Instructables
Picture of Iron Tandem - Bicycle/Recycle Project
This instructable explains how to save two old bicycles from the grave to create one immortal tandem bicycle.  

I had always fancied building something for fun and actually dedicating a bit of time to a project rather than just the odd quick fix here and there.  With a charity bike ride looming a couple of months away it seemed like a great idea to try to build a tandem and enter it just for fun.  A few friends and I had entered the event the previous year dressed as glam rockers and it got a good response so we decided to repeat it this year.  (Hence why this tandem has a bit of a Gothic look to it!)

I had never ridden a tandem before and didn't really know what I was aiming for so I looked online at some different frame designs to gain some inspiration.  I decided that I didn't want my bike to look like two bikes - I wanted it to look like a genuine tandem frame.  I also learned that having a decent spacing between the driver and passenger was essential to ensure that the passenger could actually see some scenery and not feel too cramped on the back.  Throughout this instructable I refer to the driver as the 'captain' and the passenger as the 'admiral' because this is proper tandem lingo dontcha know!

This bike cost very little to build as most of the existing components were cleaned up and reused.  The only parts bought new were bearings, chains and cables.  The only really specialist tools I used were a bicycle chain tool (cheap) and a MIG welder (err, not so cheap)

Tools you will need:
- A pair of grips
- A pair of pliers and cutters
- Allen keys and spanners (various sizes depending on your donor bikes)
- Hammer/Mallet (for persuading stubborn bike parts to come off)
- Screwdrivers
- Sandpaper
- G-clamps or large magnets (for holding the frames together when welding)
- Angle grinder (with cutting disc and grinding disc if possible)
- Metal hole cutters (you could use a hacksaw and then file the tubing to shape but this takes a LOT of time)
- A pillar drill (a pillar drill is ideal in order to cut the angles more accurately but a similar result can be achieved using a hand drill and a jig)
- Bicycle chain tool
- A MIG welder - or gas/TIG if you have one available!
- Some wood to make up a frame jig prior to welding
- Spray paint (primer and colour)

Other things you will need:
- Some old bikes! (Free)
- Piece of mild steel tube (from scrap metal yard £10 / $17)
- Paint (£25 / $40)
- Bearings and cables (£10 / $17)
- Chains (£7 / $11 each)



 
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Mr.Sanchez9 months ago
I love Metal too.
100_3916.JPG
Wroger-Wroger9 months ago
Nice effort.

I am shit frightened of bikes coming apart underneath me, especially at speed, down a big hill, hitting some rough road while going fast, with a truck coming up behind me.

Just horrible - and almost entirely avoidable.


There are two sorts of frame failures.... the slowly developing ones - that give plenty of warning when things get a bit loose and sloppy... over time, or where they go "wobble wobble" and then the frame breaks in two.

I think this would be a very lovely bike for the casual riding - like 20Kmh around town and country side rides.

I'd be a little bit wary of going down big hills fast, on pot holed roads, with trucks up my arse.

For a serious bike - I'd be getting a proper engineering books on welding, the engineering of tandem bicycle frames and the properties and treatments of assorted frame building steels.

It's like the subtlties of bolts. The classic 8mm bolt - then the classic high tensile grade 8 - 8mm bolt... and then the aircraft certified high tensile bolt.

They do not use corner bolt / auto shop high tensile bolts in air craft.....

For good reason.



I'd also be doing a basic welding certificate - at least to be able to use all the equipment with reasonable competency.

Nice job on the butting up of the frame tubes.

stewkingjr9 months ago
If the grips don't slide on easily, lube with hairspray instead of soap or plain water. It dries quickly enough and won't slip once dry
rint9 months ago
iron maaaaaaaaaaiden
hagaar9 months ago
Nice project for a good cause! Well done.
manudel9 months ago
Where did you buy the bicycle parts? Could you suggest me a cheap bicycle-parts website?
Thanks and nice work!!
many_methods (author)  manudel9 months ago
Hi and thanks for your comment. I use Chain Reaction Cycles online. eBay is also good for used parts and parts for older bikes. Good luck!
Good job, and lovely pix, though some presented at odd angles. I enjoyed your instructable. Lots of good tips.
or the grips you should use dilute soap solution, dishwashing soap works just fine. Once it dries they're stuck on. I've used this method for years and years.

Also you can keep all the chains on one side if you tie the two cranks together with a fixed chain around the two smaller front chain rings.

See Brad's DIY tandem here at Atomic Zombie: http://www.atomiczombie.com/Tutorial%20-%20Simple%20MTB%20Tandem%20-%20Page%201.aspx
Kevanf19 months ago
I don't know if it would work but you could always try warming the handlebar grips with a hot air gun (or hair drier). It may just expand them enough for them to slip on easier. Another thing. Have you considered brazing the tubes together? Much less chance of distortion and a braze is certainly plenty strong enough. I had a fair few bikes with frames that were brazed in my teens.
kjlpdx9 months ago
at first glance I thought this was titled "Iran Tandem" :-) while you haven't had any problems, I'd question some of your very important welds, the penetration doesn't seem very good. when the welding bead looks like caulking there is little strength and it is just laying on top. nice job on this article.
icarus1249 months ago
Saw the logo on your bike pic and immediately started doing the intro to " The Trooper "..... good job and up the irons
Honus9 months ago
Nice! MIG is fine for thicker walled tubing- I've done it plenty of times and it works best on the less expensive bikes that use high tensile steel tubes. It's the more expensive bikes that use the thin walled chromoly with short butted sections on the tube ends and for those TIG is the way to go.