I have been playing around with dust collection and after many attempts, I have found nothing really works better than what Mark designed. I did drill a couple of extra holes in the attachment directly below the vacuum hole nozzle and that seemed to make the most improvement.
The problem I am running into is static build-up from the depron when it is cut, making the foam dust collect on the rollers and the foam board. I found that even holding the vacuum nozzle right up to the cutting bit makes no difference.
Cutting wood, a majority of the dust gets sucked up by the vacuum. Here at work, down in the shop they crap-can the dust nozzle attachments on the spindles and just take a vac nozzle and suck up the dust when it builds up on the table.

 

take some fine metal chain and make it so it barely touches the media you are cutting, then run the other end of the chain to a known good ground, some metal ribbon would also work

 

The dryer sheet is a very good idea.

But here is a solution you might want to consider to get rid of static charge buildup.
With the system shown below, as the pressure rollers come in contact with a static
charged material, it will dissipate the charge safely to ground.



Make a wavy grounding clip out of KS brass 3/8"w x 1/32"thk.
Solder a wire to the brass clip.
Mount the clip to the pressure roller lift cam with 2 #6 x 1/4" long sheet metal screws.
Run a wire to the 24 VDC grounding lug of your power supply.
Be sure the wire is long enough so when the pressure rollers
are in the up position there is about 1" of slack.
You can take a nail and lightly tap a small dimple in to the grounding clip where
it contacts the center of the pressure roller end. put a little light grease on the dimple.
Make sure that the clip just touches the roller. You don't need any pressure on the
roller end to do the job.

Make sure that you use safe wiring practices.
Make sure the new ground wire will not interfere with
the safe operation of your pp.

Hope this helps.
George

 

I will probably have to make a ground clip and wipe the material down. Last night I was cutting some 3/4" foam, which is the worse for static after the its been milled on for a while. As soon as I touched the board, all the static transfered to me along will all the foam filings.
I think the static is being built up by the flex shaft.

 

Foam has enough dry air pockets in it to become statically charged just by the bit rubbing against it.
If you have a low humidity work shop environment, It's almost impossible to avoid. :girl_cray2:

I worked as a design engineer in the 80's for a business products company.
I designed cutting and welding dies for all kinds of foam and vinyl products.
The antistatic measures taken in that place were unreal.
Static electricity and concentrated vinyl fumes do not mix well.
One nasty spark in a stock room and GAME OVER. :nervous:

Nuff said.
GHB :byei:

 

I wonder if running a ground wire dragging on the foam, connected to the power supply ground would work?

 

I tried the wire on foam thing. It works, but tended to get in the way.
That's why I made a clip.

GHB :02cents:

 

I've been considering wrapping a coil of bare copper solid wire around the rollers on the drive end of the unit and running it back to ground on the power supply.

 

5hp shop vac and a 120 psi air gun is what I have resorted to.

 

Back in the day at Navistar, the techs in the pattern shop rigged up compressed air lines to the 5-axis router whenever they cut Renboard parts. It was a kind of kludged together mess, but it blew the majority of the chips off the model toward the back where they had a plywood "fence" around the router that gathered the chips for eventually vacuuming.

Renboard is polyurethane, so it also had its fair share of static issues, but the compressed air overcame that. Of course, we're talking an industrial environment where gigantic compressors make all the air in the world available for something like this but...

::shrug::