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-   -   ~ Campy Nuovo Record on the Simplex dropout * Execution (https://www.bikeforums.net/classic-vintage/789124-campy-nuovo-record-simplex-dropout-execution.html)

rootboy 12-28-11 06:21 PM

~ Campy Nuovo Record on the Simplex dropout * Execution
 
or, the forty year itch.

Warning: lengthy content and many pics. I thought I’d post this description of the process in case anyone wanted to try this at home. If you find this account too wordy, skip to the pics.


When I bought my first good bike, A Peugeot PX-10, in 1971, I had two criteria. It had to be light. And it had to be affordable. The two hundred and fifty bucks was about all I could swing at the time but I was planning a tour of the coast of Washington and Oregon with a friend so I wanted a light bike. I bought the Peugeot and my buddy bought a Gitane Tour de France. Not the best choices perhaps, for fully laden touring, but we wanted lightweight European bikes and couldn’t afford the fancy Italian and English bikes in the shops. The French bikes with their plastic derailleurs served us well but I still coveted those pearly silver Campagnolo derailleurs in the glass case at the bike shop. Those components were the prettiest looking things in the display case and they adorned all the best bikes hanging in the shop. I’ve had a thing for Nuovo Record ever since.

I eventually saved up the $24.50 for a Nuovo Record derailleur, but it was a few more years before I had a bike it would fit on. I never mounted it on my Peugeot, but many guys did back then. As you know, the adaptation involved grinding on the Simplex dropout hanger and tapping out the hole, something that was beyond my abilities back then and against my better judgement even if I could do it. I happily rode that Simplex Criterium for many thousands of miles with no problems, but I was still intrigued by how to fit a Nuovo Record derailleur on to a French bike with a Simplex dropout. In fact, I still am. Last week, forty years later, I decided to tackle the project. I sold that Peugeot long ago but in a fit of nostalgia I purchased a purple Gitane TdF about twenty years ago and it is this bike that has provided the impetus for this project. http://i1227.photobucket.com/albums/...F/Gitane21.jpg

rootboy 12-28-11 06:23 PM

THE GOAL: To adapt a Campagnolo Record derailleur to a Simplex dropout, without altering the dropout hanger. Many old French bikes can be found that show the fix performed back then. Grind a stop into the outer circumference of the hanger and tap the hole to M10 x 1 mm. It got the job done, but it somehow ruined the integrity of the bike I thought. As we know now, it also degrades the collectibility of the these nice old frames. I was determined to come up with a method that wouldn’t harm the bike.

THE CHALLENGES: As you know, the Simplex derailleur is held onto the hanger with a M6 X 1 shouldered bolt with a 5 mm hex drive, from the rear of the dropout. The Campagnolo is attached with a threaded bolt. The adaptation required me to make a new bolt to fit the Campy derailleur but that would accept the Simplex bolt.

It also required some way to stop the derailleur from rotating too far forward, the function provided on the Campy dropout by a notch forged into the dropout and a boss protruding from the upper body of the derailleur. The boss rests against the stop, keeping the derailleur at the required angle. The stop on the Simplex derailleur is provided by a plate attached to the upper body of the unit which it attached to a spring inside the body and which registers against the outside of the hanger with a bent tab built into the stop plate. The rearward motion of the Simplex is governed by the spring in the upper body of the derailleur. The Record has no such spring and is free to rotate freely on its mounting bolt, tension on the chain provided by the spring built into the lower portion of the body which acts against the pulley cages. This is all common knowledge to most of you but I’m describing the construction details in order provide insight into how the modified stop was achieved, in case anyone wants to try this.

But I’m getting ahead of myself. First, I had to make a bolt. Shown here are a few pics of the bolt being constructed on my old Logan 10 inch lathe.
Sorry about the lousy pics.
http://i1227.photobucket.com/albums/...rningbolt1.jpg
http://i1227.photobucket.com/albums/...rningbolt2.jpg
http://i1227.photobucket.com/albums/...rningbolt3.jpg

rootboy 12-28-11 06:24 PM

DISCLAIMERS: Although I have two metal lathes, and a small milling machine, I’m no machinist. I am fairly adept with my woodworking machines and tools, but I’m a complete amateur on metalworking machines. I use them to make parts for custom lamps I make, and because I like old cast iron American home shop machinery.

Nomenclature; I’m going to use terms for various parts which may or not be proper. I aint no expert, just a tinkerer. Hopefully what I’m referring to will be clear enough without providing a glossary.

Also, this type of modification may have been done before, I don’t know.
If it has, it sure would have been nice to know so I wouldn’t have had to re-invent this particular wheel. This project was fun, frustrating and very satisfying but may fall into the category of “this guy has too much time on his hands”, and, as my wife likes to say, might be another example of “painting legs on a snake”. I consider myself to be an expert painter.

MATERIALS: I decided that since I have very little experience turning steel on a lathe, and since this first attempt was to be a prototype, I would use something more forgiving that I had on hand, a piece of nickel silver bar stock and some .062 nickel silver plate. Nickel silver is nothing more than brass alloy with twelve or 18% nickel added. Not the ideal material for the parts but tougher than brass, with added corrosion resistance, and a heck of a lot easier to work with than steel.

****

rootboy 12-28-11 06:27 PM

Making the bolt: The diameter and length of the bolt needed to be very precise. Since the new bolt would bear against the new stop plate, which would in turn be clamped between the bolt and the surface of the dropout hanger, I machined a small shoulder on the end of the bolt to fit the bore through the stop plate. The shoulder serves to register the stop plate to the bolt and is only half the thickness of the plate so it effectively clamps the plate to the derailleur hanger. The bolt was drilled and tapped to M6 X .1 prior to machining.

http://i1227.photobucket.com/albums/...boltfacing.jpg
When the female end of the bolt was completed I cut it off and reversed the part in the lathe to finish the head, a recipe for eccentricity but I managed to
get it fairly well centered again. The head of the bolt provided a challenge. Milling a hex-shaped hole in the head for a 6 mm wrench is beyond my capabilities but since the bolt will be cinched down from the rear there’s no absolute need for a hex hole. Still, it would be nice to have something to hold on to. I wanted to do a straight knurl but could find only cross hatch patterned cutters in my stuff. Somehow the idea of cross hatch pattern on the head of the bolt didn’t seem like it would look right to me. The first bolt has a sort of “self-knurled” head as a result of an accident when during one of many amateur mistakes the work piece “climbed” the cutter, which was set too low, setting up a nearly perfect chatter pattern around the head of the bolt.
What the heck. I left it. I turned a second bolt later, to fine tune the length and diameter a hair and do a head shape more closely representative of the original. I left the head on the second bolt smooth but for a tiny concentric groove. Not enough to hold on to, but it works. I may do another one with fancy indexed cuts in the perimeter. There’s that snake again.
http://i1227.photobucket.com/albums/...ishedbolt2.jpg
http://i1227.photobucket.com/albums/...h/newbolt1.jpg

rootboy 12-28-11 06:28 PM

THE STOP PLATE

The stop plate was very tricky. The idea was to use the stop boss protruding from the rear of the Campy body to register on a notch cut in the plate, with a bent leg like the Simplex plate to register against the outside diameter of the hanger. Easier said than done as those three aspects need to be in precise relationship to each other. It took me four tries. Two of them broke when I heated the alloy to bend the little leg. I ended up using the first one after having initially rejected it because I thought the notch location allowed the derailleur to sit too far forward. So it goes. It’s a prototype and I would like to perhaps mill a plate out of a little thicker material to provide a heavier, more robust stop. Not sure this part will stand up to rigorous use as is, but it works. Subject to further modification.
http://i1227.photobucket.com/albums/...atefitting.jpghttp://i1227.photobucket.com/albums/...teandbolt2.jpghttp://i1227.photobucket.com/albums/...ltinplace1.jpg

rootboy 12-28-11 06:31 PM

THE BOSS


The stop boss on the rear of the derailleur has to be modified slightly to clear the diameter of the Simplex hanger. The pics show me laying out the alteration and using the Dremel to remove a bit from the inside of the boss. http://i1227.photobucket.com/albums/.../stopboss1.jpg
http://i1227.photobucket.com/albums/.../stopboss3.jpg
http://i1227.photobucket.com/albums/.../stopboss4.jpg
http://i1227.photobucket.com/albums/...pbossdone2.jpg
http://i1227.photobucket.com/albums/...pbossdone1.jpg

rootboy 12-28-11 06:32 PM

http://i1227.photobucket.com/albums/...urmounted1.jpg
Time for a road test. The set up works fine on the stand although I do have a little misalignment and vague looseness, but I think the old Pat. ’72 derailleur may just be worn out. All in all I’m pleased with the result.

After that, to make one out of tool steel. Maybe later. Many legs to paint. http://i1227.photobucket.com/albums/...h/newbolt4.jpg

Alan Edwards 12-28-11 06:35 PM

WOW, thats all I can say. I thought I was pushing the envelope fixing old RDs, you are making new parts that never existed. You are da man.

shnibop 12-28-11 06:46 PM

Bravo! excellent work, now patent the parts/design, send it off to Velo-Orange or something for mass production :)

i had a similar idea (if not identical) a while back... but no means of realizing the idea, it got filed away somewhere in the back of my head.

auchencrow 12-28-11 07:18 PM

You're a genius Rootboy.
- And I'm sure the envy of every Simplex-derailluered French-bike-owner the world over.
- Not many would have thought of this, much less realized it.

( Of course, it might have been good if you had done this 40 years sooner for the tour of the coast of Washington and Oregon - but better late than never. ;) )

rootboy 12-28-11 07:44 PM

Thanks guys. It was a real challenge and much blue language ensued, but it came out pretty well. I hope it works under load.
Auchen' , If I had attempted this forty years ago, it would have had to be with an old, corded electric drill, some files and a hammer.
It's been a long time itch, but I didn't scratch it 'til now. ;)

auchencrow 12-28-11 07:57 PM


Originally Posted by rootboy (Post 13649590)
--- If I had attempted this forty years ago, it would have had to be with an old, corded electric drill, some files and a hammer. ...


Like this? :twitchy:

http://i254.photobucket.com/albums/h...exDODrewed.jpg

CV-6 12-28-11 08:14 PM

So when do you go into production?

cudak888 12-28-11 08:15 PM

A standing ovation for Rootboy for coming up with the best solution ever devised in 30 years to solve this issue.

You should be proud of your invention there - you have every right to be.

-Kurt

mkeller234 12-28-11 08:25 PM

Wow, that deserves a standing ovation. Nice work.

LeicaLad 12-28-11 08:29 PM

+1,000. Very, very clever, and an excellent implementation of the concept.

Better yet, very well documented and explained. It really is the best solution ever. I'm afraid to expose my butchered '71 TdF to public eyes, as it was done the old-fashion hacked way.

This is a truly elegant solution. :love:

This thread should be included in the permanent solutions/collections sticky!!!

Congrats!

rootboy 12-28-11 08:38 PM


Originally Posted by cudak888 (Post 13649681)
A standing ovation for Rootboy for coming up with the best solution ever devised in 30 years to solve this issue.

You should be proud of your invention there - you have every right to be.

-Kurt

Thank you so much Kurt. And Mkeller234 and LeicaLad. That's high praise indeed. Thanks.

Chris W. 12-28-11 08:56 PM

Very cool! Very enjoyable read too!
Thank you for sharing ;)

Cheers,
Chris

Henry III 12-28-11 08:59 PM

Dang that's pretty impressive if I do say so myself. Well done Rootboy! So how does it shift to the composite Simplex derailleur. Are you going to put on a matching front derailleur and shifters or just do the rear NR derailleur?

noglider 12-28-11 09:05 PM

You da man.

rootboy 12-28-11 09:12 PM


Originally Posted by Henry III (Post 13649802)
Dang that's pretty impressive if I do say so myself. Well done Rootboy! So how does it shift to the composite Simplex derailleur. Are you going to put on a matching front derailleur and shifters or just do the rear NR derailleur?

Thank you Henry III. Already got the NR front and shifters mounted. Pics will follow in another thread when I get the bar wraps done.

Chris_in_Miami 12-28-11 09:14 PM

Very nice work rootboy! I've been eyeing old lathes and mills for a while now, and this thread is really chipping away at my self-control ;)

rootboy 12-28-11 09:19 PM


Originally Posted by CV-6 (Post 13649677)
So when do you go into production?

That's a good question CV-6. I had thought about it, in case anyone asked. There's a few variables. First, I have to make sure this thing works. I have no doubt it will but want to test it a bit. Secondly, I'm thinking steel would be the best option for long term service, but that presents a problem. I cut out the stop plate on my woodworking band saw. Not possible with steel. Not sure how I'd tackle that without a metal cutting saw of some sort. Hack saw and grinder? Ugh. Plus, this required a bit of hand fitting. Most Nuovo Record derailleurs are built to precise enough specs, and a person could certainly modify their own derailleur with a Dremel. Pretty easy. The outside diameter of the Simplex dropout might inject some inconsistencies but stop plate built to fit mine might work on others. Still brainstorming this. Thanks.

Michael Angelo 12-28-11 09:39 PM

That exemplifies the word "Mechanic" in every sense. Very good work.

yuyax 12-28-11 10:08 PM

1 Attachment(s)
Rootboy! That's great work.

The 'stop plate' you made... I bet I am not the only one looking for a Mavic SSC rear derailleur stop plate. I and many others will be willing to buy them off you if you decide to go into production.

This ebay auction shows the washer/plate: http://www.ebay.com/itm/Vintage-Mavi...item27c18a7fa4

And here:

http://bikeforums.net/attachment.php...hmentid=231820

And you could probable sell them on Ebay also... What do you say :) ?


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