# Table saw dust extraction



## Karl (16 Mar 2011)

I've decided to try and do something about the dx on my Xcalibur ts.

First off, some pics







Dust is currently extracted via a 4" outlet at the very bottom of the machine






You can see the cavernous area around the motor and blade for dust to fly around before being extracted.






One problem comes when swinging the cradle for angled cuts.






My initial thought was to block up the existing d/x hole and put a new 5" one right behind the blade on the back of the machine






Also find some way of blocking up all the silly gaps between the cabinet and the cast iron top (those are my fingers in the pic).






Anybody got any good ideas on how to treat the swinging cradle - I want to reduce the internal volume of the cabinet by fitting a false floor/blade shroud.

Any comments welcome.

Cheers

Karl


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## p111dom (16 Mar 2011)

I'd be inclined to make a Formica faced hopper reduce the internal volume of the cabinet and to direct dust to the port. My older style jet super saw has this and it works really well.


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## Mike.C (16 Mar 2011)

Hi Karl, the following are not my work, but I hope that they will help you.

First of all your silly gaps, well these could also be made to fit the upper ones



These other ones could deal with the upper and lower dust











Lord Nibbo also came up with a very good idea. viewtopic.php?t=20038

What about making a box that wraps around the blade and cradle but not the motor (over heating) and has a chute that points towards an internal extraction pipe.

HTH

Mike


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## ondablade (16 Mar 2011)

I'm guessing the issue with allowing the dust to drop into the bottom of the cabinet has to be that it inevitably creates a situation where collection is going to be reliant on having some sort of hopper where gravity reliably drops the chips and dust into the duct - it would probably otherwise take an enormous airflow volume (cfm) to give enough airspeed to gather up the dust over such a large area. Air leakage into the cabinet in areas that don't help much will up the ante even more.

Many makers seem to go with a fairly close fitting hopper/chute under the blade - this should give decent air velocities at smaller volume flow rates due to the much smaller cross section, and as a result of both this and the layout more or less immediately capture dust thrown off the blade.

I'm looking forward to having a little play with my own set up when my Hammer saw is up and running in the coming months - a pet theory is that (a) it makes sense to clear the dust from the tooth gullets before its carried back up over the table surface at the backside and flung into your face or the blade guard, and (b) that if the air inlet into the chute was organised so that it directed the air it takes in at right angles across the teeth it might be very effective at clearing the dust from the gullets.

The game would then be to as far as possible seal the chute, and to size these inlet(s) so that they leave just enough negative pressure in the duct to give decent clearance down through the gaps around the blade - without so much suction that it causes problems in sliding the workpiece...


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## matt (16 Mar 2011)

Re the gaps between the top and the casing... I just pushed pipe insulation in to mine - does the job.


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## Steve Maskery (17 Mar 2011)

This is timely, Karl, I'm looking at exactly the same problem.
My saw has to be mobile, so permanent DX is not an option. I have a hole in my guard to take a hose, but I rarely use it, not because it doesn't work, it's quite good, but because the hose is a bit inconvenient. Laziness, if you like.
I like the shroud idea. I had thought of a piece of pipe which hugs the blade, but I don't see how I could mount it.

I might just not fight it at all, but make a liner that I can just lift out and tip into the bin.

I look forward to seeing your progress.
S


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## Karl (17 Mar 2011)

Thanks for all the input guys. This job would be a hell of a lot simpler if the blade didn't tilt :lol: 

Anyway, a little more digging round this morning revealed a [black] metal channel mounted to the cradle in front of the blade - presumably to stop crud being ejected through the front of the machine where the winding handle is situated.











Remove this and you've got a pair of threaded mounting points 






And with the blade back in-situ.






So my current thinking is that some kind of scoop could be connected to this mounting point, connected directly to the d/x port, perhaps by a flexi hose which would overcome the problem of flade tilt. This would capture the dust directly from the front of the blade. I've also found a guard for above the blade which will be mounted directly onto the riving knife. This has a d/x port on top.

Cheers

Karl


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## ondablade (17 Mar 2011)

Those holes look promising provided the bracket they are in tips with the blade Karl.

Perhaps a fairly close fitting box/enclosure that tips with the blade rather than a scoop that may leak and not direct the airflow very well - here's how Felder do it on their 900 series saws: http://www.felder.ie/ie-en/products/pan ... &zoom=true (click on the picture of the saw spindle) Go to the Hammer product pages on the same site, look up the K3 Perform panel saw and check out the similar drawing for a simpler variant.

Getting the enclosure close to the blade will by upping the air speed up the effectiveness of the extraction, (but not such much that it chokes the air flow) while the shape and positioning of the inlet(s) and outlets will determine the direction of air movement and avoid dead spots.

Don't forget that the enclosure needs to let in/through enough air to give enough air flow in the duct to properly transport dust and chips back to the dust collector too. ( the 3,800 fpm in the duct I've been talking about in other posts) 

As above positioning the inlets correctly may help clear dust from the blade gullets - and it seems to me that the one thing you don't want to do any more than can be helped is to allow the blade to carry dust back around and up over the table again as by definition you can't properly contain it/stop at least some of it being flung out once up there with any guard that you can also work around...

In an ideal world the top guard probably shouldn't have a lot of work to do...

PS It's just one of many options, but it's not too hard to make up a disposable one use mould from sheet metal, card or foam board and the like to make a housing like that in glass fibre if you are not too bothered about it being finely finished. Wax it well, and coat it with a PVA release agent, and use precisely the recommended amount of hardener if it's polyester resin as it can otherwise warp and distort. Fill any sharp corners (so they end up a decent radius) with a finger applied fillet of Isopon or something to ease the eventual lay up, and use several layers of a lightweight open weave (so it conforms easily) cloth or over a gel coat.


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## Karl (17 Mar 2011)

Hi Ian

Yes, it does tilt with the blade, although it doesn't rise and fall with the blade. #-o 

Thanks for the Felder link - very interesting. For everyone else, here's what it shows






Cheers

Karl


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## Mcluma (17 Mar 2011)

That is also the way it workst on my EB PKF255 

although mine is not build of that heavy cast iron, but from simple 3/4m stell plate


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## 9fingers (17 Mar 2011)

Karl,

I've got the table top off my Xcalibur at the moment to do a modification* (10" but I think yours is the 12") and I've got nothing like that amount of dust accumulating in mine. The biggest problem I find is slivers falling down and blocking or entering the DC port.

It also throws a fair amount out at groin level either from the gap betwixt table and casing or through the height adjustment hole.

I might try and block those gaps whilst I have it in pieces.

*I'm fitting a DRO to indicate the blade height as i do a lot of dado and joint cutting on my saw although I realise that is is not to everyones taste.

Bob


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## dickm (17 Mar 2011)

Probably not transferable, but I made a new under table guard for my Lurem (the blade originally only had the most vestigial guarding, and the side of the saw was completely open). This rises/falls and tilts with the blade. It then has a 2" exit on the bottom front corner, connected via a piece of flexible hose to an outlet on the side of the machine. Doesn't collect everything, but helps a lot as I realised this afternoon when the extractor hose had come disconnected from the outlet. Wondered why there was so much dust suddenly flying around.
Obviously not in the Felder league, as it was fabricated out of 1mm steel sheet, but it's do-able.


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## Bluekingfisher (18 Mar 2011)

Not sure if it will be any help but to reduce the dust being thrown out and increase dust extraction at the same time, I read an article whereby the author had used a draught excluder type set up (the hairy brush type used behind letter boxes). He installed it behind the slot for the height and slide adjustment wheels. The adjustment bars of the wheels slide easilt along it's desired path with no or little resistance from the excluder. He seemed quite pleased with it.

Just a thought


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## Karl (18 Mar 2011)

Bluekingfisher":35fmgr2s said:


> Not sure if it will be any help but to reduce the dust being thrown out and increase dust extraction at the same time, I read an article whereby the author had used a draught excluder type set up (the hairy brush type used behind letter boxes). He installed it behind the slot for the height and slide adjustment wheels. The adjustment bars of the wheels slide easilt along it's desired path with no or little resistance from the excluder. He seemed quite pleased with it.
> 
> Just a thought



Thanks - I had that one mentally stashed away and was planning on fitting something similair. 

Cheers

Karl


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## 9fingers (18 Mar 2011)

We are thinking on similar lines. I have a length of the bristle draught excluder here in readiness for blocking the arc round the height adjuster shaft. That is the next job whilst I have the table off the saw.

Bob


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## 9fingers (18 Mar 2011)

I made good progress this afternoon. SWMBO went out for the afternoon - was there a connection I wonder????

First off a couple of pieces of brush strip formed into arcs to suit the slot in the Xcalibur casing.

Notches cut about every inch to allow the strip to be bent to fit a couple of MDF templates of the the slot curves.











There is about 6mm clearance inside between the casing and the trunnion castings - just room for the strip to be screwed in place






The casting that extends through the slot serves only to hold the pointer but is quite thick and will permanently distort the bristles so I machined in a pair of slots for the bristles to run in






Handwheel refitted and all is back together






Ideally I would have liked to have longer bristles to close the slot completely, however this was the only size strip I could get at the time which is 15mm.
However, Toolstation are now selling a 25mm strip item no 57368 which might be a better choice if you want to do the same modification.
I think that reducing the slot from 45mm down to about 10mm as well as other gaps I will block should increase the vacuum inside the cabinet sufficiently to prevent dust being thrown out of the slot.

I've still got to finish other mods to the saw before I can put the table back on and try it out in anger.

Hope this is of interest

Bob


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## Karl (19 Mar 2011)

Thanks Bob - very helpful. Although machining a coulpe of slots on the pointer casing may be more difficult for me than you  

Cheers

Karl


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## 9fingers (19 Mar 2011)

Hi Karl,

Cast iron is quite soft stuff and you could cut the slots with the edge of a file. They do not have to be precise in any way.

Bob


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## Karl (23 Mar 2011)

Just a quick update. One thing I needed to sort out was above table guarding (and re-fit the riving knife). For those who don't know, my original guard was destroyed in my Brown Trouser Moment. It was rubbish anyway :lol: 

I saw a Dewalt blade guard on e-bay and bought it - £18 delivered. A bit of work with a hacksaw and re-position the mounting hole on the riving knife and i've now got a new blade guard fitted, complete with above the table dust extraction.











I drilled an elongated hole in the riving knife for the guard to slot into. As you can see, even at full depth of cut, the guard can't touch the blade (unlike the last one!).

Anyway, i'll be cracking on with the under table extraction in the next few days.

Cheers

Karl


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## Chems (23 Mar 2011)

That guard looks like it might actually do a good job, right sort of shape.


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## 9fingers (23 Mar 2011)

Karl,

In the end I blocked all gaps round the underside of the table, the arc shaped hole on the back of the cabinet and the louvres on the motor cover. The area of the remaining gaps came to about 60 sq cm and the dust port is 78 sqcm so fairly well matched.
The dust extraction is very much improved now.

Bob


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## Karl (23 Mar 2011)

James - that's what I thought! At £18 I thought it was worth a punt.

Bob - I saw your mods over on TWH. I think one of the main problems is a lack of suck at the extraction end. I'm going to invest in a bigger extractor. I think this will solve the majority of the problems. If it doesn't then it is back to plan A of the under blade extraction.

Cheers

Karl


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## ondablade (23 Mar 2011)

Sounds good guys. One issue I'm not too sure about on top guards is that in the US Shark (whose product gets good reviews http://www.leestyron.com/default.php ) go for a very wide top guard, and also a large 4in duct connection with a commensurate 400 cfm approx high airflow.

Felder on the other hand go for a relatively narrow one, at least on my K3 saw anyway http://www.felder-tooling.co.uk/8-420-7 ... 1-1-0.html - it looks quite similar to the De Walt item in your picture Karl, and is maybe another source of guard for retro fitting.

I can't see why a wide guard adds very much when almost all of the chips the top guard is required to collect tend to shoot off at tangents to the saw teeth - in the plane of the blade. I haven't got the Hammer running yet, but this was what my prior Robland seemed to do.

My thinking is that if enough air is moved through the guard then it'll pull any loose dust etc in from the sides anyway - it's in the end not the width of the guard that matters, but the size of the low pressure area created around the blade. Also of course that the profile of the top surface should be such that it hooks back a bit to capture chips.

One change I'm for this reason planning to make to the Felder guard is to glue on a 4in dia stub for a 4in duct, this because much like the De Walt the stock stub is small and restrictive - possibly 2 1/2in? This can probably be accommodated on a narrow guard by making the stub from a length of acrylic plastic tube (presuming the guard is acrylic) and flattening one end (after heating) to form an elongated oval. The cross section of the oval will be similar to the 4in duct, but narrow enough to mate nicely with a lengthened slot in the top of the guard. Bostik Tensol 70 (a two part adhesive used by plastic fabricators) is excellent for bonds like this on acrylics..

Does anybody have any views on the usefulness or otherwise of a very wide guard like the Shark item?


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## Steve Maskery (23 Mar 2011)

The advantage of a wide guard is the ability to guard satisfactorily at a 45 deg tilt. If the guard is narrow, a 45 deg tilt becomes difficult at any depth.
I agree the Shark looks good.
S


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## ondablade (24 Mar 2011)

Thanks Steve. Does a narrow guard make sense when mounted on a riving knife (like on the Hammer saws) do you think?


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## eoinsgaff (24 Mar 2011)

I'm not sure if this is much help but, in a Fine Woodworking article, the writer used what appeared to be fridge magnets (rectangular pieces the size of playing cards) to block the slot in the side of the saw where the angle adjustment moved. They were just moved along by hand when changing the angle. Maybe one cut to fit around the adjusting wheel would give a really sound seal.

I hope I'm not too late with this.

Regards

Eoin


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## Steve Maskery (25 Mar 2011)

ondablade":2m9rmkm0 said:


> Thanks Steve. Does a narrow guard make sense when mounted on a riving knife (like on the Hammer saws) do you think?


Well I suppose the bigger the guard the more likely it is to foul the fence if the workpiece is narrow. I don't really know if it makes any other difference. I'll give it some thought.
S


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## mtr1 (25 Mar 2011)

I don't know about your saw's, but when I rip/edge say a couple of mm's off, the dust seems to come on to the table at about 45degree to the blade. Paul-Marcel has done a few mods to deal with this at 3.26 in.


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## Karl (26 Oct 2011)

I know this is an old thread, but I finally got the problem fixed. 

I ended up taking the easy way out and going for more suction rather than complicated mounting of extraction parts. So I bunged up all the holes around the top of the table saw with a mixture of loft insulation and duck tape.












I also used Bob's trick of draught excluder for the handle to move through when tilting the blade through 45 degrees - note the extensive use of duck tape!






Finally, I cut a new hole for extraction. I've upgraded my ducting to 6", and the original port was 4" (actually less - the internal section was blocked off by part of the cabinet construction; I reckon it was only about 3"). I also mounted this on the rear of the t/s as this is more convenient for use with my extraction set-up.






Results? Highly impressive - you can hear the suction whistling through the holes around the blade on t/s top. Test cuts on a few pieces of MDF this morning showed much improved extraction, and that was without the crown guard extraction running. 

Cheers

Karl


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## Bluekingfisher (31 Oct 2011)

Karl,

What did you use to cut the round hole in the rear of the cabinet. I will shortly be tackling my dust collection and need to move the dust outlet port to the back of the saw. Any tips would be appreciated.

David


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## beech1948 (31 Oct 2011)

The pictures are not showing up for me on this one thread.
Any ideas at all folks.
All I get is a reference to photobucket.com and thats it.

regards
Al


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## 9fingers (31 Oct 2011)

Must be a break in the string from you to Photo bucket? I't all OK here.
Try control F5 to reload page

Bob


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## Karl (31 Oct 2011)

Bluekingfisher":27d44bgl said:


> Karl,
> 
> What did you use to cut the round hole in the rear of the cabinet. I will shortly be tackling my dust collection and need to move the dust outlet port to the back of the saw. Any tips would be appreciated.
> 
> David



Hi David

I just used a metal cutting blade in a jigsaw. Slow the speed right down. If you're using smaller extraction pipe (mine is 6") you might need to make relief cuts before going for the final cut as the radius may be too tight for the thickness of the blade.

Cheers

Karl


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## Bluekingfisher (31 Oct 2011)

Thanks Karl, I can already feel my pulse racing at the thought of cutting into the cabinet of my saw. I'll make sure I buy some quality blades and some mini grinding disks for my die grinder.

One other point....my current outlet is on the left side of the saw (looking from the front) Like you having it emerging from the back will save a lot od space and duct work. The only thing is, there is an internal sloping right to left shelf to assist the dust towards the dust port. Is this similar with your saw and if so did you alter it towards the back to suit your new outlet??


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## Karl (31 Oct 2011)

Excatly the same situation with my saw David. I just cut a piece of 12mm mdf to fit inside the t/s which sits on the floor and creates a "valley" - the new d/x port sits at the bottom of this valley.






Nothing fancy - just seal it up with caulk and duck tape. Be careful to make sure that there is enough clearance for the motor to still swing past into 45degrees.

Cheers

Karl


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## Bluekingfisher (31 Oct 2011)

Thanks for getting back Karl, if memory serves the existing sloping tray in mine is held in place by four small bolts. As I sit here at work I am hoping they have hex nuts rather than pop rivetts, I'll double check tonight when I get home.

Thanks again for the feedback, much appreciated


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## Noel (31 Oct 2011)

Bluekingfisher":10aqfzkc said:


> Karl,
> 
> What did you use to cut the round hole in the rear of the cabinet. I will shortly be tackling my dust collection and need to move the dust outlet port to the back of the saw. Any tips would be appreciated.
> 
> David



David, a tank or fly cutter does nicely too:






http://www.plumbworld.co.uk/hexagon-sha ... GoogleBase


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## Karl (31 Oct 2011)

No problem David. When time permits i'll probably make a proper internal chute - tapered on 3 sides towards the d/x port. The mock up i've done for now was out of necessity of getting the t/s back up and running for work purposes. 

Cheers

Karl


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## Bluekingfisher (1 Nov 2011)

Karl, As a hobbyist I have the luxury of time (it being money) Thanks again for your assistance on this matter.

I like the look of the cutter Noel has identified above, if it's not to pricey I may buy one although I don't know when I would use it again?? 

David


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