Do I upgrade to a Primo? Want to get faster at surfacing. Should I leave well enough alone?

Heyyyyy Everybody it’s been quite a while.

I built my burly mpcnc a few years ago with the 3/4 piping with a cutting area of 2’x3’. Asides from not fully mastering speed and feeds it’s a great little machine And I put a lot of hours into it.

I haven’t had time to mess with it all summer but I’m looking at the colder months to get back into it. The machine itself works fine. I just wish I could surface uneven boards faster with it. I have a1/4 shank 1” fly cutting bit that I use but it feels like I either can’t run the steppers fast enough or slow down the spindle enough (without losing torque). It’s been a while so I can’t recall the exact IPM on the surfacing moves but I’ll update later.

I’m debating on switching to primo I was wondering is the improvement in rigidity noticeable and do you guys suggest maybe running a real spindle instead the dewalt 660?

If I’m reading this right I just need a hardware kit new belts and all new printed parts? Also is there been any noticeable upgrades to the Rambo board I believe I have a version 1.2? Maybe even firmware upgrade or something?

The one thing I wished this machine to do is be controlled by some sort of joystick or controller. But I want to say people said the marlin firmware was holding it back.

Oh yeah the main projects I want to do is if it matters is flags and also resin epoxy boards. I’ve seen people surface epoxy on the CNC but I’ve also seen them run it through a planer to shave off the top layer.

a planer will be faster if you have one big enough.

I can’t say for comparison to the Burly, but my Primo at 25" by 37" is pretty good. I really should have span supports on the Y, but I don’t, and it has been good for me.

I don’t think that there’s much if any advantage to a new RAMBo over an older one, but going to 32bit electronics was a serious boost for me.

Have you see this thread?
Joystick managed by Marlin

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So I have a pretty good dewalt planer but it doesn’t really flatten warped wood without a sled and shims. Kind a pain to be honest and only good for 12” wide boards max.

I would really need a big jointer or drum sander but no room at the moment for more toys.

The y axis reinforcement you’re talking about is that extra or part of the normal primo build?

Just curious do you happen to know what speeds you can run on it?

Mid-span supports are add-ons (not usually needed, but can be a good idea for long tube spans.) I don’t have them, and it hasn’t been a problem, but I’m also using 1" DOM steel tube. They just add some support for the tubes in the middle, so they have less tendency to sag. you can’t do that for the gantry tube though.

I have never really tuned to see how fast I can go. My default 1/8" profile in Estlcam is set up for 1800mm/min (30mm/s) and I have run it up to 150% speed, so 45mm/s at 3.25mm DOC. I’m pretty sure that I can run it faster near the corners, but really haven’t done much testing. I don’t like the idea of wasting material, so I’m pretty conservative.

I haven’t tried any significant work on aluminum either.

Now that my LowRider is finished, I’m thinking of cutting the Primo down in size to be able to work faster and on harder material.

Sounds like a problem you need to fix asap :joy:

As for speeding things up, I cannot speak for the abilities of Rambo or the Marlin firmware, but in general higher driving voltage for the stepper motors will allow higher speeds.
Keep in mind that you can’t just crank up the voltage and everything will go faster. You need to not only make sure your hardware can handle the higher voltage, but the software needs to be calibrated to go faster.
I think I’m running about 30 volts on my box right now and I’m getting decent speed. I tried a 12 volt power supply to experiment some and the motors would skip a lot of steps while attempting the same speeds.