Repairing DTS400, how to remove counter weight?

[niallsmart]

Hey folks,

I'm attempting a repair on an out of warranty RTS400. This is not my first repair rodeo, but I've been stymied by removal of the brass counter weight (aka "cam").  From the parts diagram, it appears to be secured to the spindle with an M4 bolt (part #32).

There are two indentations in the cam, which presumably receive a special tool used to hold it still while removing the screw. I'm using a large needle nose pliers for this purpose. However when I turn the screw counter-clockwise, the armature/shaft actually turns as well, so the screw doesn't actually loosen. I am having to apply a large turning force for the screw head to move, so my guess is that the red thread locker applied at the factory is stronger than the friction between the brass cam and the spindle.

Would appreciate any tips from folks who have experience disassembling this tool. Perhaps I'm going about this the wrong way entirely, or there's some way of locking the spindle. I've attached two photos which might be helpful...

Thanks,
Niall

 

[Ron B]

Having spent most of my life in heavy manufacturing, I am going to tell you what you do not want to hear.
I can tell you that even though there are numerous types of loctite, the standard rule is that red is permanent and blue can be disassembled.  The red can be broken, it just takes a lot of force.  Heat helps to break it, but don't see how you could use heat.  I never used red on fine threads, don't know if the threads will give before the loctite.

 

[niallsmart]

I decided to hold the spindle by unceremoniously jamming a screwdriver into the blades of the cooling fan. The screw loosened without as much force as I expected, and the fan survived unscathed. After removing the cam and some other intermediate parts the armature/fan/plate/bearing came out as one assembly (see attached photo).

Another option I considered was grinding a slot into the top of the spindle and hold from that end using a screwdriver, but that would be a rough cut with a Dremel and I didn't want to throw the balance off.  An extra small Knipex might be able to get enough of a grip on it, but I only have a larger one.

Surprised there isn't an obvious way of doing this. Wonder what they do at the factory.

 

[squall_line]

My guess would be that they have a tool that looks similar to the tools that are used on an angle grinder or brake caliper, essentially a fork with pins and clearance for the driver.