CurtPalme.com Home Theater Forum

**Curt Palme** · Last edited by Curt Palme on Sun Mar 14, 2010 1:34 am; edited 1 time in total

Kal, maybe add this step into the 'advanced procedure' article.

Guys, I'm sure any of you that have tried taking a tube out of a Marquee LC housing have bitched at how hard the tube is stuck to the aluminum LC housing, and I know I've broken a couple of tubes when trying to get the tube out. The silicone under the front edge of the tube is impossible to get to, and REALLY seals the tube to the housing.

I tried a new step last night based on advice here...

Once you've taken off all the silicone around the sides of the tube (between the tube and frame), and cleaned it out thoroughly, pour gasoline into the groove. I did that yesterday morning after using the claw hammer technique shown in the 'advanced procedures' to loosen the tube. No go, the tube was in there tight.

I let the gas soak for the last 24 hours, and did the claw hammer thing again. The tube started moving right away, and after a few taps, came right off frame. No smashing of the tube.

I immediately flushed the LC assembly to get rid of the gas, in case it attacked the bellows.

I had the tube outside yesterday, and had to top the gas off three times because it evaporated within a few hours.

Thought I'd share this though, it worked great.

<edited because I'm an idiot!>

Mark_A_W · Posted: Sat Mar 13, 2010 11:56 pm Post subject:

Turps, not petrol.

It doesn't evaporate.

**Curt Palme** · Posted: Sun Mar 14, 2010 12:53 am Post subject:

I haven't had as good success with turps as with gas.

Also, I had a bit of a scare today. Once I washed the LC housing, I put it in a (don't laugh!) RONCO food dehydrator to dry it.

I use this dehydrator for 'baking' reel to reel tapes (google that, it's too long to explain), and I figured putting the LC housing in a 120 degree environment (approx) would do a nice job of drying it quickly, as I wanted to silicone the new tube in.

I went back 1/2 hour later, flipped the housing, all was fine. Went back another 1/2 hour, and the damn green C element had fogged up permanently on one 1/2 of it. I thought maybe it was the gas reacting with the plastic, but no, it seems that it's heat related. Looks like the concave C element captured too much heat, and crystalized the C element. Luckily I had a spare.

I ran gas over the C element, let it sit for 5 minutes, washed it off and let it dry (outside of the dehydrator), and the clear side was still clear.

Nashou66 · Posted: Sun Mar 14, 2010 1:04 am Post subject:

Damn, a wasted Green C-Element!! that guy in Chille needs them!!!!

Athanasios

draganm · Joined: 08 Mar 2006 Posts: 5086 Location: Colorado

**Curt Palme** · Posted: Sun Mar 14, 2010 1:32 am Post subject:

Yeah, sorry, Tim called me and gave me crap. It was first thing in the morning when I posted. Smile

What I meant to say was that the front of the tube is siliconed to the metal frame on the front, and it's usually a PITA to break that seal. I'll go edit the orignal post...

CIR Engineering · Posted: Sun Mar 14, 2010 3:06 pm Post subject:

stefuel · Posted: Sun Mar 14, 2010 3:36 pm Post subject:

Gasoline??? WOW, what a great idea. I'll have to remember that one Laughing

**Curt Palme** · Posted: Sun Mar 14, 2010 3:38 pm Post subject:

Remember, it's only to loosen a tube, not to take your frustrations out on your set. Very Happy

draganm · Joined: 08 Mar 2006 Posts: 5086 Location: Colorado

Nashou66 · Posted: Sun Mar 14, 2010 8:19 pm Post subject:

It was Chip who told us about gasoline Wink

.

Thanks Dragan Very Happy

.

If you let the whole assembly soak for a few days the silicone even squeezes out from between the metal face plate and the cooling fins/housing and the tube.
you then can just pop it right off with a little help from a flat flexible knive.

Athanasios

pmscompany · Joined: 24 Apr 2007 Posts: 3

Sparky015 · Posted: Sat Apr 17, 2010 12:27 am Post subject:

Arrrrgh! I didn't do this, and I smashed one of my dud tubes extracting via the claw hammer method. It was a decent tube too. Now I know to use gas for the other two. Green has some burn, but red as barily any, so I'd like to save them. PITA

**Curt Palme** · Posted: Sat Apr 17, 2010 12:38 am Post subject:

Yes, I did that.. twice. Luckily it was on really toasted tubes, so I didn't really care, but try that gas thing, and it should be fine.

Seems like the tubes will not leak the gas into the glycol, so the C elements are safe. I immediately flushed the chamber with water as soon as the tube was out, so the C element on the second tube was fine.

Mark_A_W · Posted: Sat Apr 17, 2010 12:46 am Post subject:

For gods sake take the C elements out first!

Turps is better than petrol - it doesn't evaporate, and it's not quite as nasty.

Sparky015 · Posted: Sat Apr 17, 2010 12:52 am Post subject:

I did that Mark. I bought new C-elements and bellows as well, so I already have them out. It's just the housing and the tube now, and so far the housings are winning. Tomorrow I will work on the the other two. Green I don't so much care about as it's got some wear, but the red barily has any, so I want to be careful with it. Blue barely had any either, and of course that's the one I smash. second tap and POW! Rest assured though, all C-elements and bellows are out of harms way!

Nashou66 · Posted: Sat Apr 17, 2010 2:14 am Post subject:

Paul, remove as many of the parts from the housing leaving only the tube and faceplate. then get a pan or plastic tub that will hold the tube and be able to allow enough petrol to cover the entire aluminum housing. I also helped the gasoline seep its way in between the silicon and aluminum by wedging a very thin knife blade that is the same thickness from tip to end. I cut around the tube glass side and aluminum side. Then I also took a narrow philips screw driver and poked down into the silicon wiggling parallel to the tube to not put pressure on the glass. Then I let it soak for 2-3 days. I then scraped the rest of the silicon out and from the face side you could see the black RTV squeezing out. Here i used the same thin blade and worked my way around the glass and faceplate. eventually i was able to put a wide chisel in between and gently pry all the way around. it is easier when most of the side potting silicon is out. If you have trouble another day in petrol with most of the silicon gone helps. I did four dead tubes this way even though i could have sashed them. I did it to practice for a day i might need to move a good tube.

Athanasios

stefuel · Posted: Sat Apr 17, 2010 10:19 am Post subject:

I have not tried this, but would bet money that it would work. If you had the time and only stripped all the hardware off first, just dip the tube and aluminum housing with all the silicon still on it (fully submerged) in gas and let it soak for a week that it would fall right out. If you doubt that, just put a little gas in a glass jar with a small chunk of fully cured silicon in it and watch it for a week. In a week that nice chunk of silicon will turn into loose snot. So who's up for a experiment? You won't hurt the tube or the aluminum housing. Surely someone here would love to prove me wrong Mr. Green

Nashou66 · Posted: Sat Apr 17, 2010 6:15 pm Post subject:

Sparky015 · Posted: Sat Apr 17, 2010 11:49 pm Post subject:

Well, I have my red and green in containers soaking in gas, so I will let you know. I removed the 4 bolts holding the tube face plate on as well. I figure that silicone will be shot from the gas, and I'll have to redo it. I picked out all of the grey silicone, so it's just the black silicone now. I'm hoping it doesn't take a week, I'm anxious to start building up the projector again!