KARMA Ti frame - Photo's added (and consolation prizes too)

[AR-CoolC]

Thanks for the offer, but can you remove my name from the list please?

The chap I had lined up to weld this isn't confident after seeing the pictures.

Cheers

 

[mynchiboy]

I'll have a number please, just finally got around to reading this

 

[We_are_Stevo]

Everyone is welcome to chuck their hat in the ring if they are interested...

As a Post Script to the above spat with Rody over the suitability of this frame for repair/re-use I should perhaps say that this the typical difference of opinion between a passionate craftsman (Rodys work speaks for itself, his frames are works of art...) who takes offence when he sees something 'substandard' for want of a better word, and an engineer who looks at something and knows he can make it work again...

Rody fell into the trap of giving the boring 'craftsmans' explanation of 'why' a repair shouldn't be attempted unless it was done 'correctly...' because he is passionate about his craft in exactly the same way I was when I was in the photographic industry pre-digital, so I really can appreciate his point of view.

Also, I was taught engineering by the type of people in brown coats who had been doing the same thing their whole lives and probably still thought they could get better but who we looked up to as 'gods...' They were stern tutors who demanded respect but would say 'I am here to teach you lot the right way to do it, what you do with that knowledge is up to you..'

My attitude has always been 'I have the knowledge, that knowledge tells me this can't be done - but I'm going to try anyway... Hey, waddya know - it works!'

Therefore I would repair/have this frame repaired and not worry about it because it CAN be done - but it doesn't HAVE to be a textbook repair to work...

 

[trickylad]

wow.

Kan
A
Raffle ticket ave
My name on it
Ave it!

count me in. It's so lovely i'd ride it tomorrow

 

[We_are_Stevo]

Absolutely...

Thinks...'Gonna have to start writing out my lollipop sticks!'

 

[paddlingpool]

Could I have a number please

 

[john]

Wow, that is indeed an amazingly kind gesture Steve and certainly indicates the strength of the community we have here on retrobike

I'm going to move this over to the Classifieds where it perhaps better fits. At this rate we'll need a 'karma' forum!

One thing I would suggest is that any potential entrant / winner take heed of Rody's word included below. I really think Steve should be giving this away either as a wall hanger or on the understanding it should be taken to a reputable ti frame shop (of whom Enigma is the only I can think of in the UK) for proper analysis and repair. From the way the frame has failed and been previously repaired I really don't think this is one to take to your mate Barry with a MIG who has a lock up round the back of the railway station.

From the few pictures posted, it is clear there are multiple issues with this frame;

The first being the torsional failure extending from the bb area up and around the bottom of the down tube, terminating on the drive side. This fatigue failure should have never been welded along the failure line, as torsional propagation cracks will continue past the end weld. The proper repair for this failure is the replacement of the down tube.

The fractures at the seat tube/bottom bracket are typical for the manufacturer along many of their clients lines. Poor miters and insufficient purge have been evidence in the years following, an unfortunate result of their rush to jump into the Ti market during the 90's. While this area can be easily repaired, the contaminated welds on your frame indicate that it was not done correctly. These oxidized welds will fail again in time due to the excessive heat and poor purge coverage.

The dropout in question suffers most from a poor design, placing all the torsional stress of the dropout on a hinged end plate. It broke at the weld as the design does not transfer the stress to the strongest point of the joint. The interior of the tube shows high oxidation levels...from a repair standpoint it will be very difficult to properly clean this section before welding. The correct way to repair the dropout would be to remove it fully from both stays, bead blast the interior of the tubes, grind away the existing weld, and extend a custom machined insert from the inside of the chain stay to attach more fully to the surface area of the dropout. This will allow for greater torsional rigidity and longer dropout life in cyclic stress loads.

Could the frame be made safe again? Yes. Replace the DT, BB and modify the dropouts as noted.

 

[firestaffman]

Number please

Dibs on a number please!
Cheers

 

[We_are_Stevo]

Wow, that is indeed an amazingly kind gesture Steve and certainly indicates the strength of the community we have here on retrobike

I'm going to move this over to the Classifieds where it perhaps better fits. At this rate we'll need a 'karma' forum!

One thing I would suggest is that any potential entrant / winner take heed of Rody. I really think Steve should be giving this away either as a wall hanger or on the understanding it should be taken to a reputable ti frame shop (of whom Enigma is the only I can think of in the UK) for proper analysis and repair. From the way the frame has failed and been previously repaired I really don't think this is one to take to your mate Barry with a MIG who has a lock up round the back of the railway station.

Wise words and sound advice from the Guv'nor as ever...

But with regard to the repair I would trust an aircraft technician over a frame builder every time - if they can weld wings onto aeroplanes I reckon they can repair a bicycle frame, and probably for a lot less...

Like many skilled professions, frame builders hark back to a bygone age when everything was a dark art in a closed shop (yeah, ok, that IS a sweeping generalisation...) where only THEY knew how to do something 'properly...'

The POTM thread on here is a perfect example of how that really is no longer the case - never was there a snootier profession that being a 'Professional Photographer' (...and I should know, for I was!) but virtually anyone with a digital camera and a photo-editing suite on their PC can now produce a picture that would have once cost them hundreds of pounds to commission...

There are simply loads of engineering firms in the Yellow Pages (for example) who manufacture all manner of things in Ti - and many of them are amenable to a request to 'borrow' their skills for little more than tea money...

Another photo' to show the joint 'closed' so you can see there is no material 'missing...'

A very simple repair indeed... As for the assertions that the tubes should be replaced, I beg to differ;

If I wanted to ensure that the BB area was as strong as it could possibly be I would cut the down/seat tubes, insert a slightly smaller diameter tube (push it into the upper part of the tube then let it drop back down to the BB when you close the join) to over lap the damaged/cut section, drill it, pin it and then weld up the joins - job done...

 

[drystonepaul]

With respect I think that you're missing the point of Rody's advice on what constitutes a safe and quality repair.

Sure you could add extra inserts, pins, plates, gussets, welds and whatever else to make the frame virtually indestructible, but at the same time you could double it's weight and kill any ride characteristics.

There is a big difference between aircraft engineering and bicycle engineering, and while I wouldn't doubt the skills, experience and knowledge of an expert in that specific area, I would also hesitate to undermine the input of somebody as skilled, experienced and knowledgeable as Rody is in his.