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  1. #1
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    Shoud a 36er pop my cherry?

    I'm a mechanical engineer who loves to fiddle in the garage. I've been contemplating building my own frame. It would be on the sketch, without pricey jigs, and I'm undecided if I would use a tig welder or fillet braze. Definitely steel. Would you talk me out of making a 36er for my first frame? I can figure out what geometry I want and I think there is enough knowledge here to steer me in the right direction. Any reason a 36er would be more difficult than a 29er? FYI, I'm 6'4" so geometry shouldn't be too stupid.

    Edit: I'd probalby buy a fork from Walt if you were wondering.

  2. #2
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    It'll probably be trickier that something more run of the mill. But if you want to build a 36er, I think you should build a 36er.

  3. #3
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    Um....this is what I did after buying a custom bike from Retrotec and visiting Curtis's shop/house the bug bit hard and seeing a 36er (Keeners) and finally getting touch one at Outdoor Demo. I say touch because they wouldn't let us ride it (Blacksheep with a Gates belt drive) right then I knew it would be a 36er for my first bike!

    Using straight gauge tubing makes it easier to build a large wheeled bike because the butted tubing offered isn't quite long enough to get around ,over or by without doing some compromising. You'll need to have or access to some tubing benders if you go this route though.

    As far as a jig a home made 80/20 one wasn't that hard to build
    and it only cost about $400.00. To set up the jig I cheated just a little
    I used a 29er frame that I liked and just stretched the measurements.
    PAYASO 36er.....Live the Circus

  4. #4
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    The thing with a 36er is off the shelf forks don't exist. And frame #1 isn't really the place to R&D a loooooong first built fork. I don't know your fab experience, but essentially you will need to build a fork..... Or give Walt some $, like I did/am doing.
    Slowly slipping to retrogrouchyness

  5. #5
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    Yeah if I build a 36er, Walt will definitley be building a fork for me

  6. #6
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    Shoud a 36er pop my cherry?

    Wouldn't a Krampus fork work?

  7. #7
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    The Krampus is a stupid long fork (corrected for a 120mm 29er), but not quite stupid long enough.
    Slowly slipping to retrogrouchyness

  8. #8
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    Shoud a 36er pop my cherry?

    What is the outer diameter of a 36er wheel?

  9. #9
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    I used a jamis suspension corrected 29er fork on my first 36er but having the wrong rake made it feel like a steering damper, this wheel size needs almost double the rake
    And Walt suggested 80mm when he made me a fork it works very well.

    As far as the true wheel/tire height it's between 35 3/4"-35 7/8" depending on air pressure.
    PAYASO 36er.....Live the Circus

  10. #10
    Squelch the weasel.
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    My first build was a road bike with 20" wheels. It was harder because the standard answers you'll find have to be adjusted for doing anything weird. Ultimately, the bike really sucked and I'm very glad I did it. I learned a lot. I still rode the thing for over a year, even though the geometry was insane and the shifting was bad because of the super-short chainstays.

  11. #11
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    Good feedback, thanks guys. I'm not proficient at either Tig or Brazing and would be essentially starting from scratch either way. Which one will be easier to learn and make the strongest frame provided my skills won't be that great? I'm over 300 lbs so it'd be straight gauge tubing which I think would make the welding/brazing easier due to thicker material?

  12. #12
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    Over the years I've seen a number of threads like this, and usually just move on.

    If you are serious about building frames, or anything else, my advice would be that you first enroll in a good welding class, which hopefully will be taught by a master welder who will provide you with an understanding of welding basics that include theory, metallurgy, heat treating, and both non-destructive and destructive testing.

    Once you have done that, and you have passed the all of the classroom tests, and you are capable of making welds that pass testing, you will be qualified to start welding bicycle frames. Until then, don't weld anything that will see more stress than the handle on a lawn mower.

    One other thing. In addition to being the answer to the question that nobody asked, 36-inch wheels are stupid. The bike you are proposing sounds like it will be so bulky and heavy it will be slower and heavier than a 300-dollar Craigslist Rockhopper.

    It may not sound like it, but I'm trying to help you.

  13. #13
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    From one noob to another, I'd build a simple bike first. And, before any bike tubes are cut, I would practice on a bunch of scrap pieces first. I have a local bike coop near me and I bought a handful of old, beat up, unusable frames, hacked the tubes up, and practiced my brazing. When you think you have practiced enough to build a bike, practice more. I wouldn't invest time or money into a jig yet. I'm still using my DIY jig that is Shiggy's version of Dr. Welby's design. It's cheap, dirty, and does the trick.

  14. #14
    AZ
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    Quote Originally Posted by Sasquatch1413 View Post
    Good feedback, thanks guys. I'm not proficient at either Tig or Brazing and would be essentially starting from scratch either way. Which one will be easier to learn and make the strongest frame provided my skills won't be that great? I'm over 300 lbs so it'd be straight gauge tubing which I think would make the welding/brazing easier due to thicker material?


    Spend some time learning the skill and then revisit this. Who knows, you may turn out to be some kind of Savant but I would expect that you'll spend more than a few days learning to TIG or braze proficiently.

  15. #15
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    Yes, right now I'm not too serious about building a frame but the interest is growing. And for some odd reason, I can't get the thought of a 36er out of my mind. I agree with Roadster, 36er is not the best machine for really anything other than being cool as **** and that is obviously highly subjective.

    I need to do some research into what method I'd prefer (tig or braze). From there I agree it will be practice practice. I've also been wanting to make some bike racks so that will be good brazing practice.

  16. #16
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    Quote Originally Posted by Roadsters View Post

    One other thing. In addition to being the answer to the question that nobody asked, 36-inch wheels are stupid. The bike you are proposing sounds like it will be so bulky and heavy it will be slower and heavier than a 300-dollar Craigslist Rockhopper.
    .

    And how many 36er's have you ridden?


    I agree with getting some formal training if you don't already have it
    And practice is key.
    PAYASO 36er.....Live the Circus

  17. #17
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    Quote Originally Posted by Sasquatch1413 View Post
    I need to do some research into what method I'd prefer (tig or braze).
    For most people I think this decision is mostly a question of access and economics. If you have access to both, then it's probably a question of whichever you are most comfortable with. Generally brazing is more beginner-friendly, but if you can try both, see what works for you.

  18. #18
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    As has been stated earlier, do something conventional for your first frame. Build weird stuff starting with frame 4.

    OT, but any other engineers unimpressed by an engineering degree as a reason to think that someone might be capable of building a frame? I have a Ph.D. in Mechanical Engineering, and other than a class in composite analysis, nothing I learned in school or worked on in my career prepared me to build frames.

    OTOH, I would love to teach a framebuilding class to engineering students.

  19. #19
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    I'll quickly chime in here:

    -Build something you want to build, but not something you'll be heartbroken about if something (or many things) aren't quite perfect. It's your first frame, you'll screw up at least a few things.

    -36ers present a few extra challenges (chainstay length, getting the seat tube out of the way of the tire, sourcing/building a fork, etc) but nothing terrible. That said, it will definitely be somewhat more difficult than a more conventional frame.

    -36ers make great town bikes/conversation pieces if there's enough wrong with frame #1 that you don't want to use the bike for "serious" riding. Personally, I'm not sure any mountain biking is "serious" unless you're delivering medicine to remote villages or something but that's another topic.

    -Parts are expensive as all get out (basically wheels - even building them yourself and using dirt cheap hubs you'll spend $600+) so if money is a concern another wheel size might be better.

    Honestly, there is nothing very logical about building yourself a bicycle frame when there are so many great options available out there for so little money. So this is really about your own satisfaction and enjoyment, and if what you want is a 36er, then by all means build it! And post up your progress as you go!

    -Walt
    Waltworks Custom Bicycles
    Park City, UT USA
    www.waltworks.com
    waltworks.blogspot.com

  20. #20
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    Quote Originally Posted by unterhausen View Post
    OT, but any other engineers unimpressed by an engineering degreUe as a reason to think that someone might be capable of building a frame?
    I'm not impressed by much about the younger, slower cousin of physics.

    *for those of you who take teh internetz too seriously, this is a joke, and a referential one at that.

  21. #21
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    Quote Originally Posted by unterhausen View Post
    OT, but any other engineers unimpressed by an engineering degree as a reason to think that someone might be capable of building a frame? I have a Ph.D. in Mechanical Engineering, and other than a class in composite analysis, nothing I learned in school or worked on in my career prepared me to build frames.
    Hmm, I was ME and that's where I learned to weld and run a mill and lathe. But there were some other MEs in my shop class that I wouldn't trust to saw wood with a handsaw.

    We also looked at bikes in our Vehicle Dynamics class and the ME department had a rear-steering bike so everyone understood about dynamic instability. Though that might have something to do with being at UC Davis.

  22. #22
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    Quote Originally Posted by unterhausen View Post
    As has been stated earlier, do something conventional for your first frame. Build weird stuff starting with frame 4.

    OT, but any other engineers unimpressed by an engineering degree as a reason to think that someone might be capable of building a frame? I have a Ph.D. in Mechanical Engineering, and other than a class in composite analysis, nothing I learned in school or worked on in my career prepared me to build frames.

    OTOH, I would love to teach a framebuilding class to engineering students.
    Actual fabrication and construction skills...no, but a mathematical mind to understand geometries, trail, materials....yes. Sticking tubes together in a structurally sound manner will be the hard part. I'm confident that I can get geometry figured out, work out tube miters, and rig up some sort of jig on the cheap.

    I've already got "normal" bikes that I love to ride. If and when I build a frame, it will be a 36er monstrosity. Much thanks for the feedback guys, I'm impressed that I got over 50% positive responses, is that some sort of record?

  23. #23
    WIGGLER
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    So are you popping your.......a....your.....cherry?
    PAYASO 36er.....Live the Circus

  24. #24
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    I am bulding a 36er, my bro got into frame building before i did though so he is building the frame and fork for me. Im in the process of building the front wheel and thats enough of a pita. Not building up as round as id like.

    I do have one question though todwil, what trail are you running with your fork on your 36er?

  25. #25
    WIGGLER
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    The rake of the fork is 80mm and I did a quick measurement and it looks like 89mm-ish of trail
    PAYASO 36er.....Live the Circus

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