Is this worm gear knackered?!

[Dan13]

Hi I hope this is the right sub, I had some strange stiffness in the Dec axis of late so I'm currently going through a strip down and have bearings coming tomorrow. 

 

I've noticed on 10 of the teeth on the wrom gear seem to be flattened,  could this have been my issue or will it be OK to pop back in? 

Could I lightly file them?

I'm guessing most of the time the dec axis only move left to right but not by a hell of a lot when guiding so was thinking maybe sit that part of the worm up the top away from the worm gear if all else fails? 

 

Many thanks 

[bomberbaz]

Question I would be asking first is what caused it.

I think I would leave it for now, and if you can put it partially back together so you can see the cogs as it turns  then carefully turn and watch for the offending gears above engaging. Is that possible?

which mount is it btw.

I find in situations like this where cause of issue is unclear a series of careful testing and checking and re-testing as required is the best way.

[Dan13]

6 minutes ago, bomberbaz said:

Question I would be asking first is what caused it.

I think I would leave it for now, and if you can put it partially back together so you can see the cogs as it turns  then carefully turn and watch for the offending gears above engaging. Is that possible?

which mount is it btw.

I find in situations like this where cause of issue is unclear a series of careful testing and checking and re-testing as required is the best way.

I'm not certain but I have a feeling thinking about it now that I may have done this when stripping down but cant be sure. I think I may have been taking a bit a part but found with that section intact it was easier so tightend up the worm gears again so maybe there weren't alligned properly?! 

Its a HEQ5 pro. To my knowledge with this mount unfortunately I don't think you can watch the gears mating as its housed I csnt be sure but I rekon if I made that part the top part I don't think while guiding it will reach that bit much, I could be wrong. 

 

They do still seem to sit flush still and bind as the depth of the teeth is still there. 

If it really does cause problems I might just have to buy another and replace....

[Peter Drew]

It looks to me that the worm hasn't been engaging properly for some time.  The radius of the worm should match the curve of the teeth on the wormwheel.  The witness marks suggest that the worm has been running on the bottom of the tooth radius.  The "flats" on the teeth at the damaged area could have been caused either by the worm overriding the teeth or the worm being initially tightened against the crest of the teeth on initial assembly.  If this is the DEC axis wheel, just turn the wheel round 180 degrees so that the damage is on the opposite side.  If you are handy with a needle file you could clean up the flats.    🙂

[Dan13]

10 minutes ago, Peter Drew said:

It looks to me that the worm hasn't been engaging properly for some time.  The radius of the worm should match the curve of the teeth on the wormwheel.  The witness marks suggest that the worm has been running on the bottom of the tooth radius.  The "flats" on the teeth at the damaged area could have been caused either by the worm overriding the teeth or the worm being initially tightened against the crest of the teeth on initial assembly.  If this is the DEC axis wheel, just turn the wheel round 180 degrees so that the damage is on the opposite side.  If you are handy with a needle file you could clean up the flats.    🙂

Great news Peter! In a way anyway... yes I intend to keep them particular terth the opposite end to the worm gear and hopefully I'll barely go near them. My wide is a nail technician so may let her loose with them 😄  

Just got the RA one off now and looks fine so could have been me! 

One thing that's troubling me about putting back together is the worm gear adjustment at the end, I can't find a video on it and I definitely observe more with video then writing! 

 

Clear skies