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-   -   Il Gregario - a custom project (https://www.bikeforums.net/classic-vintage/1031615-il-gregario-custom-project.html)

iab 09-23-15 05:58 PM

Il Gregario - a custom project
 
About half of the time I spend on a bike is commuting. Yet my commuter is my cheapest and ugliest bike. I really do like the my C15 though.

Anyhow, I have decided to go custom for the commuter. And when I say custom, I mean full on custom. In addition to the geometry, I plan on designing and fabricating custom stem, bars, levers, grips, carrier, electrical/lighting system, rear rack, panniers, tool case, lugs, and perhaps a lock and pedals.

Why C&V? Well, I post here. Also, everything will be a ode to the past. Or, if you like, a ripoff of old stuff made out of new stuff.

I'll keep this ongoing but I expect a finished product in 2-5 years, so don't expect quick progress.

Anyhow, I have modeled the lugs and printed plastic prototypes. Not bad for a first swag. Don't get me wrong, there is work to be done on proportion and there are some surfacing issues, but it is a good start. They are my ode (or ripoff if you prefer) of the Gloria fleur de lis lug. Just takes advantage of modern manufacturing methods. While I certainly could do a lost wax when the time comes, since I will be making only one set, it will probably be cost advantageous to print them out of stainless.

Please excuse the low quality pictures. Also, the tubing pictured is 40# Hammermill.


https://farm1.staticflickr.com/727/2...f55ac224_h.jpgLugs01 by iabisdb, on Flickr

https://farm1.staticflickr.com/653/2...7f80ef43_h.jpgLugs02 by iabisdb, on Flickr

https://farm1.staticflickr.com/758/2...6fe590b3_h.jpgLugs03 by iabisdb, on Flickr

https://farm6.staticflickr.com/5700/...8b1d6060_h.jpgLugs05 by iabisdb, on Flickr

https://farm1.staticflickr.com/566/2...36106c11_h.jpgLugs07 by iabisdb, on Flickr

https://farm6.staticflickr.com/5672/...5fc87f3a_h.jpgLugs08 by iabisdb, on Flickr

Sir_Name 09-23-15 06:09 PM

Well that sounds like a fun project. What do you use for modeling and printing?

KonAaron Snake 09-23-15 06:22 PM

I'm going to enjoy this for 2-5 years. I do feel badly for the builder you work with ;)

iab 09-23-15 06:42 PM

Rhino and Solidworks for the modeling. Plastic is Accura Clear, SLA process. Nice resolution, you can sand off the ridges with 400 grit. I use a local place. The metal will be SLS, which the local house doesn't do. I'll try their recommendation and Fineline for quotes.

The builder will be a problem. While I am interested in their expertise in craft, I am not interested in their design expertise. I will listen, but I want what I want and won't compromise on certain things. To make it more difficult, I am planning on a stainless steel tubing set which limits the builders. But I figure it will be at least a year before I start that process.

Chrome Molly 09-23-15 06:54 PM

I know a guy...

ChicAgo steel 09-23-15 06:59 PM

The line of folks demanding to own this bike will grow longer as this process matures.
So let me first, and where do I send my down stroke?

KonAaron Snake 09-23-15 07:19 PM


Originally Posted by iab (Post 18189273)
Rhino and Solidworks for the modeling. Plastic is Accura Clear, SLA process. Nice resolution, you can sand off the ridges with 400 grit. I use a local place. The metal will be SLS, which the local house doesn't do. I'll try their recommendation and Fineline for quotes.

The builder will be a problem. While I am interested in their expertise in craft, I am not interested in their design expertise. I will listen, but I want what I want and won't compromise on certain things. To make it more difficult, I am planning on a stainless steel tubing set which limits the builders. But I figure it will be at least a year before I start that process.

Most builders are going to have some opinions on the design. I think this is going to be...interesting. When I think stainless, I think waterford...I'd likely start there.

smontanaro 09-23-15 07:31 PM

Dave Wages?

iab 09-23-15 07:42 PM


Originally Posted by Chrome Molly (Post 18189301)
I know a guy...

If I had to choose right now, he'd probably be my guy. But there are these fellows I know who need a bit more experience. Maybe they will have it when I am ready.

gomango 09-23-15 07:44 PM


Originally Posted by Chrome Molly (Post 18189301)
I know a guy...

Yes sir.

Watching this closely.

OTS 09-23-15 07:57 PM

Yes, yes, yes

I know this will be worth the wait and the watch.

Italuminium 09-24-15 02:02 AM

subscribed, great project!

randyjawa 09-24-15 04:01 AM

iab is one of the most interesting contributors to this forum, in my opinion. I love his old school steel and this new project should prove to be remarkable. I too will keep an eye out for build progress. But I cannot help but wonder one thing..?

Are you really going to use such a nice bicycle for commuting? Are you not concerned with theft, or bad weather, or anything else that might confront the bicycle, while it is parked and you are away from it?

And, I used to spend most of my riding time on lesser bicycles, also. Even the Peugeot Course I put 3000k on in Jamaica was nice, but nothing special. However, this year's trip to the island will see me riding something a great deal more worthwhile - my Bianchi Pro Team Race...

iab 09-24-15 06:07 AM

Well, on first blush, that is a good question Randy. Currently, as I wrote, my commuter is my cheapest bike. While I don't intentionally abuse the bike, I will put it away wet. It does not get the level of maintenance of my "good" bikes. Once a month I'll wipe the chain, give it some lube and call it a day.

But that is what makes it a challenging design problem. How do you make an "abused" item nice? As revealed thus far, the stainless steel tubing is a material that can get "forgotten". I have other ideas that will be shown as time allows. This bike will be a commuter/grocery getter/toodling around town bike and hopefully the design will reflect that.

rhm 09-24-15 06:18 AM

I like the sculptural aspects of the lugs. I don't think I've seen that before.

I have the same problem: about half of all my time on bicycles is spent commuting, and when I commute on a "nice" bike, people ask why I'd relegate nice bike to the abuse of commuting. Well... I'd rather ride a bike I like, you know? It is true, that my commuter bike, whatever it is, tends to fall behind on maintenance issues. When I come out of the house at 4:45 AM and grab a bike, if the lights come on when the wheels turn, and the brakes will stop me, I will ride it. And when I get home in the evening, I forget all about it until morning. Whatever this 'commuter' bike is, it has to be tough, but I still want to enjoy riding it. So the idea of a custom commuter, that satisfies the desire for riding a nice bike while not suffering from the ravages of salt and grit, appeals.

KonAaron Snake 09-24-15 07:34 AM

That's why my main commuter is a MTB with a ti frame ;)

gaucho777 09-24-15 01:26 PM

I like the look of the lug design, but I wonder about the bulkiness of the lugs. Could they be thinned out a little?

"The need for uniform thickness at the frame joint is important because overheating of the thin section tubing can occur if the lugs are on the heavy side.Thinning the lug and cutting it to make an attractive design has two technical benefits. First, it lightens the lug and allows brazing or silver soldering of the joint to be done at a lower temperature, with less danger of overheating the thin-walled tube. Second, the flow of the silver solder can be seen more easily with a design in the lug that gives a few "windows" to see into the joint." -Art Stump (Source, a good read: Art Stump, on handcut lugs)

Steve Rex is another builder worth considering. This is an example of one of his stainless bikes (polished stainless, not chromed, lugs):

http://i850.photobucket.com/albums/a...o/IMG_4029.jpg

http://i850.photobucket.com/albums/a...o/IMG_4032.jpg

http://i850.photobucket.com/albums/a...o/IMG_4031.jpg

I struggle with this "nice commuter" bike conundrum as well. I use a ~44-year-old Reynolds 531-framed bike with mostly period-correct Campagnolo parts. To us bike nerds it's a nice bike, but it can be easily overlooked in a crowded bike rack. The Campagnolo parts are reliable and work well. Save for a broken Lyotard pedal axle, it's given me no trouble. Some people might consider the bike too collectable to be used as a commuter. On the other hand, others accustomed to modern tech might consider it not nice enough to ride on a daily basis (no brifters, 5-speed freewheel, etc.). In the end, it's faster than most people realize and I get a lot of enjoyment out of it and I'm proud to have put some patina back on it. If I were to get a custom bike now and with an eye to the future, it would be in the randonneuring vein--fast and nimble enough to take on weekend rides, but also incorporating utilitarian aspects such as eyelets, fender mounts, and ample tire clearance so it might double as a commuter, gravel grinder, grocery getter. But then of course I'd equip it with high-end parts and worry about it getting dinged or stolen.

iab 09-24-15 05:07 PM


Originally Posted by gaucho777 (Post 18191486)
I like the look of the lug design, but I wonder about the bulkiness of the lugs.

I wonder about that too. Currently, they run 2mm at the "ridge" and taper to 1mm at the edges. The bulk of each lug is at 1mm.

Wall thickness of XCR tubing at the lug is 0.7mm. So while thickness is not that far off, it certainly can be adjusted. I would most definitely consult that fact with the builder before I print the the lug. Changing the solid model only requires a few clicks of the mouse.

I could also probably keep the sculptural aspect of the lugs using a 1mm-1.5mm range instead of the 1mm-2mm range. But I want to keep something. I'd like to change the "flatness" of your typical lug.

squirtdad 09-24-15 05:15 PM

Maybe IAB could go all the way and build the whole bike :) very cool project

iab 09-24-15 05:40 PM

Considering the cost of the tubing set and printing the lugs and my complete lack of brazing experience (although with some practice, I could possible weld it), I am not willing to take the monetary risk.

3speedslow 09-25-15 09:40 AM

Stunned to think of the level of attention this commuter bike will get.

Awesome indeed. I will follow this as well.

I feel like a caveman, but happy.

iab 10-01-15 06:46 PM

Found out a few things.

Found out lug wall thickness should be 1.2mm.

Found out [MENTION=175208]gaucho777[/MENTION] has an excellent eye. I thought for sure the thickness at the ridge was 2mm but in reality it was 3mm.

Found out 3D stainless printing for just 1 of each of the 3 lugs is $5000. Yikes.

So I am currently obtaining quotes for investment casting. I changed the wall thickness from 1mm to 1.2mm. And the ridge height is now 2mm, 0.8mm taller than the thickness. I also changed some proportions and added a bevel instead of straight walls for the triangular inset. I'm also too cheap and lazy to print the new refined parts. All you get are images from my modeling program.

https://farm1.staticflickr.com/696/2...82c03a46_o.jpgLugs09 by iabisdb, on Flickr

https://farm6.staticflickr.com/5825/...82d19f89_o.jpgLugs10 by iabisdb, on Flickr

https://farm6.staticflickr.com/5669/...de27d7f9_o.jpgLugs11 by iabisdb, on Flickr

Flog00 10-01-15 07:32 PM

Do you expect that the builder will put his name on the bike? Or is he just the labor?

If I were a builder, and my name would be on the bike, I would want a large measure of control over the final product.

iab 10-02-15 05:45 AM

Yes. A builder with a large ego won't work.

But no matter how you cut it, they are getting paid for a service. Some people may want their "vision". I don't.

Any particular reason why I should?

rhm 10-02-15 06:06 AM

I'm somewhat surprised by the price of the 3D printed lugs.

I've had a few things 3D printed in a material they call "stainless steel" and they were pretty reasonable. Much smaller, to be sure: a couple saddle badges (about $10) and one part for a Resilion brake (about $25). I had them "printed" by Shapeways.
According to the Shapeways website,
"Steel is printed by depositing a liquid binder onto a bed of steel powder one layer at a time. The product is then removed from the printer and infused with bronze. While the product is being transferred from the printer to the infusion chamber, it exists in a delicate "green state" which does not support interlocking parts." I'm not sure I'd call that "steel" but they do. So I guess your lugs would be "printed" by a different process? When Shapeways "prints" brass or bronze, they actually print a wax model that is then used for a lost wax casting.

I wonder if a "green state" print of a lug would be sturdy enough to be assembled into a bicycle frame. Brazing would (could?) then infuse the brass into the steel. I suspect this process, if it would work at all, would be different enough from conventional brazing that you might as well just learn to do it yourself.


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