[ihavenofish]

so, i read alot of the stuff in the eg thread and am ponder how to apply it.

i want to use it to fill the column on a bf20 (grizzly g0704) right up, with a wood plug to keep a path for the ball screw.

since this is a non structural application and only for damping and mass, im wondering if its something moderately simple to do.

basically, block off the bottom, instert the plug (2 piece with appropriate draft angles), then premix up some granite and epoxy and pour it in and pack it as tight as possible from the top.

sound right?

what type of mix is best in a filler application that wont have vibration to compact it?

also, what do you use on the plug as a release agent? just the same mould release that youd use on fibreglass moulds?

[rowbare]

Go to the dollar store and get a big candle and use that for the plug. You can melt it around the edges to ensure that it seals properly. The melting point is well above the heat that the epoxy will generate while curing. Once everything is nice and solid, break out as much wax as you can and melt the rest out with a heat gun.

As you mention the purpose is to add mass and damping therefore I don't think that the mixture is hypercritical and you probably don't need to worry all that much about the odd air bubble in the mixture and you probably won't benefit much from vibrating the mixture once it is poured into the column.

I am sure that you have read what Bob Warfield did with his RF 45 base but I am adding the link here for reference: http://www.cnccookbook.com/CCMillCNCHome.html

bob

[ihavenofish]

cool thanks. never thought of the wax plug. thats brilliant.

this machine got pushed back a little now (i had to wait til late april for it to ship, now ill probably wait til june). i got something fun to work on while i wait though

[lgalla]

The melting point of parafin is 125degreesF.Epoxy exotherm will gladly melt the candle.Use an abs pipe and don't bother with release.Leave it as part of the structure.A cast iron pipe would do better as it would add mass.
Larry

[ihavenofish]

The melting point of parafin is 125degreesF.Epoxy exotherm will gladly melt the candle.Use an abs pipe and don't bother with release.Leave it as part of the structure.A cast iron pipe would do better as it would add mass.
Larry

a tube wont work. it needs acess from the front. a tube with a plug form the front would work, but thats basically the original wood plug, which is easier for me to make.

i think you are correct on the epoxy melting the wax though. seems the epoxy hits 150C + and most common wax melts at 55-70C.

[rowbare]

Sorry about that, I was sure that the wax would survive. Thanks Larry for setting this straight before any damage was done.

bob