CurtPalme.com Home Theater Forum

[ronaldus]

Hi everybody,

It's me again,

Since a few months I have some stuff inside my LC chambers. I don't think it's fungus but crystals.

It started with the blue tube first (with one big "snowflake") and then a little bit in the green. Red seems to be OK

In the blue one it seems to float in the liquid but in the green one it seems to be on the C element.

I didn't paint the aluminum and have normal filling screws. Unfortunaltly I discovered after having used silicon RTV kit that it was not needed ('')

I cleaned the new (nashou)bellows with water only before mounting them.
In this thread there are pictures of my tube assemblies with the bellows removed.
http://www.curtpalme.com/forum/viewtopic.php?p=284769&highlight=#284769

There where no scratches on the aluminum and the only blank spot i covered with RTV kit

The glycol is in there since one and a half year. Would cleaning and filtering be enough or do i really have to take off the bellows and paint the aluminium?

Would rinsing with demineralised water and then with alcohol be a good start?

I have one can of tech spray TV coolant left but that's not enough could i filter the old one and reuse it?

If i have to paint it would be nice if people from europe reply what they used because it would be easier to find the products here in France or Switzerland.

I guess I was not careful enough when i did all the cleaning and mounting of the bellows! What a pitty.

I've attached some pictures of my tubes.

regards,

Ron.

[dturco]

No you can't use the old glycol, its contaminated and any microscopic residue in the glycol, or on the chambers, or bellows, will allow for this reaction again.

I had the same issue when I took my 9500 apart to re-tube. I had put the bellows on and used the Techspray CRT Coolant too. Then I used Orison Iceclear and VHT Epoxy paint and still had those crystals and some fungus like what you had in your first post.

I have put it all back together now after a complete scrub down with alcohol. I scrubbed down everything the bellows, the chambers, the tube faces, the C-element, [ well this I wiped] and put in stainless steel fill screws, and flushed the fill hole screws too. That was two months ago. No crystals or fungus as of now.

It seems many that put in Apple Bellows are having this issue about a year and a half to two years later. Since we all bought them around the same time, we may have also bought the Techspary coolant at the same time. Maybe the Coolant was a bad batch, or we just failed to truly decontaminate the chambers or bellows when assembling, who knows?

Try again with "clean room" tactics.

My thoughts are that the release agent on the bellows is the culprit. The bellows need to be scrubbed cleaned, not just wiped clean. That's what I did on this last assembly.

As a footnote, I am not saying the Apple bellows are at fault, or bad, or anything negative, the were new to the scene and we just haven't figured out what, if anything related to them, or during their install is causing these issues.




Edit: The bellows were put on my old tubes first, the fungus and crystals grew. The I put the bellows on my new tubes and fungus and crystals grew there too. This last assembly is still too fresh to know for sure. I edited in case that part was ambiguous.

[draganm]

I think the crystal are dissolved Aluminum, but who knows. In the pictures it looks like it's coming right off the Alum. part.
If you shake the tube the crystal will dissolve and just make the fluid cloudy, so it's all the same stuff, not 2 different things.

[stridsvognen]

Its looks just like my 9500LC, and i'm quite sure its fungus.
My projector have never had new glycol or new belows.

[mc86]

Guys -

I think all fungi are bigger than 1.0um (micrometer). So use of 0.25um filters should get all bugs and even many metal oxide contaminants that might be in the supplied glycol. Rather than cleaning, fungiciding, and putting new "clean" stuff back in again only to risk the same problem, I might recommend use carbon filtration and ultra filtration when filling your bellows. These are about ~$10/ea and are what I am talking about. One should have the capacity to filter "clean" glycol for 3 bellows. To do the carbon treatment would require a pre-filter step, but no biggie.

You get a 60mL syringe with leur fitting, some particular prefilters, a handful of granulated activated carbon (I have 20L pails of the stuff, you could cut open a brita filter), and a sterile ultra filter...that is it.

I've been treating the glycols from a bunch of 7"sony tubes this week to try and study the dye performance and it is easy. when I finally refill, I'm also adding a little fungicide - I'll just need to test their UV/VIS transmittance first to be sure there are no problems.

thoughts?
Matt

[Nashou66]

I haven't had any issues with the few I changed. Clean the bellows well and make sure the ALUMINUM IS NOT EXPOSED ANYWHERE IN THE CHAMBER!!!! One square millimeter of exposed aluminum will cause a reaction.

I recommend painting all housings with epoxy paint....even if they look fine.

Athanasios

[zGman]

Crystals is what I have also - out of 15 9" tubes I mounted last summer,
10 were Marquee and 5 were Barco 1209S. All were processed the same
way with the same materials and used the same techspray glycol.

All of the housings were is good shape and I did not use any abrasives
to clean the housings. None of the Barco tubes have any issues.

Four of the Marquee tubes have no issues. Six of the Marquee tubes
have those darn crystals. All six were built with the new apple bellows.

All the housings have stainless hardware. Everything else was exactly the same.

I am wondering why - is there possibly something leached from the rubber
that forms the crystals? Again - these were good 'like new' housings, no
dings in the coating and no corrosion at all.

I am going to have to dis-assemble and clean and flush all these housings
and fill with new glycol and hope for the best.

Naturally I find this to be frustrating.

G

[mc86]

Ah - I see. I re-read the OP note and as per Drags notes, these are salts and not fungus -- my bad. That leaves us with four choices:

1) The glycol itself has impurities which are coming out. This can be ruled out very unlikely as zGmann used the same batch of materials on multiple machines and only some have failed.

2) The glycol and some exposed aluminum are reacting. ZGmann's experience would seem to rule this out. The OP also seems to be aware of being very fastidious on covering any bare Al.

3) The rubber itself is leaching salts, as proposed. This seems a little more likely. I recall reading on zinc leaching in areas where the popular rubber granules are used for football fields. Zinc is often added to help sulfur vulcanize the rubber. Rubbers are known to "bloom" (that is, salts/impurities migrate to surface - same thing, worse, happens if in solutions in which rubber "swells")...this could explain how zinc salts might get into glycol. If so, I'm wondering if adding a touch of water to the glycol would help dissolve any salts that might be present and keep them from precipitating out. If so, try squeezing out ~15mL of glycol out and squirting in 10mL of pure, non-contaminated with fungus/bacteria (ie, 0.25um filtered) water and see if the salts go away. I'm guessing they are water soluble...

As to why some would fail in this way and others might not, it could be that sequence matters. I have personal experience with glycerol on this. 100% glycerine is EXTREMELY hygroscopic. Open a bottle of pure glycerol and leave it on the table overnight...the next day it will be ~20% water! In 1912 it was shown pure glycerol will be about 80% glycerol when in equilibrium with average moisture-content air and this can happen overnight. Within an hour more than a few % can go into the water. [Kailan, Anton. "Specific Gravity and the Hygroscopicity of Glycerol”. © 1912: Zeitschrift fuer Analytische Chemie, Vol. 51, Pages 81-101.] Ethylene Glycol is the also very hygroscopic, having equilibrium water content with air around 10-15% water.

My theory is this: the bellows filled first have no water and thus precipitate any salts leached from the rubber as they cannot dissolve. The bellows filled last are filled with glycol that is not-fresh and has significant amount of water in it from the atmosphere and therefore CAN dissolve the salts coming out of the rubber.

Finally, am I to understand some of these have painted coatings and some are anodized? If so, there is another possibility that gZmann's data imply:

4) The glycol and the aluminum's anodizing layer are reacting. zGmann's experience makes me wonder. The Barco's are all fine but a significant % of his Marquees are not fine. One explanation would be marquees might have a surface seal and the barco's don't. That is, I know Nickel salts are sometimes used to seal anodized aluminum...perhaps such a sealant layer sometimes reacts? Alternatively, perhaps the anodizing techniques are different, with barco using a hard, non-porous method and the marquees having a porous anodization. Is there more data for barco's using the apple rubber bellows to support the type-of-anodized or coating might matter?


Just some thoughts!
Matt

[dturco]

Great thoughts Matt, here are additional variables, as I posted above. The first time I used the bellows I used no paint and Techspray coolant, like most others have. The second time I painted the surface with the VHT Paint http://www.globalindustrial.com/p/janitorial-maintenance/paint/aerosol/vht-epoxy-all-weather-paint-satin-black-11-oz-aerosol?utm_source=pricegr&utm_medium=shp&utm_campaign=Aerosol-Paint-pricegr&infoParam.campaignId=WU

and used a vegetable based coolant Orison Iceclear http://www.orisonmarketing.com/deicers/AF/antifreeze.html

And in all instances had some crystals and a slimy coating on the tube face glass.

Both times I washed the bellows with bottled water, then cleaned the tube faces with eyeglass cleaner, and cleaned the C-element with eyeglass cleaner. I assembled everything without RTV silicone every time. The first time I used a syringe to fill the tubes through the fill holes. The second time I filled the bellows by pouring the Iceclear directly into the bellow/chambers while holding the tube upright, then setting the C-element into place.

This last assembly was washed with dish washing liquid, then wiped down with alcohol after being left to dry overnight. I then took the Iceclear from a sealed container,filled a measuring cup with 22oz of fluid, re-sealed the container, used a syringe to fill the tubes through the fill holes. Then repeated for the other two tubes. I have no results for the last assembly yet it is only 2 weeks old in one tube and 2 months old in the earliest tube.

But the prior two times the only variable is the bellows, and C-elements, I even used different L/C Chambers on the new and old tubes.

So as you can see different ways of filling have been used. Different types of cleaner has been used, different chambers have been used, and coatings have been used .

All I can do now is wait for time to pass on the last assembly to see what else if anything has happened.

Did I miss anything?

Your thoughts?

[Nashou66]

I just looked at the 9500LC i have that is stock. That has floaties as well. The 9500LC i re did locally had fungus/crystals in all tubes with the blue the worst . All housings had the anodizing gone. So what I think is happening is that over time even the anodizing is breaking down from the glycol or possibly the glycerine. Matt would have to confirm if either of those two will break down Anodizing over time. I have not heard from Greg about any change in his chambers so I assume all is well.

I'll shoot him an e-mail to find out. I too used the tech spray glycol and still have 8 bottles.

My painted housing is starting to show growth near the fill hole locations and on the edges where the bellow meets the face plate.
So glycol must be reacting with the exposed aluminum that is in the fill holes and possibly the gasket screw holes.

I'll do an experiment and put a bellow in a clear bowl of tech spray glycol and see what happened over time.

Athanasios

[stridsvognen]

please keep us updated.

May i suggest someone to put a big stainless screw in the fill hole, like M10 coil/screw, and then drill it out and put a M6 stainless plug in it, maybe do so the head is in the inside of the chamber, so its possible to coat all around it with epoxy. Then i think it should be possible to eliminate all contact with the alu housing.

It will be a while before i'm ready to take mine apart.. Prefer someone else do all the experimenting..

[zGman]

There are more data points to indicate this is an issue with the apple bellows.

I have rebuilt at least 15 marquee housings (with vdc bellows) previous
to last summer's large batch. I have a friend who has done at least 100,
all with no issues. Many PJ's in service for many years and no issues.

So I question the concept that this is due to the exposed aluminum, or
it would occur in every marquee that has ever been built or rebuilt.

It seems to take about 4 or 5 months to show up & I don't want to change
my glycol every 4 months. I am hoping that whatever is leaching out of
the rubber will be depleted and the next fresh fill will last a long time.

I am willing to send a sample of the glycol for testing, and I will try
adding some distilled water to one of the tubes to see if the crystals
will resorb. That is a very interesting concept.

G

[stridsvognen]

[Nashou66]

Well we know for sure that the exposed aluminum is one cause.

So its either the release agent or the material in the rubber . I do remember that Dale at Apple said that his chemist said the material was
compatible with the sample I sent them of Glycol.

Galen, I wonder if BlackStone laboratories would do an analysts? I send my Motor Oil there for testing.

I should ask them and see if they can test the Glycol for what is in it now. They have test kits you can ask for.
But they might be oil only testing facility.

Athanasios

[Nashou66]

Kurt, maybe try letting the new bellows I sent you sit in water for a few days or weeks before installing. Maybe the release agent has permeated into the rubber while sitting in the heavy plastic Bags they ship them to me in. The Smell they give off when I first open them is awful.

Athanasios

[stridsvognen]

[stridsvognen]

Just cleaned one. used concentrated sulfo ( or whatever you call that soap you use to wash dishes) with no water, like when i clean nicotine of a old amp. rub it good, and flush it with 50-60C hot water. Now it got the right rubber feeling, i'm sure the water got dirty, the sulfo is red, and the water in the white bucket got a little brown.

So might be a good idea putting them in sulfo water for some days like you suggested.

[mc86]

Guys -

I proposed we all adopt a generic term so we stop saying "glycol" when it very often isn't ethylene/propylene glycol. How about Optical Fluid [OF] so as to be applicable to both AC and LC CRTs...?

I think there are four distinct things we need to separate as occurrences. We can propose fact-based experiments and apply objective data analysis to understand mechanistic causes. If I were a research director of this, off-hand I'd have five areas of inquiry:

1) Fungus
Has anyone ever verified that the "fungus" IS fungus under a microscope using a hemocytometer, etc? I agree about the splotchy, slimy look of "fungused" tubes seems like that, but how do we know?
Has anyone ever filtered for fungi and/or mixed in fungicides with their OF?

2) Slime
Most likely not all slime is fungus. I wonder if OFs have (techspray and IceClear and others) have silicates in them? The article on EG I linked to above points out many anti-freeze compounds have silicates in them -- and silicates gel or "get slimy" over-time. Silicates are just an inexpensive metal corrosion inhibitor. If I read-up, I could figure out how to test them for silicates in my lab. Anyone ever get slime using 100% EG purchased from a chemical supplier like Fisher/AVR/Sigma? Here's a very broad, not-bad AF overview.

3) Corrosion of metals
Bare, anodized, and coated/painted metals. I know heat degrades EG, EG and the degradation acids produced can attack anodized surfaces and bare metals. I can't say factually about glycerol corrosivity with certainty/literature. The rates and specifics I don't know. There are handbooks on corrosion in my engineering library and online I'd need to consult, etc.

4) Leaching from the rubber
One solution might be to soak the apple rubber bellows and a VDC belows in warm water, warm OFs, and warm water+OFs for a week or so (I have constant temp baths). For water, I could do this starting with a very sensitive conductivity meter in DI water and we'd have some factual data! For OFs, I'd likely cool and look for precipitates + do chemical analysis if they occur. I could also surface rinse with organic solvents and analyze oils/residues.

5) Optical Fluid and Fluid Property database
A collection of materials...

Dave - The "vegetable-based" IceClearAF is just glycerol and water +1% of their own proprietary anti-corrosion product as per the MSDS on their website. I'm guessing they refine glycerol that is sourced as a bi-product of biodiesel production...if the biodiesel comes from SVO they can make the claim! I found MSDSs on other sites that said it was potassium acetate (a simple salt), but presume Orison's own MSDS is correct...

I'll need to write-up detailed instructions and a submission form, but I would be happy for folks to send me their OF samples. I run a teaching chemical/biochemical engineering teaching lab and have many of the analytic and classification tools needed. I can do much of the analysis and we can all figure out what is going on. Geez, I may need to setup a Sharepoint sub-site for this...

cheers,
Matt

[Nashou66]

Ok ignorance showing here... What is Sulfo Water? Sulfuric Acid and water?

Nashou

[zGman]

Well - yes there have always been cases of old cruddy housings with "fungus"
but they were more of an anomally due in part to age & poor maintenance.

This is a new phenomenon in my opinion - 'like new' & perfect housings growing
crystals in only a few months. Sitting in the same climate controlled environment
as other housings that did not grow crystals. The only variable was the bellows.

As far as testing - I think Matt is a masters level chemical engineer who works
in a well equipped lab. I am shamelessly volunteering him to analyze a sample.

Soaking the in distilled water (<$1/gallon at the grocery) for a few days might
help, as might rinsing with isopropyl alcohol before install.

"Bare" aluminum is not actually bare, it is always coated in aluminum oxide.

""Anodizing, or anodising in British English, is an electrolytic passivation process
used to increase the thickness of the natural oxide layer on the surface of metal""

I think the involvement of aluminum in the observed long term degradation of
Marquee housings is related to the chemistry chages due to the the osmotically
absorbed water that accumulates over time. Possibly the pH changes as the water
splits off some OH-, and possibly there is some electrogalvanic action,
or probably there is both going on and driving each other to occur.

The sharp edges of the exposed fill screwhole threads will act to concentrate
any electrical field - and lets also consider the 35KV hitting the tube face close by.

Bear in mind though that Barco LC housings last for years with no issues, the glycol
might get a little discolored but never have seen any corrosion or "fungus" - Same for
Sony G70 and G90 housings.

Barco Bellows never seep or weep and don't have to be changed, and can't be infact,
they are glued in. Sony used metal bellows, which was nice, but they also have
an expansion chamber which uses a accordian type rubber expanding diaphragm.

G