My first build will be smaller, wondering if I can use a sled to handle larger stock

Mostly Printed CNC - MPCNC Advice
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I started this a long time ago but never finished due to moving and life stuff. I’m ready to finish it now, last night I ordered the rest of the hardware I needed from V1 store, printed out the assembly instructions and cut my conduit rails. I have all the parts printed for the older Primo MPCNC and decided on a machine footprint of 24" x 24" (for now), which I know is small, giving me a pretty small cutting area.

I want to do this as proof of concept, and getting lots of smaller drawer parts just to get going, work through lots of the old lumber and plywood stock that I have mixed in smaller cuts and just see the machine in action.

I was thinking though, with the small machine, maybe I could still work on longer boards, up to any length, but realistically only a few feet max, if I babysat the machine a little bit? I wouldn’t do this often, but I’d like to know if I at least have the option. I just started reading about the process of zeroing the bit at bottom left, 0,0 mark. Could I put a longer board, say 12" x 48" on a flat router sled, and work on 12x12 sections at a time, and maybe using a reference spot on the board to move it another 12"?

If so, this would be amazing for flattening and cutting some of the stock I have that I’d love to flatten and work on. I have some 4’ boards of cherry, oak, etc. Only about 8" wide, would love to use this as a planer, even if it takes a while and i have to babysit.

Long term, once this is built, my next project will be building a new Lowrider of a bigger size, and maybe I’ll keep the 24x24 Primo and build another Burly, or just upgrade it to Burly. I thought about printing all the parts again and just doing Burly for my first machine, but I’m thinking I already have the Primo stuff sitting in a bin, I’d like to just use it. I did buy a Jackpot CNC controller for this build instead of using the older control listed in the Primo documentation.

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Hey Mike, you don’t even need a sled, you can just plane the first part, slide it further, run the program again and plane the second part etc. It does make sense to have some kind of reference (if the boards are straight at the edge, just screw a board down on the side), but besides that it’s pretty straight forward.

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Thanks for the quick reply Philipp, good to know it’s that simple and it will work.

If I’m using the router to plane a board flat, I suppose I can reference Z depth off any section of the freshly planed surface, and keep sliding it along. That will be such a game changer for me, being able to plane all this lumber I have sitting. I’ll have to look into surfacing bits.

Another thought I have is making longer cabinet parts and drilling holes up and down the sides, like an Ikea bookshelf. Was thinking I could reference the last hole as I slide the work piece along. Keeping it all perfectly square might take some measuring but it all seems possible to me, sorry I’m totally new to CNCing and machining so this might be extremely amateur questions. I’m sure flipping and moving and reorienting workpieces is part of the process of milling especially as parts get more complex.

Super excited to get started. Unfortunately heading out of town for a few weeks for work but look forward to my build and using the machine. I bought a 24x24x36 grow tent which I’ll use for most of the cuts as a simple enclosure, of course I’ll have to not use it when I’m working with longer stock. I have a shop vac with cyclone I’ll try to hook up as dust collection, working in a basement so really trying to keep the dust to a minimum.

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I have rarely machine a piece from two sides, that does not happen too often actually. Referencing the last hole does work, but you need a guide at the side again.
And for planing: You don’t even need to set the reference point on the “new” 0, at least with my controller I just rerun the program, because it has the exact same zero like the one before.

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Makes sense, thanks very much!