stop ends for one side of the blast gate and 100mm extraction fittings from gate to tool. I will see if i can go take a photo shortly.
It all works well enough for me.

 

[sunnybob]

its not very difficult to make a cyclone from a road traffic cone.
But the full size cones are fairly flimsy and compress easily under a good suction motor so need a supporting framework.
I have a 3/4 sized cone using 75 mm connections without any support and it works extremely well with my 62 mm piping system.
100 mm will always be the best, but if price matters then 62 mm is viable.

 

[cammy9r]

Some pics of my setup.

 

[cammy9r]

Another one.
Edit: It was £114 for the pipe and fittings. Blast gates made from offcuts.
These pics where taken as i was putting it all together, there has been minor tweeks over the last few years.

 

[Sam Newman]

Thanks for the feedback! I'll let you know how I get on.

 

[Sideways]

There's a simple hint in the design of your machine.
It has a 100mm dust port.
This tells you you should pipe it in 100mm and attach it to an extractor that has a 100mm port.
But beware of extractors like the Numatic NVD750 that have a 100mm port but actually can't generate enough airflow to operate properly with a 100mm system. They are great at 50mm-63mm though.
The camvac (unless you have the 3 motor model) is likely to be a marginal performer with this tablesaw. Not because it's a bad machine but because it's not designed to shift high volumes of air. Tablesaws are often poorly designed internally for dust extraction and need a high airflow rather than high vacuum.
Chances are you really need a bag type extractor, which of course are irritating because they leak the fine dust and take up far too much space.
In a small shop, everything is a compromise and your tablesaw dust extraction is at risk of becoming another one....

 

[woodbloke66]

It's quite feasible to use a twin motor Camvac with a cyclone as I've done here:

The cyclone is the Dust Deputy Super from Toolovation and this is one that was recommended to me by somebody (forget his name, but a nice bloke) when I spoke to him on the 'phone a few years ago. He knew his stuff about cyclones and mentioned that the twin motor version would be fine with the DDS. For a collection bin, I've used a large 200l (or thereabouts) water butt fitted with a pressure relief valve (dead easy to make)
All the ducting is the standard 100mm stuff that you can get from many suppliers; this came from Ax together with the aluminium blast gates. All joints sealed with a turn of duct tape and some cable ties for good measure.
It extracts from the p/t, lathe, disc sander, floor 'gulper', drum sander and large Ax bandsaw but I don't know how it would fare with a tablesaw because (as others have said somewhere) they're notoriously difficult beasties from which to suck out the dust - Rob

 

[sploo]

Sam,

Bill Pentz's site is very useful (though wordy) for calculating suitable ducting and cyclone requirements.

Many years ago I built my own ducting for an extractor that vented outside (http://spikyfish.com/DustExtraction/) having since moved and unable to use the DIY ducting parts in my new garage you'd be welcome to them if you're anywhere near the north Leeds/York area.

 

[Inspector]

There's a simple hint in the design of your machine.
It has a 100mm dust port.
This tells you you should pipe it in 100mm and attach it to an extractor that has a 100mm port.....

Actually that tells you the manufactures are fitting the machines to decades old standards for chip and dust you would have to sweep up. It won't meet the newer specifications to collect dust that you can't see. If you are happy collecting "clean up dust" then 100mm is good enough but you'll still need to wear a respirator to keep fine dust out of your lungs.

Pete

 

[Inspector]

Sam,

Bill Pentz's site is very useful (though wordy) for calculating suitable ducting and cyclone requirements.

Many years ago I built my own ducting for an extractor that vented outside (http://spikyfish.com/DustExtraction/) having since moved and unable to use the DIY ducting parts in my new garage you'd be welcome to them if you're anywhere near the north Leeds/York area.

Agreed about Bill being wordy but he has to repeat himself since most people cherry pick a portion of the site and would miss important bits.

I like your ducting and I am going to make something similar but bigger and heavier to handle the 5hp cyclone I have. Nice to see others have the same idea.

Pete

 

[Sideways]

There's a simple hint in the design of your machine.
It has a 100mm dust port.
This tells you you should pipe it in 100mm and attach it to an extractor that has a 100mm port.....

Actually that tells you the manufactures are fitting the machines to decades old standards for chip and dust you would have to sweep up. It won't meet the newer specifications to collect dust that you can't see. If you are happy collecting "clean up dust" then 100mm is good enough but you'll still need to wear a respirator to keep fine dust out of your lungs.

Pete

We're both oversimplifying and only telling part of the story
It just shows that dust extraction is a little complicated and well worth both reading up and (unfortunately) experimenting.
Most tools have a minimum airflow needed to extract properly. It will be in the manual (with luck). Big machines tend to leak air from all sorts of places so they need a big airflow to pull the dust through the machine into the extraction outlet. Big flows tend to mean a certain type of extractor and big pipes.
Machines like the camvac and NVD750 have much better suction, have great fine filters and work well with cyclones and narrowed piping as they have suction to spare which matters. They work great with well designed machines that have well sealed cabinets and close fitting extraction guards, but they don't move as much air and without adequate airflow for the machine in question (of which yours may or may not be one) some dust may never even make it into the system.

Here's a suggestion. Get your existing titan and get your household vacuum cleaner. Together they will be about the same as a twin motor camvac. Stick both their hoses into the 100mm port on your tablesaw and shove some rags tape or a towel around them to make a seal. Run it like this. If it works then buy with confidence. If you get a load of dust still dropping out of the bottom of the machine or spraying forward off the top of the blade, then you will know what to expect.
Cheers.

 

[poodelek]

Hi everyone

I have a similar situation to Sam's. My table saw dust extraction port is 100mm but my cyclone has only 50mm inlet and outlet to the shop vac.
I am not considering at the moment upgrading the cyclone but I want to make a little more substantial dust extraction system.
I know that ideally you should go for as large diameter as possible but will it be beneficial in any way to have 100mm or even 63mm if it is reduced to 50mm before entering the cyclone?
Or going even further... will in this situation a larger diameter of the hose not cause a pressure drop and less efficient dust collection from the table saw?

 

[Sheptonphil]

Another one.
Edit: It was £114 for the pipe and fittings. Blast gates made from offcuts.
These pics where taken as i was putting it all together, there has been minor tweeks over the last few years.

I think this might work in my new workshop. I’ve a separate room for the extractor and was looking at either flexible pipe as before, or going soil pipe. Why the underground version as against the grey which is cheaper?

 

[DBT85]

Another one.
Edit: It was £114 for the pipe and fittings. Blast gates made from offcuts.
These pics where taken as i was putting it all together, there has been minor tweeks over the last few years.

I think this might work in my new workshop. I’ve a separate room for the extractor and was looking at either flexible pipe as before, or going soil pipe. Why the underground version as against the grey which is cheaper?

When I looked yesterday on toolstation underground brown was cheaper than grey or black. I think black and grey were £24 for 6m of pipe compared to £18 for poo brown.

Just a few days ago John McGrath did a video about putting his new soil pipe system on. He used black pipe as it was the same price for him.

https://youtu.be/812Ez9OT0As

 

[sploo]

Another one.
Edit: It was £114 for the pipe and fittings. Blast gates made from offcuts.
These pics where taken as i was putting it all together, there has been minor tweeks over the last few years.

I think this might work in my new workshop. I’ve a separate room for the extractor and was looking at either flexible pipe as before, or going soil pipe. Why the underground version as against the grey which is cheaper?

Just be aware re static buildup + sparking. Worth having a grounding wire running through. Also have plenty of access joints or the odd clear section. You will at some point get a blockage, and dismantling large sections of pipework to find the problem ain't fun.

 

[sploo]

Hi everyone

I have a similar situation to Sam's. My table saw dust extraction port is 100mm but my cyclone has only 50mm inlet and outlet to the shop vac.
I am not considering at the moment upgrading the cyclone but I want to make a little more substantial dust extraction system.
I know that ideally you should go for as large diameter as possible but will it be beneficial in any way to have 100mm or even 63mm if it is reduced to 50mm before entering the cyclone?
Or going even further... will in this situation a larger diameter of the hose not cause a pressure drop and less efficient dust collection from the table saw?

Air at low pressure kinda behaves like water (basically incompressible) so if you use a HVLP extractor and throttle the size by attaching a (say) 100mm pipe to a 50mm port on a machine then you really damage the air flow.

Conversely, a shop vac should pull pretty well; though isn't designed for carrying large amounts of air (LVHP). The problem in going for a wider-than-designed pipe is that the air speed in the pipe will drop, and may then be unable to carry the dust.

Whilst larger diameter pipe is "good" (with an appropriate extractor) if you can I'd just use the cyclone close to the table saw (with a 50mm pipe) and adapt it to the 100mm port at the machine. It's unlikely to work really well, but it will probably do some good.

 

[DBT85]

Someone really needs to make up a 3D printable 100mm cyclone.