OK some laziness is kicking in I have a primo that in theory can be used to cut my strut plates, but it is out of level (I somehow managed to knock it out 1.5mm from xmin to xmax. I could relevel it easy enough but it’s days away from being disassembled to make way from the LR4. So I am bouncing alternatives around. the simplest (and I have seen examples) would be just to rip strips that fit into the space in the print, foregoing the wings. Assuming the front plate and the bottom plate are the same width I could just double stick tape the two together and layout and drill the bolt holes in both plates ensuring accuracy. I can fretsaw the cutouts on the xmax side easy enough.
If the wings are more that just gap filler, I could go this way. Rip the two strips to full width and layout the notches and holes manually and just drill and cut to the lines. If I wanted to get fancy I could design and print a layout and drill jig combo.
The front strut and bottom strut are different widths just so you know. I cut my strut plates with the temp 3D printed strut plates on the LR4 and it worked great. The fit amazed me! Some pretty smart guys designing all of this and very helpful people on this forum.
I cut my LR3 plates on the Primo and my LR4 plates on the LR3, both of them having a smaller footprint than required by flipping the cut over. I have a video on how to do it on my channel, that might help.
Only on Z? Just cut too deep and it will cut a few mm into your spoil board, but still make good plates. If you XY isn’t square, that sould be a problem. But otherwise, should be fine.
This might be blasphemy but this may be one of those spots where CNC’ing something is slower than just doing it manually(if you have existing manual tools). I look at those parts and say 30-60 min to cut them out. Now I do need to learn how to split jobs so in this instance that is part of my calculations. So for this I am looking at learning how to split a job and then a failed run or two so 4 hours at least.
I’ll be trying the manual way tonight if it blows up in my face I’ll let you know
Just something to think about. The LR4 instructions say you can cut the struts with the temporary 3D printed strut plates installed. That’s what I did and they came out perfect. If I recall correctly it only took ten minutes to cut both struts. Hopefully this helps .
I definitely appreciate that. But I think the crucial dimensions are the bolt hole locations. I may be wrong. But cutting the perimeter would be easy on a tuned table saw. But you need a square resulting truss. CNC is the right tool for that, IMHO. But you can do it however you like.
This is the simplest way, but the bolt hole locations are a critical element for the machine by locating the braces on the gantry properly.
If you’re really excellent with layout and fabrication by hand, this is doable (I’m not, i tried this approach on my first beta build, it wasn’t good.)
For my 2nd beta build, I 3D printed some temp plates in sections, which is so stout that this gantry is still assembled (I also built later beta builds, so eventually I’ll rebuild this one).
So, as it turns out, I had used my 1/4 hardboard for something else (it sucks getting old and the memory goes). Unfortunately, I was stuck at home, and I could not get more, so I thought I would spend the evening figuring out how to split a job.
After a couple of hours, I am stuck on how to split the job. Obviously, it has to be more than splitting the SVG file in half that the strut generator produces.
Add two reference pin holes to the svg and export it
In Estlcam rotate the drawing to the correct orientation
Set the left reference hole to zero
Delete the sections of the drawings that hang off the front. Then use engrave instead of part.
Set up the job and remember to put in holding tabs and set the depth for the two reference holes to cut deeper into your spoil board. (it’s a good idea to do some test cuts to make sure your dowels fit)
Save job as struts_step1.gcode
Back to step 4 but this time flip along the horizontal and don’t cut the reference holes save as step2.gcode
Run step1
flip the board use the reference holes and dowels to align it
run step2
In my experience find out they don’t fit and spend a bunch of time debugging speeds and feeds only to realize your bit is just dull so put a new bit in and do it again.
Oh thanks,
I added holes at the centerline in fusion. Should they be to one side of center instead?
Step 5 is the issue. is that an estlcam function or the external DFX editor (I just downloaded LiberCad. And apparently clicking on a line segment and deleting is not a thing (looking for ungroup)
If they’re on the center line they should be fine as long as they are symmetric around the flip axis. The way I did it and is shown in the video the holes are on the flip axis so you put the same hole on the same spot on the spoil board. If they’re somewhere else and are symmetric around the flip axis you can align one hole on the workpiece with the other hole on the spoil board etc.
