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Help finding a Chromic Acid Anodize and BR-127 Primer Application Processing House with 22+' tanks

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Go Bears

Aerospace
Oct 18, 2018
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I am looking for a processing house that is extremely well versed in Chromic Acid Anodize and BR-127 Primer application. Preferably in Southern CA but at this point I am willing to ship parts to any near by state. I have a bunch of 22' long parts I need processed for bonding. I have wasted years trying to get various local processing houses (with long enough tanks) trained on the necessary steps but if I am not there to baby sit every single lot we get unacceptable quality. I keep getting product where they are either blowing the windows, not applying the primer properly, or not curing it properly. At this point I am looking for a processing house that is truly an expert in the process. Any leads or advice is greatly appreciated.

Thanks!
 
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Go Bears ,
I had a similar problem earlier in the year, I found 3 companies , one in Oxnard , One in Temecula Ca ,and one in Ontario Ca.
Do a search in those towns.

You are judged not by what you know, but by what you can do.
 
Thanks. I just found the one in Oxnard. I'll be calling them today. If we are not allowed to post the names of businesses, can you give me another search term for the one in Temecula and Ontario?
 
Go Bears ,
This association might be able to help There is also an outfit in Carson that might have bigger tanks. When I was looking we were able to curl the wing skins up to fit a smaller tank.
They are called Valence surface technologies, they also have another facility in Paramount.
B.E.

You are judged not by what you know, but by what you can do.
 
Go Bears... Adhesive bonding application... odd request(?)

Why Chromic Acid Anodize [CAA] with BR-127 adhesive bonding primer... why not Phosphoric Acid Anodize [PAA] with BR-127 adhesive bonding primer?

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
Go Bears... BTW...

I have worked with a vendor who hard-anodized large ~9.0-inch OD X 25-Ft Tubes... the vendor made a special long-tank, special holding fixtures, 'masks', EE-contact tabs, cut-off tabs, etc, for those parts. Did a very nice job at premium price.



Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
My company makes main and tail rotor blades for helicopters. These particular parts are for an older product line and our current FAA approvals are only for CAA. I'd have to go through a ton of paperwork with the FAA and testing to get PAA approval. I know it shouldn't be that big of deal, but I recently got approval for modifying our Titanium processing to include Sol-Gel and it took 2 years. Even though Sol-Gel is a well established process, they made me go through a ton of extra static testing, fatigue testing, peel tests, hot/cold tests, environmental exposures etc. I've been told by the elders in my industry that CAA has better corrosion resistance and bonding properties than PAA and that the main reason for the switch to PAA was environmental issues. So there is hesitation here to switch for those reasons as well. CA is slowly trying to chase out Chromium though. I helped design a zero emissions system for a local processing house to help keep their CAA line up and running for our other products. Unfortunately, they don't have tanks long enough for this particular product line.

I am very familiar with Valence, they use to be Coast Plating. They are currently running these parts for us but they are not experts on Bonding Primer Application. I keep getting parts back that fail wipe testing. The bonding primer wipes off with acetone. These are critical parts and the correct processing is essential. If I am there baby sitting each lot all day they do fine. But I can't afford to spend my time at a processing house every day. I need to find a place that knows this process inside and out and can be trusted to run it without strict supervision.
 
Hmmmmm...

...I've been told by the elders in my industry that CAA has better corrosion resistance and bonding properties than PAA and that the main reason for the switch to PAA was environmental issues...

PAA emerged as a result of the MAC-DAC PABST program run in the 1970s to develop/mature structural adhesive bonding. PAA demonstrated superior mechanical and durability properties when coupled with appropriate primers, relative to all other anodic coating, or 'other' surface-prep coating systems. Although PAA has poorer environmental resistance, by itself [as a surface prep], it develops a far more [consistently] durable bond-line as evidenced by all tests wedge-testing and durability tests... which extends environmental life significantly... and real-world experience... is very consistent.

just-saying...

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
PABST = Primary Adhesive Bonded Structures Technology

NOTE. PABST lead the way... lots of other PAA/adhesive-bonded structure documentation is also available.

My company is 100% on-line with PAA process of aluminum alloy parts for general adhesive bonded assemblies.

Sol-Gel [silane based surface prep] was found to be almost as good... especially for repairs and for 'small shop use'... but PAA retained certain advantages... especially in large shops set-up for high-volume production.

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]
 
This is a vent not an answer, but related you can delete it if needed, I just got a PMA'd part for an aircraft made by a well known aftermarket parts maker. The parts came etched and primed " All I had to do was paint them.". A couple of areas the size of your thumb the paint flaked off while I was scuffing the part, I figure, ok somebody was not careful with fingerprints. I fix those areas and continue sanding, more paint flakes off. At this point I get suspicious and do a masking tape check. This fails miserably, I have just paint stripped the whole part by just putting masking tape on and lifting it. I am not happy. The good news is that I did this before I shot any paint on it.
B.E.

You are judged not by what you know, but by what you can do.
 
Well I had two of those parts, the second one also failed the masking tape test, but not as badly. So to make sure I used paint stripper, cleaned it off to find the surface just as shiny as the other. So Phosphoric acid etch, then conversion coat with the very last of my old yellow Alodine CAA . I guess now I have to go out and buy PAA for the next job. Epoxy strontium chromate primer on. now I am back to where I was Friday evening, all I have to do now is shoot top coat. I love Aeroplanes.
B.E.

You are judged not by what you know, but by what you can do.
 
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