I’m not quite sure how to approach my table top. I’m using 5/8 thick MDF. Originally, I was going to glue and screw a sheet of 5/8 MDF to the top frame of my torsion table, and then add another sheet as a spoil board on top of that. I realize height can potentially cause an issue. I already have a 5/8 MDF board attached to the bottom as a bottom “skin.”
I’m just not sure if it is wise to glue and screw a 5/8 sheet of MDF to the top and then add an additional sheet on top as a spoil board, or simply have the entire top be the spoil
board that I replace periodically.
This picture is of the torsion table with the bottom skin applied.
This image shows the sheet of MDF on the top as well as the bottom. My question is if I should permanently mount this sheet to the table, or make this sheet the spoil board.
I think you can go either way here. My table just has the top as the spoilboard. Some people will resurface it when it gets rough looking but it needs to get pretty bad before it becomes a problem. I haven’t surfaced mine at all.
As far as strength of a torsion box table goes, you just need a skin on both sides for max strength. So, if you wanted to have a replaceable spoilboard, you could permanently attach even a 1/4 inch skin and screw fast a thicker replaceable spoilboard.
Nothing wrong with putting the top and bottom skins on, then flattening the top skin with your machine, and then adding a sacrificial spoil board on top of that. The advantage of flattening the “permanent” skin before adding the “temporary” spoil board is that ideally you would not have to continually do a resurfacing whenever a new spoil board gets added. Decently flat MDF spoil board laid down on a flattened torsion box should not need a separate resurfacing until it got very scarred up from use. If the additional spoilboard sticks up above the part your machine is riding on, then just add some strips to elevate what the machine rides on. Hope this helps!
I chose to use hardboard instead of MDF for my table top “skin”, simply because my table is removeable (with wheels on one side) and I wanted it to be lighter weight. I then attach/detach the MDF spoilboard top as needed.
So far, I’ve found that screwing into MDF isn’t great. It feels that it strips easily, even with a pilot hole. Is this an error on my part or am I overthinking it? I would be concerned unscrewing/screwing back into the same holes with MDF. Is that your experience?
Yeah, MDF isn’t the greatest structurally. I use pocket hole screws specifically, so there is minimal splitting since they are “self tapping” to a degree. Pre-drilling would be a good option too just to prevent splitting. The MDF top is so heavy that just 4 screws in the corners hasn’t been an issue, it’s mostly to keep it from shifting/ rotating, not to “hold it down.” I’ve only screwed it in and unscrewed it a couple times, but I could always countersink a few new mounting holes if I needed to (deep enough so I wouldn’t hit them with the bit if digging into the spoilboard.)
I used glue and a million brad nails to attach my hardboard skins to the MDF. And glue and brad nails to build the MDF box as well.
Ah man, I can definitely see those brad nails being better than #8 screws. Whomp. I believe I’ll purchase some of the pocket hole screws to try as well. I’ve never used those before.
Another nice thing about pocket hole screws, in general, is the smooth shank (only half threaded) so they’ll pull boards together in a clamping fashion. Great for holding stuff down to the spoilboard. I like square head drive too.
