Tuning CV Settings - my amateur findings - to discuss!

[AvB]

Are you MatejO on RC Groups? That's great to hear that you are doing a similar thing.

Actually I get really good results using a small flat end mill with parallel passes to do the whole chord. The moulds need very little polishing to get them mirror smooth.

Also in practice I don't have the cutter step up around the LE and onto the flange. I use sweep on the LE curve to create a small "fake" surface extending a couple of mm above the LE, and include that in the geometry for the main surface cuts - so the cutter follows up the LE perfectly and lifts up on the fake LE lip before doing a direct move to the next pass.

[rmat]

Hi AvB,

no, sorry, Im not that one, I am very unactive in rc the last couple of years.

Nice to see different aproaches to same thing. Nevertheless, try using bullnose cutter, you will get even better finish , and also more possibilities to cut some spots with different strategies.

[AvB]

That's great, thanks. When I searched on RC Groups it seemed that there are quite a few guys with the name Matej ... we don't see that name here in Australia! Cheers and all the best - I would like to see the stuff you're working on with your CNC. I posted some pics of just a few things I've done in this forum.
viewtopic.php?f=5&t=1743

[Robertspark]

Yes... But.... Uccnc don't like linear > arc / arc > arc / arc to linear moves and does not apply the same controls or limiting parameters as linear > linear motion

The new planner with s-curve acceleration will apparently improve these elements.

[jerkko]

As mentioned in previous post, UCCNC dont like linear/arc transitions....is there any workaround to improve that? I use Solidcam which produces quite lot linear-arc-linear-arc style of code (not sure why...). Each transition is like exact stop, motion is extremely jerky. My machine is highly modified chinese 6040 with hybrid steppers, capable to run 10000mm rapids and >1500mm/s/s acceralations.

Example code which run jerky regardless how I change CV settings:

N90 G1 X4.042 Y-126.187 F1156
N95 G3 X3.959 Y-126.389 I1.898 J-0.898 F1087
N100 G1 X3.927 Y-126.48
N105 G3 X3.872 Y-126.661 I1.981 J-0.697
N110 G1 X3.793 Y-126.974
N115 G3 X3.765 Y-127.101 I2.036 J-0.516
N120 G1 X3.696 Y-127.464
N125 G3 X3.683 Y-127.546 I2.064 J-0.389
N130 G1 X3.625 Y-127.939
N135 G3 X3.616 Y-128.006 I2.077 J-0.307
N140 G1 X3.569 Y-128.415
N145 G3 X3.564 Y-128.466 I2.086 J-0.239
N150 G1 X3.525 Y-128.891
N155 G3 X3.522 Y-128.925 I2.092 J-0.189
N160 G1 X3.49 Y-129.359
N165 G3 X3.488 Y-129.393 I2.094 J-0.155
N170 G1 X3.463 Y-129.836
N175 G3 X3.462 Y-129.853 I2.097 J-0.12
N180 G1 X3.44 Y-130.295
N185 G3 X3.439 Y-130.329 I2.097 J-0.103
N190 G1 X3.409 Y-131.239
N195 G3 X3.409 Y-131.256 I2.099 J-0.069
N200 G1 X3.397 Y-131.707
N205 G3 X3.397 Y-131.724 I2.099 J-0.052
N210 G1 X3.374 Y-133.111
N215 G3 X3.374 Y-133.128 I2.1 J-0.034
N220 G1 X3.359 Y-134.982
N225 G3 X3.359 Y-134.999 I2.1 J-0.017