UK Primo Router build

Doesn’t look like there are too many UK Primos in build so I thought I would add mine in.

I have been following Ryan and this site since around March/April, decided it would make a good lockdown project. In the end I delayed until Primo was released and I was back at work anyway.
Did most of the printing back in July time when the F variant was released, then got delayed by other projects until around a month ago when I finally got a suitable table.

The work space is 450mm x 450mm with an 81mm Z axis. I do plan to try to mill aluminium with it one day so I tried to keep the size down. I ordered most things from Ebay/Amazon locally and ordered the Rambo board from Ryan. Total cost of the project materials has been a few quid under £400.

It all went together pretty easily. The guide is really good! I did manage to mangle a belt tensioner, then ruin the top corner getting that part out. Hence the odd grey parts in the build.
The core was a bit wobbly, then I read about the F Variant cores that had the error in originally. So I printed off the modified core clamps to correct. If that doesn’t work out I’ll just reprint the updated core.

I decided to switch to dual end stops last week, got it all wired up today and did some test movements. All works!
The plan now is to mount the Rambo on the wood plank overhanging the table, then neatly run the wires up. The first task will be some pen plotting, I need to test some changes to a gearbox adaptor plate design. Plotting the outlines on some A2 card and cutting it out will save me having to wait for the laser cutters to reopen. Figured that would be an ideal first test.

Then I’ll attach the router and every present I ever give from now on will be an engraving… Or a large drawing.

!

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You should just try aluminium, was less of a problem than I thought. I did four crowns, some cuts in wood and then made a touchplate out of aluminium with a 55x75cm Primo. Worked like a charm.

I’ll be a little less cautious then. Just need to order some bits for the makita router now.

I finished wiring up the end stops today and ran a simple drawing with a pen. Barring a small Z height issue smooshing a pen up it went well. I’ll try it again tomorrow with a less destroyed pen and see if I can get a useable outline from it.

Wire management will be an ongoing project. For now it’s functional for the most part.

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I will be interested to know what bits you use and where you get them from in the UK. I am just printing the J variant as we speak as I have some 1inch OD stainless coming. Got 6m so will be building the max size I can with that, probably 750mm wide. I will post pictures once I am in the build process.

I drew a picture! There is still a pretty big wobble on the core, but it was good enough to pen plot. The pen plots looked good, so next I want to rout the plates out of plywood to double check the dimensions are correct. Should also be a good next step for the setup.

I can’t get anymore prusament PLA to print the updated core for the moment. So I am going to try Technology Outlet’s professional PLA. I’ll give that a go over the weekend if it turns up on time. Hopefully then I can try the router.

In terms of bits, I was going to get some 1/4inch shank straight router bits from toolstation to start with. Then probably engraving bits from Ebay.

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Well Technology Outlets professional PLA was a joke. Spent half an afternoon playing with settings and my extruder, only to have it jam within 10 mins of a print starting. So I’ll have to wait for Prusa to figure out how to make Prusa branded customs forms before I can get some more filament for the core. Should only be a couple of weeks though.

Got bored of waiting for Prusa. Ordered some PETG and printed it again with 70% infill.

Replaced the old core with this and used the updated core clamps. Still had the same wobble as before. Not sure if this was because I used PETG, or something was off in the print. But I tried the modified core clamps out of desperation and they actually worked! It’s nice and solid now so I got to trying my first piece.

Well it moved all find until it actually started cutting when it just stopped moving. After careful examination I noticed that it was moving, just very very slowly… The job time in repetier host was 60 hours, so I think I must have had the wrong units somewhere for feed speed in Estlcam.
Annoyingly I didn’t save the DXF file to the cloud and it was left on my home computer, so I couldn’t redo the job at the unit.

But still, here is the very first thing I routed! Managed to to one layer and start the second before I got bored. The depth of cut was set to 1mm, figured I would start lightly and move up from there.

In the gcode, feedrates should be mm/min and distances should be mm. Estlcam can support different units in the gui, but make sure the gcode units are right.

That was the problem, Estlcam was setup for mm/s. Which explains the issue perfectly. Thanks for the pointer, made finding the problem very easy.

Feed speeds are sorted. Got some routing done today, messed around a little bit with spindle speeds, feed rates etc.

Then noticed there is some pretty big slop on the z axis bearings. I don’t think thing I had this on the first core that I printed, so maybe this is the result of PETG not being quite so accurate. The linked video is the slop that I get on the z axis, this is with the bearings adjusted towards the conduit as far in as they will go.
Next week I will double check if I get the same issue with the first core/

https://youtu.be/o8eK4Dc9SdM

Just a quick update on the z axis slop. I noticed tonight the z axis clamps were also updated in August along with the core. So I am printing out some new z axis clamps and I’ll see if those make a difference next week.

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