What do you mean by a small radius you filed on the o flute?
The o-flute comes as a sharp corner (or square end mill). I file a very small radius instead, making it a bull nose, to come out as a shinier finish.
I also have tried the same toolpath with a brand new toolbit that has corner radius already from the factory - 2 flute up-cut end mill with corner radius of .02ā. The straight 1-flute with hand-filed radius came out cleaner.
Would you be able to elaborate more on this and/or possible show some pics? I wasnāt able to make the ball-screw itself budge when trying to move it by hand, but was able to move the coupler itself a bit by hand (with an allen key for a little more leverage). I am thinking you are on the right track of what may be going on here.
I will try this, and Iām sure it will help. Iām just kind of bummed out a little that it canāt do a nice smooth finish at 40-50% stepover like I can do at my workplace.
Sometimes those are the breaks.
Check this out
Maybe heat is the issue
https://forum.onefinitycnc.com/t/hdpe-colorcore-material-issues/4270/3?u=ken5
A few thoughts:
Do you have the z stepper with the brake? And have you done a bolt check over the full machine? Iām wondering if there is a harmonic going on as there are some artifacts on the v-bit portion. If your getting vibrations, thereās either flexibility in the system (e.g. something is loose) or something is unbalanced/bent.
The z motor coupler might be further apart than it should be, I checked mine and I donāt have any play between the two couple parts. I suspect one of the pinch bolts might be (or might have been) loose and the red part of the coupling could have some wear in it.
Does the swirl seem to be worse later in the cut? There isnāt a lot of thermal mass in a 1/8ā bit so it could heat up, or get chips stuck to it. There may also be a difference in the cooling effect of the air flow from dust collection that might impact this.
Do your chips on the OF look similar to what you get at work?
This is what I get with a 1/16ā o-flute:
Just curious if you have played with climb vs conventional cutting? I donāt think you can eliminate tool marks, but it seems like its less of a machine problem and more of a feeds, speeds and tooling issue.
Iāll stick with what I originally saidā¦end play in the ball screw. The top and bottom bearings are contained within the end caps of the slider. They are pressed from the inside and are captivated against a shoulder in the end cap. The end caps are fastened by machine screws to the slider frame. There is nothing specific that would hold the optimum length to insure that there is no end play in the ball screw. The ball screw is shouldered to go through each bearing. If the distance between the shoulders is short, that would mean that the screw itself can move up and down between the bearings. That was the problem I had. I fixed the problem by drilling and tapping the bottom of the ball screw, and adding a screw and washer to draw the screw up against the bearing.
If you donāt have the capability to drill the screw, you could add shims to take up the end play.
Your machine is plenty stiff enough, especially cutting something like color core so chatter can be ruled completely out.
Can you show us a picture of the modification you made
I think I can picture it but a visual would help
Thank you for that diagram! I had a very big issue (mm, not 0.mm) z height problems on a OpenBuilds machine due to similar issues, but a more crude setup. Tightening the couplings to the acme screw on that machine such that the couplings reduced play through tension solved most of the issue. The rest was fixed by upgrading to the 1F, and letting someone else continue the effort.
@FlytesWorkshop did you ever resolve this? Iām fighting the same issue on my machine. Did you try Derfās suggestion? Iām almost at that point.