Bike From Scratch

Look what I made

Today was a good day. I’ve got a complete (ish) bike! The main task of the day was getting the seat stays attached. First I had to cut the slot for my seat post binder and take care of all that, and before that I had to ream the seat tube to take a seat post, and before that….. you get the idea. Lots of little steps to get to where I was going. So I started the morning reaming the seat tube and freaking myself out a little bit with the process. I stuck the reamer in a vise pointing up and then spun the bike around on it by its seat tube. Unfortunately I don’t think I have a picture of this, Doug took one though so hopefully I can get it from him.

The next task was to cut a slot for the seat tube binder. Pretty straight forward. Stick two blades in the hack saw, draw a straight line, go to town. Don’t stray off the straight line. When it was all said and done I had a slot in the back of my seat tube. It pointed out how much I really need to do some finish filing on the back of my seat tube as it looks a little goofy right now. That’s work for when I get home though.

Cutting the binder slot

Finally after a few other odds and ends I got to working on getting the seat stays into my bike. The first step is to miter the stay to meet up with wherever its supposed to go. In my case I’m doing a fast back to the binder so I had to cut the shape of the binder in the top of the stay. Doug as usual was a huge help here and showed me a mercifully fast way to do it. It took the other guys the better part of a day to get their stays ready to go for alignment, I think it took me on the order of an hour. Just a couple quick hits with a file (the attachment I chose was much less intricate than what Daniel and Clifford were doing) and cut to length. The real trick for me was to get the seat stays to put equal tension on the chain stays. It took a few adjustments with a file, but nothing major. After the miter was done I was off to alignment. The process involves taking a true wheel and checking for center, making adjustments, taking the measurement again and working it back and forth until you get it right. This feels like it took forever but I think I only really spent a few hours doing it. I was pretty wiped by the time I got here though, its been a long two weeks.

Doug did the braze on the top side because it was a bit much for me (lots of small areas). There really aren’t words to describe his skill. It was unreal to watch him manipulate so much heat and metal in such a small space. After I got the seat stays setup so I could braze the bottom I took off back to the house for a bit. A classmate had ordered pizza and it was a nice pick me up before going back out to the shop. After dinner I brazed up the seat stays. I’m using stainless plug in dropouts from henry james. I love the little silver ring and watching it poor out the bottom in one shot when it flows correctly. Very satisfying. After the stays were brazed I checked alignment and everything was as I’d left it. As close to perfect as my first bike will be I think, and well within the (mostly made up) tolerances that we were told about on the first day of class.

Drop out brazed

The last big task for me was to get my fork converted from a 1 inch steerer to a 1 1/8 inch. I hacked off most of the one inch, beveled the top and brazed on a bigger 1 1/8 inch tube. This was a little nerve-racking as there was a lot of metal to heat up and we were not quite sure if the silver ring I stuck in the top ever really melted the way it was supposed to. I added silver and flowed it up the joint to the best of my ability. After we called it good and the fork cooled down we could peak down the steerer tube and see that the silver had indeed flowed as it was supposed to. So all is good in fork land for me, although with this particular combination the fork weighs a ton. I don’t care much about weight, and as long as handling is not effected I’ll just leave well enough alone. I do have the capacity to throw a carbon fork in this bike and A/B them so if it works out to be terrible I have that as an option I guess. I think the fork looks dope though, and most carbon forks are a bit ugly for my tastes. I’m sure it will all work out.

As far as on a personal level I’m glad we’re nearing the end and I get to head home on Saturday. I’ve been worn down the last few days and I’m ready to get back home to my wife and son. I got to see a really cool sunset on my way back to the shop that was a bit of a pick me up this evening, which really helped me stay positive and get through the rest of the stuff I had to do. I’ve had a ton of fun and made some good friends. I’ve been blessed with my classmates. I’ve been told every class gets along but I’ve really enjoyed the company of Clifford and Daniel. I’ll be posting a postmortem on the class with a full review and such in the coming weeks, as well as updates on where I am with finish filing and painting, but I imagine since tomorrow is just braze ons and reaming I won’t do another update from Michigan.

Sunset on my way back to the shop.

Day 10, already, really? It feels like the pace has been picking up the last few days. I went from a pile of unconnected tubes on Sunday to a almost complete looking bike today. I had two missions today, a binder bolt for my bike, and getting my chain stays installed. Both were a success.

The day started out pretty slow going. I think all of us are feeling the lack of sleep and missing our families. The mood in the shop is jovial though and we are enjoying the time we have remaining. If you end up taking Doug’s class and staying in his parents place, the coffee pot is a gift from the class of Feb 2010, use it wisely.

This morning I got to work on getting my binder attached to the top of my seat tube. We propped it up against the bike using some square blocks on the alignment table. Then I tacked it in place using brass. After I was satisfied that it was straight and looked good I headed off to do a fillet braze for the bolt. This braze was a bit more fun that the main tube brazes because I got to do more shaping. The underside of the binder has to be kept smaller so my stays can attach underneath it. The top needs to be filled out more to avoid a really harsh edge. I’m trying to avoid any harsh edges / sharp corners up where at the top of the triangle. The braze went swimmingly, Herbie was around for the assist if I needed it and to provide instructions / advise on the look of the joint.

Binder attached, just needs some finish filing.

The next major task of the day was to attach the seat stays. I was offered the choice of using the Anvil fixture or using Doug’s method that he learned in England when he was studying there. Doug’s method is longer but involves little in the way of extra tools (in fact I’m building the tool I need to repeat this process at home while I’m here). The process involves a lot of measuring, and being paranoid I was triple or quadruple checking everything. After all was said and done I came out with rear dropouts that put the wheel about .5mm off of center. I can fix this with a bit of filing on one of the drop outs (or I could leave it alone as this is a perfectly reasonable amount I suppose). I suspect I’ll file it as it will bug me if I don’t fix it. I’m really bothered that I didn’t get the rear end exactly correct.

Since we had some trouble with this method the class members and I have been brainstorming about possible causes. The current theory is that when we tack in the second stay something shrinks or expands and contracts and “sucks” the stay in a bit further. We found out after the fact that Doug does a bit of adjustment during the tacking phase that we didn’t do…. More info for the next bike I guess.

Attaching seat stays

I ended the evening with a bit of filing on my head tube to top tube fillet and making sure that I was all set to go for seat stays tomorrow. First I’ll need to cut the seat post slot, and then I’ll get to mitering for the attachment to the binder. I suspect I’ll also be adding some braze ons as well. I need a derailleur hanger and a few water bottle bosses. Hopefully these will be pretty quick and drama free. The other big task for tomorrow is getting my fork converted from 1 inch to 1 1/8 inch steerer. I detect lots of filing in my future for this.

Frustrating and slow to backwards progress was the name of the game for two of us today. I brazed up the first part of my bi-laminate lugs. This went pretty well and all seemed good. I started putting the frame together in the fixture and it looked well. I noticed Doug making faces at it so I asked again what he thought and if I should ditch it and just fillet braze the frame. For the first time since we started this endeavor he changed his answer a bit and since I was already nervous I pushed the issue. My line of reasoning was basically could I do it by myself or would Doug have to take the torch and bail me out. After confirming we decided that there would probably be quite a bit of bailing out and I get the feeling that Doug wasn’t exactly sure how to handle the bi-laminate with tubes smaller than the lug opening. I suspect this is one of those things he would figure out on the fly, but would be made more difficult trying to explain to me while I was brazing and he was doing the figuring out.

The beginning of the end for the head tube.

So we decided to switch, the existing head tube went in a box, and I pulled out the head tube I brought with me and cut it to length. We had to switch the seat post I had as well to an externally butted tube. The tube that was already brazed to my bottom bracket needed a lug at the top tube / seat tube junction to function correctly. I also had the option of creating a sleeve but the time and work this would take felt overwhelming and I decided to go with the externally butted sleeve.

So we had to remove the existing seat tube from the bottom bracket. This was done by putting a bunch of scrap parts (bottom bracket shells) on a wire loop and inserting the loop through the bottom bracket to add weight. We then heated the whole joint and waited for the shell to fall off. One of my classmates and I didn’t have much luck getting this to work but Doug came back to the shop and made the magic happen. It was good to learn how to undo a joint. So I guess there was a positive side to the exercise.

I brazed the new tube in by myself and that went pretty well. I was on a mission to at least be back where I started in the morning. I feel a lot better about silver brazing. I also did a practice fillet by myself. I learned some things about speed control and when to fill. This one looked no so great but had some good sections towards the end. I think I’ll do a bit better on the next practice one which I hope to do in the morning.

The other thing I did today was align my fork blades. This took out some of the extreme problems that I mentioned yesterday. It’s still a bit crooked but can be fixed with a smaller amount of filing than I was anticipating, so all is not lost.

Today was a good day. There were no major screw ups, nothing was caught in an angry Bridgeport and torn up, no one hacksawed the wrong thing, all of our parts showed up (okay so maybe there was one screw up) and most importantly, I had a really good braze on one of my fork drop outs today.

My chain stays and dropouts rigged in the Anvil

I started the morning filing up my fork crown waiting for the day to get going. I am about 1/4 done with that right now. I hope to finish that, and the rest of the filing I have to do Saturday night after Doug’s Sabbith and the shop opens up again.

When things really got going today I spent most of my day working on dropouts. First off I had to remove a bit of length from the end of my chain stays so the plug in dropouts would actually plug in. After cutting and making sure they were square I could figure out where the tire would sit in relation to the seat tube and the dropouts. Then I figured out approximate chain stay measurements. This is where my bike will differ the most from a traditional road go fast machine. The normal chain stay length for a race bike is 415mm or so. I’m going more towards the sport touring side of things with 430mm chain stays. This will allow me a slightly cushier ride as well as a ridiculous amount of tire clearance for my horizontal dropouts. Even at 415 I would not have any problem clearance problems for the 700x23c tires I’m using, but I really want a slightly softer ride, even at the expense of some nimbleness.

So first off I stuck the chain stays in the bottom bracket socket, then plugged my drop outs in and slid a tire in to check clearances. I had plenty of room even with the huge 700×32 tire that I was using. The tire is way bigger than anything I will be using but worked just fine for a test fit. After I settled on a chain stay length I more or less made a note of it and will be trimming them to length next week.

Non drive side rear dropout after brazing and cleaning off flux.

Now it was time to get brazing. Doug has an Anvil fixture that I used to hold the dropouts and chain stays so that gravity could do most of the work for us. The fixture rotates and we made it so that the head tube would be facing way up in the air, and the rear drop outs were pointed at the ground. After mucking a bit with the fixture to get it to hold the dropouts in place with no gaps I fluxed up the joint, popped in a silver ring and was ready to braze. Since my dropouts are stainless I had to heat them up a bit more than anything I’d done before. Brazing stainless requires the metal to get hot enough to be a bit red before the silver will flow. Doug showed me how and after a small worry about why the silver wasn’t flowing down quickly enough everything seemed to work out. The tube was a bit scorched after I was done but is was nothing a little filing wouldn’t take care of. We repeated this process with the second chain stay and now I have rear dropouts attached to chain stays! I think the most difficult part about this was the height of Doug’s Anvil required me to crawl around on my hands and knees to braze the joint. I don’t think there is anything that can be done to fix that other than getting some crazy tall stand. Not the end of the world but did seem to make something that was hard to begin with a bit harder. Thankfully Doug talked / helped me through it and everything is cool.

The next task was to work on the fork. First off was cutting to length after raking (bending) yesterday and getting the dropout to fit in the hole in the fork. I’m using plug in dropouts in the front as well as the rear, so the process is similar to what I described above. After it was all fitted we put the fork in another Anvil (I think) fixture to braze. This fixture is way cool because it doesn’t require you to crawl around on the ground like the Anvill frame jig did. It plugs into a Park stand and away we went. The first braze went fine, a little more scorching on the fork blade but nothing to get two worked up about. I then went on to the second blade with Doug’s apprentice Herbie watching over me. This is the best braze to date. No scorching, fairly good shore line etc. This felt like a big win for me and that maybe I’m getting the hang of brazing. I was so pumped that it came out looking as good as it did.

Finally a good braze! Dropout on the fork.

I spent the rest of the afternoon starting to file down all the dropouts I’d brazed earlier in the day. Some think the filing is monotonous and repetitive, but I find I really enjoy it. I like it quite a bit more than brazing. I like the slow change that I can cause in the metal I guess. (edit: after brass brazing I’m not sure thats true anymore).

Filing one of my rear dropouts.

In the course of filing one of my rear dropouts I did find a gap. That was a bit of a bummer, but Doug said it was nothing to worry about and that it would be fixed in paint. Nothing structural so it will all be well.

The one fiasco of the day came when the lugs I ordered finally arrived. I’m using the Slant 6 lugs from Llewellyn. I didn’t realize that when I bought the lugs they were for double oversize tubing. This means that they fit around my head tube but none of my other tubes. Since I’ve planned to do a biliminate (chop off the ends of all the lugs so they are only “around” one tube) bike from the start this isn’t a huge deal except for the seat lug. Instead of the cool (and well finished, which means less filing) Llewellyn lug I’m going to use a Henry James lug on the seat tube. Not my favorite, as the Henry James lug is smaller than I’d like, but not the end of the world either.

There is still quite a bit left to do, and it sounds like as a class we’re at least a day behind where we need to be. Hopefully since all of our parts have arrived (Clifford’s stuff came today too!) next week will speed up a bit and we will get back on track. As for my immediate future there is lots of filing on the horizon. I’ve got to chop off the ends on all three of my lugs, this is done with a huge file and some grunt work. I’ve then got to finish the lugs to make em look pretty. I’ve also got to finish my fork crown so it can get brazed up on Sunday. The shop opens at sundown tomorrow night and I’ve got my work cut out for me.

Figuring out chain stay length.

Lots more pictures can be found on flickr.