Thread: SCMS dust extraction

Hi Mick:

Fantastic to have the photos, thank you. I can't believe you made all that for less than a hundred. Particularly like the drawers. Well done!

My setup will be different as my scms is going to be built into a side bench. That said, your mobile unit would be very handy to push away when not using and pull out when needed.

Originally Posted by QC Inspector

I think if you were to put a curved piece of sheet goods that matched the arc the back of the saw creates when swung from one side to the other, it would cut out the dead air space in the corners and help a little with the air flow.

Pete

Agreed Pete, I've got some 3mm mdf which would curve around beautifully, although it will need to be well supported as it is pretty flimsy. Still thinking!

Bob, many thanks for your input, I value your comments with regard to dust extraction. The blue pipe was that length only at the start, it was a discarded 8m length of swimming pool hose that has been put to various uses. Prior to building the mobile dust hood for the SCMS I did in fact have a vacuum hooked up running via the Oneida cyclone, worked quite well but nothing like I hoped it would work.

Testing with and without anything on the back of the SCMS showed up some peculiar dust patterns. Without any kind of vacuum attached, but a short length of hose to the back of the SCMS, 400mm in fact, and pointing downwards, I was left with a line of dust on the ground directly below the travel of the hose, plus the other dust everywhere situation. Without anything attached, I just had dust everywhere and also in places I wouldn't have thought possible.

The final finish was to have the blue hose attached to the end of the bracket at the end of the tube sliders and pointing southward, effectively dropping dust into the collector from about 280mm above the horizon. This works very well in certain situations where having no hose attached doesn't work too well at all. The pictures show the original length of blue hose, it has been surgically shortened and attached and now works very well.

Having no hose attached, but using the dust hood I've built, dust collection doesn't work too well when cutting a 45º cut with a 45º bevel and withdrawing to near the 340mm cut start as the overhead dust opening is a bit out of the main suction area. By adding that 400mm of hose and pointing it downwards from the end of the sliding tubes and using either gravity or the suction of the hood system, I have a much better dust collection.

I do know the limitations of a 4" system, I'm actually running a smaller system, 100mm and that's the OD not the ID

Phil (QC Inspector) that is a good idea for myself as well, I'll await the next neighbour to dispose of some 3mm ply, then attempt to fabricate some curves.

Lucky Duck, The drawer handles literally turned up on a nature strip during the build of the unit. As the drawers were the last thing to be built, it worked out beautifully, except I only scored 6 handles but I have 8 drawers; I'm still looking and as I have a ute with a tray back, it's amazing what one can come across that others have no hope of scoring.

The drawers are made from stuff scored from an office desk, a bedside table and an Ikea wardrobe, with the handles being from a custom build, lounge corner piece setting

Mick.

Thanks for explaining the situation with the hose. This is useful to me because lots of people ask me about SCMS extraction and not having one myself I can only draw on limited testing experience.
Cheers
Nbob.

Bob, attached are a couple of pictures of the "bobbed" hose.

One is taken with the saw sitting upright, the other is taken with the saw in the down ready to cut position, both with full, "towards the operator" positioning. When the cutting starts, the rails progressively slide towards the back of the dust shroud. When finally against the back wall, the hose emits a stream of dust for a couple of seconds after the cut is finished, which just drops straight into the big gulp quite effectively.

Mick.

IMG_8309_SCMS_10.jpgIMG_8310_SCMS_11.jpg

Originally Posted by Optimark

Bob, many thanks for your input, I value your comments with regard to dust extraction. The blue pipe was that length only at the start, it was a discarded 8m length of swimming pool hose that has been put to various uses. Prior to building the mobile dust hood for the SCMS I did in fact have a vacuum hooked up running via the Oneida cyclone, worked quite well but nothing like I hoped it would work.

Testing with and without anything on the back of the SCMS showed up some peculiar dust patterns. Without any kind of vacuum attached, but a short length of hose to the back of the SCMS, 400mm in fact, and pointing downwards, I was left with a line of dust on the ground directly below the travel of the hose, plus the other dust everywhere situation. Without anything attached, I just had dust everywhere and also in places I wouldn't have thought possible.

The final finish was to have the blue hose attached to the end of the bracket at the end of the tube sliders and pointing southward, effectively dropping dust into the collector from about 280mm above the horizon. This works very well in certain situations where having no hose attached doesn't work too well at all. The pictures show the original length of blue hose, it has been surgically shortened and attached and now works very well.

Having no hose attached, but using the dust hood I've built, dust collection doesn't work too well when cutting a 45º cut with a 45º bevel and withdrawing to near the 340mm cut start as the overhead dust opening is a bit out of the main suction area. By adding that 400mm of hose and pointing it downwards from the end of the sliding tubes and using either gravity or the suction of the hood system, I have a much better dust collection.

Like you, I value Bob's comments. I'll be very interested to hear what he has to say about this. I have thought about keeping the vacuum cleaner on my SCMS, even with the big dusty and shroud, but considering what I've read about vacuum cleaners (even the "good" ones), I haven't been game to suggest it, not without external venting!

Originally Posted by Optimark

Lucky Duck, The drawer handles literally turned up on a nature strip during the build of the unit. As the drawers were the last thing to be built, it worked out beautifully, except I only scored 6 handles but I have 8 drawers; I'm still looking and as I have a ute with a tray back, it's amazing what one can come across that others have no hope of scoring.

The drawers are made from stuff scored from an office desk, a bedside table and an Ikea wardrobe, with the handles being from a custom build, lounge corner piece setting

Mick.

Jolly good show. It's funny what a good feeling it is to get/make something valuable and pay little or nothing for it. I remember being a child watching my Dad save every last couple of screws/nails/washers/bolts, and I always thought it was a waste of time, and why doesn't he just buy new ones when needed? -- after all they don't cost much. "Funny" in the sense that now I love pulling out my cans of the same and finding just the right bolt or washer and essentially getting it for "free".

Originally Posted by LuckyDuck

. . . . . It's funny what a good feeling it is to get/make something valuable and pay little or nothing for it. I remember being a child watching my Dad save every last couple of screws/nails/washers/bolts, and I always thought it was a waste of time, and why doesn't he just buy new ones when needed? -- after all they don't cost much. "Funny" in the sense that now I love pulling out my cans of the same and finding just the right bolt or washer and essentially getting it for "free".

Yep - good feeling.