A Father-Daughter Build Thread

[cblandford]

Finishing the fork:

...
3. Rake blades
4. Tab dropouts; slot fork blades
5. Braze dropouts to blades
6. Finish blade ends
7. Braze blades to crown
9. Finish crown
10. Machine race seat


Time to get the fork blades ready. For this bike, I decided to use a pair of oval chainstays as fork blades. The oval of the chainstays wasn’t the same as the crown’s sockets, however, so I had to nudge the oval-ends of the chainstays in my vise. I also used pliers and a small tack hammer to umm… smith?... the crown a bit. It was a tad loose in spots; a few taps and nudges here and there got everything fitting nicely. Again, going for that snug slip fit, just like the steerer/crown.







Once they fit well, I rake fork blades on my Hammill bender. Here, I used my 5” radius die, to match the radius on the seatstays. I use my eyes to keep the oval vertical. I tend to rake in two or three nudges, comparing to my drawing between each nudge, sneaking up on the correct amount of rake. Once the first blade is good, I set a surface gauge to indicate to where the next blade should be raked. Then I (carefully!) rake the second blade to match.









Once raked, I compare to my drawing and trim both ends of each blade. As with the chainstays, there’s a bit of a balancing act here to make sure the blades, the curve of the rake, and the dropouts end up as intended.

Next I put a tab on the dropouts, as described previously when I made the chainstay sub-assemblies. Once tabbed, I load the dropouts into the jig, slide the blades into place, hold the tops of the blades with the crown/steerer assembly, and use a straightedge to scribe a “front” line onto the blades. Then I measure the dropout/blade angle, and slot the blade. If everything goes well, I have a tight fitting slot/dropout and also no twist in the blade that would mess with the crown fit up. All good this time around.















Next I dress the ends of the blades, clean everything up with 80-grit and isopropyl, (bronze) braze the dropouts to the blades, soak, and finish off the ends.












Once the blade/dropout sub-assemblies are complete, I check their length. I do this as shown, first using a crown (I had an extra of the same model lying around) with a steerer inserted and comparing its center to a wheel’s rim. I also use my workbench’s “corner” and some blocks to compare against one another. I adjust the blade length (if needed) and square up the ends on my belt sander.







Finally, I drill vent holes in the tops and bottoms of the blades, clean everything with 80-grit (especially the insides of the crown sockets) and isopropyl, then flux and (silver) braze the blades into the crown sockets. This is done in the jig. As with the steerer, I fill these things up, to the detriment of my “shorelines”. Someday.













Cool and soak.

To finish the fork, I use files to remove the casting marks and the little brazing-helper nubs on the crown. Then I machine the crown race seat with my Park tool cutter.









And that’s that. For what it’s worth (nothing), I love making forks (and stems, for that matter). They’re relatively easy to make and really fun to braze and finish. It’s a bummer that so few pro builders can justify the end result--or the time spent--to their customers. If all I was building for these bikes were the “frames”, I’d feel like I was doing way less than I could (or should). In fact, I’d love to eventually learn how to make other parts… cranks, brakes, seat posts, bars, etc. Why not?

Speaking of, time to figure out the brakes! Back soon.

-Chris

[cblandford]

All right, BRAKES!


…
20. BRAKES!
…


I’ve decided to go ahead and put hand brakes on this bike, as originally planned. I went back and forth a bit, but I think this is the right decision. I can always add a coaster brake if need be; it’d be tougher to go the other direction.

Brake bosses, I’ve found, are straightforward. Here I’m using a Paul brake (see Nerd Note A). For any Paul rim brake, I’ve used the simple, spring-hole-less Paragon bosses. To get them located, I install them onto the brake arm itself, insert a wheel into the frame (see Nerd Note B), and place them on the frame/fork. I mark the location with a Sharpie and that’s that. I usually check my placement against the recommended distance-from-axle spec, but--imagine that--the spec for brake stud distance for a 305 BSD rim isn’t listed in any of the obvious places.









Next I cut down and miter the studs to fit the fork blades/seat stays. I’m sure that there’s a good reason most cantilever brake bosses sit so far off of frames. Because I don’t know what it is, however (and stuff like that drives me crazy) I can plead bicycle-ignorance and do what I want. I cut these down to a size that makes sense to me, so that the brake arms sit as close to the blades/stays as possible. I miter the bosses so that, once attached, they’ll sit ~80mm apart. I wouldn’t want to do any of this without the actual parts on hand.

One note: on this bike I’m running the rear brake on the underside of the seat stays. The swoop of those stays provides enough clearance (from the chain) to allow for this, and I think it looks nice. Almost like I was planning to do this all along. For the record, I was not.

Once mitered, I load these into my brake boss jig (from Nova), double check everything, and drill small breather holes in the seat stays and fork blades. Then I clean, flux, and braze them on (see Nerd Note C). I use 1/16th bronze rod and my 203 tip for these, just like dropouts.













Double check by installing the brake arms, soak, and finish the little fillets. All good.

Next up: final braze-ons.

-Chris



Nerd Note A: I installed a pair of Paul Minimoto v-brakes onto the little Cleary bike and let Mathilda have a go at giving them a good squeeze. I’m actually really surprised at how much force she can get on them with the little Tektro teeny-reach brake levers. When combined with the adjustable Paul spring, I think I’ve got a winning setup here.

Nerd Note B: Since this frame uses track dropouts, I installed the drivetrain while locating the rear bosses. The rear axle is going to end up sitting about dead center in the dropout, which I feel good about for multiple reasons, but especially in consideration of the boss placement.

Nerd Note C: I brazed the rear studs on with Filletpro silver flux and rod. I noticed while cleaning the four studs up that one of them looked extra shiny. Sure enough, when tested with a magnet, one of the four was stainless. Not sure how that happened (I must’ve ordered a pair of stainless bosses a while back?), but I’m glad I caught it. Rather than re-miter another stud, I just used the Filletpro. The fork studs I brazed on with bronze.

[Thomas Norton]

Chris, great post! I am at Doug Fattic's for my final week and Cantilever posts are scheduled for tomorrow. I like the idea of shortening the post . But the Paul Touring Cantilever come with KoolStop pads and Pau recommended I shorten the length so they don't hit the fork blades. If I shorten the post I will have to shorten the pads that much more . So we will see tomorrow!

[Andrew R Stewart]

Tom- I have done the opposite, I've lengthened the canti post base on many of my builds. To both better clear the long pads common today as well as have more base/frame overlap. Andy

[Thomas Norton]

Andy, we will see if the Paragon ones with the least amount of mitering will be long enough.

[cblandford]

...I like the idea of shortening the post . But the Paul Touring Cantilever come with KoolStop pads and Pau recommended I shorten the length so they don't hit the fork blades...

...I've lengthened the canti post base on many of my builds. To both better clear the long pads common today as well as have more base/frame overlap...

Aha! That makes sense, and seems obvious now that you pointed it out. The KoolStop "Thinline" pads are all I've used on bikes that I've made for myself. They're pretty long. Or, they're long enough that when mocking up brakes I haven't even considered trying to clear them from fork blades when open. I also rarely remove wheels from frames (unless a tire is flat), so I've never paid much attention to that issue. Thanks for the insight!

Thankfully, I'll be the sole mechanic for this bike... Nobody to curse at but myself.

-Chris

[cblandford]

Getting closer.

…
21. Cable Routing
…


Now that I have the rear brake mounted, I can determine how I want to run its cable. I begin by installing some handlebars, and cutting a piece of housing. I hold the housing up to the frame, play with it until I’m satisfied with the run, and make marks with a Sharpie. For this bike, I decided to run the cable internally, in full-length housing. It will run from the bars, around the non-drive side of the head tube, and into the underside of the drive-side top tube. It will make its tube-exit in a spot that I hope minimizes how far out the v-brake noodle will protrude.







I understand that most (proper?) internally-run cable housing runs through a brazed-in brass or stainless tube (and is done up front, before any tubes are connected together). I decided here, however, to merely braze on a little reinforcement plate and drill an angled hole for the cable. (This is similar to how I’ve internally-routed lighting wire in the past.) I’ll probably do something different on the Father bike--we’ll see.

I cut out, cleaned up, and (silver) brazed on the reinforcements. Then I drilled a hole in the tubes, and used files to enlarge and angle the holes for the housing. Once done, I test fit the cable. Upon doing so, I found that the cable bends were a little sharp entering and exiting the tube. I pulled the housing and “flattened out” (?) the holes a bit more. All good. The brake pulls pretty nicely, I think.













I thought I was just about done with this bike. While working on these bits, however, I decided that I wasn’t going to be happy with any short, off-the-shelf, 1” threadless stem (if I could find one at all). I've decided to go ahead and make a stem.

So, next up: make a stem.

-Chris

[Andrew R Stewart]

Oh I was so into this build thread till you went internal... :)

Joke over, for a kids bike not a bad way if done well. Andy.

[Colinmclelland]

This has been awesome to track. Promise me when she outgrows it you'll try to find someone else deserving! It's been such an awesome project, I'm almost looking forward to her outgrowing it so we can see part 2.

[cblandford]

Oh I was so into this build thread till you went internal... :)

Yah, yah, I know. I've never done it before, but it made sense--to me--to do it here. It was a bit of an afterthought, but I think it turned out ok. Clean looking, anyway.

This has been awesome to track. Promise me when she outgrows it you'll try to find someone else deserving! It's been such an awesome project, I'm almost looking forward to her outgrowing it so we can see part 2.

Cool - thanks! I'm sure she'll outgrow it in a flash. The balance bike I made her went from being tippy-toes-too-big to haunched-over-way-too-small in under two years. Hopefully this one lasts that long. I'll be curious what we decide to do with her balance bike once she's able to ride this one, too... Heirlooms are fun and all, but something tells me she'll want to pass it on to someone younger than her. I'll make sure to update this spot when this new bike inevitably gets replaced.

-Chris

[Colinmclelland]

...Heirlooms are fun and all, but something tells me she'll want to pass it on to someone younger than her. I'll make sure to update this spot when this new bike inevitably gets replaced.

-Chris

As Elliot Goblet used to say "You can't have everything...where would you put it?"

[Thomas Norton]

Colin, after fitting up the Cantilever posts it was evident that the pads will need to be cut down in length. Apparently they is a way, using a slip tube setup, to increase the height off the fork blades. But as a newbie just learning I need to simplify!
We got the chainstays on yesterday and today the seatstays! I am having a great time!

[cblandford]

Stem:

1. Miter Stem Pieces
2. Tack and Braze Stem
3. Finish Fillets
4. Braze Binders
5. Slot and Relieve Binders


I’ve only made a couple of stems like this one previously, but the process has been straightforward.

I begin by designing the stem in BikeCAD, printing the miter templates, and mitering the stem’s main tube. This tube is, essentially, a very short downtube; I miter it exactly as described previously. The other tubes (both made out of .058” tubing) are cut to length and squared up on my belt sander. I leave the tube that clamps onto the steerer long so that I can grab it while brazing. I’ll trim it to length once the binders are brazed on.







Once mitered, I drill vent holes in the clamping tubes, clean, flux, and load the tubes into a stem jig (Sputnik). I tack the stem together in the jig (obtuse angle first, as before), let cool, then pull the stem from the fixture. To braze, I clamp the stem onto a longer length of tubing.

Braze, let cool, and then soak.







Next I finish the areas of the fillets closest to where the binders will land. Then I miter and notch the binders (just like I did with the seat tube binder), clean, flux, and (bronze) braze them on. Soak once more. Finally, I drill a pucker hole in the steerer-clamping tube and slot both binders with a hacksaw and flat files. I also file a little half-round relief in the binders where they pinch together. At last I trim everything to length and finish any remaining fillets. I also shape the handlebar clamping tube a bit, to make sure that the handlebars’ curves--when installed--run through easily.













The final thing I did for this stem was run a flex-hone (chucked up in my cordless drill) through both clamping tubes. Then I installed the stem and handlebars and checked that all went according to plan. All good this time around.







(This reminds me… I’m not sure if I mentioned before: a seatpost of the correct diameter fit nicely into this bike’s frame, which I checked back when I was finishing off that binder/slot. I didn’t bother reaming the seat tube on this bike. There, too, I merely used a flex-hone to finish it off.)

Next up: final touches and off to paint!

-Chris

[Ras72]

I know paint is necessary but it's a shame to cover that beautiful work.

[cblandford]

I know paint is necessary but it's a shame to cover that beautiful work.

Necessary, and half of the fun! I don't feel like a frame is finished until it's covered with color... The raw looks don't do much for me. I appreciate the compliment, though!

-Chris

[shirk]

Beautiful work.

[cblandford]

Beautiful work.

Thanks!

[cblandford]

All right, let’s get this little frame off to paint. To finish up:

…
22. Make and braze-on headbadge
23. Fill pin-holes (if needed)
24. Drill BB vent hole
25. Final soak and clean up
…


I designed this headbadge, primarily, so that it’d be easy to make and braze on. I cut these out of regular, .058” tubing (the same used for the head tube rings). I print the logo onto sticker paper, cut it out, and stick it to the tube. Cutting wheel, then small files.











(Those first couple photos were from a previous project, but that's the idea.) Clean, flux, and (silver) braze. I’ve just lined these up by eye. No pins or special fixtures.

Next, I go over the frame and find any pin holes that need filling. I only started doing this recently, after I listened to an interview with Rudi from Black Magic Paint. The last person I want to think poorly of my bicycles is the person tasked with painting them.

I fill any pin holes larger than the head of my smallest drill bit. I drill them out, flush with isopropyl, flux, dollop on a bit of silver, and sand smooth. On this frame, I filled two holes--one on the dropout and one on the stem.







Finally, I give the frame, fork, and stem one last soak in my ultrasonic cleaner. Then I remove the pieces and go over each with red Scotchbrite. The metal turns rich and dark while soaking. Bringing it back to shiny forces me to look at each spot of the frame and make sure I’m not forgetting anything. I know this isn’t necessary, but I like handing off decently clean parts to the painter.









That’s it. Off to paint. I dropped this off at Black Magic last week.

Next: I'll share the paint scheme, get any needed parts ordered, and--finally--start in on the Father frame.

-Chris

[Thomas Norton]

Chris,so you don't sandblast the frame before painting? You mention ultra sonic cleaner. How big is it?

[cblandford]

Chris,so you don't sandblast the frame before painting? You mention ultra sonic cleaner. How big is it?

Thomas - I'm not painting the bike, unfortunately! The painter will do all the actual paint prep which includes blasting. I just like to hand off a clean-ish frame. My ultrasonic is pretty small (maybe 2x1x1?)... I have to rotate a full-size frame a couple of times to hit every spot. It's not necessary at all, but I like how quickly it heats up and blasts off used flux. I also use it to clean chains and such. Pretty nice.

-Chris