[shimmwagen]

trying a new cutter out, walter prototyp AH3021138-3/4, 8 flute solid carbide endmill. cutting a 16" half circle/8" radius in a cast iron part, machine is a daewoo dhm500. approximately .200" of material coming off. manufacturer recomended this-----S= 4400 RPM... sfm of approx 860 based on structural steel 44W / A36 / 1015 F= 352 IPM... ----- we ran it at this and we could barely hear the cutter, nice chips coming off and the size was dead on. the strange thing is that we got feed lines on the surface, almost looked like a zip tie/zap strap! we slowed down feed into the 100's which shortened up the lines but they were still there... any one have experience with these endmills?? all the math works out for depth of cut and speed/feed. the tool rep thinks maybe the machine can't keep up with the code but i am just using a g3 to make the arc...

this is the current solid carbide code im using, i just changed speed/feed accordingly for the walter endmill...

(FINISH 7.811 RADIUS)
(HOLD SIZE TO 15.62 +.01/-0)
N3T53M6(T3-H194)(.75 FINISH ENDMILL)
T55
G54G90G94G0X-3.1Y-6.4375B0
S800M3
G43Z3.0H194
Z1.
M8
G1Z-1.1F40.
G41Y-7.4375D194
X0.F13.
G3Y7.4375J7.4375
G1X-3.1
G40Y6.4375
G0Z1.
M9
G91G28Z0.M5
G91G28X0.Y0.
M1

any thoughts/suggestions would be appreciated.

glenn

[dcoupar]

Is the tool running true? Can you post a picture of the feed lines?

[shimmwagen]

i didn't take any pictures and the tool was being held in an er40 collet, 50 taper spindle and running true to less than .001. super busy at work right now so i havent had a chance to play with feeds too much yet.

[Geof]

Yes very likely the cutter is not running true.

[Perfect Circle]

Get rid of the collet.
At those feeds and speeds the radial forces due to climb cutting are pushing the endmill away from the part.
Go with an em holder or a ISCAR MAXIN power chuck...

Product_Tooling

Good Luck!
:cheers:

[shimmwagen]

ran it again. rough at 3500rpm with 150" feed, finish at 4500rpm and 125" feed. estimate 150Ra surface finish. two .160" rough passes and one .027" finish pass. i dialed in tool and found around .002 runout with er holder. switched to solid holder and runout is now approx .001.

shaky cell phone video here...

https://www.dropbox.com/s/fk4tuocfc4...2022.13.31.mp4

[shimmwagen]

Attachment 222540Attachment 222540Attachment 222542

some pictures...

[underthetire]

Let's see the whole set up. Looks like part chatter in those pics.

Sent from my G-Tab Quantum using Tapatalk

[shimmwagen]

Attachment 222618Attachment 222622

[shimmwagen]

not the greatest pictures but i think one can figure out the plan. quite a bit of open space between bolt/clamp end and the "meat" of the part. large back face cutter does the underside of the part, and as you can see by the milling marks on the clamps and bolts we don't have much room to move clamps around.