I’m sure someone’s covered this but I didn’t find anything. I live in Vancouver Bc. Way up here in Canada. and as you would guess, my igloo is cold this time of year.
What I’m finding is that my spoilboard tends to warp quite a lot with the temperature changes in my shop. I can’t do anything about the temp changes but I’d like to minimize the warping as much as possible. I’m using a solid sheet of 3/4” MDF screwed and double side taped down to the factory MDF base. It there a different material I could explore or would maybe cutting it int 3 equal rectangles allow for less warping? Maybe a layer between the 2 MDF pieces, like a barrier (in theory, similar to a heated tile floor) I’m just spitballing here. I’ll take any ideas you have.
Temp fluctuations day to day can be 10 degrees Celsius. I try to keep it close to even, but it’s just not economical to heat my shop all the time.
I live near Seattle Washington, the moisture keeps trying to creep into my shop. I have a wood stove that I keep cranked up three or four days a week. That being said, my spoil board warps constantly. I have needed to replace my spoil board frequently.
It has gotten to the point this winter I have to replace my spoil board once a month as I end up leveling it down to nothing.
There are options, not cost-effective. The MDF is cheap. I have a few sheets set aside in a warm area to replace my spoil board.
I used to use (thick) HDPE for my supplementary wasteboard, which is very stable across the temperature range (but of course the MDF underneath is still going to absorb/release humidity to some extent…)
Some folks have installed threaded inserts and bolts under their MDF base, primarily to compensate for potential sagging of the bed on earlier large Shapeoko models, but I guess the same approach could be used to “warp back” the wasteboard into flatness, if you have easy access to the underside of the machine. It would still mean a daily adjustment at the beginning of a shop session, which is not fun. You could also go all in and replace the MDF bed with an aluminium one (I did), but this is quite expensive, obviously.