How close should machined gears mesh? Need advice.

[sixdogs]

I bought a PTO powered slit seeder and in looking it over have figured I might need to adjust the meshing drive gears. They seem too loose with spacing a little too far apart. There's not a lot of adjustment to be had but take a look.














As you can see in the above photos, there appears to be too much clearance.



In the photo below, I pushed up the bottom of the gear and took all the slack out just to see what it would look like.





What do you think? Should I push the gears tighter together? And if so, how tight? Any advice appreciated.

 

[PHPaul]

Part of the answer depends on how much loading there is on the gears.

I agree that the original picture shows insufficient contact between gears.

IMHO, the last picture looks about right. As long as there is no binding and the load is relatively light, I'd say that was good to go.

 

[sixdogs]

Very light pressure on these gears. The gear is used to drive the eleven seed cups that drop seed.

 

[SPYDERLK]

The bearings are probably worn allowing the shafts to set a little further apart than their design position. Not critical that you fix it, but maybe easy and cheap enuf to do.
larry

 

[Utopia Texas]

I would leave 20 thousands gap measured with a wire feeler gauge to account for any expansion that might occur if the gears heat up. Generally gears that do not have much back pressure can be adjusted by seat of the pants until they run smooth and make little to no noise.

 

[jaotguy]

sounds about right ( smooth and little noise ) not quite as much as your last picture ....the teeth have some wear on them and would bind on the tips if you tried to snug them up too much ...

 

[Baby Grand]

I would leave 20 thousands gap measured with a wire feeler gauge to account for any expansion that might occur if the gears heat up. Generally gears that do not have much back pressure can be adjusted by seat of the pants until they run smooth and make little to no noise.

^ Run them close, then back them off until they quiet down and that should do it.
I'd guess the old breaker point gap of a paper matchbook cover (.016) would suffice.

 

[Hiltz]

Run a piece of typewriter paper or copy paper between the gears. Feed it slowly as you turn the gears and allow it to fully become engaged within the two gears. It will give you proper clearance.

 

[sixdogs]

How does this look, at least for starters? I made it tighter than it was but not as tight as my first photos. I didn't try the typewriter paper yet but understand the concept.

How does this clearance look? Tight enough? A little too loose?

 

[Utopia Texas]

Go by the smoothness and sound of the gears when moving. Getting a exact clearance from us on the Internet is impossible. Looks as if you are very good to go as it is now.