Go Back   IceInSpace > Equipment > ATM and DIY Projects

Reply
 
Thread Tools Rating: Thread Rating: 5 votes, 5.00 average.
  #21  
Old 12-02-2010, 06:38 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
Cheers Curt. I finally got to try it last night for the first time and I am very happy with how it is performing. I've been capturing pec curves and have +/- 5 arc second average PE according to PECPrep. I've also tried some 15 minute guided subs and have no noticable trailing - the best I could get previously was 2 mins.

Hoping to take some images tonight.

Peter
Reply With Quote
  #22  
Old 13-02-2010, 02:26 AM
opticalsupports's Avatar
opticalsupports (Curt)
Registered User

opticalsupports is offline
 
Join Date: Feb 2010
Location: Tampa, FL
Posts: 7
Fantastic. 15-minute subs is what hypertuning an Atlas is all about. I heard similar numbers reported from folks on the yahoo group, and their testimonials were what persuaded me to give it a try.
Reply With Quote
  #23  
Old 15-02-2010, 04:43 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
I know its all your fault that this weather is upon us, Peter.
+/- 0.005 arc second PEC and 95 hour subs doesn't cut it when its cloudy.......... Grrrrrrrrr.
Maybe we should take your mount out into a deep dark and lonely place and fill its bearings with sand and Vegemite so that the rest of us can get back to fumbling in the dark.

Glad to see that your efforts have paid off so well. Have to measure the PE of mine sometime when this cloud goes away... But I said that before
Reply With Quote
  #24  
Old 16-02-2010, 05:15 PM
leinad's Avatar
leinad
Registered User

leinad is offline
 
Join Date: Feb 2008
Location: Perth, WA
Posts: 1,307
Great work peter.. I'm thinking of acquiring on of these kits myself very shortly.

Did you get a chance to measure the PE prior to the work over?
Some have mentioned the Atlas/EQG-EQpro mounts having a +/-30 PP ?
Reply With Quote
  #25  
Old 16-02-2010, 05:54 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
Quote:
Originally Posted by leinad View Post
Great work peter.. I'm thinking of acquiring on of these kits myself very shortly.

Did you get a chance to measure the PE prior to the work over?
Some have mentioned the Atlas/EQG-EQpro mounts having a +/-30 PP ?
I'm not sure I would recommend buying the whole kit as the tools are pretty basic and the spare parts are readilly available. The instructional DVD's are quite good however there is an error in the DEC re-assembly bit.

I didn't measure the pre workover PE as there were some more fundamental issues with the mount I was trying to address. I was interested in the post PE to see if I'd done a reasonable job putting it all together more than anything.
Reply With Quote
  #26  
Old 16-02-2010, 05:59 PM
leinad's Avatar
leinad
Registered User

leinad is offline
 
Join Date: Feb 2008
Location: Perth, WA
Posts: 1,307
So the only worthy parts of the whole kit were the worm gear, and ceramic hybrid ball bearing kit? oh.. and extra spacers needed.
Reply With Quote
  #27  
Old 16-02-2010, 06:26 PM
troypiggo's Avatar
troypiggo (Troy)
Bust Duster

troypiggo is offline
 
Join Date: Nov 2008
Location: Brisbane, Australia
Posts: 4,824
Hey Peter,

I reckon it'd be extremely useful to make a post here about the best place to get the different parts instead of the kit. Like, if you had to do it all again, how would you do it and where would you get the stuff, links to the websites etc.
Reply With Quote
  #28  
Old 16-02-2010, 06:56 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
The basic kit only contains the spacers. You have to pay (quite a lot) more for the ceramic hybrid worm bearings. The bearings can be bought from VXB.com and the spacers are available from one of the members on the Yahoo EQ6 group. The kit doesn't contain a worm gear and you should n't need to replace this. The best part of the kit is the DVD's in my opinion.
Reply With Quote
  #29  
Old 16-02-2010, 07:11 PM
bojan's Avatar
bojan
amateur

bojan is online now
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,859
It is a pity you did not determine which component was contributing the most..
In my case it was transfer gears (47 peaks 2-3 arcsec in one period) and gearbox (last stage, 1:3, ~5arcsec pp).
Total it was ~35srcsec pp, after tuning (mesh) it is 23 arcsec pp.
Reply With Quote
  #30  
Old 16-02-2010, 07:24 PM
leinad's Avatar
leinad
Registered User

leinad is offline
 
Join Date: Feb 2008
Location: Perth, WA
Posts: 1,307
How did you conduct your test bojan; with Pempro ?
Reply With Quote
  #31  
Old 16-02-2010, 07:54 PM
bojan's Avatar
bojan
amateur

bojan is online now
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,859
Just 15 minutes exposure using 1000mm lens with slightly mis-aligned mount. Then I analysed the image pixel by pixel (tedious job ! )
I did not use the K3CCD then, unfortunately.

The images are after and before tuning (and replacement of motors and gearboxes)
Attached Thumbnails
Click for full-size image (PE_New_motors_13min_.jpg)
25.4 KB87 views
Click for full-size image (PE_OOB_15min_rot.jpg)
5.3 KB91 views
Reply With Quote
  #32  
Old 16-02-2010, 07:55 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
Quote:
Originally Posted by troypiggo View Post
Hey Peter,

I reckon it'd be extremely useful to make a post here about the best place to get the different parts instead of the kit. Like, if you had to do it all again, how would you do it and where would you get the stuff, links to the websites etc.
OK Troy here goes:

Spacer kit - join the Yahoo EQ6 group and find the post from Doug - he sells Delrin EQ6 spacer kits for US$13 including post to Aus.

http://tech.groups.yahoo.com/group/EQ6/message/32554

Worm Bearings (2 on each axis) - These are 608 deep groove ball bearings. The standard ones are steel but the recommendation is to get some hybrid ceramics. I got mine (ABEC7 ceramic hybrid low friction in a set of 8 for US$70) from VXB.com although I've seen posts where people got the same ones on ebay for less. http://www.vxb.com/page/bearings/PROD/Kit8344

There are quite a few different ceramic hybrid bearings to choose from apart from these - key is to get some good ones. I was told to go for ABEC 7 or ABEC 9 by someone I trust.

Grease - I got Superlube synthetic grease (3oz - 85g) from a local locksmith http://www.toplock.com/

It was about $10

http://www.super-lube.com/synthetic-...ease-ez-49.htm

I chose to replace the main bearings also although some say this is not necessary. I decided upon SKF bearings as follows:

6008-2RS1 - 6 in the mount although you can choose to re-use the original 2 DEC ring gear bearings as these don't rotate when the DEC clutch is locked
30206 J2/Q - 1 required
32208 J2/Q - 1 required

http://www.skf.com/skf/productcatalo...did=1050270008

http://www.skf.com/skf/productcatalo...did=1310000206

http://www.skf.com/skf/productcatalo...did=1310002208


All up these main bearings cost $179


You can get the instructions from Beevo for free although it isn't a step by step DVD:

http://www.beevo.com/rework.htm


You need the following tools:
a set of metric allen keys
a set of phillips head and straight screw drivers
a shifter
some needle nose pliers to remove the worm shaft covers and to adjust the wom thrust ring.
possibly some vice grips if the locking rings are done up really tight.

some fine wet and dry sand paper.
a craft knife for scraping paint off the mating surfaces.
a small length of 6mm ID tubing to rotate the worm shaft by hand.

Finally - a lot of patience when you adjust the worm mesh.

Peter

Last edited by peter_4059; 17-02-2010 at 07:25 AM.
Reply With Quote
  #33  
Old 16-02-2010, 08:04 PM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
Quote:
Originally Posted by bojan View Post
It is a pity you did not determine which component was contributing the most..
Based on my post tuneup PE curves, most of the PE is coming from the transfer gear and the worm (about 50% each). The transfer gear has an o-ring either side of the gear as a bearing and this is obviously not quite right. Luckily this is easy to adjust without pulling the mount apart again. There are also a number of modification options that can be looked at to replace the o-rings with spacers, or proper bearings. I just haven't got there yet.
Reply With Quote
  #34  
Old 16-02-2010, 08:17 PM
leinad's Avatar
leinad
Registered User

leinad is offline
 
Join Date: Feb 2008
Location: Perth, WA
Posts: 1,307
Thanks for all that information peter
Reply With Quote
  #35  
Old 16-02-2010, 08:18 PM
bojan's Avatar
bojan
amateur

bojan is online now
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,859
Quote:
Originally Posted by peter_4059 View Post
Based on my post tuneup PE curves, most of the PE is coming from the transfer gear and the worm (about 50% each). The transfer gear has an o-ring either side of the gear as a bearing and this is obviously not quite right. Luckily this is easy to adjust without pulling the mount apart again. There are also a number of modification options that can be looked at to replace the o-rings with spacers, or proper bearings. I just haven't got there yet.
Yep, this was my conclusion also, and it is quite visible on images above..
The transfer gears contribution can not be tuned out - I wanted to replace the gears with timing belts, everything is ready for the task but I do not have time...

PS: my mount is classic, with gearboxes (yours has only 200 s/r motors and transfer gears)
Reply With Quote
  #36  
Old 16-02-2010, 10:23 PM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
Peter and Bojan

which is the actual transfer gear you are referring to?
Reply With Quote
  #37  
Old 16-02-2010, 10:47 PM
bojan's Avatar
bojan
amateur

bojan is online now
 
Join Date: Jul 2006
Location: Mt Waverley, VIC
Posts: 5,859
I was referring to two 47-teeth gears - one is on the worm, another one is on the output shaft of the gear box of my classic EQ6 (gearbox with 131 reduction).
Also, I mentioned the last stage of the reduction in the gearbox that is 1:3, and the effect of this is visible as 3x higher frequency un the PE photos..

The Synscan EQ6 mount has slightly different reduction: 200s/rev motor, 12 (or 20?) teeth gear on motor shaft, then there is middle-size transfer gear (with rubber spacers?) and finally larger gear on the worm shaft. The reduction ratio is determined by gears on motor and worm axle [middle gear size (transfer gear) is irrelevant]

Last edited by bojan; 17-02-2010 at 08:50 AM.
Reply With Quote
  #38  
Old 17-02-2010, 07:23 AM
peter_4059's Avatar
peter_4059 (Peter)
Big Scopes are Cool

peter_4059 is offline
 
Join Date: Jun 2007
Location: Brisbane
Posts: 4,000
Allan,

On our EQ6 the transfer gear is the larger of the gears on the motor mounting. Mine has rubber o-rings and yours has a bush.
Reply With Quote
  #39  
Old 17-02-2010, 09:48 AM
allan gould's Avatar
allan gould
Registered User

allan gould is offline
 
Join Date: May 2005
Location: Brisbane
Posts: 4,481
Quote:
Originally Posted by peter_4059 View Post
Allan,

On our EQ6 the transfer gear is the larger of the gears on the motor mounting. Mine has rubber o-rings and yours has a bush.
Thats why I was confused as I couldn't remember anything with rubber O-rings in the mount.
Thanks for that
Reply With Quote
  #40  
Old 20-02-2010, 04:43 AM
opticalsupports's Avatar
opticalsupports (Curt)
Registered User

opticalsupports is offline
 
Join Date: Feb 2010
Location: Tampa, FL
Posts: 7
Pete, thanks for posting all of that info. It appears I will be following in your footsteps in the near future. Your thorough documenting of the hypertune is truly inspiring.

Where did you get the instructional DVD?
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 11:04 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
Bintel
Advertisement
SkyWatcher Australia
Advertisement
Lunatico Astronomical
Advertisement
OzScopes Authorised Dealer
Advertisement
NexDome Observatories
Advertisement
Meade Australia
Advertisement
Celestron Australia
Advertisement
Astronomy and Electronics Centre
Advertisement