help with miter gear replacement

I need some help figuring out what to get or where to send a gear to have it measured so i can find a replacement or have it fixed. I have already contacted the manufacturer and they wanted an arm and leg for a gear, over $2000 for both witch seems out of line. The smaller gear is still in good shape still so i would like to just have the other one fixed if that is a possibility. That way thing still line up. I know nothing about gears so im hoping to get some help from the guys around here. I can bore the hole and drill the taper pin but have no clue about gears other than that. Here is what i can tell you about the gear.

larger gear (need fixed/replaced)
33 tooth
1" center hole
2.030 tall


small gear
29 tooth
1" center hole
1.413 tall

To what sort of machine is this going to? How important is the gear ratio? And to what is the accuracy of position important? The 29:33 ratio seams somewhat arbitrary yet may be absolutely essential.

Is this simply for power transition like an auto feed or to a precises element of a machines movement or rotation.

To me the cheapest/easiest/fool proof/long term option would be to find a pair of similar sized off the shelf gears. McMaster-Carr find a pare that has a shorter mount length then machine out the boors or add bushings as needed.

Someone with more experience then me will follow up with saying that you can braze on new stock then file the gear teeth to fit, I have done this with simple spur gears and it was a fair bit of a deal I wouldn't recommend for the first timer.

mcmaster.com/#standard-gears/=16wwxuv
less then 100$ for the pair

climb-101 said:

I need some help figuring out what to get or where to send a gear to have it measured so i can find a replacement or have it fixed.

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You could try looking for a stock gear that is close enough to modify.

Browning and Boston Gear are the two biggest, I think Linn Gear in Washington or Oregon also has stock bevel gears. Unfortunately, catalog bevels are usually limited to 1:1 or 1:2 or 1:3 and such. Bevels aren't like spurs, they have to match each other. It's the angle thing.

It is pretty expensive to make a single bevel, the braze-and-file idea is probaly your best bet if there's nothing you can modify from a catalog. MAYBE you could find a wreck on fleabay to strip but I wouldn't hold my breath. Worth a look tho.

it is for the power down feed on a 30" cleerman drill press. i was initially just going to buy a set of gears and make them fit but i'm assuming the ratio is important since the drill press has a taping feature and i think that you use the power feed on that. It also has a trip switch you can set so it will tap hole to a certain depth then auto reverse and back it self out. if the ratio changed then i am assuming the feed rate will be off for doing this. That's part of the reason i am hoping there is a way to fix the factory gear but i'm sure that's not something that is normally done.

i can still use the drill as normal and feed by hand without any issue i think but it would be nice to use the tapping feature very now and then. I had asked the company about how the tapping setup works and they had no idea to what it was even though it is clearly a factory setup and factory cast parts on the drill.


440/220 10hp 3phase
9'tall
2000lbs
30" table on it.

Nice drill. Usually those aren't worth much money because they look "old" but they drill great.

I am sorry to say I think you will find that brazing up the teeth and hand filing them is the best answer to your problem. And then watch fleabay like a hawk, you never know what will turn up.

Unless there's additional gear elements that are adjusted for each thread pitch, I doubt the small difference in ratio from 1:1 will matter for the tapping feature. Use commercial miter gears of similar size, you can try a set and if there's an issue remove them.

I'd be tempted to look for gears with hardened teeth to improve the capacity. Make sure to get the mesh correct, this will influence wear life.

Without additional gears like Milland said or leadscrews for every pitch this tapping feature is just a reverse switch you set to depth
The powerfeed is seperate from the tapping feature
I would buy the biggest set of 1:1 ratio gears that will fit the space

Peter

i will get a pic but there is different speeds you select for each thread pitch. there is a switch that it trips so you can set the depth and it will back it self out

Give these guys a call: Ask for Tom.. Tell Him Rich from Midwestern Machinery gave you his info. They used to cut gears for me on repair jobs.
Twin City Gear Co | Blaine, MN 55449 | DexKnows.com

Richard King said:

Give these guys a call: Ask for Tom.. Tell Him Rich from Midwestern Machinery gave you his info. They used to cut gears for me on repair jobs.
Twin City Gear Co | Blaine, MN 55449 | DexKnows.com

Click to expand...

thanks Richard, I will give them a call and see what they have to say.

Here are a pic of the feeds/speeds chart. After looking at them closer I dont think the "feeds" are really setup for taping, I think they are just for drilling. I did some looking in a manual i found for a smachine that was close to what mine is but dosnt have the taping setup. They say that the ":peeds" chart is to keep the drill speed at 80ft/min. the "feeds" chart is for setting the feed and they recommend .005"-.007" for drill up to 1/2", .007-.015" for 1/2"-1" and .015"-.020" for 1" and larger drills.

im assuming that by changing gears to some that are they same tooth count that it will slow the feed rate down just a little since the ratio now is 1.137:1 vs a 1:1 if i get matching gears.