¿ªÔÆÌåÓý

  1. Losmandy_users
  2. Messages
Single Messages Topics Expanded Polls

Re: What result I can get with the current OPW in my old G11?

 

Andre,

You are not buying a Rolls Royce or a Bentley auto, or an AP or 10-Micron, etc. mount.
You are buying a stock mount.? Each mount maker has its own unique design qualities that set it apart from the rest of the market.??

You must assess the suitability of the mount you bought for your purposes -- your telescope, your camera, your imaging desires for perfection.

If you find the stock mount does not meet your expectations, you can either
? ?do not make any changes and return it for a refund
? ?decide to upgrade its parts to more superior ones

The stock G11 or GM8 mount does not have any guarantee on its PE.? It does not have any published spec on its worm bearings or other parts.
The mounts vary in performance.? The mounts are not all tested by the factory under the stars for PE performance.? Many owners have obtained about 1 arcsec RMS PE on their G11 mounts, and about 2X that for the GM8 drive.? I would say this is proven...possible, but not guaranteed.??
??
In this group, other owners are explaining what we have done to obtain superior performance from our stock mounts.
That is why you see a large variation in approaches, with new gearboxes, bearings, lubricants, adjustments, and even homemade OPW systems and stepper motor systems.??
This is considered by us owners to be another of the great challenges of this hobby.??
Do not take any advice as gospel; your mount may have a different issue than other owners have faced, or it may have the same common issues that many mounts have experienced.? However, the company does change its designs, as its website says " ALL SPECIFICATIONS MAY AND WILL CHANGE WITHOUT NOTICE? "??

The stock parts that Losmandy offers are also subject to design changes.? For example, the original OPW was long, bolted on the gearbox, and had 3 worm bearings.? Later OPW were shorter, have 2 bearings, and do not attach the gearbox.? Still later mounts came tucked motors and after that came the SLW spring loaded worm version.? Each modification in design was intended to solve some prior issue.? ?We know that new changes have good intentions.? Only testing can show if those intentions are realized.??

For those with considerably more financial resources, there are mounts of much higher precision available, at their cost point.

Enjoy the many challenges of this great hobby.? I would not expect perfection from any mount, any telescope, any camera, or any software.? New products and new inventions come on the market regularly.? If there were a perfect unit, there would be no further inventions.??
Perfection lies in the future...not the present.? You are part of the future improvements if you find better approaches than those reported already.

Stay well and enjoy the journey forward,

Michael




On Fri, Jul 30, 2021 at 7:44 AM GuitsBoy <guitsboy@...> wrote:

Hi Andre -

If you purchased a one piece worm block with high precision worm, and it came assembled with bearings, then you should be fine on that axis.? As far as I know, Losmandy only seems to have one tier of bearings.? However for the HP brass worm you purchased alone, you may want to replace the old bearings on that axis.?

The Losmandy bearings are indeed high quality, and as best I can figure they are ABEC7 japan made parts (EZO brand, I believe).? However I have had very good luck with inexpensive PGN? R4 bearings (ABEC 5) from amazon, I believe they were $10 for a sleeve of ten.? There are a number of other sources for ABEC5 and ABEC7 bearings, hopefully that ship to your location.

As for replacing the bearings, I found putting my old two piece bearing block in the toaster oven for five minutes at 325? F allowed them to drop right out, as the aluminum bearing block expands more than the steel cartridge bearing.? It was much easier than trying to press/pull them out.




On 7/30/2021 10:27 AM, andre_moutinho wrote:

Hi John,

?

Thanks for your reply.

>>If you just ordered new ones from Losmandy, you should be OK

?

I did not understand this. I have ordered the OPW that currently comes with new bearings. So I should have ordered other higher quality bearings from Losmandy? The bearings that comes with the OPW are not good enough?

?

Best Regards

Andre

?

?

De: [email protected] [mailto:[email protected]] Em nome de John Kmetz
Enviada em: quinta-feira, 29 de julho de 2021 22:53
Para: [email protected]
Assunto: Re: [Losmandy_users_io] What result I can get with the current OPW in my old G11?

?

On Thu, Jul 29, 2021 at 08:50 AM, andre_moutinho wrote:

You say I need replace the just acquired OPW bearings?

Andre,

Most people who do a mount rebuild usually replace the bearings at the same time. They are inexpensive and therefore disposable. If you just ordered new ones from Losmandy, you should be OK. When inserting into the worm block, use care to press in evenly with pressure or gently tapping on the outside race only. If you press on the inside you can bend them, or if inserted on an angle, they can be warped out of round, and you can create the dreaded 76 second error, where the balls are not riding smoothly between the inner and outer races.

Also the bearing should slide smoothly with finger pressure over the brass worm and should not be forced in or hammered in. One new brass worm I received was very slightly oversized, and I used 400 mesh sandpaper to gently twist and polish the end down until the bearing would fit over.?

Usually I have several new bearings on hand, just in case of any mistake, or possible damage during insertion, or guiding errors that could develop later.

Best Regards,

John



--
Michael Herman
mobile: 408 421-1239
email: mherman346@...
Join [email protected] to automatically receive all group messages.