I picked up a 1985 Trek 720 to restore, and found this stuff on the side of the top tube. Anyone know what it is/how to remove it without damaging the frame or much of the paint?
Resin maybe?

Also, while I have you here...anyone know what this flaky stuff in the seat tube is? I've read not to worry much about a bit of rust as long as I clean it out. But the flaking is a bit weird?

Frame saver maybe? Can you use a fingernail to scratch part of the stuff off the top tube?

weird - is that a blistered decal? looks a bit bubbly.

it think there was some galling in your seat tube (with the seat post). My LBS has this drill attachment. It's got all these little stiff wire brushes that would kind of clean that up. It's kind of like a burnishing tool, maybe. A quick google search didn't find it for me. But I would think a quick touch up with a DREMEL wire brush or something similar would smooth things up for you.

https://en.wikipedia.org/wiki/Galling

A very small amount scratches/comes off to my fingernail mostly it's pretty hardened on

Ooh good to know. Thanks! Don't think it's a blistered decal. It's pretty hard and doesn't feel like vinyl or plastic

Too bad there isn't a clear top coating on the frame because there is a danger of removing the decals.
The stuff on the tube might be glue, if this frame was mine I would get a q-tip and wet it with water and dab around the edges to see if it softens (staying away from the decal)...if that does not help, I would try mineral spirits in the same way...if that seems to soften the goo great...looks like a bit of the decal has already lifted...be careful and good luck.
Best, Ben

Looks like old dried epoxy or some other form of glue. Or maybe it started off as tree sap; if you get lucky you might even find a mosquito frozen in amber! Perhaps he was the most hated guy in the club and it's an old loogie (lugie?) that never got wiped off.

I try not to think too much about what precisely I'm cleaning off of a new acquisition.

Oh, and those are clearly alien spores inside the seat tube. Clean or quarantine, but do it quick.

I think [MENTION=348967]Fahrenheit531[/MENTION] may be on to something. The stuff on the top tube looks like the sap that the Douglas Firs dropped on my car at my last house. If it's sap rubbing alcohol, applied carefully, will eventually remove it. Careful though, a little bit each day and rinse well after each use. It can remove the paint too.
Brent

Careful!, it might be a rider's lugey that hardened and petrified itself on the top tube!

Haha... Well regardless despite my initial frustration I managed to get it off without too much additional damage to the decal. The bike is pretty scuffed up, but otherwise in good shape to ride once I get the new wheels, brakes, and rear derailleur on...

I wouldn't mind seeing the whole bike as it is now, as "before" pictures.

Nice bike. 720 has a great ride. Enjoy!

[QUOTE=Fahrenheit531;20983882 Or maybe it started off as tree sap; if you get lucky you might even find a mosquito frozen in amber! [/QUOTE]

This - It's pine sap / resin

My immediate thought, before reading through the posts, was also tree sap.

Looks like rust to me

That would be my guess- once that stuff is on- it’s very “on.”

I’m glad you got it off.

aka balsam in our neck of the woods. One of my late mother's early-married-life cookbooks contains this transcription of an observation from (?three-year-old) me: "Giggy [my first attempt at saying "Grandpa", which stuck] uses Esso Escra to get the blossom off his hands." Context unknown but preserved lovingly to this day in my sister's attic.

And since we've gotten this far into the thread...

A 1985 Trek 720 you say...

MORE PIX!!!


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