# How forgiving is Reynolds 531 tubing?



## ric426 (Jul 23, 2004)

The initial question is probably a good one for the Bikes, Frames and Forks forum, but it applies here because what other forum would have members grinding fittings off of otherwise perfectly good frames?
I hope I didn't screw up too badly. I'm sure I'm not the first, so maybe the solution is at hand. I did a pretty good job of grinding the fittings off the frame I'm converting to fixed gear, except for the shifter mounts on the down tube. Apparently I went a little too deep with the Dremel tool and didn't even realize it until I started filing the areas. Some of the grind marks are into the outside surface of the down tube, but not even close to going through the wall. It's not excessive (I hope...), but enough on both sides that I'm concerned about the integrity of the tube and the long term safety of the frame.
How thick is the tube wall likely to be about 3.5" from the headtube lug? Depending on that, the way I see it, I've got a few choices:

A. Retire the frame and chalk it up as a stupid learning experience.

B. Have my son lay down some light welds to fill the mistakes and carefully grind them flush with the surface. Besides using too much welding power and blowing through the tube wall, are there other problems with this approach?

C. Silver solder a nicely shaped steel patch over each side to reinforce the area. From what I understand, silver solder is strong, but is it enough for this purpose?

D. Braze the same patches in place using brass brazing rod. Seems like it'd be strong enough, but it's been a long time since I did any brazing and never on a bike frame.

E. Just fill the mistakes with body putty and paint over it. This doesn't seem sensible unless 531 tubing is a lot tougher and forgiving that I think. I guess it also depends on where the stresses are on a downtube at that location, but I'd feel a lot safer riding it if the area was reinforced somehow. I'm not all that light or all that strong, but it seems to me that climbing with a fixed gear bike puts some extra stresses on the frame no matter what.

So aside from telling me what a bonehead I am (I already know that very well), anyone have any helpful comments? Is this a recoverable mistake or a painful lesson?


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## ethebull (May 30, 2007)

The wall thickness of your down tube is .9mm at the butt and .6 in the center +/- .1 The taper occurs right in the neighborhood of where your shift bosses were = where your damage is now...

Brass would be my choice for a repair patch, but a down tube replacement would be the pro way to go. Best to bring it to a frame repair expert for evaluation if you have one locally. Where do you live?


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## ric426 (Jul 23, 2004)

I'm in southeast Michigan between Ann Arbor and Flint. Too bad Mark Nobilette moved to Colorado years ago. I don't know of any current frame builders in the area. 
I wouldn't put the money into this frame to have the tube replaced though. If it can be patched safely I might go for it, but I'm not particularly attached to this frame and I don't think it's anything special, so if I screwed it up any worse than that I'll scrap it and move on. 
Between paying for a repair, having it sandblasted and repainting it, I'd probably be better off putting the money into a frame that wouldn't need to risk it's life by having me approach it with any tools other than the ones needed to assemble the bike. I can do that pretty well without trashing the bike.


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## ethebull (May 30, 2007)

I worked at Proteus in College Park Md from 82-93. We built frames, offered repairs, and sold everything frame building related to builders and hobbyist builders, so the notion of an average Joe - home repair approach doesn't make my skin crawl. Far from it! We were _the _source for home brew frame kits and bits for years. If you have access to an oxy-acetylene torch rig, try the brazed patch. 

This is the closest builder in your neck of the woods that I came up with:

http://www.sisucycles.com/ContactUs.html

Good luck.


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## redxj (Oct 22, 2005)

Matt Assenmacher in Swartz Creek I believe still does repair work.


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## RHankey (Sep 7, 2007)

If you think you ground enough to warrant a patch, I'd use silver solder, as I beleive that's what was used for many lugged frames (or at least, that's how I made a couple frames 30 years ago). Silver solder flows better, but more importantly, requires much less heat, so is less likely to damage the strength of the tubes.


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## ric426 (Jul 23, 2004)

That's what I'm thinking of doing. My son's going to a welding shop tomorrow and he's going to find out what alloy they'd recommend for this application. I've got years of soldering experience and he's done some brazing, so between the two of us, we should be able to accomplish something. If it goes well I'll try using the frame, but if I have any doubts I'll keep it for spare metal scraps.


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## Dave Hickey (Jan 27, 2002)

This link might help

http://www.bikewebsite.com/weldbraze.htm


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## ric426 (Jul 23, 2004)

Thanks so much! That is extremely helpful.

Do I need to be too concerned about the shape of the patches I put over those areas? I was planning on making a couple of elongated diamond shaped pieces with the longer ends pointing along the tube to make them at least a little ornamental, but I don't want to introduce any stress risers in the process. Would I be better off using a shape without points or is it not a big deal?


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## boyd2 (Apr 21, 2003)

ethebull said:


> I worked at Proteus in College Park Md from 82-93. We built frames, offered repairs, and sold everything frame building related to builders and hobbyist builders, so the notion of an average Joe - home repair approach doesn't make my skin crawl. Far from it! We were _the _source for home brew frame kits and bits for years. If you have access to an oxy-acetylene torch rig, try the brazed patch.
> 
> This is the closest builder in your neck of the woods that I came up with:
> 
> ...


Hey I worked at Proteus in the 93-94 time frame. John Boyd here, do we know each other?


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## ethebull (May 30, 2007)

Nice linked article on Brazing. Silver is just lower temp brazing. With brass, you'll get the temp up to the point where the tubes glow orange, with silver you'll barely need a dull glow before it flows. The wetness of the flux is a good indicator (different flux is used for brass vs. silver). Take a couple of hours to practice with some scrap materials, getting a feel for the process before attacking the real repair. Don't do too pointy a diamond.


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## ethebull (May 30, 2007)

sent you a PM, Erik Ewald here. PM me and we can exchange personal emails. I'm sure we have some mutual connections at the very least.


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## ric426 (Jul 23, 2004)

I silver brazed the first patch on tonight and so far so good. Had to do some filing to clean up a couple spots where I applied too much material, but IMHO, it looks good. My son's a mechanical engineer with a lot of frame and suspension experience on off road vehicles, so I let him specify the patch shape.
I'll post some before and after photos tomorrow.


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## Dave Hickey (Jan 27, 2002)

Please do....This is something I've always wanted to do....


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## ric426 (Jul 23, 2004)

Well, I can make a heck of a mess of things, but at least I'm good at cleaning them up.
Here's a before pic and a couple of after. I've got a couple more showing a little of how I made the patches if anyone's interested. It turned out well enough that I'm going to get the frame and fork sand blasted tomorrow and will start some rattle can painting this weekend.
I found that as I got more brazing under my belt I was able to use just enough brazing wire to do the job, which meant less filing to remove the excess. Practice makes sorta perfect.
I don't know why the system insists on showing the photos out of order, but you get the idea.


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## Dave Hickey (Jan 27, 2002)

ric426 said:


> Well, I can make a heck of a mess of things, but at least I'm good at cleaning them up.
> Here's a before pic and a couple of after. I've got a couple more showing a little of how I made the patches if anyone's interested. It turned out well enough that I'm going to get the frame and fork sand blasted tomorrow and will start some rattle can painting this weekend.
> I found that as I got more brazing under my belt I was able to use just enough brazing wire to do the job, which meant less filing to remove the excess. Practice makes sorta perfect.
> I don't know why the system insists on showing the photos out of order, but you get the idea.


That looks fantastic....Great job...


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## ethebull (May 30, 2007)

Hey! Nice save!

I'm sure you wish the repair hadn't been necessary, but no harm no foul. Got to bone up on silver brazing and have some fun along the way. Not many cyclists would be so fearless. You can proudly display those down tube patches as badges of honor ;-)


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## ric426 (Jul 23, 2004)

Thanks guys. I feel a lot better after fixing it than I did after screwing it up. Got it sand blasted this morning and dropped it off at the powder coater this evening. With luck I'll be building it up this weekend.


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## redxj (Oct 22, 2005)

ric426 said:


> Thanks guys. I feel a lot better after fixing it than I did after screwing it up. Got it sand blasted this morning and dropped it off at the powder coater this evening. With luck I'll be building it up this weekend.


Let me take a wild guess Superior?


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## ric426 (Jul 23, 2004)

Wow, that's a pretty good guess! Are you in the Fenton area?


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## redxj (Oct 22, 2005)

ric426 said:


> Wow, that's a pretty good guess! Are you in the Fenton area?


Nope, north of Ann Arbor. They powdercoated a frame and fork for me last week, and I can guarantee they will see more of my business as well. (Hint: You also bought that Falcon frame/fork from me )


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## ric426 (Jul 23, 2004)

Hah, small world, huh? Did you have yours sandblasted at Master Blasters too? That's who gave me the number for Superior. Kim at Superior said they do a lot of bicycle stuff. Glad to hear first hand that they do a good job. Can't beat the price. A place in White Lake quoted me $150 for powder coating and $50 for the guy who does all his sand blasting! I'd send it off to Olympic in CA before I'd pay that.
I've got some good ideas for lettering and trim on the frame that should look good. Originally it was just going to be a beater bike, but I've really gotten into doing it up nice, even with my mistakes... At least I've got a little experience in silver brazing now.


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## graw (Jun 2, 2007)

ric426 said:


> Hah, small world, huh? Did you have yours sandblasted at Master Blasters too? That's who gave me the number for Superior. Kim at Superior said they do a lot of bicycle stuff. Glad to hear first hand that they do a good job. Can't beat the price. A place in White Lake quoted me $150 for powder coating and $50 for the guy who does all his sand blasting! I'd send it off to Olympic in CA before I'd pay that.
> I've got some good ideas for lettering and trim on the frame that should look good. Originally it was just going to be a beater bike, but I've really gotten into doing it up nice, even with my mistakes... At least I've got a little experience in silver brazing now.


Just curious how much Superior charges for a frame.


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## redxj (Oct 22, 2005)

graw said:


> Just curious how much Superior charges for a frame.


I gave the frame and fork to them to have stripped and powdercoated. The stripping they farm out and was $25 and the powdercoat was $50 for a single color for frame and fork.


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## ric426 (Jul 23, 2004)

*Success (I think...)*

Well, I guess I pulled it off...
It's just put together enough for photos, but I'll post it in the " Post pictures of your fixed bike here" thread when it's all together.

Before:











After:


















I was going for a "nice frame feel into the wrong hands" kinda funky look. I guess I got it.


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## threesportsinone (Mar 27, 2007)

Very nice, I like the s.o.s theme with the morse code on the TT. You did a very nice job with the patch as well I had to look at the pics a second time to find it.


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