leading

Unless it's a light weight bike that was made with stretched tube. THey do that, you know...

Filling the dents with solder seems like a lot of work for what will be a cosmetic repair. There are sand-able fillers for use beneath powdercoat, as described at this thread:

note also that the reason the frame is thin is to reduce weight - a good frame from the 1960s would be .020 thick Reynolds 531 tubing, double butted - it would be criminal to undue that by adding lead. (I have a Winsor bike, of the type that won the tour de California ridden by Eddie Merx - some day I'll figure out what to do with it, I bought it new but it's very short coupled and uncomfortable to ride as a touring bike)

Well, why not just sand it then?

Thanks, Rich

Because the tube wall is only about a half-mm thick.

Ah Ha! Now that is something I didn't know. Thank you.

I can use a fairly low temp. silver braze that I know will be safe for powder coating. The reason I had for using the lead was that it is much softer then the steel and so easier to file down flush without taking too much off the tube.

I guess it would have turned into doing it the easy way only to discover that the easy way got considerably more complex and costly by the time you got it finished.

Yes, the powder coating guys briefed me on that.

Since I've got you (so to speak :-) I had given some thought to trying to do a two color powder coating - spray the frame and bake one color. Then mask off the portions that are to be the initial color and spray a second color and bake again. The second coat would be darker then the first coat, if that matters, and I also believe that the thickness of the second coat would show. I also understand that the masking tape(?) is fairly stiff so the masked edges would be pretty much straight lines but I can live with that.

Any words of wisdom here?

I should have said. It is a strange one to me too. It was built in Japan and when I bought it had 26 x 1-3/8 wheels and tires, cantilever brakes, drop bars, fenders and a carrier. Standard 52-39 road sprockets, 7 speed and a 2 Kg. lugged frame.

I bought it to make over into a semi touring bike and replaced the wheels with standard MTB 26" wheels and had to move the brake studs. which began the whole frame project.

Nope, it is a lugged frame with what appear to be double butted tubes.

You are probably correct however I live in Thailand and there doesn't seem to be that much market for powder coating and thus not that much material available. The place that are doing my frame has six colors available.

Yes. As well as I can measure the tubes are in the neighborhood of 1/2 mm in thickness. What I was trying to do was to fair the dings and scratches accumulated over 30 years and for the cosmetics only.

That sounds like a fun project. Just two weeks ago I finished a bike project, which I hadn't done for years. I converted my son's Raleigh mountain bike into a heavy-duty commuter (with 26 x 1.5 road tires, etc.). I was surprised at how light the frame is, despite large-diameter tubes. He's

23 and has suddenly developed a renewed interest in bicycling, and now he's riding all over Washington, DC with it.

I wouldn't have thought of powder-coating a bike frame, but I'm not familiar with having it done. My thought would have been for two-part polyurethane, but I'm not equipped for spraying that stuff, either.

And Lab-Metal will handle 425F (218C) for up to 20 minutes... so, again, use Lab-Metal.

Essentially what I'm doing, although I'm also learning about touring at the same time. Standard road gearing is not what you want, or at least not what I want, for cycling long distances in hot weather :-)

I initially thought about painting with two part paint and have access to either the gear and/or people to do it for me but when I ran across this powder coating place their price was cheaper then I'd have to pay for the two part paint as it is only sold in gallon cans here. And, as the paint place is a friend's I'd felt beholding and would have had to offer to pay his help for their time, and as I'm a friend I'd have had to pay the help over market rates to indicate my thanks, and, and.... the powder coating was cheaper :-)

Have the lad try a pair of 26 x 1.3 smooth tires. It turns the bike into a rocket.

The problem is that I doubt that I can find any here and shipping plus customs duties, etc., make the cost rather shocking :-)

There is a very wide variety of solders used in industry that have melting points ranging from 250 C to 450 C This is the best list I've seen. Considering the small quantity you need, maybe you can get some from a local electronics assembly plant or something:

That's a strong incentive to try powder coating. Not having the equipment, I haven't tried buying two-part polyurethane, so I don't know what sizes are available here. I want to try the brushable stuff some time to see how it behaves.

I'll keep that in mind. Right now, I'm pleased that he's enjoying it, and I'll try to teach him how to maintain it if he keeps up his interest. For the present we just needed a bike that he could ride in DC with a low chance of flats, and that he doesn't mind throwing into the luggage bin of a DC-to-NYC bus.

His dad is pleased because I got my car back when he moved to Washington. He can't afford to park it down there, which has been a boon for me. d8-)

te:

There's also this magic Indium/Lead/tin stuff from

lowers the melting point of regular 63/37 solder to 150C. This stuff is great for reworking large surface mounted chips - makes it a whole lot easier to get them off the board without doing damage.

But it surely isn't cheap. And what kind of temperatures do you need for powder coating? Maybe this stuff melts at too low a temperature.

There's also this magic Indium/Lead/tin stuff from

lowers the melting point of regular 63/37 solder to 150C. This stuff is great for reworking large surface mounted chips - makes it a whole lot easier to get them off the board without doing damage.

But it surely isn't cheap. And what kind of temperatures do you need for powder coating? Maybe this stuff melts at too low a temperature.

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John B and others are saying they need 200 C or more to powder coat.

Probably so but Bangkok covers some 15,000 sq. Km. and the telephone yellow pages have about 10 pages in it and the entries are all large companies. Trying to locate something essentially involves knowing where to look for it.

But, I am going to Singapore next week (where you can look things up in the phone book) and I'll have a look there.