CurtPalme.com Home Theater Forum

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

I had a focusboard with serious damage on the connector (see pictures) and there where two more focusboards missing. So the former owner of my projectors had a mysterious focusboards problem. I have to add that it seems all parts on the focusboard are still ok only the connector is burned.

I found the case that did this and took it apart. It seems there is a trail of glycol from the tube to the focusboard connector. It is still wet. Case solved?

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

By the way I had this one in my blend. Glad I found out!

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

There is indeed some moisture on the bottom of the blue tube. Seems to come from the ring, not the c-element.

**Curt Palme** · Posted: Tue Nov 17, 2015 5:15 pm Post subject:

That would definitely be my guess. I had a BG808s retro that was taken out the same way, leaking glycol that dripped down into the 96 pin connector. One night, right at the end of a show, I had a big BANG!, and a similar hole burnt into the convergence board.

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

Wow. Case solved than. Did not know such a very small leak had such big consequences. Reminds me of that space shuttle that went down because of a leaking o-ring. Might be the o-ring here.

**Curt Palme** · Posted: Tue Nov 17, 2015 7:34 pm Post subject:

It's very rare for barco tubes to leak. I've had one.. no, two actually due to excessive pressure, but the bellows generally are excellent.

Tom.W · Joined: 09 Mar 2006 Posts: 6635

**Curt Palme** · Posted: Tue Nov 17, 2015 9:26 pm Post subject:

The other 4 are for the lenses.

Tom.W · Joined: 09 Mar 2006 Posts: 6635

Tom.W · Joined: 09 Mar 2006 Posts: 6635

**Curt Palme** · Posted: Wed Nov 18, 2015 5:27 pm Post subject:

Ah sorry!

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

**Curt Palme** · Posted: Wed Nov 18, 2015 5:49 pm Post subject:

I definitely leave an air bubble inside, but when filling through the C element, it's hard NOT to.

I have seen glycol shoot out of the fill screws, just like a Marquee, in fact one last week that came out of a planetarium projector with 30K + hours on it. almost hit me in the face. Very Happy

Tom.W · Joined: 09 Mar 2006 Posts: 6635

This 1209 c element guide says to not leave air bubbles due to internal reflections.

http://www.curtpalme.com/Changing_C_Elements_Barco5.shtm

You would think the rubber bellows allow for enough expansion. Curt do they ship new from the factory with air bubbles ?

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

There are no visible bubles in the tubes I have. Also after replacing glycol I take care the visible bubles are gone. Made me spill some glycol.

**Curt Palme** · Posted: Wed Nov 18, 2015 11:18 pm Post subject:

tschaeikaei · Joined: 08 Apr 2013 Posts: 490 Location: Germany/Saarland

Seems all C-element holding rings and housings are the same.
I am using tubes out of an 1209s (with Scheimpflug) that look exactly the same as yours.
In the 1209s, the lens screws are bolted into the outer aluminium mask.
And thank you for the pics, i discovered a mistake i made when i put the 1209s tubes into the Marquee.
I thought the same as Curt did first.
So my lenses bolt to the C-element holding ring. Need to make some spacers for this.

For air bubbles and stuff: wouldn't this make sense?
- Take the glycol out.
- tighten the four spring loaded screws, each two turns
- fill in new glycol, try to do it without any air bubbles left in there
- mount the black c-element holder ring and its four countersunk bolts
- loosen the long springloaded screws again by 2 turns each

You'll end up with no air inside the chamber, but with enough possibility to expand the glycol.

To fill Barco tubes without any air bubbles, i struggled hard until i discovered this:
You normally do this with the tube face completely horizontal.
Do it that way, insert the C-element and before pressing it to the o- ring,
take a piece of wire and just lay it on the o-ring, so the c-element does not seal completely.
Press the C-element on it with little force (I used a weight about 2kg on it)
and make sure the area where the wire sticks out is minimal higher than the rest.
so the air bubbles can collect in the wire area and escape slowly.

Than you can pull out the wire, press the c-element down and simultaneously place the black holding ring
and its four screws. After tightening them, there should be no or very little air in there.

Regards, Julian

thewolfman · Joined: 28 Mar 2011 Posts: 1311 Location: Sweden

A little of topic perhaps but it's always useful to know as much possible.

https://www.youtube.com/watch?v=DJfSyYuKMRw

Nashou66 · Joined: 12 Jan 2007 Posts: 16171 Location: West Seneca NY

redfox001 · Joined: 16 Mar 2009 Posts: 2257 Location: The Netherlands

I still have that tube under investigation on my attic. Nice and dry. I removed some preasure but might have to replace an o-ring. I think I keep it for myself as spare. I would not dare to sell it to someone getting potential glycol problems in the future. On my blend I will occasionally check it. Wear is very close to zero.