I am just finnishing building a cnc machine that i hope to cut a few boards on along with some other foam projects and i want to put a suatable dust collection system on it.
From my research it looks like there is two types high volume low presure and high presure low volume
I am allso looking for a system that will be as quiet as posable to not anoy the naybours and sutable for continuous use.
The high volume chip collectors as they are called only fillter large particals and leave the more daingerous ones still airbourn.
The high presure dust collectors catch the fine particals aswell but cant suck away such large amounst of material at one time.
With foam being relativly light and easy to clear can i use the high presure ones so that i catch evey thing and maybe use a seperate cyclone atachment to catch the bulk of the foam waste along its route?
Just my 2c, I use my vac system for shaping and sometimes for wood working. (Infrequently) Wood dust as it is cellulose has a flash point and it is a lot lower than the flash point of pu dust so that was my big concern as it is in most wood shops. That being said, from a static shock point of view, you should take an unshielded copper wire, preferably 14 -16 gauge or higher (that’s 12 guage for the non-electical educated folks) with a wrap (use electrical tape to secure) of 1 revolution per 12" of tubing. I have a direct wire for my flex hose and then wrap for all my pvc all the way to the vac system. Be sure to ground to the vac and that the vac is grounded to the electric and the electric is grounded to the true ground and you should be good to go. That’s my system, I have friends with no eyebrows from wood flash fires and I have never had a prob., just my 2c…
EPS: Blow the foam away from the bit. Sweep up after.
Urethane, XPS or other poisonous foams: suck it away.
Experienced EPS foam modellers feedback to me was that design of foam removal apparatus is not easy. Tricky for it to fit around the 3 axis spindle/router so it does not hit the sculpture/board AND has a skirt short enough that it does not get caught up in the cutter, When you cut rails you’re looking at needing 3-6" clearance suction head to cutter tip because you have to allow for the sweep up/down into nose rocker (depending on board thickness, etc.). To get a skirt 3" to 6" long you need a radius of close to 3-6" for the suction head - that starts to be a big contraption around the spindle. Of course it can be done. There are some good designs on Mechmate.com and other sites using magnets for easy removal, but mainly for cutting flat material.
Maybe I’m too casual, but simply vaccuuming the foam dust periodically during the cut works fine for the few I do a year. The router blows the chips out of its path. Since I’m watching the cut progress anyway, I do the cleanup at the same time. Works even when I cut from blocks using a 8" bit = a LOT of dust. Interesting when the cutter hits the vaccuum head!
Full face mask because EPS dust can irritate eyes and breathing lots of dust is no good. Virtually no flame risk - EPS dust is considered non-combustible.
Noise? When the cutter hits the stringer the whine will make any vaccuum noice fade into obscurity.
thanks for the replys, unfortunalty extraction is prity important as i realy need to keep the mess levels down as much as posable and i also will be recycleing the chipings and they need to be keeped relativly un contaminated. The dust shoe thing will be a bit of a issue but im wondering if i can make some sort of cyclone efect down near the router bit to help clear the dust without the need for the dust shoe to be so close to the work pice.
the reason i was thinking using a cyclone was to give me a way of taking the bulk of the wase and geting it a larger bin that doesnt fill up so quick i have still bean searching for info on the two types of vacuums avalable. the most interesting thing i found was that the best way to cut the noise was to vent the waste air to vacuum to the outside, this odvosly would not work with the large sack and filter bag type