Thread: Is on top or bottom best "dust extraction"

Originally Posted by Timmy

I am very interested on what people are doing in dust extraction...no, not advice on model.

Timmy

Hi Timmy,

I've been persevering with DC on my 12" Contractor's saw for a while, but am still getting, not so much chips, as very fine dust to the fron of the machine (most which seems to land on me), plus some behind and around the saw.

I have a 2hp DC, collecting from the bottom of the saw.

During the week, I've had delivered a SUVA TS overhead dust collection contraption, so this coming weekend I'll be hooking that up to an overhead suction channel (some PVC pipe & some flexible 100mm hose). I'll be posting results and, maybe, a few piccies.

Cheers!

Originally Posted by Timmy

Been talking to some of the guys on another thread (Gumby, Silent C) and I am very interested on what people are doing in dust extraction...no, not advice on model.

I have the TSC 10hb and been spending the day experimenting on blocking all the gaps underneath the table. Initially tried with unit as manufactured than began by stuffing plastic bags in all gaps to stop airflow and big fridge magnets (thanks Silent C) around the gaps of the two large winders. I tried a Z24 rip blade and a Z80 fine blade and also raised it to max and min height. Using a 2hp new dust extractor.

Results...still getting fine chips infront of saw and on floor. Using other saws in the past I found little if any dust or small chips. Additionally, I had mentioned the effects of using the zero clearance inserts to effects on dust extraction.


Cheers
Timmy

Timmy use an 80Z blade as the gaps of the teeth on the 24Z blade are toooo big and allow the dust to escape!
:eek:

You need to unblock some of the gaps under the table top as airflow is necessary to carry the sawdust away.
Most of the dust goes under the top. A small amount can get caught in the blade gullets and comes up past the top. This is the dust you are encountering. Finer tooth blades have a lower tendency to do this as the gullet is much smaller. But the blade size should suit according to the job in hand. e.g. 80T for fine work & crosscutting and 24T or less for ripsawing.

The solution is a major dust port below the bench top. (say 3 to 4")
And a secondary dust port say 1 1/2" fitted to the top of the saw guard. If your saw guard doesnt lend itself to fitting a dust port make a new guard that can be dust ported.

You WILL get dust above the table, some operations a lot more than others.
It not just carry round dust that comes out the top but also rear blade re-entry dust too.
Also if you are trimming or jointing less than the width of the blade you will get plenty of balistic dust over the front of the table.
The amout of dust sent where also depends on the amount of blade penetration ant the type of material.
I've had a number of benches & had extraction with differing sucess.
The current machine with suva guard and 2 by 3" ports works well if you can keep the guard clearances down.

As said before don't bung up all your air flow under the bench.
I leave the front ( smylie )slot open, the air enters there & crosses infront of the blade on its way to the outlet.

Use as little flexible pipe as you can. some while ago now I replaced most of the flex with straight pvc 100mm on my machine with dramatic improvement.

The battle with dust is never won.

cheers

Thanks guys for the very helpful replies!!! Given current thoughts, my first step is to build a perspex extractor housing "on top". Thinking that I will need to replace the one currently on the TSC10HB. Looked at the suva guard, but really trying to keep some bills in the bank for some scrapers.

Anyone got photos of the set ups they arte currently using. Soundmans correct...this dust is a continual problem.

My original idea for this post was to identify the best way in actually getting that stinking dust into the pipes. ie. thoughts on 75% volume from top and 25% from underneath, top unit no great than 30mm to aid in extraction velocity etc. etc. etc. Once we have identified the best process then we can connect our dust extraction units/cyclones/PVC pipe (and the 25 threads associated with this). I know it sounds a little techo, but given some of the lateral thinkers on this site, than we could come up with some good reference material or sites in the future. I understand the great web site that the cyclone templates are sourced are great too, but just talking about the actual point of extraction of the table/saw.
Cheers
Timmy
PS How do you put one of those smiley faces on your reply?

Just forget the smiley face. Looks like I sorted that! Take me annother month to work out how to put two in!!!!!

Don't get over excited about asigning proportions of air flow, the limit will be how effective you can make your plumbing.
I had quite good extraction on a previous bench using my then 1hp extractor from below and a shop vac hooked up to the standard guard.
If you get a 32mm hole saw and carefully bore a hole in the top of the guard (it will just fit) & glue in a short piece of 32mm electrical conduit.
that will provide a good vac connection. this will require high preasure vacume to get a result.
cheers

Originally Posted by Timmy

Thanks guys for the very helpful replies!!! Given current thoughts, my first step is to build a perspex extractor housing "on top". Thinking that I will need to replace the one currently on the TSC10HB. Looked at the suva guard, but really trying to keep some bills in the bank for some scrapers.

Anyone got photos of the set ups they arte currently using. Soundmans correct...this dust is a continual problem.

My original idea for this post was to identify the best way in actually getting that stinking dust into the pipes. ie. thoughts on 75% volume from top and 25% from underneath, top unit no great than 30mm to aid in extraction velocity etc. etc. etc. Once we have identified the best process then we can connect our dust extraction units/cyclones/PVC pipe (and the 25 threads associated with this). I know it sounds a little techo, but given some of the lateral thinkers on this site, than we could come up with some good reference material or sites in the future. I understand the great web site that the cyclone templates are sourced are great too, but just talking about the actual point of extraction of the table/saw.
Cheers
Timmy
PS How do you put one of those smiley faces on your reply?

Timmy, I have a TC-12 (10HB on 'roids) and am getting similar issues with dust collection. Although i have a 2HP dust collector and an overhead Suva guard, I still get a fair amount of dust thrown at me in about the 6 o'clock position.

A few faults I have yet to deal with:

- the 3" outlet in the Suva guard is slightly aft of the back of the blade; I need to insert another outlet towards the front of the guard.

- the velocity of the air needs to increase, I think I can improve this by using 75mm and 100mm poly pipe (as suggested by others).

- finally, I am thinking of installing a shroud inside the saw to "swirl" the dust toward the 100mm outlet at the base. I may even install another 100mm outlet at the base.

If anyone else has proven ideas, I'd like to hear them!

Dust collecting sucks...

G'day Groggy,

I've spent a large portion of this morning setting up a SUVA dust collection system on my MJ-2331 (Timbecon branded) 12" contractor's saw, using an overhead post method.

Given the height of the standard splitter assembly, the dust collector hood is still proud of the table by around 30MM.

I think that I'm going to have to find some acrylic or such to bond to the dust collector hood to bring the edges close(r) to the table; ditto the rear of the collector.

In short, it works, but would (I think) work better if I managed to clse the gap to the table.

I'll also say that the assembly instructions left much to be desired, and even more to the imagination

Anyway, some pics!

Cheers!

Great photo's Steve. Yes I can see what Groggy says about the suva guide being aft...if in fact its the same setup as Steve's. My plan this week is to make a guard like the suva, but given what I see, I may make the guard a little narrower to try to increase the velocity of the air flow.
Will keep you posted...hopefully photo's.
Cheers
Timmy

Steve,
Part of the problem with your suva guard not reaching the table is - you need to remove the original splitter(behind the blade) and attach a different splitter to it. Delta have a snap in spreader which I think is compatable with the Tsc-10hb saw.
I have a similar suva guard and Delta snap in spreader set up on my uni-saw.
You will always have a problem with the guard if you don't change your spreader/splitters.
regards rosethorn

steve's othe option id to trim the old splitter down. Its probably that tall because it had to support the prevoius guard.
It only needs to be just a few mm shorter than the blade at its highest
You may want to make a several spliiters for times when you are doing "non-thru sawing" with the blade at lower penetrations.
getting another 3" hose into that guard will improve matters considerably patricularly if you can get some 100mm straight pipe close.
Some work on the internal aerodynamics of the guard are helpfull too.
As far as getting it close to the work, you might want to source some brush like what is used on truck & buss mudguards. I have some pieces that were given too me but they are in the too do pile.
cheers
Just had another look at that pic.
I recon you might get a 4" hose into that guard.
That would help the airflow.

Hi Steve, Looks like the sort of thing I've been thinking of. Did you buy it or is it home made?
If its bought where did you get it from?
Brushes for the bottom edge sound like a good idea thanks soundman.
I currently have the same woeful guard that comes with the TSC10hb on my saw and its not very user friendly or effective at dust collection.

Thanks In advance.

Bruce T.(kiwibrucee)

Hi Guys,

Thanks for the input

Rosethorn: yes I realise that, and am contemplating a few options. I have and as yet untried micro splitter that I acquired with a GrrRipper a short while ago, but, unless soemone can tell me otherwise, that dinky little piece of plastic just doesn't look to be up to the job, and I hate kickback

Soundman: the idea of those brushes sounds very interesting; I'll give it a whirl. Any idea where one can source that stuff?

I don't much fancy the idea of "trimming" the OEM splitter, and it probably wouldn't work anyway because of the design. However, I might try and draw up an replacement design, and see if I can get a local machine shop to fabricate a lower version. Gee, don't basic T/S (or most other machines) soon get to be a sink-hole of energy and funds, wasting time not making sawdust...Maybe the dark side is beckoning

In any case, I'll try the brushes before any more pachydermis (geddit) blocks my view

Kiwibrucee: it's a standard cattledog listing from Carba-Tec. The whole package comes with a floor-standing assy. and the alternative ceiling mount. I chose the latter as it was much easier to assemble given that my shed/garage has several lateral timber beams upon which I could easily attach a transverse beam to hang the vertical SUVA mount from.

One other thought: The SUVA widget has a counter balance, but it's too heavy, so I had to put on a counter-counter balance to, well, balance things out (that's the curious looking black thingy on the front of the collection assy.

Second other thought: The SUVA is marketed as a "premium" item, but its quality of component parts is pretty average, and the accompanying documentation is fit only for tearing into strips and hanging in the thunder box



Cheers!