EQ6 Died.

[Earl]

Back to the grinding noise.

I give up.

[moocher]

Grinding noise? Are the worms too tight?

Alan:D

[Earl]

Im guessing the RA has over-meshed again.

[Earl]

After some investigating the noise occurs when the stepper motor stops moving even though it should be.

[Earl]

Right after some looking im suffering from motor stall

[Earl]

After a bit of tinkering I have stoped the problem with the scope attached

The RA motor can be made to stall but this i presuming is a safety feature.

of course i bet my backlash and PE is all shot to bits.

[George]

I had the same problems, I have a high spot on the crown wheel and I'm guessing that with the severe cold the different metals that make up the gear train have contracted at different rates resulting in binding.

My solution was to stop the mount slacken off the clutch and invoke park, I kept doing this until the high spot was in an area I don't use, not very elegant but it does work

[Earl]

I had the same problems, I have a high spot on the crown wheel and I'm guessing that with the severe cold the different metals that make up the gear train have contracted at different rates resulting in binding.

My solution was to stop the mount slacken off the clutch and invoke park, I kept doing this until the high spot was in an area I don't use, not very elegant but it does work

I love the way the weather can be blamed for any eventuality

Its a fair point as its very cold, maybe a heating mod is needed

[George]

I love the way the weather can be blamed for any eventuality

Its a fair point as its very cold, maybe a heating mod is needed

Well I don't have the problem when its +C only when it -C

Doesn't make sense really metal contracts in the cold therefore the high spot should disappear and when its very warm should get worse. I lapped the gear train during the summer months and everything was perfect no binding whasoever anywhere in my slewing range.

[steppenwolf]

The RA motor can be made to stall but this i presuming is a safety feature.

I'd be a little careful about the motor stalling as I don't think this is a safety feature at all - I suspect that much current could be drawn and overheating could be the result of a stall.

[Moonshane]

wow these complicated mounts are as bad as dobs for needing mods

[Astro_Baby]

Motor stall sounds to me like the worms are too tight.

If your motor is rattling at start up or spool down that's probably due to resonance. You can tune it out by tightening the large brass hex nut on the top of the motor, be careful because there are small grub screws on the side of the motor that need to be loosened first.

To be honest it's not worth worrying about as it may make a cranky sound but it's won't be doing any harm if it is resonance.

My own experience with these mounts, which is becoming extensive , is that they simply aren't well enough engineered to ever be tuned 100%. For the money they are marvellous but your never going to get AP type performance from one.

[George]

My own experience with these mounts, which is becoming extensive , is that they simply aren't well enough engineered to ever be tuned 100%. For the money they are marvellous but your never going to get AP type performance from one.

Have to agree

You wouldn't believe how much backlash I have at the moment but providing its balanced slightly east heavy I have no problems with getting perfect guiding with PHD......when its windy thats another matter

[Earl]

I have it set up in my office atm, all seems ok atm.

[Peter Drew]

The bearing grease in these mounts can stiffen up in very cold weather, significantly increasing the load on the motors. The current "snap" might be pushing things to the limit.

[Dave S]

The bearing grease in these mounts can stiffen up in very cold weather, significantly increasing the load on the motors. The current "snap" might be pushing things to the limit.

I agree the grease that manufacturers use is often pretty rubbish. It tends to form a stiff paste after time. Could be worth a strip and re-grease, worthwhile even if it doesn't cure the problem.

Dave...

[George]

Mine was re-greased with Du-Pont teflon grease......good down to -40C , if we see temps that low in the UK my mount will be the least of my worries

[Astro_Baby]

A strip and regrease with white lithium worked wonders for my HEQ5, careful tuning has also meant its VERY quiet and with next to no play or backlash. But on the downside tuning the HEQ5 is a nightmare and it needs to be 'fettled' as initiual tuning is always a bit off, you have to work on it progressivley.

The EQ6 by comparison was a lot easier to tune BUT its a complete swine to dismantle.

[Earl]

so far so good today, I have had my scope setup in my office (front lounge aka man toy room )

It has been slewed set to track slewed and the such without any problems.

I think im going to let this cold spell pass before i take it out again.

[Earl]

or i could get my mount one of these pop in a few dew heaters....talk to it nicely...

[Helen]

I've got a dewstrap wrapped around my filter wheel to keep it working in these temperatures (seems to have cured the problem!). Perhaps FLO could persuade Blazewear to do mount coats

Helen

[barkis]

What about a Tea cosy jacket to wrap around the mount during the severe cold spells. Nichrome wire to output 5 watts at 12 volts,

less than .5 Amps. Slots provided for the cables. Similar to Earls little dog's coat .

Keep the dew off too, I'm sure it must form inside as well as outside the housing.