I too would love to know more of the technical side. Where shape was the driver and where material was the driver and what you had to change to make it work. I imagine some of the info you'd like to keep quiet at this time but anything else I'll soak up like a sponge.
I'll go out on a limb though and say I'm not a huge fan of the CS bridge. Personally I like clean, simple minimilist design. The least amount of material req'd to do the job properley. Even the shape of the SS bridge is not quite right for me. I remember reading a test somewhere that concluded the CS bridge does not contribute to the stiffeness of the frame.
Mr DiNucci, What are your thoughts on this and is the CS bridge purely for mud guard mounting or did you find something in your research?
__________________________________________
"Even my farts smell like steel!" - Diel
"Make something with your hands. Not with your money." - Dario
Sean Doyle
www.devlincc.com
https://www.instagram.com/devlincustomcycles/
https://www.flickr.com/photos/139142779@N05/
Hey Jonathan,
I just got off the phone with Mark and I think he is offline for the evening. I'll let him pick this up in the AM, but I wanted to clarify my comments re Reynolds. It was not a bag on Reynolds whom I respect, it had more to do with how we could achieve some of the more extreme tube manipulation we were after in the chainstays and the blades. The chainstay shape at the dropout socket is pretty challenging and took a fair bit of experimentation to sort out. The blades had to be pre-bent for production (something nobody here would have to bother with) and because of the OD's, tapers and wall thickness it was easy enough to get wrinkles. Fixing this one resulted in changing heat treatment and slowing other processes to essentially double normal production time. Reynolds was entirely accommodating and perhaps bent over too far to get this right. Great bunch of guys.
BB Bainbridge
I just (finally) looked at the links and eBay listing and was mildly surprised to see the 1 1/8" spec on the fork atmo.
Hey Asshole!!
A blank check? Bought and paid for by Specialized?
If I use the amount of money it takes me to live my rudimentary lifestyle, multiplied by the number of months that I have spent solely on this project, I find that I have used over one hundred thousand dollars of my own money to bring this project to where it is today. My credit card is maxxed-out at 30K with me seeing no way to pay it off in the foreseeable future. Can you see how deeply I believe in this bike?
This project would not have been nearly as successful, or maybe not have happened at all if it were not for the help of Specialized. They have staff who have worked in the bicycle manufacturing sector since the 1980's who speak the native language of the counties where the parts are produced. They are familiar with the process's that were used in this design. They have been paid to work through the problems that were created by the vendors. I didn't get all of the details that I had wanted, that I had designed into the CAD models that I supplied, but the design intent has come through in spite of the myriad of problems that arose during the development phase of this project. This project would have faltered if I didn't have the 'pull' that one of the largest bike companies in the world can offer. This is a miniscule undertaking for the bike industry, where no one involved will make any money because of it's extremely small scale. This could have only happened because of the influence that Specialized has. They will not make any money on this project. I doubt that I will ever recoup my money from this as well.
I will try to address "outlandish claims" through my explanation of the the other frame details elsewhere.
Mark Dinucci
I'm still none the wiser after 3 pages what's on sale?
If I'm doing it right, my analysis is that Mark DiNucci is officially a victim of Specialized's own blowback--perhaps unbeknownst to him.
No value judgement made on him by me, however.
I would, however, expect anyone associated with the company to be assailed by some members of the industry from time to time for reasons widely known.
Would be cool to have his input, aside from said association, and reckon that none of this would have occurred if it weren't for the mention of the the Company.
Mike Anderson
Wellytown
Nooooo Zeeeland
My apologies on perhaps a misinterpretation on my part from this quote from here The Specialized Allez, Reborn | RKP
"This limited-production Allez—they will only produce 74 of these—features a new tube set and a special lug set to accommodate the tubes. To put this in perspective, Specialized allowed DiNucci to chase his muse, or as Bainbridge put it, they “wrote him a blank check.”
I took it literally, but maybe it's figuratively.
Regardless of the investment costs, I think others here have some curious questions about your product that they would like some answers too, including my original question on the first page.
I keep getting spit out/ logged off. I have commented on this bridge here:
https://groups.google.com/forum/#!se...E/k5PVw66bnFkJ
I hope this link comes through.
Sorry you don't like the bridge. As usual when something new comes along it will inevitably come under scrutiny / suspicion as well it should. At least I am always from the "let's look at this thing long and hard before accepting it" camp.
The cs bridge definitely does contribute to the frame stiffness. At least the way I usually make them. This new bridge does not add as much stiffness as another way I make them but it will not negatively effect the fatigue life of the stay. If someone wants to buy a frame from me I am sure that I could find another way to make a bridge.
If you look at the photos of the pre-production parts you may be able to see how deep the cs sockets are. There is the most amount of 'interface' between the BB shell and cs that I have seen. This is not a production friendly approach to this area but it sure creates a nice connection between the two parts. A bridge may not be necessary with this design but I would not want to build without one.
As far as your question regarding shape vs material goes I'll give that a shot. I should answer this in the question from Mark Kelly but I'll put something here. The materials we have to use these days are pretty darn good. For example the BB as a unit is a bit of a mess because there is no clear path for the loads from the front of the frame to go through the BB shell to the rear wheel. I tried to make this BB stronger than previous shells by adding material where it would be beneficial. The size of the tubes made for an opportunity to stiffen up some of the traditionally problematic areas. The chainstays are about as big as I could cram in there which allowed for the 'connection' between the cs and the seat tube to be beefed up relative to most existing designs. The xsec of the chainstay at the BB end is based on a shape that I have had good luck with in the past. It is basically an oval with the major axis ends being 'flattened' which helps to stiffen the stay to side loads. This was not an easy shape to produce because the tube gets allot of it's strength from cold working. The cold worked (hard) steel needs to be shaped into the design shape while in it's hard condition. The chainstay is butted on each end (hard steel), then tapered (harder steel), then has the 'oval formed (harder again), then has the drive side end shaped (harder yet), then is heat treated (final condition). The material used in the BB is an alloy steel which is heat treated after casting to refine the grain structure and increase strength / toughness. The design of the BB also uses full radius fillets to help spread the loads. You can see other BB shells that have almost no fillets at the joint intersections. The final edges of the sockets have about as thin a wall as I wanted which then transition to a wall thickness that is appropriate for the loads / stiffness that I wanted. These cast parts are modeled with each socket being designed for each location. That is, the design is not simply a cylinder or a cone intersecting each other but a fully swept design that meets the design intent as well as I could conceive it. This adds allot of time to the modeling but allows for the best solution to the problems identified. If I hold the parts in my hands and rotate the parts I still can't easily see allot of the details, not to mention someone seeing a mere picture on the internet. The only way to get this level of detail is to model the part, use cross sectional / mass property analysis and keep tweaking it until you are satisfied. Knowing the strength of the BB shell material at it's different locations and the strength of the tubing allows me to design the butts (thickness, location, length, etc.) to best suit the joint (to the best of my ability anyway, I am only human). The testing has shown really good results. I have seen BB shells break in just about every way they can and have used this info to help design this new BB shell and tube joints.
Boy, if this isn't a confusing, messed up explanation. Something to chew on for a while though.
Mark Dinucci
Mark, thanks for hanging in there and supplying us with your knowledge. It's the reason I read this stuff and I enjoy hearing about the process and the means to the end.
Bryan Davis
Hey!
Mildly surprised!
You should have heard, felt, experienced what I did when I showed these new dropouts to one of our favorite frame builders. He is a guy who lives sorta near you and is known for making the best rando bikes the planet has ever seen. He was disappointed to see the sockets. He was more than mildly surprised. I felt as though I had 'sold out' when I experienced his reaction. I had to think long and hard about using sockets because I don't really care for the aesthetic but my final analysis resulted in the sockets. It was a pragmatic decision. The drive side chainstay needs to have three fairly precise cuts made in it to fit the dropout so it's not really very production friendly. Strong though. For the most part I like the way my bikes look but I try to design around what will be best for fatigue life and weight and leave the aesthetic to work it's ownself out.
The steerer is indeed 1 1/8 diameter. I designed a more lightweight than usual steerer tube but not the lightest. I can buy the lightest from the big names. I used a similar approach to the butt length, taper length ratio as I used on the other tubes. The forks went through the most stringent testing I am aware of existing. After the test results came in I felt that wonderful feeling that only us who have been doing this for a long time can feel. The feeling of confidence that we feel when we know that the product won't fail. I am now confident that if I put a 250 pound muscly meatball with 60 pounds of loaded touring bags on it, it will not fail. So NICE of a feeling! The blades are one size up from the normal Columbus size and are shaped more on the round side of oval. They came in lighter weight than our regular Columbus SL blades as well.
The crown and fork tips are heat treated alloy steel. All of the tubes in the bikes Specialized are making are 853 air hardening steel.
Mark Dinucci
i keep getting spit out, must be my old software?
i keep getting spit out, must be my old software?
I think there has been some misunderstanding here. Sure we have Air Hardening steels, Stainless steels (one from 'lumbo and three? from RTL) but we would have more choices in thickness, diameters, butts, etc. if the big makers were pursuing the use of steel. When BB said it was hard to find the skills to pull off the development of this project he meant that we were not-pleasantly surprised to find a lack of understanding from the vendors. An understanding that was inherent when working with the japanese in the 80's/90's.
Let me post some pics and give one example.
I had to send these pics to the casting house because they said they couldn't make some of the details I
Sure we now have the best steels we have ever had and we have CAD/CAM but you can't get the quality of the parts shown in the pics. My models are very well done. I understand the casting process. I designed and modeled the parts knowing how the model to part process is developed. Having a good model allows me to stand in line at the factory waiting for the process to begin. The model gets "expanded" by some factor to account for the wax, and to a smaller extent the steel, shrinking through the different stages of the process. This is the first place that the model is manipulated and is therefore not my model any longer. You would think that if I send a model, the model has it's size changed, and then it gets a tool path run on it that there would be no room for human error because it's all software doing the work. Not so. I had details dropped that I had to work hard to get replaced. I had to make design changes to accommodate the abilities of the factory such as, increasing the thickness of some of the smaller details. Details which were more easy to produce than the Nagasawa dropouts have. In other words, the craftsmanship in the factories is not what it once was.
i am taking too long, keep getting spit out. i will add to this in a bit.
Mark Dinucci
Here in another example. If you check most of the new crowns you will find that something as obvious as getting the steerer bore perpendicular to the "plane" that is described by the fork blade pockets is not available. It really pisses me off because I have a fixture that allows me to get the brazed tip / bent blades cut to within around 0.1mm (four thou) of what the computer tells me is correct. This allows me to build a straight fork right out of the jig. Even after I had supplied the factory with a drawing indicating how to machine the bore I got something else. I don't know at this time if I will receive crowns with the correct bore placement. REALLY?
Mark Dinucci
Is that a blatant plug?
I don't know if I ripped you off. Isn't the regular SL blade based on 24mm diameter? What ever, mine is only one size up. I don't remember but I think it is based on one inch dia.
And the tubes are all sourced from RTL. mama mia!
besides, i wouldn't tell the world if i ripped you off, would i? pia madona!
Mark Dinucci
Hi Mark-
Did you ask them to mill out the fork blade flats referencing perpendicularity to the bore or vice versa? Your drawing/instruction seems to indicate that the part must be fixtured referencing the fork blade recesses, then machine the steerer bore based on that datum. Is that correct?
Great thread and thanks for posting, BTW.
Tom
T.o.m. K.o.h.l.
Oh, I know it!!
T.o.m. K.o.h.l.
You know, since you're using curved blades on the fork, all three surfaces referenced are parallel to the Z-axis on a milling setup. Should be fairly straightforward to set up with proper fixturing.
Are you having trouble due to the newness of the product to a specific vendor or is "the industry" unable to handle this issue? Can you outsource the machining to a qualified vendor?
Tom
T.o.m. K.o.h.l.
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