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Equipment Discussions >> Mounts

Pages: 1
MHamburg
scholastic sledgehammer
*****

Reged: 06/21/06

Loc: Brooklyn, NY/Berkshires, MA
Really Stumped! new
      #5441302 - 09/26/12 09:40 AM

I never anticipated such a simple but insurmountable problem when I began hypertuning my cgem yesterday. I cannot loosen the counterweight bar locking retaining nut at the base of the dec axis. Believe me I tried everything from a 24" pipe wrench to heating with a propane torch. Has anyone else ever run into this stupid problem? It looks like I will be forced to bring the mount to a machinist to try to free the nut. I thought I was going to save some money by doing this with Ed's kit, but . . . . even Ed Thomas is stumped and has gone quiet.
Michael


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RTLR 12
Post Laureate
*****

Reged: 12/04/08

Loc: The Great Pacific NorthWest
Re: Really Stumped! new [Re: MHamburg]
      #5441307 - 09/26/12 09:45 AM

Sorry, Michael. As a professional Master Automotive technician with over 40 years of experience all I can tell you is "Righty Tighty...Lefty loosey.

Stan


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simpleisbetter
Carpal Tunnel
*****

Reged: 04/18/11

Re: Really Stumped! new [Re: RTLR 12]
      #5441329 - 09/26/12 09:55 AM

Have you tried spraying it down well with WD-40 and letting it set and soak in for a while?

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MHamburg
scholastic sledgehammer
*****

Reged: 06/21/06

Loc: Brooklyn, NY/Berkshires, MA
Re: Really Stumped! new [Re: simpleisbetter]
      #5441348 - 09/26/12 10:04 AM

WD 40 and Liquid Wrench!!
Michael


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Lee Jay
Pooh-Bah
*****

Reged: 02/27/08

Loc: Westminster, CO
Re: Really Stumped! new [Re: MHamburg]
      #5441523 - 09/26/12 11:54 AM

Liquid wrench + 24 hour soak + big cheater bar.

I don't know what this looks like, so I'm not sure how much torque you could rationally put on it before you break something.


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Midnight Dan
Postmaster
*****

Reged: 01/23/08

Loc: Hilton, NY, Yellow Zone (Bortl...
Re: Really Stumped! new [Re: Lee Jay]
      #5441631 - 09/26/12 01:08 PM

WD40 is not thin enough to penetrate in a situation like this. Liquid Wrench is better. Best is Kroil, but you can't usually find that at your local hardware store.

Squirt the Liquid Wrench around the nut where it makes contact with the threads. Give it 24 hours to soak into the crevices. Giving it an extra squirt now and then helps.

Then I would fill a container with ice water and orient the mount so that the end of the counterweight bar is in the ice water. Let it sit for an hour to cool. Now heat the nut with the propane torch. The cold should cause the bar to shrink slightly and the heat should cause the nut to expand slightly. That's your best bet for getting off. Just be sure you don't heat the nut for too long or you'll just heat up the bar too. Try to direct the heat ONLY at the nut if possible.

-Dan


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*skyguy*
Carpal Tunnel
*****

Reged: 12/31/08

Loc: Western New York
Re: Really Stumped! new [Re: MHamburg]
      #5441912 - 09/26/12 03:39 PM

I'm not familiar with this mount ... however, I've done my share of rebuilding other GEMs. This is probably not the problem ... but, have you made sure there is isn't a small set screw holding the nut in place? I've missed them before when disassembling a mount.

Good Luck!


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Stew57
Carpal Tunnel
*****

Reged: 05/03/09

Loc: Silsbee Texas
Re: Really Stumped! new [Re: *skyguy*]
      #5441927 - 09/26/12 03:47 PM

AeroKroil is the best penetrating oil. Dry Ice will cool the shaft well. A high heat heat gun will work on the nut with less chance of burning paint. Even if the shaft heats some, the nut will expand, the shaft will expand, and the space between them will expand. Yes you can expand nothing!

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Starhawk
Space Ranger
*****

Reged: 09/16/08

Loc: Tucson, Arizona
Re: Really Stumped! new [Re: Stew57]
      #5442138 - 09/26/12 06:04 PM

Are you sure you can't just unscrew the weight rod? Try that, first.

-Rich


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MHamburg
scholastic sledgehammer
*****

Reged: 06/21/06

Loc: Brooklyn, NY/Berkshires, MA
Re: Really Stumped! new [Re: Starhawk]
      #5442268 - 09/26/12 07:43 PM


Thanks for all the tips. Believe me but none of the above worked. The machinist who made my custom pier plate is going to help me out. And I thought I was going to be clever and save some money. . .Hah! I'll let you know what happens.
Michael


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cclark
member


Reged: 07/29/08

Re: Really Stumped! new [Re: MHamburg]
      #5442575 - 09/26/12 10:29 PM

I had the same problem when first taking mine apart.

I think this suggestion (below) is in Ed's video, but the one thing I needed to do to get it to work was to use a 2mm allen wrench to get enough leverage.

Remove the two set screws completely (accessible from the hole in the back side of the housing right behind where the nut is). I think they are 1.5mm hex. Then slide a 2mm allen wrench in the hole from the back and put the end in where one of the set screws was previously. While holding the allen wrench, grab the top of the dec assembly (where the saddle plate was) and turn the dec shaft (but make sure the clutch is loose - you don't want to be turning against the gears). The allen wrench will act like a pry bar (sort of) and keep the nut from moving. You may be able to break it free - but - be careful to keep an eye on the allen wrench to make sure it does not bend (or break). It will flex a little but it may provide enough strength to break the nut loose.

I had a bear of a time getting mine free, but I was finally able to get it off using this technique.

Just one other tip I have from when I did mine. When putting the large bearings back in the ring gears - don't force them. Keep trying to reseat them until they slide in - they eventually will. I was sweating bullets thinking I was not going to get them back in, but after about 20 min of seat-stick-remove-reseat, they finally slid right in. It is a really tight fit, but I promise they will go back in smoothly - just keep at it. Once you get the hang of it they are really pretty easy.


Chris


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EFT
Vendor - Deep Space Products
*****

Reged: 05/07/07

Loc: Phoenix, AZ
Re: Really Stumped! new [Re: cclark]
      #5443260 - 09/27/12 10:37 AM

Michael,

Reading your first post, it just occurred to me that I hope we are talking about the same thing. In your e-mails you have said "counterwieght bar locking nut" which is the large piece of aluminum that the counterwieght bar threads into. However, in your post you called it the "counterweight bar locking retaining nut" and I'm not sure we are referring to the same thing now. If you are talking about the small black metal ring that holds the axis together and is recessed into the housing, that is held in by two small set screws that must be accessed through the hole on the underside of the housing.

Are we talking about the same thing?


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MHamburg
scholastic sledgehammer
*****

Reged: 06/21/06

Loc: Brooklyn, NY/Berkshires, MA
Re: Really Stumped! new [Re: cclark]
      #5443333 - 09/27/12 11:29 AM

Chris,
I finally located the 2 set screws!! (Thanks.) However, no amount of coaxing freed the nut. I did manage to bend the 2mm allen wrench, though. Also, I'm not sure what happened to these screws as I wasn't able to actually back them out. I'm wondering if they are floating around somewhere in the housing (although I didn't hear any rattling.) Michael


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RTLR 12
Post Laureate
*****

Reged: 12/04/08

Loc: The Great Pacific NorthWest
Re: Really Stumped! new [Re: MHamburg]
      #5444240 - 09/27/12 09:11 PM

Are your 2 set screws 180º apart or are they 120º apart?

My mount had 3 set screws for that nut.

Stan


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EFT
Vendor - Deep Space Products
*****

Reged: 05/07/07

Loc: Phoenix, AZ
Re: Really Stumped! new [Re: RTLR 12]
      #5444326 - 09/27/12 09:59 PM

I have never seen one with 3 set screws, but that is not his problem anyways. From posts in the Yahoo group, it appears that his counter wieght bar is actually stuck in the mount along with the counter wieght bar nut. Other than the set screws, he can't even get to the axis locking ring with the set screws.

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BigC
Carpal Tunnel
*****

Reged: 09/29/10

Loc: SE Indiana
Re: Really Stumped! new [Re: RTLR 12]
      #5444397 - 09/27/12 10:40 PM

Quote:

Sorry, Michael. As a professional Master Automotive technician with over 40 years of experience all I can tell you is "Righty Tighty...Lefty loosey.

Stan



As an owner of old Dodges and a former tire installer(about 4000 ) I can tell you there ARE exceptions to that rule. Dodge/Chrysler used to use Left-handed threads on one side of the car;many a wheel needed new studs because some airwrench jockey didn't look or know what the stamped "L" meant!


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MHamburg
scholastic sledgehammer
*****

Reged: 06/21/06

Loc: Brooklyn, NY/Berkshires, MA
Re: Really Stumped! new [Re: EFT]
      #5445193 - 09/28/12 12:53 PM

Ed,
In case I need to replace the cw bar, where is it available as I cannot find it anywhere and don't want to shell out $139 for the ADM upgrade?
Michael


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EFT
Vendor - Deep Space Products
*****

Reged: 05/07/07

Loc: Phoenix, AZ
Re: Really Stumped! new [Re: MHamburg]
      #5445256 - 09/28/12 01:39 PM

The counterwieght bar is the same on on the CG-5 and those can normally be found used. That's the best bet other than ADM.

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Geo.
Carpal Tunnel
*****

Reged: 10/01/08

Loc: Upstate NY
Re: Really Stumped! [Re: EFT]
      #5452382 - 10/02/12 06:03 PM

Take as much plastic off it as you can and toss it in the oven for 30 minutes at 250. Alloy expands faster than steel.

When it comes out rap the nut a bit with a mallet then get a strap wrench on it. IT IS a right hand thread. Oh, and don't use the wife's best oven mitts


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