HELP! McModule stuck in PM6!

[Lucien]

This is the second McModule I'm putting together for my PM6. The first one I did, I screwed in the module to the body, then epoxied the emitter on so that I could center it with the reflector in place. For that one, the module was somewhat rough going in - so I broke it in by screwing it in a little, then screwing it out, then screwing it in again a litte further, then out again... Repeating untill the module would go in all the way, and cleaning off any grit on the threads as I went.

I just started work on a second module the same way, but getting to the halfway point, the module hit a block. Trying to screw it out, I found that I could shift it a little and thats it. Now I can rotate it about 5-10 deg in either direction, but only with a lot of effort and no further.

I placed the body and McModule in my freezer for half an hour, hoping I could get the McModule to contract a little so it'd come out but no luck. /ubbthreads/images/graemlins/frown.gif

Has anyone encountered a problem like this before? If I can't get the module out, then this PM6 is going to be a write off... /ubbthreads/images/graemlins/mecry.gif (And its the only one I have too!)

 

[mahoney]

I would suggest some penetrating oil, Kroil brand is my favorite. Remove the switch/tailcap and try to keep it off the emitter and electronics. Give the oil at least a few minutes to "work" before trying to loosen the module. Some well fitted wooden clamping blocks for the light body and McModule might help too.

 

[cy]

See this thread
link

 

[Lucien]

Thanks guys. I tried using some sewing machine oil - its pretty much the only lube I can find in the stores - but no luck. That thing is still stuck, and I've used quite a bit of oil too...

The only good thing is that I haven't added anything to the module yet, no LS and no electronics. Its just the bare McModule.

Again, HELP! /ubbthreads/images/graemlins/help.gif

 

[kakster]

If theres no electronics on it, try baking it in the oven. It might make the metal expand enough to loosen it off.

 

[mahoney]

Sewing machine oil is pretty thick compared to penetrating oil. Try a much lighter petroleum product like lighter fluid, naptha, gasoline, paint thinner... Be carefull not to blow yourself up, not to mention these may damage the finish and o-rings.

The heat/cold method works best when you make the outer object hot while keeping the inner object cool. If you can get some version of "spray freeze" you could heat the light and then cool just the McModule. Work fast, the heat will equalize quickly in aluminium.

I suggest drilling an appropriate hole in a wood block, cutting the block in half and clamping the light in a vise between the blocks. This should allow you good torque without distorting the light. File some flats on the McModule so you can use a wrench.

Worst case senario, the McModule is cheaper to replace than the light, cut off the top of the McModule or drill through the top and grind a hacksaw blade to fit in the hole. Cut through the McModule side just down to the threads of the light in a few places and you should be able to break out the pieces.

Good Luck

 

[unnerv]

you can also try some aluminum tapping fluid like tap magic. It works wonders for gaulled aluminum. You can usually find it at your local hardware store like homedepot or orchard. I had one that was gaulled up and wood blocks in the vice with some tapping fluid got it out. Once out use a sharp dental pick or exacto knife to clean out the swarf that maybe stuck in the treads.

 

[Lucien]

Thanks, I don't actually have access to tapping fluid over here, or at least I haven't found anyplace that stocks anything like that. The oil I used does get into the threads... enough that it flowed all the way though and coated the inside of the battery tube. That 5-10 degrees of travel is smooth, but it still won't come out. /ubbthreads/images/graemlins/frown.gif

I'd already thought of cutting the top off the McModule, and using a Dremel or needle files to wear down the remaining bit to break it out. I haven't done it yet as I was hoping I could save it, but...

Won't have time to do that till Monday, hopefully another solution will pop up before then.

And the shop seems to be out of stock of McModules. /ubbthreads/images/graemlins/icon23.gif

 

[Matsan]

Hello
I have never have the trouble you are in,but did you try the tools like this? strap wrench
You should use two wrenchs,one put on module and another on body.
You may find out cheeper tolls like this in local hardwear store.

 

[Lucien]

Hi Matsan,

Sadly I can't even find that in my local shops. /ubbthreads/images/graemlins/frown.gif Also I was worried that if I tried to use extra force to unscrew the module, I'd really damage the threads.


Well, I finally got the module out today - in peices. Sawed the top half off just above the threads with a mini hacksaw, then used a Dremel with a high speed cutter to make three slots in the inside of the module at the 12, 1 and 6 o'clock positions. I left a thin bit of metal remaining, had to be careful not to overcut and damage the threads. Then used a pair of pliers to break in the smallest section - the rest was easy.

No significant damage to the PM6 threads that I could see. Oddly enough, after cleaing up the threads I tried my other module and it went in and out really easy... /ubbthreads/images/graemlins/icon3.gif