Self Build Bamboo Bike Frame Kit Build Thread

[chriswoody]

Thanks @QFour I'd seen a couple of builds on instructables, but not that one. He uses some interesting techniques to build that trike and the end result is really striking, I love the colouring of the Bamboo.

 

[gaijintendo]

Just spotted this, might be of vague interest:
https://www.reddit.com/r/bustedcarbon/comments/5wsnpy/my_bamboo_and_carbon_bike_bambroke_today/
Fairly scruffy looking carbon taping, but seemingly rode fine until... that point.

 

[buzzy-beans]

Just spotted this, might be of vague interest:
https://www.reddit.com/r/bustedcarbon/comments/5wsnpy/my_bamboo_and_carbon_bike_bambroke_today/
Fairly scruffy looking carbon taping, but seemingly rode fine until... that point.

And then OUCH!!

 

[chriswoody]

Mmm interesting link. Seems from the comments that he failed to wrap the carbon fibre properly and it ultimately failed. Luckily I'll be using hemp on mine, a little easier for beginners like me.

So on the subject of mistakes, my last update was all about my mistake with making the seat stays too close together and not leaving enough clearance for the wheel. So I looked at various ways I could rectify the situation. Sadly I'd cut the tubes to length, so I had little wriggle room there. One solution I hit upon was to flip the stays 180 degrees, plenty of clearance, but they stuck out a mile.

Looking through my workshop, I then spotted the last piece of bamboo that was in the kit. It's a small diameter tube to make the chainstay and brake bridges from. Taking a short section I discovered that it fitted beautifully into the existing tube.

So a bit of carving later and we had a new sleeve that was able to push out the seat stay by just the right amount from the seat tube, as well as bring a lot of strength into the joint.

I glued the insert into the tube and then made up some wood filler from wood glue and bamboo sawdust that I'd been saving up. I used the filler to smooth out the repair and provide a flat surface for the hemp and resin to bond to later. It doesn't look too pretty, but it doesn't need too and it is smooth.

I then proceeded to do the other seat stay and now were pretty much done with rectifying my earlier mistake. There's enough clearance there now and the tops of the stays bond nicely to the seat tube.

So I've also been messing around creating the Chain stay bridge and dry fitting that.

Not much more work to go now until I can think about tacking the whole rear triangle together, followed not long after by the hemp lugs. Maybe the main construction will be finished by Christmas? Still lots to do after that though.

 

[Smokin Joe]

I'm as nervous for you as I would be if I was building it myself!

Fantastic project.

 

[buzzy-beans]

Honestly, I think the quality of your workmanship @chriswoody is the dogs danglies, most especially the wood filler concoction you came up with.
In truth I am half hoping you will never finish this amazing project as I am getting so much enjoyment from reading every single update posting!

 

[raleighnut]

Just spotted this, might be of vague interest:
https://www.reddit.com/r/bustedcarbon/comments/5wsnpy/my_bamboo_and_carbon_bike_bambroke_today/
Fairly scruffy looking carbon taping, but seemingly rode fine until... that point.

I wonder if that guy had prepared the joints properly i.e. sanded the Bamboo to give the resin something to 'bite' onto?

 

[gaijintendo]

I wonder if that guy had prepared the joints properly i.e. sanded the Bamboo to give the resin something to 'bite' onto?

It does look like they let their puppy chew on it a bit first...

 

[chriswoody]

Thanks for the kind words @buzzy-beans It's not as perfect as I would like, but I'm pleased with the way it's going so far.

I wonder if that guy had prepared the joints properly i.e. sanded the Bamboo to give the resin something to 'bite' onto?

It is a bit of a mess and I do hope I don't end up like that! There does seem to be a number of factors that could be at play here. In the comments he does mention getting the lay up of the Carbon wrong which won't have helped and I do wonder if he did scrape back the outer layer of Bamboo like you mention. Another interesting point is that the tubes have been heat treated which give it that dark brown colour. Whilst some manufacturers do this (Calfee for example) the Bamboo Bicycle Club warn against this practice and claim that research has shown that this potentially weakens the Bamboo.

It does look like they let their puppy chew on it a bit first...

It does look a mess doesn't it? I'm a little puzzled by the end of the tube and what that mess is, maybe he's also used fiberglass as a base layer?

 

[raleighnut]

Thanks for the kind words @buzzy-beans It's not as perfect as I would like, but I'm pleased with the way it's going so far.



It is a bit of a mess and I do hope I don't end up like that! There does seem to be a number of factors that could be at play here. In the comments he does mention getting the lay up of the Carbon wrong which won't have helped and I do wonder if he did scrape back the outer layer of Bamboo like you mention. Another interesting point is that the tubes have been heat treated which give it that dark brown colour. Whilst some manufacturers do this (Calfee for example) the Bamboo Bicycle Club warn against this practice and claim that research has shown that this potentially weakens the Bamboo.



It does look a mess doesn't it? I'm a little puzzled by the end of the tube and what that mess is, maybe he's also used fiberglass as a base layer?

Thinking a bit further about this maybe he just 'layed' the CF on instead of wrapping it tightly around the joints to compress them, what does your kit say about tension. BTW I know your kit uses Hemp/Hessian but to my thinking that is a superior material to carbon fibre in this application especially when encased it a resin.

 

[chriswoody]

Could well be, the instructions in my kit are quite specific about the need for compression. After the Hemp/Resin is laid down, you need to wrap miles of electrical tape around the joints to compress them. I agree with you, for home made bikes, Hemp/Resin is a really straightforward and strong solution. I'm reassured by Kate Rawles amongst others, who are currently undertaking major tours on these bikes and having no issues.

The process for creating the lugs can be seen in this short video:

 

[User32269]

Thanks for the best thread ever! Can't wait to see more!

 

[xzenonuk]

looks awesome, would love to see the finished bike

 

[chriswoody]

looks awesome, would love to see the finished bike

At the rate I'm going it's going to be a little while I'm afraid, but stick around and I will finish it someday.

So this last week has seen me working on this tiny piece of Bamboo, (Apologies for the poor out of focus photo, it was a little hard to focus on it!)

Not only is it tiny and a pain to work with, but it has quite a complex shape. It's the brake bridge that the rear brake mounts to. It sits high up between the Seat stays, so the ends are not parallel. To add to the fun it also has to sit forward in the Seat stays so that the brake calliper will mount properly.

After a lot of whittling and sanding and measuring I had it sat in the right place and fitting like a glove. So I need to drill a hole through it now for the Brake Calliper mounting bolt, that should be fun!

After this, the main construction is finished and it's just a matter of binding it all together once and for all.

 

[QFour]

At the rate I'm going it's going to be a little while I'm afraid, but stick around and I will finish it someday

Don't know whats keeping you their Website says you can go on a course and build one in a weekend ..