Primarily for general aviation discussion, but other aviation topics are also welcome.
By cockney steve
FLYER Club Member  FLYER Club Member
#1617840
Paint stripper (Nitromors) is Methylene Chloride plus a gelling-agent. As someone else suggested , body-filler (Bondo) is polyester resin with a very high chalk/talc filler-content...Methylene Chloride will soak into it and eventually soften it but the heat -gun idea is bang on the money. cheaper and you don't get high on fumes (OK the fumes are great, as long as you don't pass out, but the headache the following day ! )

I would guess that ordinary caulking- silicone would be OK to reseal joints....judging by your pix, there was a very poor bond with the "Bondo" (which is formulated to stick to steel motorbodies , there's a different grade for aluminium bodies), but neither is made for the sort of flexing your floor will undergo.
"Sikaflex "(google SIKA) is an air -curing Polyurethane...apply with a caulking- gun , permanently flexible , but you'll destroy the structure before you break the bond! motorbodies are glued together with one of the variants, as are modern vehicle fixed windows ! There may be one with a "solvent" of some sort, which you'd need if there was a need for future access.
Great writeup again Adam....still trying to decide if you're brave or foolhardy :lol:
2 Commanders and an Aerostar! -As if an XJS wasn't bad enough ! (had one (injection) - took about 4 hours to change the plugs, maintenance took about twice the time I spent driving it, the rest of the time was spent earning the money to pay for it! Did I mention the 12 MPG round town? :oops:
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By Bobcro
#1617919
Once you have safely removed the gunk and sealed the cabin, bearing in mind that you need to repeatedly remove access panels, you check for leaks by pressurising the aircraft on the ground without running the engines and setting off a smoke machine or none toxic smoke bomb inside. You being outside should be able to spot where it's leaking.

Be very careful when using any solvents to soften the adhesive and wear proper breathing apparatus for you may feel ok now but such fumes can do irreparable damage to internal organs and you won't find out until it's too late.
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By Flintstone
FLYER Club Member  FLYER Club Member
#1617921
Which reminds me of when an old hand of an engineer told me that back when smoking was permitted on flights fuselage leaks were easy to trace, they just looked for the streaks of nicotine.

Oh, and pressurisation outflow valves also gummed up more frequently for the same reason.
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By Adrian
#1617978
If you can find it, MEK solvent shifts that sort of gunk. It is horrible stuff, and Bob's health warning should be heeded. But it's great for removing old sealants, glues, mastics, and general decades-old gunge.
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By Flintstone
FLYER Club Member  FLYER Club Member
#1617989
Adrian wrote:If you can find it, MEK solvent shifts that sort of gunk. It is horrible stuff, and Bob's health warning should be heeded. But it's great for removing old sealants, glues, mastics, and general decades-old gunge.



And fingerprints, sinus linings, tear ducts........... :D
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By African Skies
#1618295
I’d also be very mindful to only use plastic or phenolic scrapers, not metal. The pressure deck is going to be a stressed component and any scratches or gouges in the floor could lead ultimately to a structural failure! Your A&P would probably not be too happy about signing that sort of work off.
#1618379
I use dry ice to remove sound deadening panels during car restoration. It makes everything so cold that it becomes brittle and you tap it with a soft hammer to break it up.
It works a treat but not sure if it serves a purpose for you.
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By AdamFrisch
#1618441
Plastic scrapers I tried and they just won't remove the stuff. It's really stuck to the floor. But I'm hoping the heat gun trick might do it. Plane still not back from autopilot shop in Tulsa: the only guy that can work on the antique H-14 is semi-retired and is only in 2 days a week... :roll:

The PRC or tank sealant for the inspection panels is of the B variety - especially made for panels that need to come off once in awhile. One has to try to stay away from any silicone based sealants as they add corrosion, so the tank sealants are the way to go.

http://www.ppgaerospace.com/Products/Sealants/Specialty-Products/PR-1428-ClassB-Access-Door-Sealant.aspx
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By Bill McCarthy
#1618453
I’d be very wary on using dry ice on the panels - local contraction in the aluminium may warp things and stress rivets especially if there is any water trapped between overlays - may be ok for a banger. The important thing is to keep carbon based material and anything alkaline well away.
As an aside, bathroom sealant was used, apparently, to glue heat shield tiles to the space shuttles. I would thoroughly research a solution to the problem before committing to diving in with any old material.
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