Thread: SCMS idea, brillient or smake on the head

Tonz

The SCMS is a problem and the cutting action of the blade propels the sawdust upwards I think that is the fundamental problem and one I have been unable to solve. My saw (Bosch) would only collect about two thirds of the sawdust made and even less when the blade angled to make mitre cuts.

Regards
Paul

Probably very little effect; the cutting action of the blade is effectively going backwards and up so the chips are pulled out of the wood via the gullets and thrown into the air towards the back of the unit where what little installed dust extraction lives. It'll pick up some; but I don't think you'll see any visible improvement when in use. That's just my opinion though; maybe someone has actually tried it?

I use my chopsaw outside and aligned so the prevailing wind takes the dust away. It's a 12" DeWalt mounted on a ToughBuilt wheeled trolley so it only takes a few seconds to move it around.

I don’t like the idea of using “Wire” something else maybe, but honestly the only way I can see the “Dust” issue being resolved on what is a wonderful delightful machine too use [emoji6], is a vacuum that is strong enough too over come the velocity of dust, an working in some enclosure, unfortunately I think the solution is still buried in front of us.

Cheers Matt.
Ye I know not much help[emoji20].

As has already been said, most of the dust is directed backwards and upwards which extraction in the base wont attend to.

You have probably seen this post but maybe some newbies haven't
SCMS extraction.

At the end of that thread it shows how to direct the sawdust stream using various methods that work almost as well a a large hood and aa large DC.

Originally Posted by Tonyz

SCMS are supposed to make more dust than anything because of their design.

Which is why I regard them as open air saws, where possible, and preferably with any wind coming from behind me. Attaching a vacuum to any provided fitting on the blade guard doesn't capture enough dust to make it worth doing.

Originally Posted by Tonyz

So if the insert (where the blade cuts through) was wire mesh (instead of zero insert) and a trough/tray fitted underneath with a 100/1500 outlet at the rear how effective would it be? along with a couple of 100 bell mouths at the rear of the shroud box.

I'm guessing from this that you're not thinking of a mesh zero insert but replacing the OEM fitted inserts with something like expanded mesh with fairly large holes rather than something closer to flywire that wouldn't pass the dust very effectively. If so, why not just remove the OEM fitted insert on the saw and get the maximum opening for the saw dust? The SCMS isn't likely to be ripping very thin strips like a saw table but cross cutting, so timber would generally bridge the gap of the missing OEM insert without compromising safety.

As others have mentioned, the dust is thrown backwards and upwards rather than down, so it's difficult to see how to capture much of it from below.

Originally Posted by Tonyz

No I have not been smoling anything

"Smoling"? Are you sure you haven't?

EDIT: I use my SCMS only on site. In my shed I use a radial arm saw which similarly blows dust rearwards and a bit upwards, with the same utterly useless vacuum outlet on top of the blade guard. The RAS is against an external wall with a timber shroud behind the saw feeding dust into a 200mm exhaust fan which blows about +90% of the dust outside. It should work pretty well on an SCMS in a shed. If anyone is intersted in this setup I'll post some pictures.

Sounds like you need to blast air down from the blade guard (trying to overcome the force of the dust being thrown) into a vac pulled through the blade guide.

This of course all goes out the window as you do a shallow pass through the material.

Basically put as much of the saw as you can in a hood and draw air through it, aiming the saw chips at the BMH as much as you can.

I have a 50mm hose connected to the SCMS dust outlet and a fence at the back with a bell mouth hood attached to a 6” extractor hose poking through the fence, and it still makes some mess.