sabir
professor emeritus
Reged: 06/23/07
Posts: 698
Loc: Pune (India)
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I thought I’d finally get down to it and start this thread, which I’ve been planning to start since a few days. I’ve read about this mod. being done by several people but I was unable to find sufficient data dealing with this topic, particularly for intelliscopes
So here are a few questions I have from the top of my head...
1. I’ve read that installing a Lazy Suzan bearing makes the azimuth movement too free (weather wane syndrome!  ) and hence some sort of friction mechanism needs to be employed. I know the light bridges use a spring loaded center bolt for varying tension, but this obviously cannot be used for the intelliscope... so any ideas which work would be really welcome.
2. I have read that the ball bearings have a tendency of developing flat spots, making it a click-stop azimuth. For all the people who have installed these bearings and have been using them for a while... How are the bearings holding up??
3. If flat spots are posing a problem, has any body experimented with cylindrical bearing surfaces as opposed to ball bearings i.e. line contact as opposed to point contact??
4. After installation of these bearings, does the scope become sensitive to the leveling conditions of the ground?? I intend to use the scope with a Round Table Platform down the road. Would this pose to be a problem??
5. Finally, sourcing these bearings. I have found several vendors who offer similar bearings i.e. 12” Dia, and 5/16” overall thickness. Are these the ones to be used with the intelliscopes? I would like to find a bearing, which has the right thickness for the intelliscope to work without the encoders requiring shimming...if possible
Here are the links I found:
http://doitbest.com/Kitchen+organizers--model-212482-doitbest-sku-212482.dib
http://www.rockler.com/product.cfm?page=2273&filter=lazy%20susan
http://www.rockler.com/product.cfm?page=2273&filter=lazy%20susan
Here is another great link for all intelliscope systems. It has all the information on the intelliscope system you’ll ever require and more!! 
At the bottom of the page there is a drawing giving all the dimensional details required for the azimuth assembly.
http://maxwell.fief.org/intelliscope.html
I would encourage everybody, especially the path beakers who have pioneered this mod. to participate in what ever way possible be it pictures, links, suggestion or advice and hope fully, with your help we can make this a one stop thread for the Lazy Susan mod for intelliscopes and by and large for all dobs.
Thank you all!
Sabir 
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No one can attain good livelihood-even if he is so lucky - without passing through misfortunes. Days will usurp the opportunities of those who waste today's opportunity due to their expectation of tomorrow's opportunities. Day's custom is the usurpation of opportunities and the habit of time is wasting them.
Imam Ali (a.s)
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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I've installed the "Do it Best" bearing on my XT12i. While this is a new mod for me and I can't answer regarding long-term use the thickness was perfect, at least for my encoder. It does make the azimuth too easy and some form of braking is needed in addition to the lazy susan bearing. Right now I'm experimenting with center bolt and I'll go into more detail if that works out. I know leaving the teflon pads installed will add considerable friction to the movement so perhaps leaving one or two might be the right answer.
As far as the lazy susan bearing developing flat spots over time; I'm not sweating that. The bearing, once placed is easy and cheap enough to replace.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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Buck
professor emeritus
Reged: 04/29/05
Posts: 564
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To add a little drag to the AZ movement you can use a few small pieces of cut loop carpet to the bottom of the rocker box. Just trim the carpet till it is still a bit much and it will ware-in in a short while.
Buck
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sabir
professor emeritus
Reged: 06/23/07
Posts: 698
Loc: Pune (India)
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Hi Jim,
I too am looking the "do it best" bearing as they also stock the #08200 magicsliders (I plan to use these a the breaks) which saves me shipping and are supposed have the right height for the intelliscopes. I'm really glad to hear that you found the thickness to be perfect!!
Have you tried using your XT12i on a sloping surface after the mod? I would like to find out if the shift in the center of gravity of the scope due to the slope has any effect on the performance of the bearing.
Do keep us updated on how your break mechanism goes.
Thanks again,
Sabir
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No one can attain good livelihood-even if he is so lucky - without passing through misfortunes. Days will usurp the opportunities of those who waste today's opportunity due to their expectation of tomorrow's opportunities. Day's custom is the usurpation of opportunities and the habit of time is wasting them.
Imam Ali (a.s)
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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I've not tried my scope on a sloping surface. I live along the coast and you have to look for something other than flat ground. I've no doubt that the lazy susan bearing by itself will allow the scope to both blow in the wind and point downhill.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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DanJ
Pooh-Bah
Reged: 12/01/04
Posts: 1088
Loc: Youngsville, NC
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Sabir,
The 08200 Magic sliders will do the trick. They continue to work great on my xt8i and I have been using them for almost two years now.
Cheers,
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Dan J.
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XT8i
ETX 90
PST
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"A government big enough to give you everything you want, is strong enough to take everything you have."
Gerald Ford
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Jim7728
Postmaster
Reged: 04/10/05
Posts: 5060
Loc: Stoop Landing Observatory, NYC
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Sabir
I've used "lazy susan" bearings for my homemade dob base.
I had the first one you listed:
http://doitbest.com/Kitchen+organizers--model-212482-doitbest-sku-212482.dib
And it work fine(smooth motions) for a few years until one or two ball bearings got out. I've since went with a better quality 12.75 "Lazy Susan $22.50
Aluminum Lazy Susan Bearings
This one feels a little smoother and better built than the $10 one. No issues with the weathervane effect, but my 12.5" sonotube dob is heavier than the Intellescope metal tube and like Buck said, if you want to add resistance, a piece of carpet or felt will work fine.
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Jim
TV-60/40mm Ha-5mm BF
FS-102 and other tubes...
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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The main problem, as I see it, with modifying the Az on the Intelliscope base is that if you get it wrong, and the Az encoder disc magnetic strip comes into contact with the encoder board, you immediately wipe out the two tiny electronic sensors that protrude slightly above the Az board!
The working clearance between the magnetic disc strip and the two electronic sensors is of extremely close tolerance anyway,for this system to operate properly, and there just isn't any margin for error.
This catstrophy occurs without any warning the instant that you rotate the base! The two tiny sensors, look like two black dots and are micro soldered to the Az board circuitry.
These are so delicate that they are actually wiped clean off of the Az board and usually leave a scrape in the Az disc black
strip. A new Az board and possibly a new magnetic disc must be ordered from Orion, as the COL function is now inoperative...Been there, Done that...LOL!
Just scratching the magnetic strip on the Disc. won't hurt it, but if you've bent the disc badly, you either have to try and straighten it out, or just order a new disc, along with the new Az board.
Two simple raised barrier strips, just a hair higher than the sensors, and glued to the board adjacent to each of these two miniature electronic sensors would eliminate this problem,making it physically impossible for the Disc strip to come into contact with the two sensors . A tiny piece of hard plastic or other non magnetic substance would do the trick!
I did contact Orion Tech support suggesting this fix, but I don't know if they passed the Info. on to the Mfg. of the Az board.
Bob
12" F/4.9 Intelliscope with COL
10" F/5.0 Coast Inststrument Treckerscope,circa 1956
Stratus 35mm( hand grenade ) Nagler 22T4, 17T4, and 12T4
BO/TMB 7mm and 5mm, TeleVue Paracorr.
Barlows: GSO 2"ED 2x, Orion Shorty Plus 2.2X, TeleVue 2.5x, Coast Inst. 3x
Edited by Bob W6PU (05/22/08 01:41 AM)
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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After re reading my post of last night, I want to add this.
I think that Before anyone does any serious base modification that will alter the spacing between the Az encoder board sensors and the magnetic disc, that they really examine and get to throughly understand the mechanical relationship of the rotating disc and the pick up sensors.
Hold the board in your hand and observe how the magnetic disc rotates above the sensors on this board, and note how close the disc magnetic surface normally comes to touching these Az board sensors!
After reading this long thread, I was frankly amazed that no one has picked up on this very common problem, and added any comments!
It makes me wonder just how many have actually done any serious modification to the Intelliscope base azimuth movement, such as adding a roller bearing system to replace the existing Teflon Az sliders.
I have done so, but have found that the adjustment of same is so critical to avoid damage to the azimuth board sensors, that I will not post this Mod.
The problem that I described is an accident just waiting to happen, and should probably be permanently attached to this Reflector Forum!
I hope that I've helped some Intelliscope owners from damaging their COL function!
Cheers
Bob
Edited by Bob W6PU (05/22/08 01:43 PM)
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jayscheuerle
Post Laureate
Reged: 01/16/06
Posts: 4034
Loc: S. Philadelphia, PA
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Quote:
I would like to find out if the shift in the center of gravity of the scope due to the slope has any effect on the performance of the bearing.
My LB has roller bearings. Before I had it properly balanced (and relied on the brake to hold it), the scope would rotate its nose to the low point on my EQ platform. Once balanced, this no longer occurred.
The LB ads tension to the rollers via the center hub-nut. There's a large knob on top. Just righty-tighty when it's windy.
The scope's a pleasure to move. - j
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Walk purposely with a concerned expression.
The Green Goblin - 12" of dobsonian excellence!
The PortaBowl-a $100 4.5" f/8 ball-scope YOU can build!
Eero2-a 6" f/5 ball-scope you probably can't. 
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dmgriff
sage
Reged: 09/20/06
Posts: 332
Loc: 30 degrees latitude, USA
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I used a lazy susann similar or same to the doitbest 12" on a 6in dob no col. I found the movement sporadic at best, the ball bearings tended to bunch up, and teflon spray did not stop the bunching. I did not try any thick grease as I did not want to attrack dirt.
Went to new Virgin Teflon pads on the 6. Works well.
Several vendors have been offering virgin teflon pad and true ebony star laminate kits (one among them is scopestuff.com az kit ). There have been some threads in CN forums about applying ptfe pads and ebony star to xti intelliscopes with col.
Just my opinion, but, I think the ptfe and ebony star will give you custom dob az motion, as many use it for the az, and ebony star laminated to the alt beartings.
I just never had any luck with the hardware lazy susann approach, it may have been the weight of the 6in, dont know.
Good viewing,
Dave
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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I have ripped up the board sensors trying the "CD on the center bearing" trick but now I'm older and wiser. BTW, three cheers for the Orion support team who sent me a new AZ encoder assembly free of charge (I can imagine them saying, "yep another one tried the CD").
I measured the thickness of the teflon pads and work within plus or minus a baby's hair of that. So far so good.
It sounds as if DMGRIFF may have gotten a bad bearing. Another possibility is that it is not centered and so begins to bind through some of it's travel. I was concerned about lubricants holding dirt also and used graphite dust (look at a sewing shop) to lube the susan bearing and that seemed to work just fine.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
Edited by epee (05/22/08 05:24 PM)
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dmgriff
sage
Reged: 09/20/06
Posts: 332
Loc: 30 degrees latitude, USA
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epee,
Measured it as best I could, clickity clack movement, at best. Just my personal experience.
I have the gso roller bearing system on a DSH10, and it is not a lazy susann type mechanism, very smooth.
I have tried every inexpensive hardware store mod from gliders, amourall lube, teflon spray, and the lazy susann and none, absolutely, none, work for me.
At 10usd or so the lazy susann is easy enough to install for experimentation, though.
Good viewing,
Dave
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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I understand. It seems that virgin teflon solved it for you. The bearing I'm using is certainly smooth enough; now I need to create a touch more sticktion. If I have too much trouble doing that it's the laminate kit for me.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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dmgriff
sage
Reged: 09/20/06
Posts: 332
Loc: 30 degrees latitude, USA
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The felt furniture pads will definitely cause sticktion. Maybe too much.
Good viewing,
Dave
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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Quote:
I have ripped up the board sensors trying the "CD on the center bearing" trick but now I'm older and wiser. BTW, three cheers for the Orion support team who sent me a new AZ encoder assembly free of charge (I can imagine them saying, "yep another one tried the CD").
A CD or "milk jug" washers on the center bearing can be disastrous when used on the Intelliscope center bearing as any slight amount of over thickness causes a "high centering" condition that allows the upper half of the XTi base to rock or wobble in respect to the fixed lower base section!
This results in a off center pressure on the edge of the magnetic disc which then presses against the two Azimuth Board Sensors and tears them right off of the board!
I would never again replace an azimuth board without first protecting those two electronic "black dot" sensors with something like a glued on thin non magnetic washer that physically prevents the sensor from making contact with the magnetic disc!
One way of dealing with dealing with any wobble or rocking of the two base sections is to leave just enough thickness in the three Teflon base pads so that a "lazy susan" bearing assembly is taking most of the weight, with the base edges just barely "grazing" the three Teflon pads.
Those two raised "black dot" sensors on the Az board are an inherent design weakness in this system, and I just can't understand why the Mfg. continues to make the Az board this way, if indeed they still do?
Oh yes, ditto on the understanding Orion Tech Support Team.
I must have replaced three AZ boards within a couple of months, before I "wised up" as to what was going on, and what to do about it...I felt like a complete idiot, and offered to pay for the new boards, but as my scope was still less than a year old, they wouldn't take my money!
I sure hope that my Azimuth Board design change suggestion was passed on to the Mfg of those boards, this was around last Sept and Oct.
Cheers!
Bob
Edited by Bob W6PU (05/22/08 07:36 PM)
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chalker
professor emeritus
Reged: 09/14/05
Posts: 604
Loc: Ontario, Canada
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Quote:
.... I've since went with a better quality 12.75 "Lazy Susan $22.50
Aluminum Lazy Susan Bearings
This one feels a little smoother and better built than the $10 one.
Boy the second aluminum bearing you linked to looks nice. I wonder what the internal diameter is, since it has rotating rings written all over it.
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Orion StarMax 127
Meade Lightbridge 10" Deluxe
Toronto CSC
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calan
sage
Reged: 06/16/07
Posts: 457
Loc: Oklahoma City, OK
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Wow... I just posted about this in another thread. Should of known I wasn't onto something original 
I used the standard Lazy Susan bearing, lubed with some silicon spray. Adjusting the amount of "freedom" is simple; Place a nylon spacer and/or washer on the center shaft so that it that sits about 1/64" below the top of bearing (use a straight-edge across it). You want the spacer to be barely below the base (about 1/64"). Then put a big fender washer under the lock nut on top of the base to help spread out the nut's clamping force a bit.
You can then slightly tighten the lock nut (and thus transfer friction from the nut/shaft to the base) to get any amount of drag you desire. If you keep tightening, you will begin to tighten the base down onto the spacer, producing even more drag without crushing the bearing or cracking the base. I can adjust mine from extremely free spinning to almost locked down.
Edit:
I just checked the links and the "doitbest" version is the one I've had kicking around in my garage for years and the one that I used.
BTW - These things are rated at 1000 lbs, and the load is spread out over many ball bearings. Unless it is severely over-loaded, abused, or defective, I can't see it developing flat spots any time soon. Time will tell though
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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It sounds as if you've done something similar to what I'm planing but can you explain that, "1/64" below the top of the bearing" a little clearer please?
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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Calan,
So let me see if I've got this right. You've placed a nylon washer on top of the brass center bearing so that it comes to just below flush with the base. The lock nut then presses a fender washer down on the nylon washer to produce the friction you want?
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
Edited by epee (05/23/08 10:59 PM)
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sabir
professor emeritus
Reged: 06/23/07
Posts: 698
Loc: Pune (India)
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Thanks Guys for the replys!
It looks like the 'Do it best' bearing fits the bill quite nicely.
Jim,
the 'Aluminium Lazy Suzan Bearing' look really nice, but I'm afraid, it would increase the spacing a bit too much for the azimuth encoder to work. The spacing required is about 6.25-6.5mm. The Aluminium bearing has a thickness of 12.7mm whereas the 'do it best' bearing has a thickness of 7.9mm, so I guess it fits the bill better.
Any body else with any suggestions/feed back??
Sabir
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No one can attain good livelihood-even if he is so lucky - without passing through misfortunes. Days will usurp the opportunities of those who waste today's opportunity due to their expectation of tomorrow's opportunities. Day's custom is the usurpation of opportunities and the habit of time is wasting them.
Imam Ali (a.s)
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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Once you have the bearing in your single biggest issue will be adding stiction or a brake to stop the OTA from spinning at the slightest amout of force. That's a problem I'm still battling and the COL encoder complicates things considerably. I don't understand calan's solution; my center bearing protrudes above the rocker base. Perhaps I'm being to fussy and a simple block of carpet or foam would do the trick but adding stiction is definately something you're going to have to deal with.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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UKJim
member
Reged: 11/27/07
Posts: 35
Loc: Grantham, Lincs, UK
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Sabir,
I have created a page on my site regarding the Azimuth Bearing problem:
Jims Orion XT10 site - Azimuth Bearing friction/stiction and mods
I too have added a lazy susan and have detailed the part number and my intention is to create a page detailing the mod. Sorry its not done yet (its on my todo list!). 
With regards potential damage to the sensor, the brass bush is designed to ensure the correct critical gap is maintained between magnetic disc and sensor surface for the IntelliScope to operate properly. Problems only occur if poor assembly results in the two base parts becoming skewed off axis, i.e. perhaps the central nut is not done up tight enough which allows too much wobble of the two base sections to each other. If anything a lazy susan makes this less likely to happen since it provides a wider diameter for support of the top base onto the bottom.
Other notes are in agreement with other posters, i.e. the scope now rotates incredibly freely, and I need to implement a braking mechanism (such as carpet!), otherwise even the wind will blow it round, and/or my movement near the scope has to be careful.
The bearings do have a notching effect sometimes, i.e. you move the scope but the bearings want to roll it back or fore slightly before it rests. This might be due to me making a silly mistake when installing the lazy susan. I drilled mounting screw pilot holes, with the bearing in place, and blew the resulting sawdust away, but some got into the ball bearings! Ooops. 
So something to be careful of for would-be modders.
This could account for the idea of "flat spots" mentioned by you, meaning they are NOT flat spots, but more likely to be dirt or particles which have got into the bearings. I think the low cost of the lazy susan might warrant a 2-yearly renewal?
I do sometimes feel that the Teflon pads and stiction approach, if maintained well, offers better control for wide viewing. Its just the high magnification that requires the smoothness of a ball bearing.
I'm sure Dobsonian designers have considered ball bearings but felt that Teflon was a better approach. I don't think Teflon is particularly a cheaper method, unless high quality lazy susan were used.
Generally I much prefer the smoothness of the lazy susan, but it can sometimes be annoying having to move so gingerly around the scope if I have aligned it on something, and want to change the eyepiece for example (must sort out that brake).
The LS I used raises the top baseplate above the teflon pads by about 1.5mm so the pads are no longer in contact. This also means the mod is non-destructive - I can remove the LS and have it working in the normal Teflon way quite easily.
Some additional notes and pics on this page might be of use also:-
Orion XT10 - Azimuth Bearing Assembly
Jim
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Orion XT10 Intelliscope with COL.
Low-Profile Crayford+AccuFocus
Orion 25mm, 10mm Plossl EP's
Baader Hyperion 13mm 68deg with 14 & 28mm FTR's
Adler Optik Skarp 38mm(32x)2" 5 EL SWA 70*FOV
Orion Shorty-Plus 3 El. 2xBarlow
Baader Laser Collimator. 13% Moon filter.
Binos: Super Zenith 10x50 7deg FOV, Adler Jupiter 20x80ZCF and Fumoto 10x25
Laptop+Stellarium, Starry Night, ECU.
My site dedicated to the www.Orion-XT10.com
Edited by UKJim (05/28/08 10:00 PM)
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UKJim
member
Reged: 11/27/07
Posts: 35
Loc: Grantham, Lincs, UK
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At last I have finished my detailed page on the Lazy Susan bearing mod, which I have added to my Skyquest XT Mods page in my web site......
XT Mods - Addition of a Lazy Susan turntable bearing on Orion Skyquest XT telescopes
My page provides lots of photos, and detailed explanation of the procedure, and discusses some of the concerns raised on this thread.
Hope some folk find it useful!
Best wishes
Jim
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Orion XT10 Intelliscope with COL.
Low-Profile Crayford+AccuFocus
Orion 25mm, 10mm Plossl EP's
Baader Hyperion 13mm 68deg with 14 & 28mm FTR's
Adler Optik Skarp 38mm(32x)2" 5 EL SWA 70*FOV
Orion Shorty-Plus 3 El. 2xBarlow
Baader Laser Collimator. 13% Moon filter.
Binos: Super Zenith 10x50 7deg FOV, Adler Jupiter 20x80ZCF and Fumoto 10x25
Laptop+Stellarium, Starry Night, ECU.
My site dedicated to the www.Orion-XT10.com
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sabir
professor emeritus
Reged: 06/23/07
Posts: 698
Loc: Pune (India)
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Hi Jim
Thats a great site you've got there!! In fact I had found it to be a great help even before you updated it with your lazy-susan Az mod. 
I'm sure a lot of people like me will find it to be very useful
Sabir
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No one can attain good livelihood-even if he is so lucky - without passing through misfortunes. Days will usurp the opportunities of those who waste today's opportunity due to their expectation of tomorrow's opportunities. Day's custom is the usurpation of opportunities and the habit of time is wasting them.
Imam Ali (a.s)
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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Very nice work there Jim.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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Enjoyed your nifty site Jim!
Just wondering, how many encoder boards did you have to replace due to ruined sensors before you got it right, as I did, By Trial And Error?...LOL! I went through three of them!  ....Very Stressful!
There is absolutely no warning, and the sensors are wiped right off of the board by the pressure of the magnetic strip digging into them, as soon as you start to rotate the base! You can't see it or measure it, and it happens faster than a 1000Amp. short!
The first clue is that you no longer have any changing Az readings on you COL, and the COL function no longer works. This is very tricky business Jim, and I don't recommend it unless some sort of protection is provided to the magnetic sensors, such as a raised barrier as I mention in this post.
I wrote a suggestion to Orion Tech, services suggesting that a small hard plastic raised barrier be placed either side of each sensor to make this destruction impossible. It would only have to be a fraction higher than the sensors themselves. The worst that would happen was that you dug into the magnetic strip, when it slammed into the protective raised barrier, which wouldn't do the strip any harm, just gouge it which wouldn't effect its operation unless you really peeled it off!
Cheers!
Bob 
Edited by Bob W6PU (09/03/08 05:48 PM)
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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The more that I read this thread, the more that I feel that Orion really needs to have their own "technical" website....let's see now, they could call it..."The Doctor Is In"
Their Intelliscope series really brings this home, in that they sell a line of Dobs with superior optics, and an amazingly accurate COL, but one that uses a flawed base, and has undersized altitude bearings.
Oh sure, we amateurs can experiment and correct this Azimuth flaw, but, IMO, instead of ignoring this issue as Orion seems to have done, they should address this problem and offer their own solutions perhaps in a news letter or a technical bulletin sent out to all registered owners!
The Lazy Susan solution is a fine one, if it is done correctly,( and we have to experiment to find how without destroying Az senors) and again,in my opinion, Orion should be right on top of this! I'm sure that they must be sending out these Az sensor boards like pop corn!...LOL!
Another accident waiting to happen are the magnetic senors on the azimuth board. It would be so simple, and inexpensive to protect them, and yet, they have done nothing about this situation except to provide you with a new Az sensor board.
I realize that Orion does not manufacture these, but couldn't they at least pass this on to those that do?
I am a great fan of Orion, and have passed along technical suggestions, which seem to be ignored.
Apparently in their new XX model, they have improved the base Az problem as well as added larger diameter Alt bearing for smoother altitude operation, so perhaps they don't ignore all suggestions!
I have moved away from the lazy susan approach, removing same, and instead using the Scope Stuff Formica ring and new "Virgin Teflon" sliders.
The Lazy Susan bearings were constantly getting "gunked up" in this windy NM high desert environment, and required constant degreasing/cleaning, and relubing of the bearings!
Another must is to attach the magnetic disc. to the base with a few dabs of quality contact cement. This solves once and for all the problem of azimuth encoder slippage with the resultant need to constantly be re tightening the main center bolt...LOL!
Cheers!
Bob
12" F/4.9 Intelliscope with COL
10" F/5.0 Coast Instrument Treckerscope,circa 1956
Stratus 35mm. Naglers 22T4, 17T4, and 12T4. BO/TMB 7mm and 5mm. TeleVue Paracorr
Barlows: GSO 2"ED 2x, Orion Shorty Plus 2.2x, TeleVue 2.5x and 3x.
Edited by Bob W6PU (09/04/08 01:24 AM)
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Bob W6PU
Carpal Tunnel
Reged: 12/23/04
Posts: 2200
Loc: Springer-N.E.NM
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Hey folks, I hadn't realized that this was an old thread until I got off page 2 and saw my previous comments on page 1 Oh well, it can't hurt to repeat good advice.LOL!
Bob
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John Carruthers
Skiprat
Reged: 02/02/07
Posts: 2258
Loc: Kent, UK
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Have you tried the wide flat bearing from a disabled swivel cushion? the sort sold to make entry/egress from cars easier? mine has stainless balls in a plastic spider, 5mm thick, 12" diameter. I believe there's a 10" version too.
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Jc
ATM 10" F6.1, 1/25th wave spec (max wavefront error +/- 1/12.6 in zone 4 of 6, sodium light )
6" F7 spec
127mm F9.4 Refractor
10 x 50 bin
ETX80 (finder)
Canon 20D
PST
DSI 1
and a curious mind
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UKJim
member
Reged: 11/27/07
Posts: 35
Loc: Grantham, Lincs, UK
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Hi All,
Thanks for your kind comments about my page.
For those of you who read it you will realise I was trying to address the concerns of several people, sparked not only by this thread, but also my own research over the last few months from various other sites I had found. It made sense to try and consolidate this Lazy Susan "knowledge" when I wrote up my page.
Bob you said:
Quote:
Just wondering, how many encoder boards did you have to replace due to ruined sensors before you got it right, as I did, By Trial And Error?...LOL! I went through three of them! ....Very Stressful!
There is absolutely no warning, and the sensors are wiped right off of the board by the pressure of the magnetic strip digging into them, as soon as you start to rotate the base! You can't see it or measure it, and it happens faster than a 1000Amp. short!
The first clue is that you no longer have any changing Az readings on you COL, and the COL function no longer works. This is very tricky business Jim, and I don't recommend it unless some sort of protection is provided to the magnetic sensors, such as a raised barrier as I mention in this post.
Well, I've had NO trouble, no damage, and I'm still on the original encoder boards, despite dismantling and re-assembling for maintenance many times, cleaning, Teflon lubrication improvements, and finally the Lazy Susan mods! Sorry!
While I agree that not only you, but several others have complained about the apparent ease with which the sensor chips can be "wiped out", I don't understand how this is possible given that the brass bush is designed to keep the magnetic disc AWAY from the chips .
In the interests of science and helping others can you recall how you might have done the damage?
I gave my thoughts on my page as to why I think folk could cause the damage, but since I've not actually killed them myself I don't "get" what actually does it.
Bent encoder disc? Tightening too much? Adding washers where you shouldn't have? Did you remove the original Teflon pads? Was your Lazy Susan a very slimline style? Did the magnetic disc slip off the brass bush and get skewed when you were re-assembling the base? Did you remove the brass bush altogether!!?
I totally agree with you that Orion should try and protect the chips - your idea of a raised barrier seems a good one. It would be interesting to know exactly what improvements they have made to the Az bearing for the new XX12.
Has anybody else screwed their sensor chips when trying to make mods to the azimuth bearing? If so what went wrong?
Anyway, I hope my page provides sufficient warning and information to help people understand how they might accidentally damage the sensors, so as to prevent them doing so.
Jim
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Orion XT10 Intelliscope with COL.
Low-Profile Crayford+AccuFocus
Orion 25mm, 10mm Plossl EP's
Baader Hyperion 13mm 68deg with 14 & 28mm FTR's
Adler Optik Skarp 38mm(32x)2" 5 EL SWA 70*FOV
Orion Shorty-Plus 3 El. 2xBarlow
Baader Laser Collimator. 13% Moon filter.
Binos: Super Zenith 10x50 7deg FOV, Adler Jupiter 20x80ZCF and Fumoto 10x25
Laptop+Stellarium, Starry Night, ECU.
My site dedicated to the www.Orion-XT10.com
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epee
professor emeritus
Reged: 11/30/06
Posts: 696
Loc: Suh-van-nuh, Jaw-juh
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I did! I did! Early on in my experimenting with the azimuth motion I tried the old CD-ROM as a bearing trick. It seemed perfect in that the center hole of a CD-ROM is just big enough for the brass bearing to slip into. I'm still not sure how the encoder was damaged because the entire disc/bearing/encoder board assembly SHOULD have been shimmed upward the thickness of the CD. All I can imagine is that the CD allowed the brass bearing to wobble enough to scrub the encoder sensors.
The CD-ROM bearing mad should not be used by Intelliscope owners.
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Jim Girardeau
Orion XT12 Intelliscope
Celestron 11X80mm binoculars
Edited by epee (09/16/08 06:22 PM)
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