Gear help needed

So I made the gear. Don't get it,don't understand it and don't know what to do. I now have a 57 tooth gear. The gears mesh on the table.
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But the overlap by about 2mm on the lathe. The 95 tooth gear OD must be 194mm,and it is,but it is like something is still too big.
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The center distance is set,you can't change it. It according to calculations it must be 152mm,and it measures 150, so there lies the 2mm I am talking about. So now the only thing I can do in my opinion is to make afset pin so I can adjust the big gear.
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I guess about 2mm offset would be fine or what do you guys think I must do with this whole situation?
 

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Your numbers are right for module 2. I don't know if we discussed this before, but there is such a thing as "profile shifting", which results in smaller or larger gears for the same module and tooth count but with longer or squatter teeth. Either that's the case or the machine was manufactured incorrectly with the centre distances being off. I'd try turnin down the gear a couple of mm and re-cutting your 57 undersize. It won't be correct, but it's a small difference. I cut a 41 tooth M1.5 gear on a blank meant for 39 teeth because i fluffed up my differential indexing (forgot an idler gear) and it works just fine.
 
Your numbers are right for module 2. I don't know if we discussed this before, but there is such a thing as "profile shifting", which results in smaller or larger gears for the same module and tooth count but with longer or squatter teeth. Either that's the case or the machine was manufactured incorrectly with the centre distances being off. I'd try turnin down the gear a couple of mm and re-cutting your 57 undersize. It won't be correct, but it's a small difference. I cut a 41 tooth M1.5 gear on a blank meant for 39 teeth because i fluffed up my differential indexing (forgot an idler gear) and it works just fine.
So what you are saying is basically turn the OD down from 118 to say 116 to gain the 2mm needed and re-cut the teeth? I was also thinking of maybe making an offset bush wich slips onto the pinion pin that I can fasten with a setscrew to the pin and then make a slightly larger bush for the gear. Could that work?
 
The gear sure looks great!

It is frustrating that after all your work it doesn't fit right.

I agree that your blank diameters look good, for module 2:
the 95 tooth gear the OD should be 194mm and it is!
the 57 tooth gear the OD should be 118mm and it is!
Also, the centre-to-centre distance should be 152mm, just as you say.
(I used: https://www.mechanicdrive.com/spur-gear-calculation)

I would double check:
1) the gear cutter (usually a set of 8 cutters to cover the range of small gears up to a rack; was the proper cutter used for the both gears?)
2) the tooth depth the gears were cut to; maybe the teeth are a little too shallow?

As you already proposed, maybe you can come up with some alternate arrangement for mounting them (offset axle, additional banjo, ....)

This is a head-scratcher!

-brino
 
Yeah, you got it. It's not correct, but it would work alright.

The offset bush is probably a better idea if it's practical and doesn't mess up the mesh with something else. Keep us posted! Brino is right, it's certainly a head scratcher.
 
The gear sure looks great!

It is frustrating that after all your work it doesn't fit right.

I agree that your blank diameters look good, for module 2:
the 95 tooth gear the OD should be 194mm and it is!
the 57 tooth gear the OD should be 118mm and it is!
Also, the centre-to-centre distance should be 152mm, just as you say.
(I used: https://www.mechanicdrive.com/spur-gear-calculation)

I would double check:
1) the gear cutter (usually a set of 8 cutters to cover the range of small gears up to a rack; was the proper cutter used for the both gears?)
2) the tooth depth the gears were cut to; maybe the teeth are a little too shallow?

As you already proposed, maybe you can come up with some alternate arrangement for mounting them (offset axle, additional banjo, ....)

This is a head-scratcher!

-brino
I went through your checklist a few times before starting to make the gear and everything was fine. I have a couple of jobs to do this morning and then I will take a run at making the offset bush. I think that would be the easiest and quickest. If that doesn't work,well then I will go with making the 57 tooth gear smaller.
 
Yeah, you got it. It's not correct, but it would work alright.

The offset bush is probably a better idea if it's practical and doesn't mess up the mesh with something else. Keep us posted! Brino is right, it's certainly a head scratcher.
It really is a head scratcher,but will keep you posted.
 
So what I did in the end was the following. I made the ID of the gear larger from 28mm to 35mm because I had to go bigger on the sentrifugale bush's OD therefore I had to go bigger on the gear bushing.
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My first attempt was a failure bcause I made the offset to small at 2mm,I had to go a little over 4mm offset total for it to work. You can see the difference in the pic below.
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I drilled a small hole on the side of the centrifugal bush that went over the pin just to have something to use to move the gear into place. There is a set screw on the bush to fix it into place.
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And FINALLY they mesh.
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And here is what the fuss was all about. I only made these change gears just to be able to make greas grooves on backhoe bushing,wich I do a lot. I am now able to make the grooves at 1/2" TPI when I use my imperial setting and that is perfect for the grooves needed. The bush is about 2" long so the groove makes a full rotation.
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I just have one issue and that is that the gears are very clunky and noisy. The higher the spindle speed the noisier it becomes. I don't know why because the gears now mesh perfectly. But it doesn't really bother me because I really only going to use these gears for the grooves at the lowest spindle speed and then it is quiet. I don't really see me using the other pitches on that table,never have before.

Lo-fi and Brino thanks for assisting me with this,you two guys really helped me think here. If I left someone out......I am sorry.

Thanks for viewing.
Michael
 
Nice one!! That's what we're collectively here for :)

The mesh looks a little on the tight side, which might explain the noise. A little backlash is always good.
 
Nice one!! That's what we're collectively here for :)

The mesh looks a little on the tight side, which might explain the noise. A little backlash is always good.
On the pic it looks tight,but believe me there is enough backlash, I tried it tight and loose,but there is still this clunky noise of gears.
 
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