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Archive for April, 2010

Classic Gothic.

Wednesday, April 28th, 2010

Long before young people stood outside book stores wearing black lipstick and eyeliner there was Gothic design and you can count me as a fan. I’m not so much a fan of detailed Gothic stuff but I love the simple long lines found in simple gothic design – think less gargoyle and more flying buttress.

Anyway, I’m doing prep work for a Rando style bike that will use a classic 1″ top tube and Gothic 3 point lugs. The lugs are unique with their 3 points on each tube (as opposed to two) and their flying buttress reinforcements. They are very tricky to work with and take way too much time but I enjoy working with them and glad to do so. It takes a solid 1/2 day to cut and shape them into the pictured form and it’s worth every minute. The buttresses do not really perform much of a function really (unless looking cool is a function) and as much as I like every little thing to have a purpose and earn it’s keep I do these just for the look.

I’ll get some photos posted sometime late next week when these lugs find their way off the scrap tubes in the photos and onto and into the real frame.

Dave

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Purple, white, pink and Sram Red.

Friday, April 23rd, 2010

This JK Special just went out the door to it’s new home in Ohio. I hope it gives it’s owner many years of hard miles and long rides.

Have a great weekend.

Dave

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Spring Colors.

Tuesday, April 20th, 2010

I just got this JK Special Terraplane frameset back from Joe Bell and I must say it’s pretty damn cool. JB used it in his booth at the San Diego Bike show so I’d seen a few photos of it online before it got back to me but they didn’t do it justice – just as these photos don’t, now that I think of it. In the sun the paint looks wet and a foot deep.

The frameset will get built up with a Sram Red kit in a few days and I’ll have more photos of it then. I look forward to getting this under its owner soon. That’s the best part.

Dave

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How do you do that part II.

Thursday, April 15th, 2010

There are certain things that I do on my bikes that aren’t obvious once the bike is built and painted and are for the most part my little secret but I’m proud of them nonetheless. One of these things is my side tack seat stays.

Here’s a short lowdown on how I do my side tack stays. It can be a bit hard to picture what is going on and I’m hoping that the photos will help fill in the blanks.

The first two photos give the basic idea. The upper end of the stay is cut off at an angle and then that newly exposed end is filed to leave a curve so that a piece of tubing can be brazed in. You can see the one stay is prepped to have it’s cap brazed (cap tube set to the side) on and the other stay cap has already been brazed on. In the end the concave surface of the cap will be the inside of the tube I’m brazing on.

The 3rd photo shows the two stays with their caps brazed in place. One of them has had a rough trim using tin snips.

Photo 4 shows a finished stay cap. The finish and shaping work is roughed in with a dynafile and then the detail work is done by hand. The shape is done by eye and the hard part is getting the two stays to look exactly the same.

The 5th photo shows the pair of stays all prepped and read to be brazed to the seat lug. I make the caps long and then curve them so they wrap around to the top side of the seat lug. I do this for two reasons – the first being that it gives a very large area of contact between the stays and the the lug and that makes it a very strong joint. The second reason is that I think it looks really cool and is a way for me to show off a bit. It’s not easy to get it all to be symmetrical and balanced and I love the resulting look.

Photos 6 & 7 show what the joints look like after brazing but before any finish work has been done. It’s very important for me to get the brazing very clean or the finish work will take a lifetime. The pictured joints came out very clean and will make for quick and easy finish work.

The final two photos so the seat cluster all finished and ready for Joe Bell to work his magic. The finish work is done with emery cloth that has been ripped into narrow strips so I can get into the nooks and crannies. You can also now see the top of the seat lug has been cut off and shaped and the clamping slot has been cut.

I use this traditional method of fabricating stays caps because it allows me a good bit of latitude in shaping them for my own personal look and because they end up being hollow right to the top. Many builders use seat stay plugs which in the end look much like this once they are covered in paint but what they really are is solid cast plugs that are just brazed into the square cut ends of the stays. While they work just fine I don’t like adding the extra weight and I certainly don’t like having to settle for the look that they give. Is there a functional difference on the road? Will you be faster with traditional stay caps like I prefer? No. But I like them anyway.

That’s it for today. Enjoy spring.

Dave

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How do you do that?

Tuesday, April 13th, 2010

One of the options I offer on my bikes is internal brake cable routing and for many the way this is done is hard to picture so I figured I’d do a bit of show and tell. There is no performance advantage to internal braking and it’s done just for the clean look.

This series of photos will give a rough idea of how this works. Most of the photos were taken with the frame upside down in the vice because I place the internals on the bottom side and it’s easiest to work with the bike upside down – either that or I get down on the floor on my back and I’m not a huge fan of that.

The first photo shows the brass tube and the stainless end barrel it is about to be brazed to. I use a 3 piece system that allows for just the cable to pass through the small brass tube. The brass tube is very low friction making the braking feel and modulation very good and solid. I do not like the internal systems that are larger and use brake cable housing through the entire length. These can make the braking pretty mushy with that much cable housing to compress every time you squeeze the lever. I also like that the 3 piece system is a good bit lighter overall.

Next you’ll see 3 holes have been drilled into the top tube. These holes will be merged into one long oval hole to accept the internal barrel with a hand file. You can then see the barrel being test fit into the hole. There is an identical hole being made at the rear end of the top tube also for the internal to exit.

With one barrel brazed to the small brass tube I then test fit the system into the top tube and I just slide the rear barrel into place to be sure all is right. I then mark and cut the brass tube to the proper finished length and end up with a brass tube with a barrel brazed to each end.

Now it’s a matter of feeding the assembly into the top tube for a final test fit before brazing it in place. You can then see the white sticky flux lathered all over the part making it ready to silver braze.

Once brazed it is allowed to cool naturally to room temperature and then it is soaked in very hot water to remove the flux. With the flux removed you can now see the silver brazing work. Next I go into the finishing aspect of the process and it involves mostly emery cloth. I use a Dynafile (hand held belt sander) to put the small scallop in the end to give it a tapered and finished appearance.

The final photos show the bike in it’s natural orientation with the internals pointing down slightly. This helps keep moisture from entering the internal tube and gives a nice natural curve to the brake cable housing as it enters and exits the internal. One very nice thing about this system is that with the stainless barrels and brass tube there is no risk of corrosion and they seal the tube so nothing can enter. It’s a fully sealed system.

One of the fun things about this process is that it can all be done by hand very quickly and efficiently. It takes me about 25 minutes of hands-on work to do the whole thing and much to many people’s surprise there is no measuring done at all. It’s all done by hand and by eye and without using digital equipment or lasers. I have nothing against that stuff but if you don’t need to use it it’s best to leave them idle.

That’s it for now. Happy braking.

Dave

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JKS for North Carolina.

Thursday, April 8th, 2010

Here are a few shop photos of the latest JKS to come out of my shop. It’s headed to JB’s for paint at the moment but will ultimately end up in North Carolina. I’ve only driven through N.C. but hear the riding there is world class. Maybe I should deliver this one myself!?

Today I start on a classic lugged all-rounder with a threaded fork destined for the Bay Area of California.

Stay well,

Dave

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Metallic Brown II.

Friday, April 2nd, 2010

It may not be Bamboominum but it’s still pretty slick I think. A full race JKS with Ultegra and Fulcrums. With any luck he’ll have it for the weekend.

Dave

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I’ve seen the future and the future is now.

Thursday, April 1st, 2010

Over the years I’m been very lucky to have been able to have work with most every frame material out there and when I started my business I decided that for me steel was the best material to use. I love the way it rides and that it has such wonderful fatigue properties so it will give a lifetime of service. The one thing I don’t like about steel is that it’s not renewable and to make more of it requires digging a big hole in the ground and then lots of energy to turn that ore extracted from that big hole into the material that the tubes are made from. And while it’s true that steel is recyclable one can not make high strength steel from recycled swingsets – high strength material needs to be made that way from the get go which brings us back to that big hole in the ground.

With the help of my wife Karin I started working on the renewable issue a number of years ago. We looked at materials like carbon which is pretty cheap and easy to work with but hardly a low energy, low impact material and it certainly can’t be recycled or renewed. We briefly considered magnesium but the energy needed to refine this abundant material was too high and most people would have no idea where to take their magnesium bike to recycle it. And then we considered bamboo.

Many people are now building with bamboo and it’s a wonderful material. It’s a perennial evergreen that is one of the fastest growing plants in the world with the added benefit that it’s best grown in South East Asia where they cold certainly use the money and the work. But using traditional bamboo construction techniques is hardly a low impact or renewable way to go. It requires the use a lots of epoxy that, while stable and non-toxic once cured, renders the bamboo un-recyclable. In working with local farmers in S.E. Asia through international aide agencies I’m proud to say we have had a material breakthrough in bike building materials that at once make the entire frame renewable, recyclable, low impact and extremely light and stiff. I’m pleased to introduce to you now – Bamboominum.

In working with local fair trade farmers we realized that we could improve on nature and bamboo during its growth so that it would not require the use of epoxy to construct a frame with the side benefits of it being water and rot resistant and much stiffer in both bending and torsion than traditional bamboo. We discovered that if one fertilizes the bamboo with aluminum powder starting at its gestation period and through full growth that one can in effect blend the material properties of bamboo and aluminum into one fabulous new material – Bamboominum. The bamboo plants grow so quickly they will suck up most any material presented at their roots and if one gives a constant diet of aluminum powder to a plant it will take it up into it’s cellular structure much the same way that celery did with ink in those school science experiments you did when you were a kid. The bamboo itself grows almost as quickly as old school bamboo so a farmer can grown many frames worth of material in one day on a small plot of land and this gives them an alternative to growing poppies or marijuana.

Bamboominum looks like old school bamboo except it’s got a grayish color instead of the normal tan color. This was at first an issue with the locals as they thought this was mocking the Gods and that they would suffer the wrath of a vengeful God once he saw what they had done. This almost ended the project at its inception. But we were able to convince the farmers that God was busy doing other stuff and wouldn’t see what they were up to and then we were able to move ahead.

Bamboominum is of course renewable and it’s also fully recyclable. We are currently in negotiations with specialty firms here in the USA to turn used Bamboominum frames into tiki torches for lawn and patio use. Remember – reuse, renew, recycle!

There are a few things about Bamboominum that make it very unique. First is that due to its extremely high aluminum content it can be welded using traditional methods. Welding is of course the easiest and cleanest way to join aluminum tubes and can be done by most any hack welder out there. The second extremely unique thing about Bamboominum is that it can be grown in such a way that the frame built from it can be at once laterally stiff and vertically compliant. Fertilizing the plant on two sides more than the other sides so it in effect makes the Bamboominum stalk asymmetrically stiff. This has been the holey grail for most framebuilders and I’m pleased to announce that the goal has at long last been achieved.

We expect to be building with Bamboominum very soon but frames will be limited to belt drive fixies at first to satisfy pent up demand for them. All Bamboominum frames will be build around the new bottom bracket and headset standards of BB90 (a flex free 90 mm BB spindle) and HS90 (a flex free 90 mm fork steerer diameter – because this stuff can never be stiff enough). The third photo below shows a worker harvesting Bamboominum to be used for fork steerers.

Bamboominum will not be cheap starting at $23,500 for a frame and fork set but the few select owners can sleep easy and have just grounds to brag to their coffee shop buddies that they are cooler because their bikes are like their coffee – fair trade.

Please keep an eye on this space for further announcements about the breakthrough that is Bamboominum. We will be announcing delivery schedules and options soon.

The future belongs to Bamboominum!

Dave

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