A G11 single piece worm block, $295 USD from Losmandy. Available very soon. Thing is you use your existing worm in the housing..
This would be fine if all G11's had the high accuracy worm, but not all do.
At $295 it's a lot cheaper than Ovision, $499 USD.
The reported improvement is 40% better PE. Mine is around 7 Arc seconds P to P thus expected improvement should see this lower to around 4.2 Arc seconds.
I was kinda was hoping for at least around 3 Arc seconds P to P or less...maybe I'm dreaming too much.
Last edited by wasyoungonce; 29-04-2010 at 02:04 PM.
I've followed the discussions on such things now and then, on the Losmandy Yahoo! group with interest, in case improvements are ever released for the GM8. Maybe one day they'll release improved worm mounting for the GM8.
If a simple modification can make such an improvement why is this not being done at the manufacturing level when you consider the price especially here we have to pay for these mounts.
Trev ide say that once losmandy actually releases the part for sale they will offer it as a "upgrade" option just the same as the different gemini levels.
Once ovision released this modification losmandy followed it for the service of their customers and for people who are brand loyalists (generally tak owners love to keep it in the family) and dont like mix N match components!
If a simple modification can make such an improvement why is this not being done at the manufacturing level when you consider the price especially here we have to pay for these mounts.
Well that is indeed a good point. It's been known for years yet they really only take action when Ovision is reaping the rewards.
IMHO the Ovision upgrade works so well, not because of their worm, but because of the one piece block. Probably this is why Losmandy is doing it without the worm.
But to consider why is Losmandy doing it now...competition? Will it be std on the new models...possibly, lets hope so.
Too much info to repeat the yahoo posting, but basic info:
$295 use your own worm & bearings;
40-60% reduction in PE;
76 sec tick fixed;
New coupling to gearbox.
Kinda doesn't really look like what I expected. I was expecting something like the Ovision set-up.
Looks like it couples directly to the gear box and is not really a one piece block but a number of parts screwed together to form a one piece block?
Edit:
Called: One piece worm block G11, HGM # 323-462-2855 to order.
Wow! That doesn't look right at all from what I can gather from this pic. It's a patch, not a solution IMHO. The oldham coupling has been changed to a more rigid attachement inline [good], the motor support is decoupled from the base plate [good] but the end blocks, although aligned, still can move independently? What's the point? It's a 'beefed up' holder/traverse not one block.
Me thinks Ovision will do well from this or Ovision may have a better pricing from the competition?
Lets wait & see for the results.
Well in the ovision design the motor is still attached to the base plate so it's no good either. And neither design incoporates thrust bearings either.
interesting design. Looks very complicated but has a lot of adjustment. I suppose time will tell if it takes over from the Ovision.
I looked at all the sales guff for both and went the Ovision route as it is tested and reasonably proven to improve. I haven't yet fitted it and wont be doing a before and after measurement. It will either be better than before or it won't. We'll see....
By the way..... The Ovision cost around $600 landed in Australia. It looks nice.
Why buy something unproven, when a proven solution is out there unless it's a lot cheaper. Next time I do a PEC run I'll take a screenshot of the residual PE. Hagar, put the Ovision in, beg or borrow PemPro (if you don't already have it, run the PEC run and you probably won't need to guide much if you're doing widefield stuff.
Did anyone end up getting the G-11 OPWB? I'm in LA at the moment and Chris at OPT just showed me one today. I'll heading back to OPT on sunday, and kinda wondering if it's worth bringing home. They reckon the results from local users as as-good-as Ovision. But that might just be sales speak??
I bought the Losmandy OPWB for my older G11 that had about 12 or 13 arcsecs of PE prior to the upgrade.
Due to the age of my mount I also had to upgrade the gearboxes. I originally bought 2 of the McLennan gearboxes which have had great reviews, and having seen them they are much better quality than the Losmandy ones. However, the McLennan gearboxes have a metric shaft and the Losmandy motors have an imperial diameter shaft, so the supplied Ruland coupling would not work, and it proved too hard at the time to source something that would fit, so I bought some of the standard Losmandy ones and fitted those instead.
My PE was reduced to 3.56 arcsecs peak to peak (see this thread), which just blew me away. Definitely a worthwhile upgrade in my opinion. I would still like to fit the McLennan gearboxes one day though nd see what difference it makes. But then again 3.56 arcsecs is good enough for me at the moment.
I will see if I can track down the PEMPro graphs before and after, and post them.
Adam
Last edited by adman; 12-11-2011 at 08:42 PM.
Reason: Corrected PE
Hey Adam,
Thanks for the reply. So you've pretty much convinced me to part with $300. I currently have +/-15 arc sec PE on an older mount. I have custom drives on the mount (SiTech). If I can just get 5 arc sec improvement it'll be worth it. Also the 76s PE that the OPWB addresses is much harder to guide out than the worm PE.
Cheers
I can't remember for sure - but I think the 76 second error is due to the original worm blocks being able to move independently of one another - so this upgrade will fix that. You still get 2 separate worm blocks but they are machined very accurately and are held into the OPWB very specifically by two screws per block. They will not move. If you have an older G11 (or the custom drives) you might want to make sure that the gearbox you have will suit, and then you might want some gearbox covers - as mine only had little slip-on rubber ones that won't work for the new setup
Also - I don't know if you read my thread above, but I had issues with the worm cover fouling on the main gear cover - this meant that the worm block would not seat properly. I ended up just filing it down, but it was a pain at the time. I don't know if Losmandy has fixed this or not, but I would imagine it is due to the age of my mount and slight design changes between it and newer ones.
EDIT: here are the before and after PEMPro graphs.
.
(generally tak owners 
love to keep it in the family) and dont like mix N match components!
