Wednesday, May 21st, 2008
Diverse projects have abounded the last couple weeks. I spent three days last week at Bikes Not Bombs in Boston, at a workshop sponsored by World Bike. We were experimenting with quick and dirty trailer designs, primarily for use in countries with few transportation resources. After a day of introductions and discussions of designs, I was privileged to team up with BNB founder Carl Kurz, and this is our creation:
The emphasis was on simplicity; no milling machines, no fancy tubing benders – we used a pulley off a car engine to bend the round stock to make the racks. Lots of folks took pictures during the workshop, which I’ll link to as soon as they’re up.
I also built a road bike for our friend John Sorensen; here are some pix of that:
And here it is with paint; it’s a crazy multi-layer custom action with a dark silver base and layers of translucent red over it. Hopefully today I can get some shots in the sun.
And yes, I said ice cream; Garrett and I worked on making his ice cream maker pedal-powered. We’ll debut it this weekend:
And somewhere in there I painted some more bikes for Bowen Cycle Works:
Saturday, April 26th, 2008
So I finished painting Steve’s single speed cross bike. Here are some pix. Also here’s a link to his blog which is quite excellent and hopefully will soon have tall tales about his hot new bike. Which looks like this:
Note the custom stop for the rear canti that lets you adjust the brake, & is slotted so you can pop the cables out for cleaning.
I also put a disc brake tab on an old Bridgestone MB-4. We made a brace to transfer the braking forces down into the chainstay; without that, I’ve seen many seat stays buckle:
And here it is primed and ready to rock:
Wednesday, April 16th, 2008
So Kipp came by yesterday and built up his S&S coupled road bike; check it out:
Above you can see the Ritchey quick cable disconnects. These allow you completely separate the two halves of the bike without getting all tangled or messing up your brake & derailleur adjustments.
The bike comes in at just under 19lbs complete; the couplers add about 10oz, which is handsomely offset by the superlight Ritchey WCS carbon fork. Kipp has promised a slideshow of breaking down the bike into a case, so watch this space!
My next bike is for Stevil Kinevil of Swobo. They make some of the hottest & coolest cycling clothing out there. For Steve I’m doing a single speed cross bike, matched to the nutty Hunter Supercrown fork he sent me.
This is going to be a very clean, fully welded bike. Steve’s focus was simplicity and durability; I’m using a mix of Deda Zero and Zerouno main tubes, with Columbus Zona S-bend chainstays and Spirit S-bend seatstays.
And here are some detail shots of the assembly:
Should be painting it by the end of the week!
Wednesday, April 9th, 2008
Circle A number 151, that is! Kipp’s demountable! Yes, that means it’s take-a-part-able. That doesn’t roll off the tongue quite as nicely, tho, does it now?
Let’s take a look:
I know what you’re thinking. Why the add-on seat color? Why not a fancy point like on Carrie’s? Well, I’ll tell you. This bike will often be demounted, and packed into a box with the seat post out of the frame. A fancy point would be very vulnerable without the post in place, and could cut its way out of the box to wreak havoc on the populace! IT’S EATING ITS WAY THROUGH THE HULL!
This week I also put together an adult trike for my friend Al. He’s having a hip replaced and isn’t doing so well on two wheels.
Here’s to a quick recovery! Coming up – Stevil Knievel‘s single speed cross bike!
Sunday, March 30th, 2008
Another first! We can’t stop! Local man-about-town Kipp wanted a bike he could take on planes and in trains, so for him we’re doing our first demountable. We’re using S&S Couplers, lovely stainless doohickies that allow you to break your full-size frame into two pieces! And then put it back together again! It’s true! Here they are:
So using these require that we take the top and down tubes, cut them in two, and braze the couplers in. I got True Temper tubes with extra-long butts (yes, we like big butts) so that I’d be brazing the couplers in the thick section; then I had to make a jig to hold the two sections of tube in line during the brazing. Kipp got this 80/20 which allowed us to jig it up nicely. Here are some shots of that, and yes those are lengths of old innertube holding the sections in place:
Then I mitered the tubes as usual. It’s a welded road bike with sloping top tube. Here are the joints before welding:
Here’s some shots of the frame in the jig, after welding & brazing, and out of the jig:
And here you can see how the entire frame & wheels will fit inside a wheel-size box about 12″ deep:
Room to spare, and that’s a bike with a 58cm top tube! Next up: Kipp’s complete bike, & Steve’s single speed cross bike!
Wednesday, March 26th, 2008
Liane picked up her mountain bike on friday. It’s totally green. I’m not even kidding.
Here’s some detail shots. She’s running Avid Juicy 7 brakes, Sram XO twist shifters, and a Sid Team fork. It has a cool lockout you can see inboard of the right brake lever.
Having painted the fork I wasn’t excited about putting zip ties all over it to direct the brake housing so I made a little aluminum holder that’s bolted in where the canti posts were:
And here’s Liane on her test ride. Look at that smile!
Saturday, March 15th, 2008
So I finished up Liane’s mountain bike this week. She wanted it this hi-visibility green so she doesn’t get shot at by any off-season hunters:
Here’s a closeup of the BB shell:
And here are those great Paragon disc dropouts:
Liane is going to be using mostly Sram XO components, with Avid brakes. The last hydraulic brakes I worked on were from Garrett’s 1972 VW bus so that’s going to be fun. She’s running a Sid fork which I took apart and painted the lowers to match:
I’ll post more pictures of the complete bike later this week. Also I painted two frames for other folks this week: first, this beautiful retro-style single speed made by Liane’s husband Mark:
And this road bike from Bowen Bicycle Works in Connecticut:
Keep them coming. Next week – Kipp’s s&s coupled road bike! stay tuned!
Sunday, February 24th, 2008
Yes, that’s right, a Circle A mountain bike. I know what you’re thinking. Do you people even make mountain bikes? Do you even know how?
Well yes. Yes we do. We just don’t do it all that often.
There are some different challenges and design considerations, but if it’s a bike we like it. Especially a light hardtail like this one, for our great friend Liane.
Among the reasons I’m excited about this bike is that it’s going to be all welded, which doesn’t happen that often. As you may have seen with Carrie’s, often when we do welded road bikes we still use a lugged BB shell for a little fanciness and also for super fast jig setup. There are lugs and lugged BB shells available for mountain-style geometry, but for Liane we’re making a pretty small bike with some serious angles – the top tube is sloping at 16 degrees – so I like the flexibility that welding gives. Also it lets me size the tubing more precisely for her size & weight – in this case I’m using a 35mm Deda Zero down tube, 28.6 Zero top tube, and Zerouno externally butted seat tube:
The chain stays are Columbus Zona, and the seat stays are Zona Road S-bend. I was able to use these and get enough tire clearance thanks to the Paragon disc brake dropouts:
They’re very pretty and svelte and transfer the considerable forces from the disc brake down into the chainstay, and are helpful for tire clearance (clarence) because they’re long and allow the seat stays to start relatively high up.
So doing a fully welded frame (or for that matter a fillet brazed one) means no downtube, seattube, or chainstays extending into the BB shell, so all the miters have to be super tight:
Here’s the frame fully jigged up before tacking:
So first I just tack the front triangle in the jig, and pull it out & put it on the alignment table:
As you can see each joint is just tacked in a couple of spots. The tubes will pull a bit toward wherever you weld first, so I look at it on the table to come up with a welding pattern that will set things straight and true. In this case, the seat tube and top tube were spot on, but the down tube was pulling a little left (go figure). To correct this, on the welding table I finished the beads on the right side of the bb shell/dt joint first. Then I put it back on the table to make sure everything is still jake, and so on. If things go my way, I won’t have to do any cold setting at all.
Then it’s back into the jig to tack on the rear triangle. Here’s a look at those sexy stays:
And here’s the full frame, coming in at 3.5 lbs. Now it’s time for bridges, braze-ons, and paint!
Next bike? A Circle A first – an S&S coupled bike for Kipp! Stay tuned!
Friday, January 25th, 2008
I just finished a bike for Providence luminary Carrie Cannon. It’s a commuter single speed, and in addition to being lovely in general, it’s a good example of a melange (if you will) of construction techniques.
So what we have here is a frame with a welded front triangle, lugged fork and BB shell, and capped seat stays. There’s a lot going on at the top of the seat tube so let’s take a closer look, shall we?
OK, so as you can see the top tube is TIG welded to the seat tube. To make this super strong, we use an externally butted Dedacciai seat tube – it takes a standard 27.2mm seat post, but the wall thickness increases to 1.1mm at the top of the tube for a stronger weld. Also this makes it strong enough that we can sculpt a nice point into it. That point along with the old-school capped seat stays give it a very classic look, especially when combined with the lugged BB shell:
Also there you can see the mount for a rear fender.
Carrie’s deciding on parts, I’ll post some more pictures of the complete bike hopefully next week.
Also I promised to write about stripping paint with invisible rays! and I didn’t lie! check this out:
Garrett, our erstwhile partner and espresso machine tech, made this for stripping paint. It’s an infrared heating element with a handle; for home use the idea is that it doesn’t get so hot as to vaporize the lead in old house paint. But it works great on bikes too. It gets the top coats soft enough to easily scrape, and from there we can abrasive-blast down to bare metal. It’s much nicer than nasty chemical strippers and you don’t have to worry about any of the stripper lingering on the frame. So if you send in your bike for a repaint this is the sort of high tech, kid glove treatment it’s in for.
Saturday, January 5th, 2008
Before the holiday madness descended I did a repaint for our friend Patrick of Java Speed Scooters.
It’s an old Tommaso that we did a crazy yellow pearl paint job on. This is one of the better made frames that’s come thru here (the work of our own hands excepted, of course) – great detail work and tons of neat cutouts and embossings.
You’d be shocked, shocked how nasty some of the vaunted classics of olde look when you get under the paint, but this is really a work of art. You can see more pictures here.
Coming up: lisa rides, a new frame for hometown hero Carrie Cannon, stripping paint with invisible rays, and more!