Lugwork - 3

One final lug to work - I'd cut triangles in the seatlug previously, but had to wait until I could see how the seat stays would attach before doing the back. I mitred one of the seat stays last night and simply traced around the end. At first I thought some triangle cutouts in the long tangs would look good, but decided they were too fussy, so simply cut the tangs down and reshaped the back a little.



Here's the result.

More progress on number five.

I'm making good progress on putting Ben's frame together. Here's a photo of the front triangle and chainstays in the jig. The XL tube sizes are a tight fit, but it all goes in okay. The top tube isn't brazed in yet - it's just jigged up so I can mitre the seat stays and work out what to do with the skirt section on the seat lug.



Here's a nice macro photo of the lower head lug. I used 56% silver filler with this, and dropped back to a number 12 tip, using the system 48 flux. I'm quite pleased with how it turned out - the amount of filler is good, and I got full penetration without much encouragement. Also shown is one of the ergo cable adjusters. These are quite a challenge to hold on the downtube. These were brazed in with 56% silver filler, using the stainless light flux.



Here's the progress on the bottom bracket. As you can see, I'm yet to mitre or braze in the chainstays. The BB-downtube join was done with system 48 filler, and system 48 flux. I went up to a number 20 tip for this one (I modified my largest acetylene tip for LPG by drilling a counterbore in the end). I really liked using this tip - it let me get very even heating.

The system 48 filler is a little gummier than 56%. I don't get the minimalist shoreline fillets I'm used to with 56%, so there's a little more shoreline cleanup needed. That said, it pulls through really well and fills bigger gaps than 56%. Just the ticket for bottom brackets. I can see myself using quite a lot of this filler.



Finally one of the dropouts. I've got a standard recipe now that works a treat for stainless. 56% filler with grey stainless light flux. I used a number 12 tip here, as the dropout tends to act as a bit of a heatsink. I overdid the filler a little, as evidenced by the excessive fillet in the cutout. Contrast that with the really nice fillet I got on the cutouts on the lower head lug.

Interior cable routing

Interior cable routing is quite a bit of work, but very rewarding when it works well. I use a two-step process, where I first solder the tunnel to the top tube, and then solder a reinforcement piece over the top. It makes for a lot of work, but I think the peace of mind knowing that the join is nice and solid inside is worth it.

I start by slotting the top tube - I just use a drill and file for this - I aim to get a really neat fit to the angled cable tunnel end. Then I assemble the cable tunnel by cutting the middle piece to length, and soldering the larger end pieces on with 56 % silver.



Next the cable tunnel is inserted into the tube. This can be tricky. Ben's frame has the entry point horizontal on the right side, to make for neat cable routing around the head tube, and then horizontal again on the left at the back. I'm leery of having the cable exit at the top, as that's asking for water to work it's way in.



Apply plenty of flux (I'm using the System 48 flux here, with 56 % silver filler).



And solder the tunnel to the tube, aiming for a small fillet all around.



After cleanup, it looks nice and clean, with a good fillet.



Next, I put the reinforcing diamond on top, ensuring it fits neatly. A little bit of blacksmithing was required to form the diamond so that it neatly fits the 31.75mm XL tube, as they're designed to go on 28.6mm tubes. I forgot to take a photo before fluxing, so the fluxed one will have to do.



And solder it in, again using 56% silver filler and System 48 flux. It's hard to do these neatly, as you have to ensure there's enough filler to fillet the tunnel end, and it tends to go everywhere. Also they're tiny pieces, and easy to overheat. I use a much smaller tip (no. 8) than my usual no. 15 for this work.



Finally, wash the flux off, cut the tunnel down neatly and use emery and needle files to remove the excess filler.

System 48

I wasn't 100 percent happy with the fit-up of the seat tube socket on the bottom bracket of Ben's bike. The casting was just a bit more sloppy than what I'm used to using with 56% silver.

The issue here is that 56% silver is not at all forgiving of gaps. It flows like water (which is a good thing, as I can get really good penetration when everything is just so), but has practically no ability to fill.

So I asked for advice on the framebuilder's list, and was pointed in the direction of System 48 filler and flux, by Wade Barocsi of Cycle Designs. This stuff is still a silver filler, but is formulated so it's got an ability to fill a little. Like 56%, it's revoltingly expensive. I do wish people wouldn't speculate on silver and push the prices up.

In use it's clearly more viscous than 56%. You've gotta give it encouragement to draw it through the lug. It does though, and the result is really strong, without having to go to higher temperature fillers like LFB. The cable guide on the other side is held on with 56%, and I didn't reflow this join.

The picture shows the result, immediately after soaking the flux off and prior to any clean-up, so it still looks ghastly. You can see it's penetrated 100%, and also that I was a little on the generous side.

Another thing you can see here are pins. I pinned this join, and soldered it out of the jig. I'm quite happy with the result - it's a hell of a lot easier to get access.

Lugwork - 2

I thought I'd show the process of putting a cutout in a lug.

The lug I'm working on here is the upper head lug for Ben's bike. It's a Llewellyn Cadenzia XLH lug, and I'm doing a little work to it to make it look more like a classic Bocama Professional.

I start by roughly marking where the cutout will be, using a sharpie. Then I put four center punch marks in; one in a little from each of the triangle vertexes, and a third right in the middle.

Next I use a pillar drill to drill a 1/8" hole where each vertex will be, and then a bigger hole in the middle, as shown below:



Next step is to open out the holes to form a rounded triangle. I predominantly use a 1/8" diameter Swiss No. 2 round file to move the vertex around, and a three square Swiss No. 2 file to bring the sides down towards the vertexes:



Once I'm reasonably happy with the shape, I swap to needle files. These are mainly used to reduce the diameter of the vertexes and smooth everything up:



These cutouts have a matching one on the other side, so I do them both at the same time, doing plenty of measuring to ensure they match. The final step with this lug is to round out the cheeks a little to soften the look. Here's how it ends up looking along with the lower head lug, which I did previously:

Lugwork

I confess this is probably my favorite part of framebuilding; where I get to play around with the lugs and make them look right.

I started by quickly filing and sanding the casting roughness from the derailleur tab and STI cable bosses. There wasn't any real modification done to these, save to file the loveheart cutout on the STI bosses into a rounded triangle, so that it matches the other lug cutouts I plan for the frame.

Next I removed the rack mounts from the dropouts, and cut some small triangles into them. As with the other stainless parts, much of the casting roughness has been files off and I've hit them with some emery. Once they're on the chainstays, I'll do some more serious sanding and polishing.

Finally I went to work on the lower head lug. I first cut a triangular cutout in the tang, and then removed the cast-in STI bosses. They looked a little full then, so I cut more triangles in where the STI bosses had been, and rounded the sides a little. I'm quite happy with the look now.

Next step is to replicate the cutouts and shaping on the upper head lug, and then decide what I want to do with the seat lug.

Ingredients

Here's the ingredients that I'll use to make Ben's frame (from the top of the picture):

• Head tube: Columbus 36mm.
  
• Down tube: Columbus Life 34.9mm x 650mm
  
• Top tube: Columbus Life 31.7mm x 600mm
  
• Seat tube: Columbus Life 31.7mm x 635mm
  
• Seat stays: Columbus Life 17mm, tapering to 12.5mm tips.
  
• Chain stays: Columbus Life 30mm x 17mm oval, tapering to 12.5mm tips.
  
• Brake bridge: Silva art 189 with art 362 reinforcement diamonds.
  
• Dropouts: Llewellyn LRD72/SS stainless, 72 degree angle.
  
• Front derailleur tab: Silva art S286 stainless.
  
• BB cable guide: W2081 stainless.
  
• Bottom bracket: Long Shen LB09-3
  
• Lugs: Llewellyn Cadenzia XLH.
  
• STI bosses: Llewellyn LL-09-35 with Ceeway brass deluxe STI adjuster screws.
  
• Brake cable tunnel: Silva art 150 with art 141 reinforcement diamonds.
  
• Rear derailleur cable boss: Silva art 152.
  
• Bottle bosses: Silva art 471 with art 361 reinforcement diamonds.
  

Not shown, of course, are the 56% silver rod that I'll use to braze the frame together, nor the paint.

Next step is to do some lug prep - I'm going to cut the STI bosses off the lower head lug, and cut triangles in many of the lugs, to give them a classic Bocama look - something like this:



Then I'll file and sand the casting marks out of the dropouts, front derailleur tab, and STI cable bosses in preparation for polishing once they're brazed in place.

Only then will I start cutting and mitering tubes.

Decals continued

My first lot of decals have arrived, from Cyclomondo.

I'm quite happy with them - the Gerber printer does quite a nice job. They aren't strictly speaking decals, but instead are printed vinyl stickers, similar to the Columbus etc ones. They're certainly thin enough to be hidden under clear coat.

The hardest part was finding a file format that Greg could read reliably - the software I used to create the artwork (Inkscape) doesn't output the right files for the Gerber printer, so lots of experimentation was required. I ended up sending Greg .eps and .plt (hpgl) files, one of which he was able to work with.

Greg removed some of the black outlining from the head badge - presumably to ensure that it printed well, as the outlining was pretty thin. I put it back with some fine 0.03mm Copic markers :) I confess I quite like hand drawing parts of my decals - fits in with the whole Richard Sachs "imperfection is perfection" thing, and allows me to release my inner artiste.

I think I'll scale up the downtube decals a bit for the next go, as these ones look a little small even on Kristyn's titchy frame.

Number Five

So construction has started on number five. This is a road racing frame for a friend, Ben. It'll be a 57cm square design, with short 41cm chain stays and a 73 degree seat tube angle. The 72.5 degree head tube and 45mm fork rake will make for a reasonably fast handling bike without being a handful - just the thing for road racing.

Ben wants a nice, stiff bike, so we decided to build with XL tubes - that means a 31.7mm seat tube and top tube, with a 35mm downtube and 36mm head tube. It'll be compatible with 1 1/8" steerers, so getting a fork that fits should be a doddle. I confess I have my doubts about the aesthetics of XL tubes. I prefer the slightly more traditional look of OS tubes myself (28.6mm seat and top, 31.7mm head and down). That said, in a 57cm bike, the XL tubes probably won't look too out of proportion.

Tubeset is Columbus Life, courtesy of Peter at Ceeway. The butt lengths work out quite well for lugs, on account of the frame being a little larger than average. I'm building with Llewellyn Cadenzia XLH lugs, which have a nice classic Bocama style shape. I'll probably do a little lug carving on this one, to make them look just a little skimpier.



Ben uses Shimano parts, so I'll cut the STI bosses off the lower head lug and attach some Llewellyn ones to the downtube.

I really loved using the Llewellyn stainless dropouts last time, so will use the same ones (in a 72 degree angle) for this frame.

I bought some Sachs front derailleur bosses as well, but it looks like (unlike the Silva parts I've used previously, which are amenable to bending to fit different diameter tubes) the Sachs bosses are for 28.6mm downtubes only. A pity, as these are about the sexiest little pieces of metal I've ever laid eyes on.



So far I have all the tubes, the BB (Long Shen), and the miscellaneous bridges and bosses, from Ceeway. I expect the Lugs from Llewellyn any moment, and will start cutting once they arrive.

Silliness

I'm thinking of doing a bike with fancy lugs - not just the odd heart cutout, but material added to lugs and serious work. The Pacenti style just doesn't do it for me, but the original Malvern Star style most certainly does.

So I'm thinking of making a little fish five star. That resulted in spending the last few evenings slaving over inkscape, creating the perfect Little fish decal in the wonderful Malvern Star style.

Oh, for reference, this is what a real Malvern Star decal looks like. If you've ever seen one in the flesh, you'll appreciate what works of art they are: