Have the MPCNC built and have completed the test cuts in foam etc. I did not build a spoilboard initially, so working on that now but having issue trying to determine the best way to go about it. My workspace area is 24x24. My thought was to cut a 24 wide by 35 piece of MDF to slide in and out, but the toolhead is not the same distance on each side from the edge for cutting purposes (X coord and the sides that would be stationary and where the feet attach). I may be overthinking this, but just trying to determine the proper specs and repeatable process.
Could you show us a picture of your machine, please?
I had my Primo on strips of wood and then slid a spoilboard between them. Don’t make it bigger than your cutting area, otherwise you will have a hole when you plane it again and can’t put larger workpieces on it.
I’ve reworked my machine twice. My final design has the spoilboard sized and positioned to the working area of my machine and floats on the base board. For me, what was important is that the router bit can reach every corner of the spoilboard.
At some point, you are likely going to want to surface your spoilboard so that it is milled parallel to the working plane of your machine. If the spoilboard is bigger than your working area, then surfacing the spoilboard will leave a pit. This pit will make it difficult to work with oversized stock.
If the spoilboard is “floating,” then you will either have to put the feet of your machine up on blocks, or make your legs a bit longer (the thickness of your spoilboard), or give up a bit of your Z working height.
Note there are lots of spoilboard designs for various hold-down solutions. My recommendation is to ignore the designs in the beginning. Just use a piece of MDF with screws or double-sided tape for hold downs. Use your machine for 100+ hours. By then, you will have a much better idea of which (if any) hold-down solution(s) will work well for your kinds of projects. Then you can toss your “trainer” spoilboard and build something with more features. Note that most of these hold-down solutions use the CNC to create the features, so you will also have developed the skills to make your new spoilboard.
Re: hold downs. I’ve used home made double sided tape a billion times, works really well and doesn’t cost much. I have t track on my table, looks cool. I quit using it once I bought a pin nailer. That thing is awesome. I carried the t track over when I remade my machine. Because it still looks cool :laugh:
I did strips of MDF between t tracks, took the measurement between the shoes, and fit in as many 6" strips, 4" strips would have been better. One thing I did not account for was since I made my rig minimum z giving up 3/4" to a spoil board is a significant loss of Z. So at some point I expect to double the base under the feet so I can have a waste board and full Z travel.
Home made as in two pieces of blue tape with CA glue between? I’ve seen people do this in videos. I assume it’s a lot cheaper than the more expensive (and thicker) double sided tape? I want to give it a shot.
I just use a battery powered brad nailer. Spoilboard is going to get spoiled anyway, easiest to pry up what’s left and hand-sand any little burrs left where the nail went in.
That’s good to know, thanks. Does your nailer put a pin through 3/4” MDF, Baltic Birch or a similarly thick hardwood? I’ve never owned one, I assumed they were for very thin stock