@SLCJedi I will give this a shot. Do you mean that you leave 0.005" radial stock and come back in and clean it up with one last pass? Or do you mean with a offset in the “heights” tab?
There’s an option to do a finishing pass in most toolpaths. I usually set that to 0.005".
Thank y’all for the advise and tips. I really think the finish improved a lot by leaving some stock for finishing passes.
I have a SST lube cube on order for air blast/lube. What kind of mix and ratios are you guys running in your machines? I’ve read a mix of alcohol, water, and CoolLube?
2 Likes
I know from experience that the reservoir that comes with the sst lube cube is not compatible with alcohol. He has had multiple customer’s reservoirs spontaneously shatter after prolonged exposure to isopropyl. I had to swap mine out for one made from a different material. I run straight 90% isopropyl from the bottle with it turned down enough that most of it has evaporated about a minute or so after the cut is finished.
I have been running QualiChem XTREME CUT 251C from Tormach that @Vince.Fab recommended. It doesn’t evaporate cleanly like iso alcohol will, but it has great cooling and lubrication.
1 Like
@nwallace where did you get the different reservoir from?
@SLCJedi im going to look into this. Do you think it could mix in with alcohol for less cleanup?
I’m assuming you just run a very light mist of coolant?
@Brasch i feel like I read on an old post that you run a mix of some sort?
I use Koolmist 1/8th + half alcohol and half distilled water with a SSI mister. The mix helps a lot. I’ve tried straight alcohol and it didn’t work as well
Maybe. But I’ve also seen the SST canisters crack under pressure with alcohol. I imagine any alcohol increases that risk. There’s also the possibility that the alcohol will counter the oil in the coolant.
Yes, I do a light mist most of the time. I’ve rarely done a heavy mist of I was really pushing in a long job.
1 Like
I bought a generic one on amazon. They are just filter housings.
Thanks guys! When my lube cube comes in I will see mix up something. Ive got a 2.2kw spindle on order cause the Makita is not doing the trick.
Side note: How are you combating all of the chips on your ball screws? I can’t imagine running the machine with the ball screws covered in oil and aluminum shavings is going to bode well over time.
@Brasch I ordered some Koolmist what is the 1/8 you referenced? I know you said 1/2 alcohol and 1/2 water. Is it denatured alcohol?
@nwallace do you know if denatured alcohol has the same effect on the canister?
The 1/8 is the koolmist, I’ve been running this mixture in the same canister for about three years and haven’t had an issue but I hadn’t heard about them exploding like someone said. So we’re going to check it out this week when we’re in the shop see if we should replace it.
So heres my experience because i got a lot of conflicting info from people.
Arcs and circles thst are not splines will ignore any of the tolerance or smoothing settings in the tooltmpath config. There simply arent points used between xy movements. You can verify this 2 ways. 1. Look at the tool path data and show points. 2. Export a circular toolpath and compare the gcode with tolerance set to .1 no smoothing and .0001 with. The gcode is the same because the machine determines the resolution for arcs in the controller.
In the post processor there are settings for minimum and maximum (im mm) arcs and circle diameters. One of these is “built in tolerance” this does NOT affect arcs and circles unless its outside of those mins and maxes. Its defaulted to .002 now i did set mine to .001 but it doesnt really matter
You can use MDI to look at the default value for the shapeoko its $12 id imsgine theyre the same but on the 5 its defaults to .002. I noticed it only displays 3 decimal places in the log console but it did accept .0004 as a value and i did hear an audible change in movement after this but no visual chsnge in my surface finish for arcs though so i set it to .001 for now.
I THINK a lot of this has to do with the vibrations from using this style of a stepper driver. Its not the snoothest and you can feel the vibrations induced if you just touch the spindle as its making an arc.
Doc for finishing, spring passes, travel cut speeds none of those really made a difference in any of my testing ive done.
I did turna cceleration way down partly for finish and partly becsuse the 80mm spindle is pretty heavy and it was actually violent when it changed directions. Im cirrently at 50% and its pretty happy. I may even go lower when doing aluminum work tbh. Im not in it to save 5min im in it to make a processional looking part.
Misting made no difference other than making the ridges in the finish more shiny.
Maybe this helps some of you out.
Set arc resolution lower in the grbl settings
Slow the finishing/spring passes way down
Set acceleration to 200 or 250
Remove vacuum attachments for finishing passes (any extra weight on the spindle)
Odd number flute finishing mills with a shallow helix
5 Likes
I use Cool lube 2210AL in their jr mql and even after 200+ parts I haven’t had to refill the small res yet. It does leave a film on the part but comes right off with 70% iso and the finish is great but it was not cheap.
1 Like
Denatured alcohol would probably have the same effect. You would also need to better manage the fumes with denatured. There are ingredients in it that are much more toxic than isopropyl (which isn’t good for you either) when inhaled.
1 Like
@BlueMeanieTsi this is great information and sounds like you spent quite some time trying to chase down the root cause. Are you using Carbide Motion? How did you adjust these settings?
You can change acceleration and toleance through MDI in CM.
$120-122 is acceleration xyz
$12 is the tolerance for arcs.
Im still not getting what i want out if it surface finish wise on arcs but its the best i think im going to get. I still suspect the jerky stepper drivers are to blame here though. Higher end machines have much smoother stepper drivers
Thank you! I will try these settings and see if it helps. The arcs I can understand. Hopefully the acceleration lowering will help with some of the heeling marks on direction changes.
This topic was automatically closed after 30 days. New replies are no longer allowed.