So I am making good progress on upgrading my 500m X carve with an aluminum t slot bed. Hopefully this might help anyone considering using the same extrusions.
I used two of the Misumi 250mm extrusions cut at the supplier to 500mm lengths. They came with a slight warp to them, but that seems to go away when they are bolted down to a 20x20 extrusion.
@JohnScherer recommended drilling through the Misumi extrusion to bolt it to the 20x20, but unfortunately, my mini milling, drilling, lathe setup was not up to the task of drilling something that big. So I drilled the 20x20 extrusions instead. I drilled a 7/32" hole through the 20x20 at positions along the length that matched the position of the small slots in the back of the Misumi extrusion (35mm, 215mm, 285mm and 465mm). Then I used a 10mm endmill to clear out enough space in the slot for the bolt head. I used a center punch and center drill to start the hole to try and ensure good placement, that might have been overkill.
The t-slots in the back and side of the Misumi extrusion are the same as in the 20x20 and makerslide. So I got some t-slot nuts and 20mm M5 bolts and placed the nuts in the Misumi slots, and bolted the extrusions down.
I haven’t tried putting it on the machine yet. My biggest concern is the clearance for the V-Wheels. The Misumi extrusion is 15mm thick, and the stock wasteboard is 12.65mm. Plus the extrusions go all the way to the side. Going by my tests, I have about 1mm of clearance between the bottom of the v-wheels and the top of the bed. If that doesn’t work, I can take advantage of the fact that the Misumi has the same slot on the side that the 20x20 does, and just bolt the end plates to that. That would also give me an extra 20mm of Z room if I want to use a vice or something.
Also, even though the 20x20s have removed the warp from the ends of the extrusions, there is still a little sag in the center where it is unsupported. So I think I might also add a third 20x20 to the middle.
Let me know if anyone has any suggestions, or questions. Also, be sure to check out John’s original thread in for sale. He might still have a pair of these for sale.
Anyway, this is what it looks like
From the bottom
and here is the drilled 20x20