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My Rostock MAX didn't have any 4-40 x 3/4 cap screws included, and 4-40 x 3/4 flathead screws were apparently supplied instead. The problem is they aren't long enough to reach the t-nuts if I use washers under the heads, and it just doesn't seem like a good idea to use flathead screws with no washers unless I countersink the holes in the heated bed PC board, because I expect the board would crack instead of compressing like the wood/melamine panels do.

It looks like the board is designed to allow a countersink, but I wanted to be sure this is safe to do before I chance destroying the board. I do have a proper countersink bit and a well-controlled drill to let me do this carefully.

Opinions? Am I going to run into the same dilemma installing the RAMBo?

- dan

for the ONYX I countersunk and had "just enough" length to reach the t-nuts. I still need to remove the PS for one of the screws.

I decided I didn't want to countersink the PC board holes, and instead went out and got some 4-40 x 3/4 pan head screws for both the heated bed and the RAMBo. They fit fine, and I'm not as likely to torque them too tight.

- dan