sloz1664

Hi and a warm welcome to the Lounge.

Steve

It would be a hell of a lot cheaper to to get the pulley manufacturers to modify the pulleys for you.

And the money you will save can buy..................... Tak.........

Hi Gina,

Just a point to watch. there are two M42 threads. The old photograhic M42 x 0.75 thread. I think it's commonly called the Pentax screw thread. The other is the astro standard M42 x 0.5 thread.

I would contact Bern at Modern Astronomy, I have purchased both items from Bern earlier this year.

cheers

Steve

Just a had a bit of a shock. Went to place an order for two Spur Gears from HPC Gears..... Total cost £37.21. That's nearly the price of two full motors from Yuri. Considering you have to split the gearbox & fix it back together, which, as Max points out, could require three new pillars it's not viable. At present with Yuri's help motors are still available, if this dries up then HPC Gears would be an option.

As yet no reply from motor - semz regarding the Tal motors.

Steve

Sorry about that Alistair. I had ordered from Yuri before and it was a simple "repeat order".

You are probably wondering why I seem to go through so many motors. I had previously ordered two motors. On fitting the first motor I only just "nipped" the screws on the motor bracket, prior to any final adjustment. Set the axis for a timed one hour, to check if the clutches were correctly set, came back 15 mins later to hear an unpleasent clicking sound. The bracket had moved jamming the gears and resulted in the dreaded damaged final cog.

The second motor I damaged unaware that hand-controlling the mount while having the motor running DOES damage the final cog.

Best if you purchase two motors, you will then have a spare. Don't think, due to my misfortunes they are flimsy little things. They are Russian made. Built to last. Unless you're name is Steve.

If you require any details on how to obtain the motors, let me know.

Regards the HPC front. I will contact them to obtain total cost of the Cog. If reasonable I will order one, but I am a little uncertain on how to clamp the unit back together. Will have to think on that one.....

Cheers

Steve

I have had a reply from HPC Gears Ltd. The part number GO.4-32-SO4 Spur Gear (includes boring to 4mm) would replace the damaged drive cog. Price £12.18 + vat & delivery.

I have had one reply from Yuri, although he has sent two emails. I have sent three further emails, including western union funds for two motors - cost £45.50 (includes shipping) sent 21st Jan and, as yet, had no replies. Nor has Yuri collected the Western Union deposit. I will let you know on the proceedings.

cheers

Steve

Hi All,

Have checked the Final Cog and can confim with Andy the OD is 13.5mm, 32 teeth and a bore of 4mm. The shaft is always knurled to "key" the cog when it is pressed home. What you see inside the bore of the cog is the staked markings from the shaft.

I would be happy to use HPC ref: GO.4-32 cog it is thicker than the existing Tal cog and therefore more robust. I have my doubts on the current cog, in my opinion it's too thin, it's drive cog is chamfered and because of this does not mate fully across the width of the teeth of the final cog. As a precaution, just in case the tooth profiles are diffrent with both the Tal & HPC cogs, I will send one of my damaged cogs to HPC, later today.

NB: I have sent an email to motor - semz regarding the Tal motors.

Steve

Hi Andy,

Excellent link. I will strip down one of my old clock drives and measure the final cog, hopefully it will be similar. I will post the exact sizes for the existing cog and also send a drawing to HPC gears for them to quote.

cheers

Steve

Hi Andy,

Yes it's the final cog that's knackered. I now have three......

It is the one weak link in such a cracking little clock drive.

The final two cogs should have been case hardened, to toughen them up somewhat.

I will send a further email to Yuri and live in hope...

cheers

Steve

I have now a similar problem. I need a new gearbox for my Tal2 Mount (mashed teeth). I have contacted Yuri but not had a reply in 10 days. Is he still dealing with Tal spares or has his email changed for any reason. I last contacted him 8 months, with no problem.

cheers

Steve ago

Nice one Andy. I refurbished my Tal 2M mount earlier this year. Never looked back.

Cheers

Steve.