Mild steel and stick welded frames
 

Hi all,

I have been thinking of building frames for quite a while now but neither have the money nor the tooling to do so. So before spending a significant amount of time saving up for the tools, i though i might al well start gaining experience.

My plan is to start with what i have and what is easily accessible to me. I already have a basic workshop with a stick welder, angle grinders, bench press and bandsaw. Combining these tools with standard metric mild steel from a local supplier could allow me to start manufacturing basic (heavy) bike frames.

The pros that I can see:

• Inexpensive way to get bike frame building experience
• Easily accessible materials
• Can cheaply experiment with different geometries/styles of bike frames

And now to my questions:

1. How realistic is building a bike with minimal tools and a lot of time?
2. How compatible is basic bike components to standard metric mild steel tubing?
3. Will it be more viable to buy cheap secondhand bikes to use their components and material?
4. Do you have any advise on getting started?

Thanks in advance

I have built a few frames and use oxy/propane for brazing. I think stick welding is going to burn through the tubes!
The other frame builders will be weighing in shortly.

One issue most of us don't think about until after a frame is built is making parts fit on the frame. Cranks and wheels being the biggest problems. If using standard steel, there are also issues with getting a headset to fit. For me, bike specific tubing isn't that much more expensive than standard steel. But I don't live in an industrial area.

As far as tools go, you really only need files, a hacksaw, and a vise. That's how I build frames.

I don't think stick welding will work, but I am not at all experienced with it.

The Op certainly could make a frame from common steel stock and stick welding. And the amount that will be learned will be vast. However the resulting frame won't likely be a nice riding lightweight and efficient pedaling bike, even if you get around what Eric mentions (which is a very good point BTW) about assembling with current available parts. (And this issue is one that some have commented on in the past. Some will say that Shimano and SRAM are the true bike designers and control what can be done by the frame builder, yet still keeping their customers happy and maybe make a few $ too.)

At one time most frame tubing suppliers, in the US, offered a "kit" of tubes and fittings that work together and a beginner could build with, without the issues of compatibility between the various bits and the goal of a quite rideable bike that frame wise compares well to better production frames.

I suggest the OP begin with playing with scrap bits and see how their skills create results. Then rethink the plans for a real frame with this gained knowledge. I note there's no location offered by the OP. If they were near by me (and a few others here I suspect) they could spend an afternoon/evening in my shop and ask away) Andy

The time depends on you. I think for most of us here a frame takes from a few weeks to 6+months due to other activities like real jobs. Minimal tooling is how most of us start. Some go out and spend a bunch on fixtures only to sell them when they realize they don't guarantee success. As Unterhausen says, files, hacksaw, blocks and something relatively flat is really.

I generally don't like cutting up old bikes to use the tubing. You have paint and chemicals inside the tubes that will create fumes and it's just a hassle. In the US and europe basic bike tubing is pretty cheap. If that's what you have, then go for it. Just protect yourself and know you aren't alone.

For tubing, the critical spots are where headsets, BB and seatpost fit. those are fairly tight tolerance fits.

All of that sounds negative. There are folks in India and what appears to be Africa who are doing exactly this. Yes, everyone laughs at them and says it won't work but they are actually doing it, so who is the fool?

I have done very little stick welding but I think the challenge will be distortion and blowing through thin walled tubing usually used for bicycles. If you're using thicker walled tubes, then that's probably better.

Not a framebuilder, but having had the experience of fitting parts to ill-prepared metal frames for so many years - I don't think you'll get buildable frames out of this method.

I would be more inclined to buy some enormous and cheap old hi-ten steel frames and either dissemble the lugs with torch or just cut and grind everything smooth for fillet brazing. Oxy acetylene and brass filler should be reasonably cheap.

You will likely burn through some tubes and warp others, but you'll be working with bike dimensioned lugs and at least have a shot of making a working bike. Hi-ten is not super thick, but is thicker than chromoly, so that will help. I realize there are lots of flaws with that suggestion, but I feel like you might learn more about bike construction.


Otherwise, use that stick welder to make other things besides bikes until you are very good, then jump back into bikes and TIG.

Will your budget stretch to a bottle of argon and a TIG torch? You can convert a stick welder to do scratch-start TIG. If you had that you would be off to the races. You don't really need any other tools. I basically use an angle grinder with cutoff wheels and flap disks (OK I'm a pleb but it works) plus the TIG and that's it. You can make a few simple jigs and fixtures with what you have.

If you can weld round mild steel tubing (presumably about 1.6mm thick) with your stick welder (probably want 6013 rods) and do a decent job then you can indeed build a basic frame that way. Scavenge the head-tube and BB shell from a scrap frame. They are quite thick metal so this is reasonable to do. Start by making some test joints and test them to destruction (won't tell you anything about fatigue but is a start).

Quality bicycle tubing is about half that thickness and not feasible to weld except with TIG.

Another type of fun project that people often do with stick or MIG is making things like cargo bikes, which are based on modifying an existing frame. Maybe a good place to start. I highly recommend this YouTuber below called Albert Nario. I think he's in the Philippines. He has awesome skills with very basic tools and stick welds everything.

https://www.youtube.com/channel/UChv...QaWdHJKtVet-9Q

Apparently people are building bikes out of rebar all the time. At some point it won't be novel anymore, but we haven't reached that point
https://makezine.com/article/home/fu...r-bike-frames/

Thank you for all the feedback and advise.

It seems that the first thing i will need is a TIG welder (might be a option to look for a second hand one for now).
Unfortunately I'm located in a isolated town in South Africa with no real option to order and get specialized steel delivered. That will have to happen with a multi day round trip. For now I'll start experimenting with standard steel tubing and focus on geometry and adjustable jigs for frame building.