Shiny From Germany, joined May 2012, 22 posts, RR: 0 Posted (11 months 3 weeks 3 days 16 hours ago) and read 2212 times:
Good morning/afternoon/evening gentlemen,
while being a rookie here, I start with a concrete question:
I am currently working on some instructions for removal of advertising decals (3M film) from the tail of a B737. The normal removal procedure includes either a hot gun or steaming unit (to soften the film and make pulling it off possible).
I have hard time finding the maximum temperature that can be applied to the skin (without affecting surface integrity, paint etc.)?
Tristarsteve From Sweden, joined Nov 2005, 3687 posts, RR: 34 Reply 1, posted (11 months 3 weeks 3 days 14 hours ago) and read 2181 times:
Well this is from the depths of my memory, so please check,
but Concorde had an aluminium body. In supersonic cruise the skin was heated by friction. There were temp sensors on the leading edge of the wing, and at 121 deg C they slowed the aircraft down to stop it getting hotter.
No idea where 121 deg came from, just something I recall (probably wrongly).
Shiny From Germany, joined May 2012, 22 posts, RR: 0 Reply 2, posted (11 months 3 weeks 3 days 11 hours ago) and read 2100 times:
Well, this is a good starting point, but does anyone have more accurate information specifically in reference to B737 or general public aircrafts? I failed finding one in the official 737 manuals I have (either don't have the right one or am being blind)...
n901wa From United States of America, joined Oct 2009, 382 posts, RR: 0 Reply 3, posted (11 months 3 weeks 3 days 10 hours ago) and read 2037 times:
I am not 100% sure. But I think you might have to go to Boeing and get a EA to use that type of removal. I am not sure how Big the Ad will be on the Tail, or what type of 737, but if they go over Composite panels or on thr Rudder Heat might become a issue. I know on the Fues the 3M Decals I have seen are just applied and edge sealed. And when removed can just be carefully pulled off. I bet there is a Boeing Finishing Manual that is not covered in the AMM or Line Manuals. You might also want to check with 3M and see if they have a aproved process that Boeing have already bought of on for the product. HTH, and Good luck.
Shiny From Germany, joined May 2012, 22 posts, RR: 0 Reply 4, posted (11 months 3 weeks 3 days 5 hours ago) and read 1984 times:
I am actually creating the EO for removal in this particular case 3M refers to the aircraft manufacturer (of course... since the film is universal and can be applied on different aircrafts) for more information about maximum acceptable skin temperature.
I on the other hand fail to find this information from Boeing... I have a rough idea about what should be considered "acceptable" temperature, but since this is an official document, it should not be based on assumptions.
Other than that - 3M suggest using hot gun or steaming machine to soften the film before removal...
Chemicals can be used too but I am trying to avoid that. It is also less time efficient.
tdscanuck From Canada, joined Jan 2006, 12709 posts, RR: 81 Reply 5, posted (11 months 3 weeks 3 days ago) and read 1914 times:
Quoting Shiny (Reply 2): Well, this is a good starting point, but does anyone have more accurate information specifically in reference to B737 or general public aircrafts? I failed finding one in the official 737 manuals I have
A starting point would be the SRM; you definitely don't want to go over the cure temperature for the composite that you're working over. That's an upper bound though...the OEM may recommend a much lower threshold.
Quoting Shiny (Reply 4): How is edge-sealing removed though, any idea?