A Completely New Frame

[Mike Mcdermid]

40th Anniversary Steel Allez « Singletrack Forum

I never knew what more to say

[Too Tall]

Go to heaven twice, both of you knucklheads. This great stuff.
Agreed on all counts, you've done the craft a tremendous turn by pulling this off and THAT is exactly why we are here...too support, collaborate, appreciate and defend the knowledge.
I feel a goose bump coming on.
Peace, Josh

I'll weigh in a bit here since I was the one that made this project happen for Mark, someone I count as one of my very closest friends...(in my spare time I am the janitor at DiNucci cycles). The tooling for this development is indeed owned by Mark and one of the things I wanted to try to accomplish is to protect him from the usual story that occurs in Asia where you suddenly find the product you sweated long and hard to design for sale by the very factory that did your development work. A big company can influence that and by funneling this work through Specialized we will have as good a shot at making that happen as is possible. There is a lot more going on here than just making 74 bikes. Mark & I were responsible for the bike line out of Specialized in the 80's up until I left the place in 90 and we had free creative rein to do what we wanted and had a pretty damn good time doing it. I always missed that collaboration and this was a chance to reassemble the band and to help underwrite Mark's work. We have always had a near perfect collaboration and someone is going to have to walk over my body to fuck this up for Mark. I would agree with everyone here that the 'S' has had it's share of colossal screw ups and has earned whatever reputation it has, so I get the hard bag here. But this collaboration runs way outside the usual program and is also fueled by my own passion for steel and my deep respect for Mark's skills and vision. Now all I need is to see some DiNucci crafted versions hit the road.

-BB

[devlin]

I think after all the dialogue I'd have to agree. There certainly are no negatives in all of this and I'm glad someone had the nous to actually pursue to the nth degree. As I said earlier I always believed that steel was capable of more but without the experience I wasn't sure I was actually right or where you'd even start.

One question, does the new tube set lend itself well to fillet brazing and TIG welding. ie. were the tubes 100% optimised for lugs or do the three methods benefit from the same development. I thinking grain, heat treatment, shape (flares, ovals, butts etc.)

[dinucci]

I think after all the dialogue I'd have to agree. There certainly are no negatives in all of this and I'm glad someone had the nous to actually pursue to the nth degree. As I said earlier I always believed that steel was capable of more but without the experience I wasn't sure I was actually right or where you'd even start.

One question, does the new tube set lend itself well to fillet brazing and TIG welding. ie. were the tubes 100% optimised for lugs or do the three methods benefit from the same development. I thinking grain, heat treatment, shape (flares, ovals, butts etc.)

That's kind of a hard question to answer. I did not consider tig or bronze welding when I designed the tubes wall thickness and butts. Hard to answer because when I walk the aisles at a NAHBS, for example, I see some bikes that should not be sold because of the way they are built. Some of those guys would use a tube that is too thin at the end and justify it by saying 'the bike won't be ridden long enough to break'. They may be correct in saying that, but I would not risk it. Some guys connect something to a thin part of the tube not knowing that in time the joint will fail by simply pulling a chunk out of the tube wall. That type of joint may work long enough to satisfy the customer but I wouldn't do it. These tubes may work for non lugged construction but I wouldn't until they had been tested. The other details in these tubes (butts) would benefit any type of construction. They are not that radical. Nothing on a design that is as old and well developed as steel frame tube is going to be radical. The seat tube has five different wall thickness, which may be a first, but I would not be at all surprised if it had been done before. These tubes were designed with these lugs to be used as a set.

It is just a matter of finding places to improve. The seat stays are allowed to be pretty thin because I added an internal re-enforcement as part of the seat stay cap, which adds strength to the joint. The brake bridge further strengthens to upper part of the seat stay assembly. I mount my stays to the side of the seat tube / top tube joint, as does Richard Sachs, J.P. Weigle and many others. It doesn't look "new" or different. I have made many types of joints in this area but I chose to use this method because the approximate neutral axis of the top tube and seat tube is there. The top tube has a nice big lap on the seat tube there which make that area nice and stable. The seat lug laps over that area to further improve it's stability. Then I, as does the above mentioned builders, make a cut in the lug to create a seat for the stay to rest in which makes for the thinnest braze joint. The more thin the braze the stronger it is. That strength made me think of making the brake bridge be designed the way it is in order to create a boxed upper part of the seat stay assembly to resist side loads. The seat stays have a long lever arm that makes it difficult to keep side to side stiffness. The stays get more thin below the brake bridge until they get near the dropout where they gain wall thickness for brazing. This is not rocket science, but I don't recall seeing a seat stay being butted in this way before.

Yesterday I met with a super nice old friend who turned me on to a really nice computer. It even has a refrigerator on the CPU. His company designs suspended and non-suspended bikes out of any material you would want. He also is responsible for these: Turn Cranks | Driven by Praxis Works
That is rocket science!

[devlin]

Thank you. I learned so much from that simple explanation. No, not rocket science but does need some understanding to put it all together. Lots of little nuances that make a difference to the finished product.

[shand]

Just thought I'd jump in here as I spent the afternoon with Tom and Keith from Reynolds today and it's pretty clear that an extraordinary amount of work went into this bike. I initially thought it was a very nice, well executed lugged bike but after chatting today I started to pick up on some of the many design features executed on this frame that I didn't pick up on when I first saw it. Top work Mark and all at Specialized and Reynolds who were involved.

[dinucci]

Just thought I'd jump in here as I spent the afternoon with Tom and Keith from Reynolds today and it's pretty clear that an extraordinary amount of work went into this bike. I initially thought it was a very nice, well executed lugged bike but after chatting today I started to pick up on some of the many design features executed on this frame that I didn't pick up on when I first saw it. Top work Mark and all at Specialized and Reynolds who were involved.

Thanks Steven
I clicked on your link and looked around. You are obviously nice people. I looked at the vimeo stuff. Really impressive! That made your frame geos make complete sense to me. Good work. Do you guys agree on a shoe that works best for those conditions? I wouldn't want to be on those open moors during a bad storm! Beautiful.

Looks like you are taking the front brake mount seriously. Good on ya. Do you get those chain stays from RTL made to your design?

Yup, Keith and Tom got a bit of a workout from me. They may have had a few 'nicknames' for me at times. It took longer than we initially thought but, I knew it could be done as I had made sure the models were correct, and the process was possible. I have made lots of tubes over the years.

Really, thanks for your kind words and keep up the good work.
Bicycle Manufacture - Scotland, (still part of the) UK!

[shand]

Thanks Mark,

Do you guys agree on a shoe that works best for those conditions? I wouldn't want to be on those open moors during a bad storm! Beautiful.

The trick there is to keep moving and keep moving fast!

Looks like you are taking the front brake mount seriously. Good on ya. Do you get those chain stays from RTL made to your design?

NO, we'd really like to get RTL to make something and we're working on it but for the moment our chainstays are made by Deda.

Yup, Keith and Tom got a bit of a workout from me. They may have had a few 'nicknames' for me at times. It took longer than we initially thought but, I knew it could be done as I had made sure the models were correct, and the process was possible. I have made lots of tubes over the years.

Yeah, when I brought that bike up in conversation, Tom went a weird shade of green and had to leave the room for a few minutes! But seriously, I think they love stuff like that, they're already talking putting some of what they learned in that project to work in other projects. I think we all need work to do that pushes the boundaries.

[dinucci]

Yeah, when I brought that bike up in conversation, Tom went a weird shade of green and had to leave the room for a few minutes! But seriously, I think they love stuff like that, they're already talking putting some of what they learned in that project to work in other projects. I think we all need work to do that pushes the boundaries.

Yeah, we need to push ourselves. The idea is to not get bummed by not being able to do something really huge. Just remember that there will be no 'revolution' with any of the materials we use, only evolution.

I went to the Oregon Bicycle Constructors Association show this last weekend. Bikes and beer and around 2,000 people in attendance. It has evolved quite nicely.

Check out this guy who is part Scott. He seems like a revolution but he got to where he is by evolving.

[Jake Rosenfeld]

Someone with better skills than myself should capture these photos and put them here on the VS just because; Mark DiNucci handbuilt classics

Everyone should read the ad, especially the part about the tires :-)