I’d imagine its not a big deal since they are glued and nailed but I see your point.
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Likely so, I was just saying it wasn’t ideal. As I stated in my post, it’s a good compromise for the simplicity. You likely wont get any penetration of the glue into the wood fibers so you’re relying on the strength of the primer to hold the part on and in this application it’s likely sufficient. Additionally you also have the nails.
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MDF is not all that great to glue in the first place. It can really drink it up. Other material could surely hold better, this is just a case of inexpensive and easy. Adding two more under table 2x4’s (+ $10) nearly takes aways the need for the box in the first place.
The point of this is to end up with a functional CNC machine that is very accurate for the least amount of money, easily sourced, and least specialized tools. Not necessarily the minimal viable product or the best possible product. The same design ethos as the MPCNC.
If for some reason you find this method not to be up to your needs You will have a fully functional CNC to very very easily make a fantastic Table or entire shed if needed.
On that same note I am always trying to keep the target person in the front of my mind, for simplicity’s sake let’s just call them a 12-year-old that can not use power tools when their parents are not home. Limited budget, enjoys making something that stuns the parents. BUT…just like the pinewood derby in boy scouts, sometimes the parents like to get involved and have a larger budget and more tools. I do not want to force any designs to limit what is possible. The thing about his approach is I want to spend all my time helping the limited resources person, I don’t really care to spend much time debating about what makes a 1% increase with the person that has more resources. Honestly, they are less grateful. Instead of saying things like “Dude, Bro, Check this out, I made a CNC machine!!!”, They say things like “I can not seem to get this thing to cut past 28.7mm/s your design could use 7% more infill right here”.
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Neat full sheet build, am increasingly liking the outrigger designs the community are building.
Personally would have appreciated seeing something like this and the 1/4 sheet sized table in the docs when first getting started with my LR3. LR4 docs look good to me…
For my damp hot-cold cycling unconditioned space in the PNW, I would probably seal interior MDF and exterior https://chatgpt.com/share/6793d8d4-9cec-800b-957b-e5244d4d15ed
I Sprayed the whole thing with spray paint, that should seal it enough.
The smaller version doesn’t need the outriggers. The next CAD is for anything 4’x8’ footprint and smaller, those are obviously simple. Then both the the CNC interlocking versions. All will be added to the docs. Unfortunately it is just super slow progress for some reason, maybe I bought decaff by mistake?
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Praying rarely helps. 
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Do you have an update on centering, counter boring, and surfacing yet? I’m comfortable doing it myself but an official guide would be good so we have a “known good” approach.
Also curious if you can show how you mounted the saw horses to the box, or are they actually just sitting on top without fasteners or another attachment method?
Not yet. I got sidetracked by a huge project. That is mostly out of the way now so I should be back on it soon.
Just sitting on top.
hmmmmm…
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Perhaps there could be some measurements in metric? I guess I could convert between inch and cm but…
I’m having trouble locating a sheet of particle board. Does anyone have any suggestions for a waste board? Thanks
Mdf, particle board, plywood, anything relatively flat.
The earth?
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Stawp!
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Compared to a basketball it is RELATIVELY flat…
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Dork’s
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I bought all the materials for this today, with a few minor substitutions: 7/16" OSB and 1/2" MDF sheets. Also the only MDF strips I could find were 1/2" thick. Shrinkflation ¯\_(ツ)_/¯
Got a decent deal buying most of the primed MDF as a 10-pack of 8’ boards for $55 CAD. Had to buy the 9’ segments by the linear foot @ $1.38 per - they were available in 16’ segments here (BC) next to a little DIY cutting station with a mitre guide and some hand saws.
Total cost was a smidge over $200 CAD ($150 USD?) including the 2x4s for the sawhorses. Will pick up two pairs of sawhorse brackets tomorrow from a local shop for another $22. All well under budget.
Thanks for the plans! I think I have everything to start my LR4 assembly now 
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What if I need to splice the y-rails? Where do I put the slice?
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Wherever you want, really. Personally I’d do it somewhere in ‘free space’ between the support ribs as a plain butt joint and then back it with another single piece under the joint. For the bearing side I’d fill the joint and then very lightly sand it back to flush/smooth, taking down as little as possible.
You could always push the joint as far out to the ‘far end’ of the table as possible. Most people I know who made full-size machines do something like 90% of their cutting in one half of the table and probably 75% in the close corner.
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I love to hear that!!!
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