Had a bike in the shop for an insurance quote as the owner had been knocked off by a car and the bike had been written off.
We had just got the go ahead to scrap the rest of the bike and though the forks appeared ok, we thought it best they be scrapped too. We put the forks in a vice and slowly squeezed the legs together until they went with quite a lot of force and a bloody loud band.
What was inside was quite a surprise!!!

ikea fork?

http://www.ikeabikeforks.com

http://www.ikeabikeforks.com is unavailable or may not exist.

Damn!

druidh – Member
http://www.ikeabikeforks.com is unavailable or may not exist.
Damn!

My work here is done.

I think you’ll find that dowels/random lumps of wood are used to locate many an item when laying it up for carbon wrapping/laminating, carbon fibre is nothing more than posh fibreglass in my opinion. (Ex fibreglass laminator/carbon laminator and mould maker back in 97-98) – i used to make train fronts , bus fronts, those wee green powered street sweeper things all out of fibreglass, and a few exotic items with carbon fibre laminate as well.

Personally i’d not have a carbon fibre bike frame, although that is more to do with the fact i think it is overpriced and massively hyped up with regard to how little it costs to build a frame of it rather than structural reasons – give me good quality steel tubing or Ti tubing any day, that takes skill to form/ mitre and weld correctly.

But costs a similar amount, weighs more and breaks as easily?

Good for you.

I’ll take my ‘easy to make’ frame cheers!

http://www.ikeabikeforks.com is unavailable or may not exist

http://www.alsforkbikes is where it’s at

wood core skis, anyone ?

balsa core I’m guessing. At least it’s biodegradable compared to the more expensive alternatives 😀

I wooden of thought that wood been in there.

I guess they have to stick the molds together with something, won’t have been structural, although I guess the fact it failed there indicates that’s where two parts of the mold met?

give me good quality steel tubing or Ti tubing any day, that takes skill to form/ mitre and weld correctly.

Which is an odd statement seeing as there must be as many ways of joining metal tubes, which one is ‘correct’?

The clue was “weld correctly”, i could just as easily have said ‘braze’.

Any idiot can weld or melt bits of metal together but to do a single pass tig weld on steel tubing such as Columbus Spirit with a wall thickness of .5mm or True Temper S3 with a similar wall thickness without variation in speed or distance from the tubing surface nor overheat any one area takes what i consider to be a considerable amount of skill and dexterity, something sorely missing from wrapping carbon sheets round a mould, applying adhesive – placing in a vacuum former and punting them out at a cost price of way less than £100 for a relatively high end frameset/bike that retails at £2k+

You can build a perfectly strong compact geometry road frame out of True Temper S3 tubing that will weigh anything from 2.2lbs to 3lbs, and i guarantee it will ride better than an equivalent carbon frame, of course “ride better” is a purely subjective term but spend 100miles on a top-end carbon frame and then 100miles on a top-end steel frame and post back on this thread, i know what i like and prefer so if others prefer carbon then that’s entirely valid for them – just don’t go and think that carbon is the be-all and end all of frame design no matter what the marketing dept tell you.

14lbs steel frame road bike.

p

what’s the fork made of on that steel road bike? Looks chunky and suspiciously cabon-like 😉

and $2,699 for the frame…Light, strong, che..oh no looks like the ‘chose 2’ rules comes in again. 😀

I do like steel frames, don’t get me wrong. But bare in mind that carbon frames are often made to be stiff for maximum efficiency so this is why you might not have got on with them. Carbon just gives you a lot more opportunity than steel to optimise and costs can only come down while steel frames are either expensive due to the need for highly skilled labour or due to niche-tax.

Sure is andyl, like i said carbon is not the be-all and end-all of frame design, it does have it’s uses though.

Carbon is touted as the ultimate frame material because it is so cheap to produce frames in mass quantities, it does have it’s uses for fancy suspension frames with convoluted pivot designs etc but why have a convoluted design in the first place, give me a steel framed simple pivot designed Cotic Rocket any day 😉 .

Yeah, keith had it right eh?, all those years ago and we still use his words today.

My main bugbear is that folk consider their carbon frame to be the ultimate high-end material, whereas it costs very little to produce and the big bike manufacturers are basically taking the piss out of consumers with an often 700%+ markup on frames – it’s not on. I don’t like to see folk get ripped off, that’s my main gripe, but if folk buy cheap carbon frames then crack on – enjoy them as they can be good value (on-one?) and perhaps the larger manufacturers will get a slap in the face.

You can build a perfectly strong compact geometry road frame out of True Temper S3 tubing that will weigh anything from 2.2lbs to 3lbs, and i guarantee it will ride better than an equivalent carbon frame, of course “ride better” is a purely subjective term but spend 100miles on a top-end carbon frame and then 100miles on a top-end steel frame and post back on this thread, i know what i like and prefer so if others prefer carbon then that’s entirely valid for them – just don’t go and think that carbon is the be-all and end all of frame design no matter what the marketing dept tell you.

I dunno, I’ve got an aluminum CAAD road bike and a couple of reynolds steel ones, I’ve done more centuries on the canondale than the steel bikes put together! And they say aluminuum is the harsh material! The main drawback of the steel frames is cornering, they’re ‘stiff enough’ but not quite the ‘cornering on-rails’ you get with good alu or carbon frames.

don’t forget the Rocket has a chunk of aluminium at the back as steel was not right for that part – yuck, horrible material! A bit of carbon would be much better 😉

It’s not just the cost potential that is the big benefit with carbon it’s the optimisation, the cost benefit comes from development of the manufacturing to enable cheaper production. With metals you are pretty much limited to equal properties in all directions. With composites you choose which directions you want strength and stiffness in the material as well as the structural design. The problem with bike frames is they are so simple that the benefits don’t always stand out so much and then add the niche/purist/etc people who stick to steel/titanium etc.

Yeah, i concede the rocket has an alloy arse on it…..i’m not really an arse man so i don’t mind it all that much 😀

I guess some steel frames may appear squirrely under hard cornering but i’ve never experienced that but it’s a valid point and i may as well hold my hand up here and bow my head whilst backing away slowly and say i just do not like the look of any hydroformed alloy tubing nor swoopy carbon framed bikes in the slightest, not even the ibis’s we build up in the shop, a bike should look like a bike, not some hydroformed shitting two legged mongrel.

I’m a niche purist rider….phew…..i feel much better for coming out 😀 , cheers andyl

I’m getting a kicking here eh?

No, I agree with you – but I would say that, I spent all of today filet-brazing some silly thin steel tubes into a frame 🙂

I like steel because it’s bodgable. Want a cable stop in a different place? No problem – heat it up and the old one will fall off, a bit of silver solder and a new one is on. Got a 50-year-old frame that’s rusted through the seat tube? Just braze a new one in. It’s almost infinitely repairable and modifiable. Carbon or alu, if it breaks you chuck it in the bin – for me that doesn’t sit nicely with cycling’s environmental credentials.

i just do not like the look of any hydroformed alloy tubing nor swoopy carbon framed bikes in the slightest, not even the ibis’s we build up in the shop, a bike should look like a bike, not some hydroformed shitting two legged mongrel.

I’ve got a Swift, it looks and rides great, but I don’t kid myself that something aluminium or carbon wouldn’t be better (be it lighter, comfier, stiffer). It certainly has a “je ne sais quoi” factor, but i don’t think it’s measurably better.

And top of the line steel frames are £1000+. That’s as much as most mid to high range carbon frames (and lower to mid range carbon bikes!). For a bike design that’s not changed for well over a hundred years apart from an evolution of material technology. And even then I’m not sure the tubeset actually costs more than the £100 you were quoting for the carbon. Compare that to the amount of R&D that goes into most carbon frames? As for the skills involved in manufacturing, whilst welding and brazing (preferably done by and old man, in cahart dennim, with a bit of a beard, with grease on his arms……mmmmmmm………..I’m off for a lie down) certainly look cooler than some chinese ladies in a clean room laying up carbon i’d not say either is particularly more skilled than the other.

Well, I’ve been building steel frames for over 15 years, and I still have a lot to learn – how long does it take to learn to lay up a carbon frame?

It’s simple economics and economies of scale. Aluminium frames took off not because they were lighter – they often weren’t – but because aluminium tubing of a given strength is much thicker, so easier to weld. Learning to braze or weld 0.5mm steel takes a long time, learning to weld 3mm aluminium is quite a bit faster. The initial costs are higher – especially once you get on to hydro forming and carbon – but once you’ve invested in the tooling the unit costs are much lower because the labour costs are lower.

There’s a comparable example – mouldings for canoes (and recently faired recumbents). They used to be almost all laid-up fibreglass which is cheap to get started with, but time-consuming. Then when rotation moulding came along, it made a huge difference – your first canoe cost £10,000 because you had to pay for the mould, but your second cost £10.

Aren’t production costs largely irrelevant to anyone but the producers? We can’t buy a high end carbon or steel frame for £100.

The selling costs of high end carbon and high end steel are about the same. The difference between materials costs might be profit for one and labour for the other but I don’t care cos they cost what thay cost to me (and what the market will bear).

As for what’s better? Neither. It’s like the CD vs vinyl debate. Utterly pointless and entirely subjective.

no it’s not vinyl is better 😀

Carbon is the future, all biking gear will be made of plastic soon. Frames, wheels, forks, tyres, socks…

If On One can do a carbon hardtail frame comfortably for £400 then I reckon we might see a FS carbon frame for around a grand next year.

The thing about using glue and string (CFRP) is that until the glue sets it is all a bit too floppy so you need some sort of mould or form: that is where the wooden-dowl and foam-cores come in (in the original post / pictures).

bencooper
CFRP is fixable when it snaps , its just a matter of putting a few more layers of glue and string on it.
http://www.youtube.com/watch?v=1WRDEu1rrcM

http://www.mmsonline.com/articles/getting-to-know-black-aluminum

If you look at Products> Sports and Leisure >Frames and components for racing cycles…
http://www.umeco.com/Products
…you will get some idea of what is available for making a bike frame / fork.

Advanced Composites / Umenco offer training for CFRP manufacturing
http://www.advanced-composites.co.uk/what%20we%20do/motorsport.html

bencooper
CFRP is fixable when it snaps , its just a matter of putting a few more layers of glue and string on it.

Well, yes, but that’s a bodge, it’s not returning it to as-new.

I’d like to know where those folk that think that carbon is so cheap are buying it from. I use a bit at work, and blimey its pricey to buy these days – wet layup or pre-preg. Obviously the big boys are getting it loads cheaper but it is still expensive stuff.

IMO the tricky bit with carbon manufacture is not the manual laying up but the designing involved in putting it in the right place, in the right quantities, in the right orientation. I’ve been luck enough to have the full “if carlsberg did tours” style trip around McLaren’s centre in Woking. The work behind the layup design is unreal. If of course all this goes on in the bike world is debatable.

Like any system that works well in volume manufacture the material costs to the retail costs margin looks daft but that simple analysis belies the R&D and expensive setup and tooling outlay.