Excessive machining noises during cutting
Excessive machining noises during cutting
(OP)
I am machining parts on a MAZAK horizontal two pallet, six station table and is experiencing menacing machining noises during the cutting operation. The tool is a ganged cutter of five slot cutters assembled to produce a 0.060"W x 0.380"D.O.C. on five 0.242" thickness bars at a time. Are there any suggestions to reduce this noise. Speeds and feeds are limited options for a resolution.





RE: Excessive machining noises during cutting
Resonance in the tool holder? Cutouts or inserts to change the frequncy?
TiCN cuts up to 15% quieter than WC. Try straight TiCN cermet or coated WC.
RE: Excessive machining noises during cutting
RE: Excessive machining noises during cutting
Are you truly getting a benefit from running five parts simultaneously or are you experiencing too many problems with chatter to make it worthwhile?
More info please!!!
RE: Excessive machining noises during cutting
There are a dozen different things that could be causing your problem.
RE: Excessive machining noises during cutting
RE: Excessive machining noises during cutting
Even if the cutter is made from a material that will take that speed without burning up, understand that the most common cause of noisy cuts in rigid setups, assuming the cutter is ground correctly, is excessive speed.
RE: Excessive machining noises during cutting
Saying that the cutter is a 3" solid carbide. The carbides characteristics is one of a tough, wear resistance without the super hardness (avoid chipping) type grade. I have played with relief angles, rake, fullradius nose or half radius you name it. I have settled out at 275 minutes per set of cutters which is up from 115 minutes since I started with the age old project almost a year now. I will welcome any unorthodox recommended treatment, provided of course tested before.
RE: Excessive machining noises during cutting
To me, 275 minutes of actual cutting time is pretty darn good. Noisy cuts usually result in shortened tool life.
Normally, I would expect excessive noise in a cut to be reflected in the machined surface finish (chatter, etc.). Is the finish acceptable? Are machined surfaces consistently in tolerance dimensionally?
Is the noise such that it's an environmental hazard, or just something that doesn't "sound right".
If an environmental hazard, you have a problem that needs to be fixed.
If just a strange noise, but the tool is not breaking, the finish is okay, and dimensional tolerances are being held, maybe the problem isn't so bad.
As a last (I promise) suggestion - have you considered putting the operation onto a conventional horizontal milling machine, where the arbor could be supported at both ends? It would be much more rigid that way. With some thought, I'll bet you could match the productivity of the HMC without wearing earmuffs.
Good luck.
Mike
RE: Excessive machining noises during cutting
The problem with this is it will not take into account some stiffness problems in the machine or part being machined.
Are you seeing fretting on the 50 taper? Are the parts generating some of the noise? The material you are cutting tends to vibrate more than others so much of the noise could be from the cutters strumming the parts after cutting. To reduce this you may need to add additional side clearance to the cutters, or change clamping to control part vibration.
RE: Excessive machining noises during cutting
Make the cutter OD larger with larger hardened spacers and a custom arbor with an eye to improving the stiffness of the cutter stack. A means of controlling tension in the stack may be of help also.
.0023 IPT for what is essentially a slitting saw sounds like a lot of feed, IMO.
Make sure the teeth are staggered from one cutter to the next. Don't have a tooth entering the cut at the same time on all cutters. Vary the number of teeth from one cutter to the next to try to avoid resonance.
RE: Excessive machining noises during cutting
RE: Excessive machining noises during cutting
Sorry I can’t be more help.
You might try Dave Vale at Kennametal. Dave Vale - 724 539 6807 He is an expert on cermets.
RE: Excessive machining noises during cutting
RE: Excessive machining noises during cutting
Sorry. I wrote, "custom arbor with an eye to improving the stiffness of the cutter stack". Perhaps a better way of stating the same thing would have been, "custom arbor with the intent of inproving the stiffness of the cutter stack". Forget the "eye" thing. It was just a sort of figure of speech.
Your description makes it obvious that you need to stay with your basic tooling sizes. Perhaps a custom arbor with the arbor made out of carbide or a heavy metal and brazed into the appropriate taper shank. You would need to make a tie bolt or stud that would extend through a clearance hole in the carbide arbor and would anchor its threaded end in the alloy steel taper shank. Hardened and ground spacers of the largest possible OD used with this type of arbor would make this setup as stiff as I know how.
Have you considered reworking the toolholder/arbor so that it contacts the flange face as well as the taper? I have seen this system advertised, but have no personal experience with it. Maybe other forum members could comment?
Good luck.
RE: Excessive machining noises during cutting
I realise the machine will make machining noises but the inherent sounds, as I will note it since I cannot pin point its origin at this time, is a sqeeling sound fine and high enough to summon all dogs across the nation. Keep em' comming please, these input are much appreciated. Sacrificing tool wear for speeds to minimize these annoying noises seem to be the best effort at this time and will be monitoring its effect on tool wear (tooling costs)
RE: Excessive machining noises during cutting
Is the squeal consistant for as long as the cutter is making chips? Does the sound change depending on what part of your fixturing you are working?
RE: Excessive machining noises during cutting
I have found that cutters with asymmetrical teeth produce much less pronounced vibration.
After your outermost cutter place a steel ring mounted on rubber. I use one about 1" thick and 2" in diameter mounted to an upper control bushing off an import truck. Helped a lot.
Good luck