Silver Case

The star-fangled nut of my Dahon headset lost its grip. I’ll have to replace it with a beefier carbon-tube style clamp I guess. Therefore, I had to take my road bike to work today, which was fine. It has quite a bit of toe-overlap, which makes low speed traffic navigation more tricky, but it didn’t turn out to be a problem. And it’s certainly faster than the dahon.

Today’s telemetry said I rode 16.51km averaging 26.1km/h max speed 46.2km/h in 37:55. I have a lot of traffic lights along the way, so I am not sure how that accounts in the averages and times.

Replaced an old Cateye speedometer (which wasn’t hearing the magnet) from my tri bike with a new wireless cadence/speed sensor this evening. I’ll try to resuscitate the first one and stick it on my Dahon. I have a second, wired, Cateye for Le Chacal.

A few years ago I bought a Silca floor pump for my bicycle tires. They’re the snob-friendly Italian tire pump everyone rants about lasting for decades. In my experience, it’s pretty much an overpriced piece of retro-shit.

This afternoon I bought a replacement rubber gasket for the presta valve connector. It was disintegrating, making it hard to attach the pump to the tires, as well as hard to get a good seal.

Later this evening, I was topping off my road tires with the pump when the handle collapsed underneath me. The pump was no longer creating any pressure.

I tore apart the pump easily. The cheapness of the build was appalling.

There is a plastic guide at the top of the steel chamber. It’s “attached” with two stubby wood-screw style screws. That will be good for two, perhaps three, re-tightens. They hadn’t even drilled pilot holes, so the whole plastic assembly is a ripped mess. If I have to fuss with this pump many more times, I can imagine needing to drill new holes for the screws to find a bite.

Why did the pump lose pressure? Because there is an apparently cheap piece of leather formed into a cup, and bolted to the end of the pumping shaft. It had simply torn where the leather is pinches by the bolt. Dumb. If they want to use leather for something like this, at least use good leather, or lubricate it with something more appropriate than cheap grease. Or something.

The tube itself is just some cheap steel tubing with a crummy paint job. I can see rust blisters forming under it.

I’m sure I can replace the leather gasket and get back to work with the pump, but having taken this thing apart I see there is nothing special about this at all. If I repainted the logo from “SILCA” to “XINRONG IRON MACHINERY WORKS FACTORY NO. 2″ you wouldn’t be surprised by this product.

Quality of life took a big jump up today — I cycle my Dahon to the office this morning. Only 16km but took something like 40minutes because of the number of traffic lights. I know a longer route that should be higher average speed, around 35km, that I’ll try later this week.

One direct way to measure quality of my life is to count how much I am able to ride my bicycle.   

I’m shagged. Got up with Luke at 6:30 AM, and after he dressed himself and played, I made Osso Bucco (it tastes better if it cooks, cools off, and reheats). The more languid the braising is, the better veal tastes. Then spent the rest of the day on bicycle matters.

In designing Matt’s Fourth Protocol, I was considering the results of Le Chacal. This led me to I spend a fair bit of the day doing measurements on Le Chacal trying to figure out why it handled squirrely on my bike tour in Taiwan. I started out thinking it was due to some fine measurements, but my working theory now is simply a matter of bad weight distribution. (I had too much weight on the back, and the front wasn’t loaded)

Then I finished assembling the Le Chacal. I was being quite anal about tuning the transmission system. Last week I screwed around for an hour perfecting the Z/L (smallest back and smallest front cogs) shift combo. The shifting is in good shape now.

Wish I could say the same thing about the brakes. The Braking system is still driving me up the wall, but that’s not the brakes’ fault. It’s the stupid wide rims I have on the bike. I need to get those replaced with narrower, lighter wheels pronto. There is barely clearance, and if I hit any mud, it jams the faces of the brake pads.

Headsets are a touch loose on both Le Chacal and my Dahon. I need to tighten them. Need to study how in my Barnett’s Guide.

I installed a set of “trekking” handlebars. This will give me more riding positions on long rides, hopefully avoiding wrist numbess and sore back. The old mountain bar was 250g, this is about 500g, but I think it’s an ok tradeoff. Plus, I’ll save more than that much when I replace those damn rims. I need to screw with the stem. Lower it a bit, or farther forward, or something. My friend is a professional Pilates instructor and bike racer. I’ll get recuit him to fix my positioning.

Ling even got in on things and started refurbishing her Paul Frank single-speed cruiser. The chroming was really, really cheap and blistered and rusted. So we took off those bits of hardware. Ling sanded things and I ran other things on the wire wheel. Next week we’ll repaint those parts with some rust-retardant, install the side-view mirrors she’s so insistent on, and then she’ll have a local errand bike.

Dropped the heavy Kenda tires and put a Schwalbe Marathon Racer on the back and a Continental Contact on the front, just for something different. I went out on a testing and calibration ride. I hit a field that was basically grass and lumpy, very wet clay. I managed to spin my way through without spilling over. So although there isn’t much tread on these things, I got the minimum traction I needed. (being able to stand up and crank w/ the trekking bars was also helpful)

I discovered the wooden workbench I dragged home yesterday was termite-ridden, so I beat it apart with a ball-peen hammer and crowbar then tossed the bits in the garbage.

Now I’m basking in my downstairs workshop, sipping a beer, and waiting for my osso bucco to heat up. It was so nice this morning having that massive Le Crusset dutch oven. I could brown all four veal pieces simultaneously, then sweat out the vegetables, plug it up with a cartouche, and let it braise for 2.5 hours. It’s nice having the right things at times. In an undersized pan, I could have never browned the meat nicely. (or at least concurrently)

After calculating Le Chacal’s weight at around 30lbs last night I tried to put it into perspective.

An ultracycling enthusiast said a bicycle weight should be no more than 12% of the rider’s weight. That means Le Chacal is built for a 250lb man. Or it’s 30% overbuilt. That’s his rule-of-thumb. What about the real world?

I found a nice list of actual bike weights for a range of bike styles and sizes. The bikes included long lists from Specialized and Giant (two respectable mass-market bike makers) as well as some more boutique brands. It covered a wide gamut of bicycles, from BMX to MTB to Road.

Le Chacal compared to a wide gamut of models, manufacturers, and styles

With this, I realized Le Chacal weighs the same as an average mountain bike. Right around thirty pounds. Road bikes are closer to nineteen pounds. Le Chacal also compares favorably to all-purpose hybrid bikes.

Le Chacal compared to the entire line of bikes built by Specialized

I feel a bit better having done this analysis. It shows that Le Chacal is not a piggish bike, compares reasonably well to MTB’s and Hybrids, to which it’s most similar, and by trimming a few pounds off from wheels and components, I actually move Le Chacal to the more competitive side of the weight spectrum in MTB and Hybrid classes.

Manufacturer’s average weights by class

Distribution of weights inside classes of bikes

I don’t know what I was expecting when I did a weight analysis of Le Chacal. That didn’t stop me from being surprised that my two wheels account for a full one-third of the total 13.84kg (roughly 30lbs) bicycle.

I’m glad to discover this, because I have known all along that my wheels are overbuilt. The rims are wide and heavily spoked, meant for a BMX bike, and the Kenda tires are pretty chunky, too. So cutting the weight with lighter wheels should make a good relative contribution to the bike. A ten percent savings here would amount to around 400 grams (nearly a pound) or a total 3% weight reduction.

Where can I make other savings? There is nothing I can do about the seat tube+cranks. I’m not sure how much the seat tube weighs versus the crank, but it’s probably 95% crankset, 5% seat tube. The crankset is a high-end Shimano set, so that’s about as good as it’ll be.

There’s no savings in the Fork/Headset either, unless I were to replace the steel blade fork with a carbon fork. Maybe I should consider that. Any meaningful savings from a different headset?

The seat stay and chain stay are made from fork blades. Consequently they’re pretty heavy. There’s nothing to do about it now, but I should think about this for Matt’s bike, The Fourth Protocol. Longer term, maybe I could try out carbon seat stays. Sulaiman suggested that we can probably use lighter tubeset overall.

There’s not much left than incremental savings on some of the components. The Pannier rack is heavy and nothing special. Perhaps I can hack that down or find an alternative. The seat is a stock Bontrager MTB seat. Nothing special and not especially nice for touring anyway. Maybe I’ll loot the fizik seat from my road bike.

Relative weights

This bike will never be a feather, nor need it be. I can probably save some weight and rolling resistance with some lighter wheels and maybe trimming a bit here and there. But, as Alton Brown likes to say, “a pint’s a pound the world around.” Filling up my water bottle can counteract my expensive component upgrades. At the end of the day, this is touring bike, not a racer, so it doesn’t matter so much.

Le Chacal originally had its rear brakes mounted underneath the chainstay. This proved problematic. The tolerances were too fine. The brakes barely fit properly to the rim, and the caliper arm was mere millimeters from the plane of the crank. It was an adjustment headache and a situation bound for catastrophe where crank + caliper collide.

Why didn’t I originally mount the brakes to the seat stay, like most bikes? The shafts of the brake braze-ons should be 180mm apart. The seatstay’s blades are too wide. Backed into a corner, I had to figure out a way to extend the brazeons closer to the center of the bicycle, so I could get to 180mm.

Seatstay

We cut some cmall bits of tubing, chopped them into a C-shape, and brazed the seatstay blade/C/braze-on simultaneously. It worked out well. We made a solid clamp to hold the pieces together and I got everything a uniform, bright red. The brass flowed evenly and smoothly. The backside had a bit of metal to be filed away because the clamping wire caused a touch of capillary action to pull the brass, but it wasn’t too bad and isn’t visible.

Flow, my brass, the policeman said.

So everything is sorted here. Sulaiman will repaint and I should be ready for the Taipei Bike Show #tcs next week.

Glad to be getting out of here.

Bike packed up quite easily. Seemed to have crammed it a bit tighter this time. Weighs in at close to 35 pounds if i have it really crammed with rubbish. Closer to thirty if it’s only bike-stuff. The helmet is the biggest nuisance to pack. The suitcase closes up very nicely sans helmet. But I have to do more fidgeting and jamming if I include the helmet. For obvious reasons I’m not thrilled to be mashing my suitcase when I know my helmet is pinned in there.

Hmmmmmmmmmmmm Just remembered…. where the hell are my saddle bags?! Better go find those.

Omani Border post. Waiting for John Rambo to arrive with Bazooka.

5% 10%? Even downhill was brisk

Tiny panorama

click here to download the Quicktime VR panorama

Setting up a high tension tower

I couldn’t make out exactly what was happening. It looked like they were cinching up the cables between 2ndRecent and 3rdRecent. This was the second-to-most-recent tower. The most recent tower, with massive temporary anchor cables, was still unpainted. There was a terrible amount of yelling and carrying on. I’m not sure exactly what the process was. I didn’t see anyone/anything at the third-most-recent tower either. It appears cable-pulling duty was provided by the backhoe below. Indian men were pushing around giant block-and-tackle pulleys that look as big as a small washing machine. I took short video but it doesn’t help to explain much either.

All-in-all it was a very pleasant four hour ride. I should have liked to do the full ride into Oman, I had the legs and planning for it, but oh well.

Le Chacal rides. After a heroic wheel-building effort from Sulaiman, we finished assembling Le Chacal today at 7pm. I report that it rides extremely well. It feels solid and similar to my Specialized Stumpjumper mountain bike. I am very happy with it. Tomorrow I will attempt to disassemble and pack it into a small suitcase. I leave for Liberation Day parade on Tuesday.

I need to stage a better photograph later.

When I get some more time, and after I’ve made revisions to the bike, I’ll do a proper neutral background picture of the bike. In the meantime, in my excitement, this is the best I have. Notice the over-long stem. The extender is too long. To compensate, I flipped the stem upside down. Looks weird, but the handlebars are in a good position relative to the seat. It’s a bit daunting riding the bike, because it feels like there is a 4″ long spike waiting to drive into my chest. Anyway, Sulaiman can machine off the end on Monday. I love the Kenda “urban trials free-riding” tires. They’re sort of urban BMX tires with a neutral, omni-directional tread. Not knobby enough to suck on the road, yet enough traction to ride on dirt roads.

Le Chacal

We tried to achieve a “gun blueing” effect on the frame, by tinting the clear laquer blue, but it’s not very apparent. Tomorrow I’ll have a chance to see it under sunlight, which brings out something of a violet tint. Can I blue my next frame like a firearm? Would that be more durable than a paint job? Sulaiman put heavy coats of laquer and top coat to hide the imperfections in my frame. It looks rich. I managed to drop a (heavy) part of my park bike stand on the top tube, taking some big dings out of the paint. Turns out that my roll of electrical tape is a very similar black, so I “touched up” the scar with that.

Chainstay. The matte part of the chainstay is actually several layers of electrical tape to guard against chainslap. Probably insufficient. I’ll have to do something better later.

This is a bit finicky part of the bike. The rear v-brakes cannot fit on the seatstay, as would be traditional, so we had to mount them on the chainstay. It’s not ideal, but it works. The tolerances are VERY tight, tryin to get the brakes andjusted, but to not come out far enough that the pedal hits them, etc. This is definitely not great part of the design. Fourth Protocol will have a different braking system for sure.

Seatstay

S&S Coupling

Got a surprising SMS today.

I didn’t expect this until saturday. Sulaiman has already machined out an extension that clamps on the steeering tub and extend up to the stem/handlebars. Turned on a lathe and cut for two clamps.

Wow! Sulaiman is going nuts. And I feel bad, because I know how many frames in his queue are waiting to be painted!

Today I booked my vacation to Taiwan. I’m going to the Taiwan International Cycle Show in March. Sulaiman and a few other friends are going. They’re going to bicycle around Taiwan for another week thereafter. I’m going to join them for riding for a few days as well before heading home.

Once I get back from Dubai I’m going to have to help Sulaiman get his own Le Chacal finished for his Taiwan trip. I’m not sure what he’s going to call his bike, but I’m looking forward to helping out on it.

I gave my friend Sulaiman a minor heart-attack today when I mentioned that I was leaving for Dubai next Tuesday. How in the world are we supposed to finish the bike in time for me to take it. Remaining: wheel building, painting, stem fabrication, and assembly. After some deliberation, we decided if we only primered the frame, that would leave enough time to finish it up for my Tuesday flight. I’ll properly paint it when I return in February.

I spent a few hours at the Rebound Centre today working on frame prep. We reamed out and faced the head tube and the seat tube. Brazing warps the tubes, so with a very precise reamer, we scrape it back to round. I did bunch of filet filing and took the rest of the lot home to polish up and tape the S&S couplings. Next week Sulaiman will sandblast, primer, and paint the rest of the frame. The fork is already painted, but not top-coated.

My big problem now is finding rims for my bike. I need high quality, 32-spoke, 20″ rims preferably about 26mm wide. Bike shops haven’t had them here and the BMX specialist only had 36 and 42-spoke wheels (way overkill). Ugh. I need them quick. I may need to airlift them from the USA.

When I came home I used my dremel tool to cheat and polish up the s&s couplings. Luke saw and wanted to join in. So we played with the dremel tool and afterwards he decided he wanted to drill (his favorite craft).

Luke and Mona then went on to play chase and tug-of-war until they were both absolutely exhausted.

Ling, Emily, Luke, and Ling’s mom are in Klang visiting their family. I’ve spent all weekend working on my bike.

It’s getting close to the end, and it’s getting to all the sort of shit I hate doing. I feel like I’m in Vo-tech Autobody Class now…. filing brass, sanding rust, cleaning up the finish. Stuff I’m neither inclined to enjoy nor inclined to do a good job with. Anyway, the fork is primered, as are two straight segments of down and seat tubes. The remaining pieces still need more cleanup to smooth out the filet welds.

Boy, lesson learned. “touchups” of brazes suck. Far, far better to do it all correct and complete the first time. Do it right, like I did on a job today, and the resulting work is so smooth and nice, it barely needs sanding. Do it wrong, and you get boiled-off brass, bubbles, lumps, excessive filing, etc. Major mistake? don’t get the piece(s) uniformly cherry red. Most of my problem came from applying brass before everything was critically hot.

Anyway, I’d say by this time next week I should have a totally primered frame. I’m working on a small headbadge. My main issue now is getting hold of a good quality wheel-set for the bike. The rest of it I’ll assemble with ubiquitous Shimano components. I need to make a stem too, but I can do that later.

I took a day off today to settle a bunch of errands in the morning and then spent the afternoon at Rebound Centre working on Le Chacal.

I silver-soldered the “braze on” fittings– water bottle screw mounts, pannier mounts, and cable guides.

I tried to touch up some missing brass on an earlier braze but didn’t build enough of a fillet and I’ll still have to build it up further.

The silver-soldered stuff went on mostly ok except for one I flubbed, blackening the metal. When the joint is polluted with oxidation, the silver won’t flow until I clean it up.

I didn’t mess with the two sets of brake mounts yet. They’re a bit more fidgety to fit, measure, and mount. Plus, they need brazed with brass, not silver, and I managed to ruin the #2 oxy-acetylene tip I use for brass brazing. So tomorrow I need to run to the welding gas store and buy a new tip.

The bike is getting dangerously close to assembly. Finishing today’s work on Saturday will be an hour or so. Hopefully I can get the brake mounts finished in under two hours. With that done, we’re ready to prep the bike, facing the bottom bracket, etc. At that point I have a finished frame ready to paint.

I want to hustle and get this finished. Looks like I’ll have to be in Dubai for most of the second half of January. Yuck. A workweek there is bad enough, let alone a weekend. I think what I’ll do is take a weekend trip to Oman. It’s mountainous desert and should be considerably more interesting than Dubai. This will be a great chance to test out ho Le Chacal works in the field. What better place to do it than in the mountains of a medieval desert fiefdom.

Things I’d do differently for my next frame, The Fourth Protocol:

1. Before I do any work, I’ll primer the tubes. This will keep them from corroding from my sweaty hands (I cannot wear gloves — they drive me nuts) and will make marking measuring points far clearer. I can always sandblast that off and re-primer properly when ready to paint.
2. Label everything. “up down left right” etc. The would have saved me, for example, one wrecked set of dropouts and an afternoon.

Everything but the fork

Sulaiman was the hero of the day. After I made a totally pathetic effort to scallop one of the s&s fittings with the grinder, Sulaiman volunteered to grind the other THREE (ugh — that’s about 6 square inches of carefully ground-away metal) while I silver-soldered. It was telling that I couldn’t even distinguish the factory-scalloped fittings from those Sulaiman made. While my one’s “point” was a 5mm radius circle.

I am off Wednesday, so I should be able to make a very earnest run at finish this thing up to make it ready for painting and components. Sort of a weird that all the sudden it’s 80% done.

Returned to the Rebound Centre this (late) morning to work on Le Chacal. It’s the first time in something like three weekends. I felt rusty. Today’s job was to start installing the S&S couplings into the frame.

The S&S couplers take up 35mm of length in the tube. Step one is to chop out 35mm segments from the existing frame.

Before

I gave myself quite a scare (to the amusement of Michel and Sulaiman). After I made the cuts (which I checked and rechecked) and was dry-fitting the bike back together, I wanted to gag when I realized I had cut way more out of one piece of tubing than the other. How could I be so fucking stupid? I measured and double-checked my measurements repeatedly.

That’s when Michel helpfully pointed out that I had only made three cuts so far, not four. I had simply failed to finish cutting out the segment from the second tube before I left for lunch.

Much relief ensued when I realized I hadn’t shortened the frame. I just needed to make one more cut.

After

Since I was cutting up the frame, all sorts of surprises appeared from inside the tubing. I could see how well my braising penetrated (reasonably well, although later welds were clearly better). I also discovered where all our flux went.

In from Bogota

The rear triangle cuts are finished (yellow) and fitted into the jig. Tomorrow I’ll silver-solder them. The four other joints on the top and down tubes I’ll try to finish tomorrow too. Might be slowed a bit because some of the couplings need to have a decorative scallop carved into them first.

Yellow rear triangle; Blue tomorrow’s tubing

Sulaiman, cheering his victory after guessing the weight of my frame to the tenth of the pound!

I boastfully made a market of 7.5 at 9.0 lbs. I am glad I lost to Sulaiman’s 5.2lbs bet.

Today was the final brazing job — the seatstay. The brazing and setup wasn’t hard, but we had concern about our novel bolt-on seatstay/dropout interface. Especially fear of melting the silver solder (600c) while brass (900c) brazing nearby. Fortunately it was never a problem.

About the only issue was we ran out of Acetylene gas and bronze flux. We ran over to 5 Kallang Place for replacements and lunch.
Oh, that and I managed to burn myself three times being an idiot three times. Here are three brazing tips:

1. Don’t try to hold a hot brazing rod in your teeth while holding a torch with an 8″ lance of 1200C flame in one hand and try to move a 30lb bike jig around it’s Z axis. You tend to have the brazing rod lay across your arm.
2. Don’t touch the bottom of a piece of metal who’s top you’ve been heating to 900+ degrees for the last ten minutes.
3. Don’t try to hold a hot brazing rod in your teeth while holding a torch with an 8″ lance of 1200C flame in one hand and try to move a 30lb bike jig around it’s Z axis. You tend to have the brazing rod lay across your arm. [yes, very similar to tip #1]

Today’s final assembly

the bolt

Foppish Cap

Semi-finished frame

Next session

Pre-gluing for an embroidery project

Puttered around this weekend. Wasn’t especially memorable.

• RC Rockcrawling with Luke. First day I vibrated out a drive shaft set screw. (which I recall having Loc-tited!) Second day I popped a breakaway joint on the driveshaft while scrambling up some rock debris. Need to diagnose why the system spasms. Low voltage onboard power? RC Controller? or the radio is broken?
• Finished mitering the seatstay Saturday. It’ll be the final braze. I planned to go in on Sunday, but woke up late, and Luke wanted to play.
• Watched James Bond ‘Quantum of Solace’ last night. OK movie. Enjoyed the violence and the scenic shots of Italy and an Andean desert.
• Bought a large, square chopping board at IKEA to make a table top workbench for my ‘clean’ lab in the attic. I don’t want to ruin my antique marble coffee table by soldering over it. Also bought some IKEA plexiglass trays that are meant for kitchen storage but will be great for disassembling things with lots of miniature bits to fall off.
• Started working on a small bag project. Inspired by a bit of red felt I found.
• No great meals, although had a nice spinach salad Saturday night and some decent chicken burritos. The reason Matilda can cook pretty well is that she is not afraid of adding enough spice and, as I do, totally ignores volume instructions for spices and seasonings in cook books. It’s easy to double or treble the seasonings and the result is often substantially better.

seat stay custom connectors machined by Sulaiman

The process for brazing in the threaded inserts was interesting.

The insert was a short 1.5cm plug. So I pushed a plug of silver flux paste into each seatstay blade. Then clamped the stays vertically (with the openings I needed to braze pointing down to the ground). Then we made short coils of 48% silver flux rod and pushed them into the blade openings, followed by the inserts. Then we used some spokes to hold the inserts up in the stay blades. Silver melts faster than brass. The trick here was to get everything hot, and then get the walls of the seat stay hottest, so that when the silver melts (which happens suddenly), it follows the hot walls of the stay and runs down to the bottom.

It worked pretty much exactly like that. After some heating, suddenly silver appears a bit out of the edges, and that’s it. The braze looks pretty clean from the outside. One side bled a bit of silver on the wrong side and got solder on the threaded section of the insert, but we easily cleaned that out with an M8 tap.

Hunter: Was that you shooting?

Leary: Yes.

Hunter: That’s a cool gun you got there. Could I see it?

[Leary gives him the gun]

Hunter: Shit, that’s light! What’s it made of?

Leary: Composite. Like plastic.

Hunter: Mind if I give it a little dance?

[Leary shrugs. The hunter shoots a duck]

Hunter: That is great! That is really really great! You wouldn’t want to sell it would you?

Leary: No, I need it.

Hunter: For what?

Leary: To assassinate the president.

[Hunters laugh]

Hunter: Now what do you want to do that for, mister?

Leary: Why’d you kill that bird, asshole?

[proceeds to nonchalantly kill both of the hunters with his gun]

Today was my last day of Gardening Leave. I came into the workshop in time for lunch. Sulaiman and I discussed how to mount the seatstay to the rear dropouts. We settled on some kind of hinge. It was a sufficient idea, but not compelling.
Lunch wasn’t over, so we brainstormed alternatives for sport. The idea we liked best was to somehow plug the seatstay to the dropout and then tighten it down with a bolt.
We came back to the shop and made some drawings.

first rough sketch of the idea

working out the finer details

doing the arithmetic to mill the base plate

Both Sulaiman and I were excited by this design. It seemed cooler and less of a kludge than a hinge. In our excitement, we worked out the dimensions for the base plate, which Sulaiman milled and I fitted to the dropouts. This week Sulaiman with lathe-turn the flanges. On Saturday I’ll miter the seatstay blades onto the wishbone neck. Then we can start to silver solder the threading into the tubes and the flange onto the plate. There is a really clever way to silver solder this. We stick a ring of silver up on top of the thread block. Then we heat up the whole mass, the silver melts, flows and solders up the lot. That’s instead of trying to jam a rod of silver braze up there.
The dimensions should work. We chose M8 bolt because it is most likely to be field-replaceable if I lose it. It should be a fun finish to the design… some machine work, some interesting brazing, and some picky mitering. The end product could look pretty cool and definitely customized.

Today I efficiently mitered and brazed the chainstay to the bottom bracket. I only had three hours to spend today. I wrapped up and turned off the OxyAcetylene tanks rights at my 1pm curfew.

Today’s job

Sulaiman was very busy painting a litany of bicycles but when he saw my results said that my brazing had improved considerably. That was quite a high note to end on.

underneath the bottom bracket

Now the next step is to figure out how to attach hinged seatstays to the dropouts. After that’s finished, the frame is complete. Then I’ll proceed to cut it into seven pieces a reconnect with S&S couplings.

Sulaiman lent me the dated, but interesting, http://www.amazon.com/Designing-Building-Your-Own-Frameset/dp/0960241833.

Just starting to read it now. Seems to emphasize lugged frames. Hopefully it can help me improve my brazing chops and give me some accuracy tips.