I got underway with my hypertune today. All went pretty smoothly although the RA shaft bearings were on pretty tight and took some convincing to get off - the original bearings will all be replaced with new ones.
I was pleased to find the source of slop in my RA axis - the shaft screws into the motor housing and is held in place with three set screws - these were loose and the shaft was not fully screwed into the housing.
I also found bits of metal mixed in wiht the grease in one of the bearings and the famous black grease in both worm mechanisms.
The spacers in both RA and DEC were cracked.
After a degrease I'm pleased to report that all the gears and worms were in excellent condition.
Tomorrow it's off to a friend with a lathe to ease the RA shaft slightly so assembly should be a bit easier. I'm waiting on some replacement hybrid ceramic worm bearings and spacers to arrive from the states then I'll be putting it all back together.
Nice photos Peter - really documents the process well. Hope it all turns out well. I was pleased with mine and thanks for all the advice, tools and help - it was very much appreciated.
Cheers Allan. I'm looking forward to hearing how yours performs. Here's my progress from today. Got the RA shaft eased by a friend who was kind enough to fabricate a bearing puller/pusher for the RA shaft for me. We also discovered more paint overspray on the RA shaft mating surface that has now been removed. The motor spur gear mesh has been adjusted.
This evening I completed the altitude mod and removed a heap of aluminium shavings from within the mount body. Here's the latest pics....
Interesting read. Could you tell me, is there anyone is Oz who performs this upgrade for a fee? I can fix cars, but I would definately bugger this up though lol
There are some astro shops that do this (Star Optics in Brisbane and possibly Bintel in Sydney?) however if you can fix a car you will easily handle this - get the instructions from Deep Space Products and take it slowly. It really isn't that hard once you get into it.
Thanks Troy. It was a combination of a high spot due to paint overspray and the set screws not being tightened down on to the RA shaft. I would never have found this without pulling it apart. The QC on these mounts is interesting - the machining is generally quite good however they leave paint in places where it really shouldn't be and fail to tighten set screws. I found this also in the altitude mechanism where one of the three set screws was not touching the pressure plate and the other two were really tight.
Today I'm going to check for burs and high points, install the main bearings in their housings and do the spacer measurements.
Here's today's progress...installed the new bearings in the RA and DEC housings and in both ring gears. The bearing puller made short work of it avoiding the need for sanding the housings to allow hand installation or use of a hammer.
I reset the altitude scale using a square to ensure the zero position was correct and cleaned the paint overspray off the worm housing surfaces to ensure the worm mesh adjustment is silky smooth. The stepper motors have also had the gear mesh adjusted.
I found an error in the Hypertune video where he determines the spacer thickness for the DEC axis he measures the height of the ring gear before he has installed the main DEC bearing - the spacer sits between the ring gear bearing and the main dec bearing and allows proper mesh of the worm and the ring gear.
I ended up staying with the 2RS style seals (same style seal as original). With the bearing installed in the heavy mount components the seal gets loaded and loosens up so I don't think it will be an issue.
My hybrid ceramic worm wheel bearings finally arrived today so a bit more progress to report. The worm mechanisms are now reassembled and feel nice and smooth.
I've also adjusted the mesh on the idler gear as per recommendations from the EQ6 group. The recommendation is to use a thin piece of paper to set the mesh clearance. I tried a few different thicknesses and settled on 0.07 mm thickness paper as this resulted in no noticable backlash without making the mesh feel too tight.
Hopefully my replacement spacers will arrive tomorrow and I can finish putting the mount back together (just in time for the clouds by the look of it).
Can you keep it disassembled for the weekend so we can all have clear skies for that. Once the moon gets to quarter, then you can put it all back together so the clouds roll in. Ok, thanks.
Can't wait til you get the spacers And the final adjUstments made to your mount. We'll have to make a comparison to the guiding and then you can fine tune mine. I think you can spend an age tuning the mount and then the software for the guiding before it all falls into place. In my case it will be knowing when to stop.
The photos look great and maybe you should write it up as an IIS resource
Well the spacers finally arrived today - can't understand why they took so long as they were posted on 6th Jan and marked air mail. Anyway I've now got both the RA and DEC axis back together. A few more parts to install and I can try it out - yippee!
Peter, you will have to come round and set up on my new deck. Just kidding as today I pulled out all the stops and poured the pier and did all of the decking. Must admit it looks fine and it will be interesting to see if your mount can do long exposures while guiding.
I should thank you as I was finally motivated to get the new observatory after doing the hypertune. Now I just need aset of narrow band filters to make it all worthwhile.
Well it's finally all back together now and I've spent quite a bit of time adjusting the worm mesh to minimise backlash. I tested it tonight (indoors) under full load and it seems to be slewing nicely. Friday night is looking clear so hope to get some time under the stars soon.
It was a very rewarding experience to pull it all apart, find the problems, correct them and put it back together. Thoroughly recommended if you have it in you.
Kudos on a job well done. Last year I did a similar rebuild on an Atlas EQ-G. The ceramic bearings are a must-have IMHO.
It looks like your hypertune is a step above most I've seen. Even after the work I put into mine I still had at least four high spots per axis. Paint overspray could have been the culprit for me too.
Your photos make me want to give mine another go around.