650b conversions, some new bikes, all nonsense

Thinking about the BB shell, I realised it would be the easiest to sweat in a shell and then cut threads into it. I'll have a crack and some more measurements to see if it's going to be possible.

I realised it would be the easiest to sweat in a shell and then cut threads into it.

Wouldn't it be easiest to use a shell with threads already there?

Update!

I managed to sneak in a day in the workshop, and made some awesome progress.

I now have a plan for the BB, it's overally complicated and required the purchase of stone fancy tooling, so I need to wait for that to rock up. Spend most of the day planning that.

Other progress:
Got the front brake bosses on, and to say the least, I'm bloody chuffed. It was really hard brazing them on there the crown lug was right behind so it required a huge amount of heat and I could only find the smaller tip for the torch so it took ages but we got there in the end. The fillets are bad, so I'll file them later.

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I think the brakes look brilliant so I was stoked on that. I'm an effort to put off the internal cable routing, I put in the bottle bosses. Got to say, I really like silver soldering as a process.

Also a bonus pic of the hardest working bit of kit I have, my everything jig. That bit of steel and bailing wire has been the most frustrating thing to date, but it was easier than making a better tool.

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While I had the torch out, a pal asked me to chuck on some bosses on a frame he found in a skip, and as I did it at the end of the day, they came out really nice. As it was Friday, I would like this to be my fillet Friday submission.

For those that are curious, I'm cheating a little, I have access to a gas in line flux which makes everything so much easier. Bonus knowledge, the difference between gas in line and applying flux paste is the bronze will flow where I apply heat, as the flux is mixed with the gas. If you use paste, the bronze will flow where the paste has been applied, which makes it harder to keep a tight bread.

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So this is the conclusion I came to, but I want to ensure the threads are co axial, and the internal diameter of the shell is currently the major diameter of the threads, meaning I would have to braze in just threads, which might be impossible. So my current plan is to bore the shell on both sides in the mill, and then either braze or loctite in steel shells, bore then and then cut threads.

More moreeee!
My build threads are so boring, love this :)

BITD people did a "cut and shut". Cut the bottom bracket, closed it up and cut new threads. Sort of made redundant when threadless BB arrived.

I was more thinking, remove current shell and replace. Probably only viable if it’s fillet brazed or lugged though, not so on a welded frame.

I see the logic in this but is horrifying to me. It would shorten the wheelbase no?

I had considered this, but honestly the crazy mill setup is easier. After measuring the frame, the BB is well centered and in good alignment, so moving it seems a bit crazy. I think for the minute, I'm going to crimp the chainstays and go from there.

Great thread, subbed!

I was thinking about paint the other day. I had orginally thought about just getting a single colour powderesq job done and having some nice logos but then I thought back to a frame I owned a number of years ago (that I heavily regret selling) and figured a cool homage to that might be cool. Ill take any Look based puns for the name of the frame. I really loved that frame. If you have one in a huge size, hit me up. Ill have it for a resonable price.

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No change to wheelbase. A thick slot is cut on the underside of the BB shell and the shell forced closed. This reduces the diameter of the BB shell.

The shell is brazed / welded back together and new threads cut.

Very crude but I am going back 50 years lol

After getting back from a rather long and overdue holiday, I saw this frame sitting in the workshop looking a bit sad.

As the weather went from decidedly grey to quite nice and grey I have concluded I need to get this bike on the road as soon as possible, and due to all the pitting and rust I'm not sure it's worth putting much more effort into incase I don't like it. As such, I brazed on the down tube cable adjusters (they are neither straight or symmetrical, but you can't tell unless you look closely) and a cable stop for the rear derailleur. Going to try to dimple the chain stays tomorrow.

My intention is now to rattle can this and start riding it to see how it goes.

I also had this complex plan for threading the BB shell, but I think I'm just going to get the external damaged thread bb and face the sides of the BB till it fits.

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Somehow missed this thread. Really good stuff.

Rather than working on this I got distracted and got a new side piece. I had originally planned to rip off the geo of my old Karate Monkey, but I have a trip coming up in September and figured i would run out of time. I also picked up a new to me groupset off a mate that I'm very excited about, I've never had campy.

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Best mechanical groupset ever.

I would consider having a fork mounted cable stop rather than that headset hanger otherwise you'll get horrible horrible fork judder.

I'm hoping so.

Is the judder because the headset hanger isn't stiff enough/long cable means it will flex and doesn't apply a constant force?

I'll give it a go, see what it's like before I buy something else, but thanks for the tip.

It's because the fork isn't stiff enough and so the brake moves back and forward in relation to the cable stop applying an oscillating force to the inner cable.

^what @leggy_blonde says. I changed from headset hanger to fork mounted - night-and-day improvement. I think it was something like a tenner from Condor.

Great thread. I've often considered converting a frame to 650b, or should I say having a framebuilder convert it for me.

Looking forward to hearing your opinion of how it rides when it's finished.

Made a good bit of progress today- managed to dimple the chainstays, and get the internal routing finished.

Turns out, internal routing is really hard. If you have a hand built frame with internal routing, go and give your frame builder another £500, a hug and some biscuits. Granted it was harder for me because I'm doing it to a complete frame, but still. Fuck me.

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Also there was a small shoulder in the BB I managed to tap some threads into, which means I could get a BB in there for a testing. It's so cool. With the wheels and tyres on there it's really starting to feel like a bike. I'm so excited.

Also tidied up a few things, got the routing over the BB done, all the cables are ready. Once I sort this BB nonsense I can start riding.

Just a little last point I want to make. I am unbelievably proud of this. It's not that amazing, loads of people have done more and better-but the few hours I manage to spend in the workshop each fortnight brings me an alarming sense of joy, I leave smelling of metal and coolant, with a wide smile.

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Hey. Good work on getting it done. Looks to me like you used some pretty chunky tubing for this? I might be wrong but I do wonder if that's why you were struggling. I use specific internal stainless steel tubing from Ceeway and find making internal routing extremely easy on both built and non built frames. There has been some good videos in my Instagram feed that shows the process. Both Saffron and Alex Meade did videos I think, where they just use a hand drill and an end mill (or some grinding die).

Maybe I can make a video of my process next time I do it. I've both done slots on a proper mill setup and cowboy style using a hand drill and I prefer the cowboy method to be honest.