I am working on building an LR4 from my primo. I am confused on setting the rail and belts. On the side without the rail, the end stop lines up with the screw on the y-belt holder, but on the rail side the screw is about 10mm too low. What am I doing wrong?
Nevermind, I just realized the rail wasn’t snapped in to the clips.
4 Likes
This LR4 thing is great. Compared to the primo, the build went really easy. I also got a bit lucky in that it was square without any adjustments except I moved a z endstop ~1mm. XY was within 1mm to the best of my measuring ability.
The main reasons I upgraded were:
- larger size
- dust collection
- ability to use table when not using CNC in small shop
This has met all of my goals so far. Here is my first almost successful cut. I messed up grouping the tool paths and tried to go back and cut the center out with only tabs holding it together and it lifted up. Note there are not chips or dust. Amazing!
7 Likes
I am having some vibration in the +Y. It does not seem to be affecting the cutting, but it definitely is different in this direction. Here is a video:
Is this normal. This is cutting mahogany at 6mm DOC and 1000mm/min with a 2-flute 1/4 end mill.
Is the core tight on the x rail? How tight/loose are your y belts? That actually sounded pretty good to me though. I’m curious what the others have to say.
Go faster and less deep, also it sounds like the endmill might be really dull. 
The bit sounded like this out of the package. It is a Whiteside, so should be good.
I thought the general advice was to go deeper, not faster. What are typical DOC and speeds for LR4? On my Primo, I was running at 800mm/min, 4mm DOC.
Good idea. I can’t feel any movement, but I have not retightened anything after I built it, so it may have loosened up some.
I go 2400mm/min with 4.5mm DOC and 24k RPM with a 2-flute 6mm endmill. DOC has a way higher impact on the load than speed.
1 Like