Some CNC lasers and plasma cutters use zoned smoke collection system that opens different shutters depending on the gantry position. Might something similar work for holding the workpiece?
Thaddeus Waldner Newdale School Elkton, SD 57026 ________________________________ From: Roland Jollivet <roland.jolli...@gmail.com> Sent: Wednesday, June 9, 2021 10:31:01 AM To: Enhanced Machine Controller (EMC) <emc-users@lists.sourceforge.net> Subject: Re: [Emc-users] OT: About a chat here on vacuum table ideas A friend was complaining about the need for 6kW vacuum system on a large table and this got me thinking.... Another way is to divide the table up into squares, grid wise, and have a .. separate.. vacuum motor for each section. The motor is mounted under the table at the bottom of each 'box'. You can get ~1.5kW motors really cheap, and now it's easy to make up a system with as many kW as you want. Far easier to find 4 vacuum motors than a 6kW pump. Roland On Wed, 9 Jun 2021 at 17:13, Todd Zuercher <to...@pgrahamdunn.com> wrote: > For milling sheet material on a large table, an MDF spoil board on top of > a vacuum grid is usually the best option. But for small parts such as > solid wood items vacuum pods are usually a better choice. In a pod > arrangement with the part held directly is where the valves are useful. > > Todd Zuercher > P. Graham Dunn Inc. > 630 Henry Street > Dalton, Ohio 44618 > Phone: (330)828-2105ext. 2031 > > -----Original Message----- > From: Leonardo Marsaglia <ldmarsag...@gmail.com> > Sent: Tuesday, June 08, 2021 10:47 PM > To: Enhanced Machine Controller (EMC) <emc-users@lists.sourceforge.net> > Subject: Re: [Emc-users] OT: About a chat here on vacuum table ideas > > [EXTERNAL EMAIL] Be sure links are safe. > > Thank you guys for your answers! > > I've been reading and apparently MDF with a skim cut is pretty good to > distribute the vacuum all around it's surface given its porosity. I think > I'm gonna try that option first to see how severe is the vacuum loss when > the cuts are made. > > Second option would be what Todd suggests, wich is a little trickier > mostly because my surface needs to be 3000 mm x 2000 mm, so that's a lot of > springs... > > I'll keep you informed as the project progresses. > > Thanks as always for your help :) > > El lun, 7 jun 2021 a las 17:11, Todd Zuercher (<to...@pgrahamdunn.com>) > escribió: > > > It might work, but you may have trouble with the pellet sticking in > > the seat and not opening when you need it to, or worse yet if your > > part doen't quite seal good enough to the table, sucking shut and > > losing all holding power. > > > > What I've seen more commonly used is a spring loaded valve where a > > spring pushes the pellet(ball) up to seal the vacuum port. When no > > part is in place the spring pushes the ball up to seal the vacuum > > port, and the ball sticks up a bit above the part sealing surface. > > When the part is placed on top, it pushes the ball down opening the > > valve and allowing the vacuum to flow. > > > > Todd Zuercher > > P. Graham Dunn Inc. > > 630 Henry Street > > Dalton, Ohio 44618 > > Phone: (330)828-2105ext. 2031 > > > > -----Original Message----- > > From: Leonardo Marsaglia <ldmarsag...@gmail.com> > > Sent: Saturday, June 05, 2021 11:50 PM > > To: Enhanced Machine Controller (EMC) > > <emc-users@lists.sourceforge.net> > > Subject: Re: [Emc-users] OT: About a chat here on vacuum table ideas > > > > [EXTERNAL EMAIL] Be sure links are safe. > > > > I meant to say: > > > > When there is a part over that hole and before the pump is on, the > > pellet will be resting on the groove. As soon as the pump is on the > > vacuum will be immediately sealed by the part, not allowing the > > suction to suck the pellet > > > > El dom, 6 jun 2021 a las 0:48, Leonardo Marsaglia > > (<ldmarsag...@gmail.com > > >) > > escribió: > > > > > Hello guys, > > > > > > I hope you're all doing well. > > > > > > Not so long ago (or may be yes) I recall reading someone on this > > > list talking about an idea of using plastic pellets as closing > > > valves for an MDF vacuum table. > > > > > > The basic idea was: The pellet falls into a spherical hole that has > > > a round groove with a slight angle on its side. So when the vacuum > > > is not applied the plastic pellet can slide thru the groove and > > > leave the hole open (I imagine that the vacuum pump could be > > > reversed so one can blow to clear the holes and force the pellets to > the groove quicker). > > > When there is a part over that hole and before the pump is on, the > > > vacuum will be immediately sealed by the part, not allowing the > > > suction to suck the pellet. Once the hole is again free, the suction > > > will slide the pellet until the hole is sealed (useful to avoid > > > vacuum loses on the path where the tool cuts the material). > > > > > > Are there any practical examples or any real life experience of this > > idea? > > > That would be more than useful. > > > > > > Thanks as always! > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
