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  1. #1
    30 Century Man bike sloth's Avatar
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    Junk frame - replace bent tubes with wood?

    I'll be up front and say that I have no frame building experience. I'm very mechanical, work on a lot of bicycles and cars, and have made some rather nice trebuchets and ballistas in my time, but have never made a bike frame.

    Now, I've been given a steel lugged frame with terminal damage on pretty much every tube. I only took it because the lugs/headtube/BB/dropouts/etc. are fine, it's the main tubes and stays that are junk.

    Could I unbraze the junk tubes from the lugs and replace them with some nice hardwood dowels? I'd imagine some nice Hickory or Iron Wood would be plenty strong. I'd probably make the chain and seat stays from a board of the same wood (thicker than the original tube diameter), cutting them into a wishbone shape. The seat tube would have to be replaced, too, so I guess I'd just make the new dowel go straight through the lug and act as the seat post.

    I've been checking out all the bamboo stuff going on and I really like it, I just really want a hardwood bike. I'm also familiar with Renovo bikes, although those are just a bit different than what I'm thinking of This is a purely experimental idea, so all input will be taken into account.

    My main questions:

    - Will it work?
    - Will it be safe?
    - Have you ever seen anyone do this before?
    - What kind of wood would you recommend?
    - What would be the best way to bond the wood to the steel lugs?

  2. #2
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    Will it work? Maybe.

    Will it be safe? I don't think so. But I might be wrong!

    What kind of wood would I recommend? Hickory, from my brief time mucking about with R/C airplanes.

    Best way to bond the wood? I've seen epoxy used to assemble aluminum frames, so....

  3. #3
    30 Century Man bike sloth's Avatar
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    The more I think about it the more it seems like a waste of time (not to mention potentially dangerous). If I'm going to make a wooden frame I might as well drop the steel lugs and make something out of some strong planks or plywood. And if I'm going to go and make a frame from scratch I might as well make that recumbent I've been wanting for years. Now the question is bike or trike?

    Still open to input on homemade hardwood bike frames...

  4. #4
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    General rule for joints is that you need an overlap of 1.5 x diameter. Lugs get away with being more skeletonized because of the high holding power of brazing in shear. That would not work with wood. It would probably be possible to make a bike that looked as though it was held together by lugs and was all wood, with hidden structure. But the real deal of epoxying the parts together would not work, it wouldn't even work with metals.

    If you use hickory, pay particular attention to getting wood with extreme high quality and minimal grain run-out. When I started out in moutain climbing in the 70, they ice tools we had for vertical waterfall climbing mostly had hickory handles at the time, or laminated bamboo.

  5. #5
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    What if you took a bike frame using large diameter tubing and chopped it up to make heavy-duty lugs?

  6. #6
    weirdo
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    Ooohhh! you guys got my imagination rolling now! When I read the first part of the original post, I thought of Renovo, too. I was gonna say go for it and just use it for bikepath stuff, but I think Peterpan is right about the short and skeletonized lugs. Spastic, there`s no need to chop up a frame, it would be simpler to just fab the lugs from virgin tubing than try to cut it from an already brazed frame. Lugged wood- maybe dark wood like cherry with brass or stainless lugs? It just occrus to me that a softride might be the easiest way to get around the seatpost problems, though I don`t care much for how softrides look.

  7. #7
    Senior Member squirtdad's Avatar
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    If you want the wood look, without the structural concerns, a person could look at veneer. It would be a reall challange to get the veneer around the smaller stays.....but maybe with vacuum bagging?

    just another idea for creative juices........
    '82 Nishiski commuter/utility
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    looking for: De Rosa 58cm ELOS frame and fork internal cable routing

  8. #8
    Senior Member icelemmings's Avatar
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    I am in your same position—mechanical, a good amount of experience working on bicycles/building things—that said, no frame building experience.

    I've wanted to make a wooden dowel frame bike with steel lugs for some time now. I still haven't cracked it—any set-up I sketch, ultimately, seems like it would be unsafe.

  9. #9
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    Quote Originally Posted by Spasticteapot View Post
    What if you took a bike frame using large diameter tubing and chopped it up to make heavy-duty lugs?
    Ding-ding-ding, we have a winner! that is a great idea! he could even use his original bike just dont take it apart at the lugs but further down the tubes and epoxy it together, his seat tube idea is fine, he would need to cut off an old seat post and invert it at the top of the new wooden seat mast, hickory would be fine but some of the exotics have promise as well, the strength of the iron wood would be nearly unmatchable, but purple heart or even osage orange would prove just as sturdy, I hope he tries it. you know, a thru -rivet like in a shovel handle might not be a bad idea at the main junctions in conjunction with the epoxy. I think it will be a great conversation piece as well as a daily rider.
    keep us posted !

  10. #10
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    The one thing with that approach is that the inside diameter of bike tubes is not garanteed to be a fit to any other size of tubing you would want to use. If you have 1.25 tubes and want them to accept 1.125 tubes they need to have 1/16" walls which a really cheap bike might actually have, but then you have the problem of a precision fit right up to the junction. At the end of the day it is cheaper and better to just buy some inexpensive lugs.

  11. #11
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    Quote Originally Posted by Peterpan1 View Post
    The one thing with that approach is that the inside diameter of bike tubes is not garanteed to be a fit to any other size of tubing you would want to use. If you have 1.25 tubes and want them to accept 1.125 tubes they need to have 1/16" walls which a really cheap bike might actually have, but then you have the problem of a precision fit right up to the junction. At the end of the day it is cheaper and better to just buy some inexpensive lugs.
    He wants to replace the tubes with wooden dowels not new tubes, so using new lugs is out because it is not a long enough sleeve, but salvaging a bike with bunk tubes is talior made for a project like this, not a project I have time for but Spasticteapot got me thinking anyway, that was a really good soulution for the OP to consider

  12. #12
    Senior Member w98seeng's Avatar
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