Not even finished building/testing the thing and already looking to upgrades…
Just ordered some 1/4-20 threaded inserts. I’m going to drill holes in the spoilboard for them and then cut out some cam locks. I have quite a bit of 3/4" plywood laying around after a recent project. I think I’ll cut the cam locks out of that.
The mounting holes are a standard, after that it’s the wild west.
Curious about the cam locks you’re planning. Are you talking about the hornberger style clamps.
I am interested in those as well but he uses just round holes with pegs. IMHO Perfect use for leftover tubing or old conduit from a previous build. Why the threaded inserts?
I have also bought threaded inserts for a spoil board. But now I’m rethinking that since I discovered the cam lock mechanism
Yes. I am using the hornberger style, but I threw them into f360 and filled in the holes for 1/4" hardware. My reason for using the threaded inserts is because sometimes I want to just bolt the stock direct to the spoil board. Like when I cut 1/4" plywood cutouts for my wife.
I cut the parts out tonight. Took 1 hour. Listening to the machine, I could have easily gone faster or deeper. I kept this cut with the same settings as burly. Cutting plywood, I would have had some chatter at these speeds with burly. Primo didn’t have any.
Played around with some test cuts…
7.62mm DOC at 1000 mm/min adaptive cut in pine went pretty good.
12.7mm DOC at 400 mm/min contour cut in pine went horrible. (I didn’t think this would succeed) This DOC was actually by accident. I meant to only do 7.62mm like the adaptive cut.
Finished cutting out the camlock clamps. They look pretty good.
Is that particle board your using for your spoil board? I’m not this close to finishing but was thinking of using MDF but particle board is cheaper and I will go that route if it works just as well
Use MDF…
This particle board spoilboard is the original one that I used 2 years ago when building the first MPCNC. I’ve usually needed more height and typically have another piece of MDF on top of it. I just keep shaving it down every 6 months or so 1mm at a time. It started off 3/4" and is probably around 1/2" now 
The particle board chips easy and I’ve had screws pull out. MDF also cuts cleaner.
I have two pieces of MDF that I could have used instead of this, but they were further across the shop and I was lazy.
Thanks for the insight.
So it’s better to bring the piece you will be cutting closer to the endmill rather then have the endmill drop to the piece?
Yes, that is correct.
My inserts came in. I cut a few test holes in some MDF to verify what size I need in order to screw them in. I ended up finding a 9mm hole for the insert and a 12mm reveal for the head to work the best. That gives a nice tight fit. I bought 15mm inserts, so I’ll be cutting all the way through the spoilboard in order to seat them all the way and give a 4mm deep opening above for overcuts on whatever I’m cutting.
The program is estimated to be about 1 hour to cut 49 holes. I hope to cut them in the morning.
Can you recover the inserts when it comes time to replace the spoilboard? If so I might go for the same.
They’re screwed in with a 6mm hex key. I tested one in the MDF and was able to easily remove it.
I figure for $10 it was worth a shot:
https://www.amazon.com/gp/product/B07SSCF8Y4/ref=ppx_yo_dt_b_asin_title_o07_s00?ie=UTF8&psc=1
I see one advantage being that they can be installed from the top of the spoil board. The T-Nuts have to be drilled and pounded in from the bottom, which can make it more difficult to manage.
Mostly because I hate T-nuts.
But that’s the real reason. Once I have my spoilboard faced, I really don’t want to remove it until I’m replacing it. By using the threaded inserts, I can drill all the holes after I have the spoil board flat. Then just use a T-handle hex driver to install them from the top.
My 1/4-20 hardware came in and I tested the clamps on some scrap boards. These are going to work quite well. I’ll get a picture tomorrow.
Also, the tnuts have to dig in to something. I got a whole bag for my first spoil board, and after pounding 50 of them in, they acted like little wedges and bowed the spoilboard 
I tried to have my old Burly drill out all the holes and counterbores for the new spoil board, forgetting that it wasn’t level. Had to drill out like 50-60 of the counterbores by hand because they were too shallow.
Ha,ha. Yeah, I’ve had issues with them in the past. I was originally planning on using extruded aluminum t-tracks but then I realized that would run over $100 so I change direction to go the t-nut route. Was planning on using the finished machine to drill and c’bore all of the holes and then install the nuts and flip it over and screw the spoil board down. But I like your plan better.
Do you plan on having any located outside of your working area that you’d have to drill out manually?
