Cnc dovetail cutters
but that even still seems too big and might contribute to increased cutting forces and the awful hammering sound. Would the chipbreaker on the insert impose a faux positive rake on the insert and reduce cutting force? On the one I made I pushed the cutting rake to about -12 deg. It seems like too much, but its a trade off of decreasing that thin section area and making the rake more positive (ie: getting the insert to sit at or behind CL instead of forward of it). of cutting rake has me worried, even for steel. of cutting rake (MSC has a pos/neg misprint I reckon) and +10 deg. After some careful measuring and confirming in MSC's big book, the insert is actually sitting so that it has -15 deg. The one I made has a slightly larger diameter neck to help it out some. I started studying the geometry of the now broken cutter body and see that the section across which it failed is pretty thin, but because the cutting diameter so small and the insert HAS to be the size it is, there's not much that can be done about that. Since the job is pressing I decided to make a new cutter body out of some tool steel. After studying the remains I think I can place the blame on cheap insert screw stripping out, insert coming loose, binding in the slot and torque took care of the rest.
Got about midway down the part and kaboom! This time the cutter body twisted off right at the corner of the insert pocket.
This time it sounded like a handful of gravel in a washing machine no matter what F/S numbers I ran. So this afternoon I tried one of the new inserts. The insert that the cutter came with had a nice chip breaker on it, however the replacement inserts I got have no chip breaker ( MSC Linky). Running flood coolant to flush the chips out as well. I am slotting most of the material out before bringing in the dovetail cutter so it only has to remove the undercut portion.
#Cnc dovetail cutters full#
Ran one part beautifully, then on the second part the insert basically exploded as soon as it started making the full width cut in a female part. It only has one insert, so it hammers like crazy and I still end up running it slow (S1500/F2.5 = 0.0017 chipload). So I gave those up and got an inserted carbide cutter.
#Cnc dovetail cutters plus#
Ran them incredibly slow and still had dulling problems plus each cutter is slightly different in size so keeping tolerance was a pain. Warping is not an issue - the parts get bandsawed into 1 inch sections after machining. I need to machine a matching set of dovetails run down the length of the parts (4 matching pairs total). Material is 1018 CRS 1" square x 18" long. I've got a job that I'm starting to wish I didn't take on in the first place.