Archive through February 23, 2000

[jimt]

Has anybody tried using slotwall (or slatwall) for a Shopbot table top? If you're not familiar with it, this is the stuff you see on the walls of retail stores that has t slots on about 4 inch centers. Seems like it might work like a table on a metal milling machine, with some t-bolts or nuts used to clamp parts all over the board. Aeem's like it might work OK, costs a bout $40 for the paint grade MDF type. What do you think?

[ddchap@ix.netcom.com]

Jim, I've thought the same thing, but don't know where to buy it or what would be the best hardware to use for hold downs. I wonder if the folks who sell slotwall sell some hardware that might be adapted as hold downs. Also, various types of hold downs that might be adapted are available through Woodcraft Supply and many other woodworking/tools suppliers.

[seaside@esva.net]

Jim,

Sounds like a great idea, especially for holding small or odd-shaped pieces. I would worry about hitting the bolts though and destroying a router bit; do you think nylon bolts and nuts would be strong enough to use for the hold-downs?

Bill

[mcw]

I have worked with a lot of Slotwall, and I dont think that the material would hold with using hold down bolts, its not that strong. On the other hand, you can get plastic or aluminum inserts that slide into the slots to reinforce them for heavier loads.

My .02 worth

Brian Miller

[rwill40158@aol.com]

I've just assembled my bot and I'm just at the point of buying a spoil board. I think the slot wall is a great idea. I will make some custom inserts to improve the strength of the slot. If worst comes to worst, I can flip it over and forget the idea (Paint grade is only $35 cdn). I was thinking also that a vacuum table could be held down in the slots and be positioned anywhere on the table. Thanks for the great idea.

[tnelson3@uswest.net]

I thought about the slotwall a bit when setting up my shopbot and decided that the material wouldn't be strong enough. I had a piece of it (mdf) laying around and looked closely at the slots and pried on it with a screwdriver.... It broke with only medium pressure on it.
What I did was to level out a piece of fir plywood (3/4) and then mill a grid of 5/8 X 12 inch slots on 4 inch by 16 inch centers (between the 2 x 4's of the sub surface) I then added a larger slot at the center (the 12 inch way) that measures about 1 1/4 by 1 3/4. This allows me to insert a standard metal working tee nut and use hold downs also from metal working... So far, it's working out quite well... I generally clamp down fixtures to make my parts.
As far as hitting the metal bolts, I just have to be aware of their locations and program around them.

[parlee@island.net]

Yet another method ...

I drilled a matrix of 1/2" holes into a sheet of MDF. I use small 1/2 wood dowels in these holes to align my work piece with the router and provide a stop for the wooden cams I use on the opposite side. The cams pivot on 1/2" hardwood dowels and are basically plywood circles with offset centers and "tails" for turning them. I have several cam sizes to adjust for different sized work pieces since my holes are spaced around 1 1/2" apart. I sometimes use spacer blocks between the cam and work piece to adjust for work piece size and/or protect softer woods from the cam.

I do a lot of surface routing and engraving with small bits and find this method holds the work firmly enough without much fuss (or worries about errant MOVE commands).