Fat Chance 1992 Yo Eddy Rebuild

[WD Pro]

I see that the controversy has started again !

It’s interesting to see how strong opinions are (both ways) about the modifications

With regards handing out :facepalm:’s, the only :facepalm: that I think is required is for the folk that appear to be genuinely wound up / stressed out about what some guy is doing to an old yo frame that’s seen a hard life and has already been subject to some odd repairs … ;-)

The mods I am doing aren’t the first time they have been done on a yo, neither will they be the last – A disk braked yo even managed to find its way into the ‘30 years of Fat official party by Chris Chance & Wendyll Behrend’ and get a mention in the write up, without any negativity ;-)

Anyhow, back onto the build

In preparation for soldering on the cable stops, brake pipe mounts, repairing the chain suck and adding the anti chain suck mounts, I had been wondering about the effects of heat on the ‘sealed’ tubes and if they originally had a vent somewhere that was sealed at the end of manufacture / before painting etc

I asked a few questions and got this very helpful response from Scott Bengtson over on FatCogs (User ID : I-ROBOT), Scott’s avatar photo reads “Chief Welder, Fat City Cycles, Somerville, MA’ … :shock:

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Hello WD

It is virtually certain that I welded your seat tab, pizootie tab (the little seat stay gusset plate) small bridge tubes, brake cable bridge, brake mounts, and rear dropouts. I welded nearly all of them for the Yo's made in Somerville.

I welded quite a few of the Yo main triangles and most of the Fat titaniums and road frames. I did not weld many of the forks however

We did not use vent holes in the tubes. On a rare occasion a weld would pop as I went to seal it since the heat would build air pressure in the tube. Most of the time I would weld almost all the way around, let it cool completely and then go back and weld the last little part to finish it. I would always do that in an area that could be easily fixed if it did pop.

If I did have to use a vent hole (more common on repairs), I would drill a 1mm hole somewhere around the middle of the tube and usually toward the inside or bottom depending on which tube it was, finish the repair or weld whatever the operation was and then I would use a quick silver braze to seal the hole and then sand it smooth so it would not show.

I was perhaps the only American Welding Society Certified Welding Inspector and degreed welding engineer who worked welding bike frames in those days. There could have been others working at the big guys like Trek or Cannondale but I never knew of any personally

Thanks for your interest!

Scott

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Bearing this in mind, I propose to solder the top tube cable stops, top tube and seat stay brake pipe mounts on without a vent hole (The top tube has already seen heat with me removing the cable stops – no detrimental effects).

I will use a vent hole for the chain suck repair and the anti chain suck mounts – my logic being that this tube will see the most heat and it only has a small internal area to absorb the build in pressure.

As I am not sure on the ideal hole position, I will put the vent hole in the end of the stay in the spot where most vented frames already have a hole – my logic being if it was a bad place it wouldn’t be so common ! I will fill the hole as the last operation once everything else has fully cooled.

I just need to fully strip the frame now which is being a bit of a pain, the finish seems quite resilient to Nitromors – it takes ages and hardly does anything ? ! It worked quite well on the crank and forks … ? :-(

The new decals were dispatched from the states a couple of days ago now so I should have them soon

WD

 

[CTK]

Great project again WD- I am all for updating old frames.

However I cant understand how on one hand you are removing the seattube to be true to the original and on the other are adding a disc mount! Seems illogical and an unnecessary expense.

BTW A vote here against adding the holes for the chainsuck device.

 

[unkleGsif]

Great project again WD- I am all for updating old frames.

However I cant understand how on one hand you are removing the seattube to be true to the original and on the other are adding a disc mount! Seems illogical and an unnecessary expense.....

I thought it was just the geek in him, wanting all the frame joins to be uniformly brazed, rather than a mix of braze and the welded repair......

Anyhoo.... this is an awesome project, and the results will 100% be up to his usual impeccable standards



G

 

[brocklanders023]

You had a priceless frame,

Not really though, is it, as nice as Yo's are (I'm a confirmed Yo fan btw).

Enjoying the thread WD, keep it up.

Must have a visit to Fat Cogs again soon..

 

[Jamis Diablo]

From what I have picked up, Fat's ethos was always to do what they wanted and they would spec the bikes however the customer wanted with regards frame features / braze on's and paint etc. I don't see how my build has changed that mentality much, if at all ... ?

WD

Amen!
You do a very nice job with this frame.
I just read the whole topic and had a nice hour of reading.

 

[WD Pro]

I thought it was just the geek in him

You are right ...

I have never been overly excited with brazed joints, not sure why ?

Add them onto a tig'd frame and it's wrong, just doesn’t sit right with me :?

Add into the mix that I don’t think they are particularly neat brazed joints (I will try and get some pictures to highlight what I mean) and it's just to much for my OCD …

I have allays liked neat welds, not sure why, but it is important to me and I like the look and appreciate the work / skill to create them (I have C&G in mig / mild steel and tig / ally).

Before I traded this frame I did some research and came across pictures of a yo frame that had been repaired / seat tube replaced (same frame has just sold on here). I was very impressed with the quality of the repair, judge for yourself :





Needless to say this is the frame builder who's waiting list I am on …

WD

 

[WD Pro]

Hi Eddy …



Bye Eddy …







The local auto body paint suppliers came to the rescue with some paint stripper that actually works on the frame

I only had 10 mins to try it so it's not finished yet, but at least I now know I can get through the paint

WD

 

[WD Pro]

I got a bit of spare time today so managed to strip most of the front triangle

I found a few bits that needed sorting but generally everything is looking great

The head tube area had an 'extra' layer of cream primer under the paint, I haven't found this anywhere else (yet ...). I didn't know why at first, but in hindsight, I suspect it was filler primer to hide the cable rub - only one of these had rubbed the latest paint job, the others were invisible so the filler primer must work ! :

This I could see through the paint (the dimple) :

So it was expected and already on the list of things to fix - not sure what it is ?

This is a bit weird :

But an easy fix.

I had a little bit more time than expected so managed to fix two of the above before packing away.

I used the same rods that I used on the bear valley :

I forgot to take a picture of this immediately after brazing so this is part prepped :

The gusset :

And after :

It was actually quite hard to get the camera to pick it out (took about 20 shots to capture the above !) and I gave up trying to capture the down tube repair - it's that small it's difficult to see with the naked eye now it's dressed

The inside of the head tube and bottom bracket are really good and clean - no rust / pitting etc. If I can get a good shot I will because the evenness of the weld penetration inside the head tube is remarkable

More coming soon ;-)

WD

 

[shutter]

Very cool! You have inspired me to do some of my own frame work =)

Ill do some practice on junky frames first though =)

I have a fork with a small dint in the side and would really like to learn how to fill dints like that with brass, it would also be cool to learn how to filet braze... Mostly for cosmetic though... Filet braze over Tig welds to give it a more smooth look (and add a couple pounds in the process hahaha)

 

[WD Pro]

Hi,

Thanks for the comments

My first go at brazing was also on forks, the ones off my Marin. If you check out my bear valley thread there are quite a few more photos etc on there (shortcut to pages 19 & 20) that might help.

There will be quite a bit more brazing to do on the Yo but I am a bit concerned that my torch won’t be hot enough :? I also need to get some thin rods and a paste flux – I think it will be a lot easier to see what is going on when adding the pipe mounts etc ?

WD