Miling machine gears noise.

alien97pl · Jul 4, 2021

I have a problem with gears connecting gearbox with horizontal spindle.Noise reason is too big clearance between gears (spindle-wide gear).As You can see on the photo I put on feeler gauge between gears ,and there is 0,45mm.One way to fix that I'm gonna to try is to make the wide gear shaft eccentricity to reduce gear clearance,but there is one more gear under wide gear.It may transfer noise to lower gear connection.

About gear wear.Longest gear is not used on the ends because of machine construction,and this is strange because clearance is same at the ends and in the middle(gears not worn).
Do You have any ideas how to fix that noise?
When I bought this mill ,it was working quietly because of heavy black oil or grease.After cleaning and assembly it happens.

EmGo · Jul 4, 2021

alien97pl said:
Do You have any ideas how to fix that noise?

New parts or thick grease. Sometimes that heavy open chain lube can help. Backlash has nothing to do with noise (unless you mean rattle.) The shape of the teeth is either wrong from the beginning or worn out.

cyanidekid · Jul 4, 2021

the old trick I've always herd for gear noise, particularly when reselling an old car, is sawdust in the differential

since it doesn't seem to be wear, without moving the shafts closer, thicker oil, possibly with additives such as molybdenum disulfide (perhaps that was what made the original oil black). that or live with it.

ballen · Jul 5, 2021

This is a “Deckel style” mill, suggest you repost in the forum for Deckels, you may get some good advice. You can not use grease as a lubricant here, need Vactra 2 or similar because oil splash lubricates ways parallel to horizontal spindle axis.

One way to reduce clearance is to grind/rescrape the horizontal ram to lower it. In fact one reason that the mill was built with some clearance there was exactly to provide an allowance for wear and possible rebuilding/rescraping. But that's a lot of work, and not clear to me if it is appropriate or will even reduce the noise as desired.

Peter from Holland · Jul 5, 2021

I agree with post 2
Clearance does not affect noise beside rattle
By pushing a piece of wood against the spindle you eliminate rattle and can see if that is causing it
Question
How do you know that gear is the culprit ??
Did you check the noise with the angle head off ???
Did you take the angle head apart ?????

Peter

Mechanola · Jul 5, 2021

0,45 mm is too much. Play between cog wheels does make noise because the force transition from tooth to tooth becomes stepped where it should be as uninterrupted as possible. 0,2 mm seems to be the maximum with your mill.

New gears with correct profile are the only remedy. Else earmuffs or different work on that device at slower spindle speeds

EmGo · Jul 5, 2021

Mechanola said:
0,45 mm is too much. Play between cog wheels does make noise because the force transition from tooth to tooth becomes stepped where it should be as uninterrupted as possible.

No, no, no.

The teeth are still spaced the same. There is no "stepped force transition" ever, no one with an IQ over three would design a gearset with a contact ratio under 1, the teeth are equally spaced just as when new when they have minimal backlash.

The only difference is if the load is unsteady or reversing. Backlash is not a factor in noise unless it's uneven wear like my old power hack which wore the main drive teeth very unevenly because all the force was on the draw stroke. That clunker had a whole collection of noises !

If his load is uneven (could be, it's a mill) and it's rattling, then yes. But he didn't say that. Under steady load backlash has no effect. The contact ratio remains the same.

alien97pl · Jul 5, 2021

ThanksYou all for reply! Then,without head it works without noise-as it should.With head on noise is terrible.It's easy to find noise source by removing parts.This is sound of hitting tooths.With heavy load thats much better,but without-impossible to work with this machine.
I'v found the solution.Remove this gears and make separate drive with frequency converter.That's all I can do.

Last test I'v done was removing gib and pulling ram to make the clearance lower.That works,but to make that working as it should to be,need to make new gears what will be much more expensive than conventer.

Conventer solution will make inpossible to turn the head but I'v been never using that for any jobs so i dont care at all.

Orbital77 · Jul 6, 2021

alien97pl said:
I have a problem with gears connecting gearbox with horizontal spindle.Noise reason is too big clearance between gears (spindle-wide gear).As You can see on the photo I put on feeler gauge between gears ,and there is 0,45mm.One way to fix that I'm gonna to try is to make the wide gear shaft eccentricity to reduce gear clearance,but there is one more gear under wide gear.It may transfer noise to lower gear connection.

About gear wear.Longest gear is not used on the ends because of machine construction,and this is strange because clearance is same at the ends and in the middle(gears not worn).
Do You have any ideas how to fix that noise?
When I bought this mill ,it was working quietly because of heavy black oil or grease.After cleaning and assembly it happens.

Most common reason for noise in that region is worn/damaged bearings. Most common reason for "gear noise" is...worn/damaged bearings.

EmGo · Jul 6, 2021

Orbital77 said:
Most common reason for noise in that region is worn/damaged bearings.

But not always

The entire rhythm portion of this is a totally worn-out 11" Peerless power hack, clanks bangs rattles and all -- that thing was loud.

https://youtu.be/V8MWi1cVKbI?t=2641

Got a dogwalker credit for disturbing the peace of the neighborhood, Gary was three doors down, was fun. Horn players are from Santana, David from Jefferson Airplane did backup vocals and some keyboards, met his current wife doing this, she was backup vocals .... Frankie Valli would not recognize Swamp Girl and most likely Good Thang fits some of us now ... even has a rattlesnake or two for the Texans out there

mark in Portugal · Jul 6, 2021

My old mill is also really loud in certain speed ranges.
I had the gearbox apart before I even plugged it in, and there is no visible damage; but Peter from Holland (who works with these things a lot) warned me on this forum that there can be invisible tooth damage that will cause noise.

rklopp · Jul 6, 2021

You're probably dealing with tooth wear above and below the pitch line, such that you no longer have conjugate action. There is not much that can be done in a practical sense. My Deckel FP2NC gears howl when running forward and are very quiet running in reverse. That tells me that the reverse sides of the gear teeth are still like new and giving proper conjugate action. How does your mill sound in reverse (if you can run that model in reverse)?

EmGo · Jul 6, 2021

mark in Portugal said:
... there can be invisible tooth damage that will cause noise.

There's different kinds of noise ... Red Ring used to make a sound tester that had adjustable center distances and you could put a load on the driven gear, then there was a cover that dropped down with a horn that concentrated the sound for listening ... the manual for that tester had a lot of info on the causes for different types of noise.

A possibly project for David M in Jawjhuh would be a microphone on the horn connected to a computer that would digitize the sound then graphically relate that to rpm and potential problems/causes. Kind of like modern submarine sonar

These guys bought the Red Ring stuff, might still have old publications available ?

Gear Hones, Gear Honing Tools, Gear Hobs, Hobbing Machines, Red Ring Gear Hones, Nachi Machining Technology

They had a looseleaf binder type book, something like "Modern Methods of Gear Manufacture" that was super. First section was the clearest explanation of terms and equations I've seen anywhere, then a section on their machines, then a really interesting section of examples from the Real World™. Possibly they still have those .... if not, worth hunting up an old copy. Super good stuff.

Peter from Holland · Jul 7, 2021

alien97pl said:
ThanksYou all for reply! Then,without head it works without noise-as it should.With head on noise is terrible.It's easy to find noise source by removing parts.This is sound of hitting tooths.With heavy load thats much better,but without-impossible to work with this machine.
I'v found the solution.Remove this gears and make separate drive with frequency converter.That's all I can do.

Last test I'v done was removing gib and pulling ram to make the clearance lower.That works,but to make that working as it should to be,need to make new gears what will be much more expensive than conventer.

Conventer solution will make inpossible to turn the head but I'v been never using that for any jobs so i dont care at all.

You should take off only the angle head Not the complete head The part with the bevel gears So these 2 gears you think are to blame are still in mesh
Those bevel gears tend to be noisy Esspecialy if they were taken apart and did not check their proper fit at assembly It involves bleuing one gear and see how it transfer to the other

Peter

Jonathan Smith · Jul 8, 2021

I have a FP1. The same 2 gears between the vertical head attachment and base machine make noise. The bearings are not worn. The correct ATF oil is used. The noise, call it a rattle, varies depending on load. They are straight cut gears so bound to make some noise. But .45mm (.018") is excessive. I need to check clearance in mine.

You might try borrowing someone's other attachment and checking clearance. If there was a slotter head available, it is likely very lightly used and the clearance difference would indicate proper new clearance.

I don't see a way to adjust the gap. New gears are probably the only practical way to fix it. At .45mm, the machine is probably on borrowed time anyway and damaging upstream drive components. The problem should be fixed.

The 2 gears involved are not that large and probably not very precision. They may be a standard pitch, PA and tooth count. They may be less expensive than the direct drive and vfd. Yours and mine noisy gears may be common problem and someone has a solution. That guy in Holland may know something.

Thanks for your quality question, pictures and drawing. Let us know what you find out.

EmGo · Jul 8, 2021

You guys with your fixation on backlash, you're crazy

That's all there is to it. Except in very specific circmstances, backlash doesn't hurt anything.

Search

Largest Manufacturing Technology Community on the Web

Search

Miling machine gears noise.

alien97pl

Plastic

Attachments

EmGo

Diamond

cyanidekid

Titanium

ballen

Diamond

Peter from Holland

Diamond

Mechanola

Stainless

EmGo

Diamond

alien97pl

Plastic

Orbital77

Cast Iron

EmGo

Diamond

mark in Portugal

Aluminum

rklopp

Diamond

EmGo

Diamond

Peter from Holland

Diamond

Jonathan Smith

Plastic

EmGo

Diamond

Similar threads