I am using a Gen 2 Redline Foreman and getting a unique problem I never had with my X50 woodworker. I face with a 1/4” tool since ATC is not available yet, and I used to do the same with the X50.
Settings are scaled way back so feed is slow and speed is high. Tram is excellent, bolts are tight. Using the heavy QCW. Pushing and pulling on the spindle (redline) gives about 0.020” flex front to back and maybe 0.005” side to side. Reset acceleration to be very slow after initially making things very fast.
Toolpath was generated on fusion 360 using pocket toolpath, not facing because the shape is not that simple so I don’t want to waste time facing scrap.
Example image below. What else should I try? Again, this toolpath used to work, it would required sanding as the tram wasn’t as good and it would leave faint burns at the spots where it paused, but it was acceptable to just remove with a quick belt sanding. This is much deeper.
yea it’s intended to be flat and it starts from a fairly flat piece. It’s maybe a 2mm step down which has typically worked, but some of the pieces on this board also have a .2mm finishing step down. I also ran (on a piece not pictured) this surfacing path twice, the second one with Z being 0.5mm lower. It is somewhat better but still way too rough for what it normally is.
This shouldn’t matter, but when I fixed the tram yesterday I used .010” shim stock behind the Z sliders bottom bolts. These bolts are tight but I wondered if there could be flexibility from introducing a subtle gap between the bearing block and Z slider mounting plate? Not enough to gouge like this though
Another note, My spindle is mounted with the clamp about half way down, maybe I can move the clamp closer to the collet end but I’ll have to remove, and retram the Z slider. I played with spindle mounting on previous machine and didn’t notice these kinds of effects.
What kind of 1/4 bit are you using? If its one of those straight fluted ones with the carbide brazed on I could see this happening because most of the time those dont have a flat face. The carbide cutting edges stick down further than the center of the bit creating a swirling pattern.
This is the same 1/4” spiral down cut carbide bit I always use. I think it’s SpeTool or something cheap but it’s the same bit I’ve been using for years with good results. Equally good to something like Bits and Bits, except longevity. The bit style hasn’t changed just the machine has.
I’ve run 3 or 4 of these so far to test and they all behave like this. I’ve probably made a hundred using this method on the first machine. Dropping feed to 10% reduces the effect but it’s still there. I will attempt a true facing tool path in one direction only and see if the direction change is giving me issues.
For what it’s worth, I had a Y-axis repeatability problem when I installed an Elite/Masso upgrade on my BB Foreman. After considerable frustration, I tracked the problem to the “factory-installed” shaft coupler on one of the new Y-axis motors. The set screw that clamps the coupler to the motor shaft wasn’t tightened well, and the coupler could slip on the shaft by a partial turn, but not a full one. After I tightened it properly, the repeatability problem was gone. So I’d suggest checking out all the Z-axis mechanical connections on your upgraded machine.
I appreciate the last 3 suggestions and will check them out on Monday when I’m back at the machine and follow up. I was able to get a better finish with a single direction facing toolpath on the x axis, but still rough. I will check all connections and I have just cleaned the collets. Thanks gang, happy Easter if you’re celebrating
I’ve considered it, and I don’t know how to rule it out. I’m using the heavy QCW and it is well secured to the table using the provided screws. I read some movement when pushing on the table with a deflection gauge mounted but nothing crazy. I am going to run again using the smarter path @TMToronto mentioned with a .5mm finishing stepdown.
I just ran this tool path with no luck. It seems the direction change cuts deeper than .5mm. I could make the finishing step smaller but I think this will result in a continuously shrinking step down to remove this. I feel this somehow must be a hardware issue. I will reach out to @OnefinityCNC support and let everyone know what I find. Open to more suggestions here.
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