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View Full Version : Machine spoil board questions, your advice please



racerbear02
14-01-2015, 09:14 PM
Another newbie question, sorry :shame:

My new machine arrives at the weekend and I intend to put an MDF spoil board on the bed.

I have seem some places that just mount the board and go, while others advise a skim over with a large bit to ensure ultimate accuracy, as I am not planning initially to machine anything requiring earth shattering accuracy of depth, should I skim or not??

Thanks as always in advance.

longy
14-01-2015, 09:27 PM
One thing for sure it won't hurt to skim the spoil board then at least you know it's level. mdf is a pain for swelling just a vernier caliper along the edge and from end to it could well be 0.2mm difference so it's not goint to hurt you doing it. Video shows how to do it, if you don't already know.


https://www.youtube.com/watch?v=uRZDyDy7hKU

racerbear02
15-01-2015, 08:44 AM
Thanks longy, what he said made sense, however why did he say that he had skimmed the base and was now going to put a sheet of 12mm MDF on top? Is what he had skimmed not the spoil board? why have 2??

Boyan Silyavski
15-01-2015, 12:15 PM
Thanks longy, what he said made sense, however why did he say that he had skimmed the base and was now going to put a sheet of 12mm MDF on top? Is what he had skimmed not the spoil board? why have 2??

Cause the first one is for leveling, the second one is for spoiling for specific jobs.. He doesn't want to make holes on the first one and later change all.

EddyCurrent
16-01-2015, 10:24 PM
I think it's best to make a spoil board the same shape but slightly larger than your work piece. That way, if you have a nice aluminium T slot bed, you can prevent the tool cutting into it and still allow clamping of both the work piece and spoil board with clamps in the T slots. If you use a big sheet of MDF say, you have lost the ability to use clamps on your work piece. Obviously sometimes that's okay if you screw the piece down or use double sided sticky tape.

cropwell
16-01-2015, 11:49 PM
http://www.mycncuk.com/attachment.php?attachmentid=14444&stc=1http://www.mycncuk.com/attachment.php?attachmentid=14445&stc=1I made a board of 18mm MDF and drilled a matrix of 8mm holes in it. The back was recessed so that M6 T-nuts (the 4 pronged furniture fixing type) could be inserted. So I could clamp down to a skimmed board (I used nylon screws so I wouldn't f**k up so many cutters) The board was fixed to the T slot plate with T-nuts at the corners.

EddyCurrent
17-01-2015, 10:30 AM
Yes, it's a good idea and one I intend to make but it's back to the same problem, I would not want my cutter to dig into that either :highly_amused:
Using cams for side clamping works well with that type of board, I've attached some dxf files I did for such cams.