LeicaLad 

I'm afraid to ask . . .

. . . ball park cost?

clasher

I am interested in one, perhaps two depending on price.

JohnDThompson 

Ofmega also used 118mm BCD on some models. Zeus was 120mm BCD, at least the six cranks and 2 dozen+ Zeus chainrings I have here are 120mm BCD.

Sutherlands 3rd/4th edition has a fairly comprehensive BCD chart for vintage cranks.

John E

One can do my 130-to-128 mod -- which lets me hang any standard road double ring on a proprietary Nervar Star spider and essentially entails stretching each mounting hole inward by 1mm -- to fit a 120mm ring to a 118 spider.

Andycapp

I'll also be working up a few more designs for you guys to look at. Once the machine is set up, it's just a matter of running different programs to get different parts so we don't have to settle on just one! I'll out of town for a speed-skating meet next weekend, but I should have no problem getting a few of these done by the end of the month (fingers crossed).
-Andy

cyqlist

Thanks, I knew there was another one besides SR but had forgotten it. Incidentally there was another model of SR Apex with 86mm BCD which was interchangeable with Stronglight 99.

I have to admit I don't have as many Zeus cranks and chainrings as you, but the ones I do have are 119mm BCD, not 120. It's funny, but I can google "zeus chainring bcd" right now and find them listed or described as 116, 118, 119, 120, 121 and 122. As close as I can tell they are exactly 119, not just closer to 119 than 120.

My old 1974 (1st edition?) Sutherlands does not list BCD dimensions, apparently it was not common to describe chainrings by that dimension until later. Back then you would just say that Zeus did not interchange with any other brand. I never bought a newer Sutherlands - they always seemed too expensive.

Incidentally relatively recently (3 years ago) I came across this picture of what appears to be a 144mm BCD Zeus crankset (note Campagnolo chainring mounted), I never knew that existed until then, and have never seen or heard of it anywhere else.

LeicaLad 

Andy,

I think this is all very generous of you, but why not take a deep breath and put the pieces together and give eye to how it best looks? Your initial thought about added cut-outs or sculpting was correct. Not so much radical as in harmony that best takes advantage of the Stronglight – especially model 93 – arm design. Both artistically and structurally. As it’s bloody strong by materials, I’d lean to some play with the art.

Eh?

Of course, it’s easy for me to say, as it’s not my skill set to do this design, let alone CAM, work.

Measure twice, cut once. All that sort of stuff.
*

As for Zeus. Sutherlands 6th says 120, but I’d almost come to believe 119. I’d offer to measure the one NOS Zeus ring I have, but you’ve seen my advanced talents in this regard above. (!)

Zeus also did have, 100% certain as I've seen several, a model with 144bcd. Their true Campy clone.

Finally, I offer an image of the minimalist triplized crank – actually the only triplized crank I have.

I have been waiting, for many (8) months now, for a frame that is still with the refinisher in Yorkshire, England. I have the entire build, with lots of redundancy options, in hand – minus only the brake levers. I hope this frame comes . . some day.

I bought the arms cheap. Sent to Bob Freeman at Elliot Bay Cycles in Seattle for drilling.



This image is more for contrast. The idea that a C&V triple can be elegant. The Stronglight star pattern suggests much more intricate possibilities.

I mean, this one is pretty cool, and that's only the first we've actually known.



Model 93 outer rings will look quite different, but so do other 122bcd rings.

Andy, I hope this is useful. As for Sales rules, I’d call this “a group project” that looks like a few prototype costs will be shared. Eh? If a sudden crush of demand looks to launch a new career track for you, we might revisit that. IMHO, obviously.

Owen
LL

unterhausen

It's best if discussions of money are handled off-line via PM, thanks. Rules are here

Andycapp

Agreed. Let's keep this to development and ideas here. PM me if you'd like to go to "the next level".

So, we've got one design. I'm going to build on that a little by removing a little more material and adjusting the existing cut outs to match. I'd also like to draw up a set based on the 104 "drillium" look with the triplizer and granny drilled to match. I could also use some advice when it comes to the actual tooth profile. What I have drawn is a standard sprocket profile with the teeth slightly truncated (not pointy). Should work fine but I feel there might be something lacking other than pins and ramps when it comes to shifting smoothly. Might have to wait till I can put it on a crank and try it out...
-Andy

cyqlist

Sorry to belabor the Zeus issue in this thread, but it's been a sore point with me for years. I'm surprised that Sutherlands would get it wrong, but would be more surprised if they made them in both 120 and 119 bcd.

Here is my photographic evidence, taken on a flatbed scanner.




The trig constant to convert distance between adjacent bolts to bcd for a 5 arm crank is 1/sin(36º) = 1.7013. Or for a given bcd divide by 1.7013 to get the expected bolt to bolt measurement. Thus:

120mm bcd = 70.53mm bolt to bolt
119mm bcd = 69.95
118mm bcd = 69.36

You can look at the above and see for yourself which it is.


Slightly more on topic, here is my triplized Zeus crank which I drilled for a 58mm bcd granny ring:



I later regretted that I didn't at least attempt to drill and thread the holes blind so they wouldn't show from the outside.

jonwvara 

Okay, I'm convinced. Andy made the same point to me--the material is strong, so why not make it lighter/classier looking? I admit that if I were an architect, every building I designed would probably look like a cement-block gas station.
So okay, let's go light and elegant, although pure brute function is still the thing that concerns me most.
JV

LeicaLad 

Ooooh! One of the exotic and uber-rare 36t Zeus rings. I've let so many chances pass at buying a nice Zeus crankset, simply because I'd only want one if I could score a 36t ring. Otherwise, why leave a Stronglight 93 behind. As for the drilling, notice that even the Campy factory drilling goes thru the arms. When there's bolt there, it looks okay.

Thanks for the measurements, too. I've long been a fan of Zeus parts, but have yet to own a crankset. (But I have a NOS 50t waiting for the day a 36t ring appears!)


As for costs, et. al. Several of the forums have arranged group buys, etc. etc. I'll not push the subject, and happy to deal thru PMs, too, BUT this ain't commerce and is within forum rules. This is creative research and prototype development. Defensible, FWIW.

jonwvara 

Looking at my 93 crankset, it looks like one obvious approach would be to "skeletize" the triangular tabs of the triplizer to approximately match the cutouts in the crank spider. It would be necessary to go a little wide around the bolt holes, obviously. That would look fine on it's own, I think, though I'm not sure how it would look when everything was bolted together--might look kind of visually confusing/busy. But that would seem to make more sense to me than round holes or something like that.

753proguy

Has anyone checked with fyxomatosis in Australia? I had him make some 151 rings for me about a year ago. Nice work, fair pricing.

Highpath has stopped making custom rings, and CT in Japan retired with no replacement. Who can we get to make a bunch of chainrings? I have a wishlist of maybe a dozen ones of various patterns, and I'd be willing to buy quantities of each one. There is a US source (that makes the Origin-8 and similar stuff), but their minimum run is 100 pieces per ring, and they use a pretty low-grade alloy, I think. But they are very inexpensive....

753proguy

No, Zeus is 119. Isn't it? I'll go measure one, I guess....

753proguy

Zeus was great at copying Campagnolo. Spain ignored international patents for decades. They made a 151 double at one point! Had the raised pedal area, just like a 1958-1960 Campagnolo Record arm.

Andycapp

So here's a "104" version of a triplizer. I started with this one because I've got the crank and rings in hand, so that helped to visualize it and being a machinist I'm drawn to the idea of putting holes in stuff! The good news is I've learned some techniques and should be able to come up with a "93" version fairly easily now. What do you guys think? Stay tuned...

-Andy

PS I've also drawn the crank arm and the 52t and 24t rings. It's quite the mess shown all together. I can gin up a solid model if you want(need). But it's not needed for programming G-Code so I'd rather keep moving forward.

More good news - I've discovered that a 24t will barley fit inside the 107mm ID allowing me to make both rings out of the same piece of material!

jonwvara 

As far as I know,fyxomatosis just bought their chainrings from Cycle Underground, which seems to be out of business, along with Highpath.

jonwvara 

Very nice! I think it looks good. As I said before, I think it's easy to go overboard worrying about appearance. The fact is that even if a ring is a work of art on its own, it's going to look different--and largely be hidden--once it's mounted behind the outer chainring and the crank spider. As long as it works, it doesn't matter all that much to me what the ring looks like.
That said, I think that something a more angular, rather than "swoopy" might be appropriate for the model 93. Something like the triangular tabs of my brutalist design but with cutouts in them, along the lines of the coutouts in the 93 spider?
By the way, do you need a 93 crank to use as a model/pattern? You can borrow mine if that would be helpful.
JV

pastorbobnlnh 

Jon,

Let me offer two pictures of my two 144BCD triplizers. The first is made by Williams and it came with its granny ring, which is 31 teeth. I have never checked the BCD on this granny ring. I'm not certain when Williams stopped manufacturing this triplizer.



Not very elegant with it's triangular tabs blocking the area between the spider arms. But it gets the job done mounted to the traditional Campy crank.

The second one is the modern (still being manufactured?) tripilizer made by TA and did not come with a granny (74BCD). Because of this I ended up using all new TA rings in order that they all matched.



As you can see, TA did a nice job hiding the tabs to mount the granny behind the crank spiders.

Andy, I'm interested as well in a Stronglight triplizer. Plan on me being on the pre-order list. I'm pleased you offering this!

rootboy 

This really IS too cool! Very fascinating thread. While not specifically interested in triples, I sure would get on the list for either a Stronglight 37 for the model 93, or the elusive 44 or 45 tooth ring for the 151 BCD Record crank. Great work Andy.

rootboy 

That is beautiful !

Andycapp

I'm outta town for the weekend and will get back to work on this next week. Funny thing is I'm not particularly interested in a triple either but it sounded like a good and desired place to start. One thing at a time and we'll see where this goes. On a side note, bad news for me but good for you guys- While racing in a speed skating meet this morning I crashed and broke my thumb! (still got 3rd overall though!) I only say good for the project 'cause this will keep on the computer a bit more than usual for the next few weeks.
-Andy

LeicaLad 

Whoa! Sorry to hear of the broken thumb. (this thing should have a frown!)

But congrats! on the bronze placement!

Wotan

This thread has grown a bit in the past week.

Annnnnnyyyyyway, the store I work at needed a custom ring and bashguard made. We called Cycle Underground, got a number disconnect, called a few people that know the guy... Got the order placed and about three days later the rings arrived. He's not gone out of business, apparently he's just not good at communicating.

Soooo, if y'all want me to try and organise something, let me know. I think the prices will be around $60-65 per ring or bashguard (will check for sure tomorrow). And then there's postage from Australia, which is very expensive! Let me know.