Removing a SF M6 bezel

[BenjiBot]

Hello, I'm trying to get the stock bezel off my M6 and it won't budge. I'm thinking of popping it in a hot (220º) oven for 4-5 minutes to try to soften the bonding agent, but I'm worried I might damage the head. Are there any plastic pieces inside the head? I would hate to melt an O ring or something, damaging the reflector – this would be a fairly typical kind of outcome for me. Has anyone used the heat method, and if so what should I bear in mind? I am keen to mod this light further

Thanks, in advance

 

[Sgt. LED]

Try it in a pan on top of the stove, bezel down.

Heat and test, heat and test. Don't crank it up very high.

You do have a glass lens right!

Get a mouse pad and some oven mitts. Oh is it the crennelated varety? That makes it simpler!

 

[DaFABRICATA]

If you have access to a small torch or even a heatgun/blow-dryer it will decrease your chances of messing something up.
I use a small torch to heat only the area to be unscrewed.
Heat some, try it...if it still doesn't unscrew, try more heat, but you also need to know when to let it cool and try again later as to not over-heat stuff and melt plastic.

 

[Patriot]

Just be careful if you use a heat gun because they'll melt normal plastics in the blink of an eye if exposed to direct exhaust air. Don't ask me how I know that.

Depending on the generation of M6 head you'll have between 1-3 meltable parts so indirect heat is probably the best bet. The most susceptible parts is the nearly paper thin separation ring which fits behind the bezel and acts as a buffer agaist the glass. Fortunately you'd never be able to get direct heat on it unless the bezel was partially unscrewed already.

If you have a the crenelated or strike bezel removal will be the easiest. If you have an earlier head with recessed, plastic retaining ring removal is going to be a PITA. I've never successfully removed one but member RPM (Richard) recently had to machine one of the rings out which of course destroys it in the process. It didn't matter in his case since he was installing one of his superb Ti bezels in the process.

One final warning if you have an original M6 with plastic lens there's nothing you'll be able to do about it. These are pressed in and then sealed with a clear epoxy of some type. You probably won't have to worry about this unless your M6 below serial# 1000 and all original. It's easy to tell if it's plastic by tapping on it with a finger nail or by the lack of tool recesses just inside the rim of the head. If you have a head like this just put the thing away since they're kind of collectible. You can always pick up another head in the Marketplace or fleebay.

 

[BenjiBot]

Thanks for all your advice. I am trying to replace the stock bezel with one by RPM, and I have the removal tool. But. The. Thing. Wont. Budge. Tried heating it in the oven, but I lack tools to get the thing in my vise when it's hot. So I took it to a work shop where a guy used a number of different wrenches and techniques, but he couldn't get it off either. He didn't have a way of heating it safely, though.

What he did manage to do is jam the head on to the body, which I now can't undo. Sadly my bulb and bi pin were not installed, so I now have an M6 that doesn't work (it's a newer model, by the way, with the crenelated bezel).

:sigh:

Anyone know why SF put such a strong bond (Loctite?) in there?

 

[Sgt. LED]

Dang I'd ask you to send it to me but the postage would eat you up.

I though it was a pretty easy job. Maybe mine had just a little bit of Loctite?

 

[BenjiBot]

Thanks for the offer! We tried a lot of force, was concerned the vise was going to flatten the head as it had to be held in place real tight. Didn't move at all

 

[DaFABRICATA]

:sigh:

Anyone know why SF put such a strong bond (Loctite?) in there?

Oh man, sorry to hear about that!

They put the loc-tite on so you can't open it.
They are not meant to be taken apart..

Worst case senario, you can send it to me along with the tool, and hopefully I can get it open. I have a great track record of being able to open almost any SF head.
I use a piece of wood 2X4 with a hole cut in the middle and cut in half.
Its then placed in a vice to hold the head while I use a small torch to quickly heat the threads. Every head I have done this way has opened except for one.

I know I'm far away and the wait sucks, but I figured I'd offer.

 

[BenjiBot]

Thanks DeFABRICATA, I'm going to try a few local options but I might well take you up on that offer if I can't sort this out in a couple of weeks or so. The light is already looking scuffed up from the vise, don't want to do any more damage to it

 

[LED Zeppelin]

All of the suggestions here are good.

I use a setup similar to Tim (DaFABRICATA). Machined wood blocks in a vise with pressure at the base of the head. Too much clamping force will deform the head and make it more difficult. At first I clamped it hard enough that the RPM bezel tool didn't fit. If this happens the tool will mar the notches of the bezel when it's turned.

My method now is to preheat the head in very hot water. I then place the wet head with some water drops on it in the clamp. Using a propane torch I heat the bezel thread area until the water droplets around the bezel/lens boil. It's ready to remove at that point.

For the early flush plastic bezels I do the same thing. I ground the tips of some large needle nose pliers to fit the tooling notches of the bezel.

 

[BSBG]

Why, again, were you trying to do this with the body on it?


I use the oven method. 210 degrees F (105C) for 5 minutes. This is not hot enough to melt any plastic components but should soften the thread locker. Clamp the RPM tool in your bench vise, grab the head wearing a pair of Mechanix gloves, place it on the tool, press down and twist. Spins off like a mayonnaise jar, at least for me. You could use a strap wrench at this point, being sure to keep downward pressure on the head to engage the tool.

 

[darkzero]

I also normally secure the head when opening SF heads. With the M6 I did it "backwards" like BSBG. I secured RPM's tool in the vise them placed the M6 on top. Applied heat with a butane torch then used Duncan Kitchen Grips to turn the entire head with my body weight holding the head in place. I did two heads in a row at the time with ease.

 

[BenjiBot]

Why, again, were you trying to do this with the body on it?

Tried it every which way. Head in the vise, tool in the vise. The head rotates when it is held in the vise and the wrench applied, and we didn't want to clamp it harder in case we crushed the head. Seeing as the body has all those bumps and grooves we figured it would be worth clamping that to stop the light rotating in the vise. It didn't work.

Seeing as the oven trick didn't work I'm going shopping for a new butane torch :devil:

 

[Patriot]

For the early flush plastic bezels I do the same thing. I ground the tips of some large needle nose pliers to fit the tooling notches of the bezel.

I'll have to try that method LZ.....and just to make sure I'm understanding, you're only using two points of contact right. I'm surprised there is enough bite for that to work but apparently there is.

 

[LED Zeppelin]

I'll have to try that method LZ.....and just to make sure I'm understanding, you're only using two points of contact right. I'm surprised there is enough bite for that to work but apparently there is.

Yep, just the two tips of the pliers. They have to be pretty large pliers to span the head, and I ground my tips to fit the notches.

Enough heat is the key. It seems that there is less loctite on the older heads.

 

[BenjiBot]

A quick update: a box-fresh blowtorch sorted this problem out in no time. 60 seconds circling the stock bezel and it slid right off with minimal fuss. There was loads of grey gunk in the threads, a lot of Loctite.

Thanks for all the suggestions offered, I tried four or five of them with no success but the blowtorch was the ace. Maybe this thread will prove useful to someone struggling with an M6 bezel in the future

 

[roguesw]

I had the old style recessed plastic ring.
I have access to an old electric hot plate.
I put some aluminum foil on the hot plate so that
the bezel was not in direct contact with the hot plate.
Dialed it up to about 3/4, heated it through for about 4-5 minutes
checking every so often by using an X-acto knife to pick at the
loctite that was on the surface.
The moment the loctite was soft.
I put a rubber strap clamp on it, used the long nose needle plier.
method and the plastic ring unscrewed with no effort.
The needle nose pliers I used was the ones used for jewelry, it had
no teeth on it, and i found the profile fitted the notches perfectly.

Mine had so much loctite that it filled the gap between
the plastic ring and the head.

The aluminum head expanded more than the plastic retaining ring
so when it was up to temperature, it was easy to unscrew.

Now its got a nice shiny RPM bezel on, .
Thanks for all the advice on this thread. really helpful.

Des