My first frame

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  • 12-05-2012
    Beatniqwood09
    7 Attachment(s)
    My first frame
    For my first frame im pretty much mimicking my current trek/gf marlin (with a small adjustment to the HA) I have no experience with metal work and will be doing all of this under the close eye of a buddy of mine who has built about 8 or so frames. It'll have a 70.3ish HA with a RS reba RLT 29er g2(51mm offest) 16.75 CS with a just a smidge left with 2.35's.

    Im using a Nova 29er tubeset, 35mm DT 969. Also got 700mm of thicker headtube since I thought the one from the set was kind of thin for my first build (and now i have head tubes for my next bikes:thumbsup:)

    I would comment on each photo but i dont know how to put text in between photos so i guess theyll all be as one, but here is my progress so far, please feel free to critique or give advice, id like to learn as much as possible.

    Commence photo dump
  • 12-05-2012
    febikes
    Looks like a great start!
  • 12-05-2012
    Walt
    More filler!
    Great start!

    Do some more practice joints. You've got waaay less filler there than I think you probably want (unless you're planning to add more once the DT is on) and you've got tons of high spots/low spots and probably plenty of voids you can't see. Braze a bunch of stuff together and make big, fat fillets until you can do it consistently without having half the filler run off away from the joint or onto the floor. Cut those practice joints in half and see how you did inside the fillet and tube as well.

    Once again, awesome start. But I think you should do a little more practice before doing the actual frame. Cruise over to Garro's site (coconinocycles.blogspot.com) and check out some of his joints - that's what you're aiming for.

    -Walt
  • 12-05-2012
    Beatniqwood09
    Quote:

    Originally Posted by Walt View Post
    Great start!

    Do some more practice joints. You've got waaay less filler there than I think you probably want (unless you're planning to add more once the DT is on) and you've got tons of high spots/low spots and probably plenty of voids you can't see. Braze a bunch of stuff together and make big, fat fillets until you can do it consistently without having half the filler run off away from the joint or onto the floor. Cut those practice joints in half and see how you did inside the fillet and tube as well.

    Once again, awesome start. But I think you should do a little more practice before doing the actual frame. Cruise over to Garro's site (coconinocycles.blogspot.com) and check out some of his joints - that's what you're aiming for.

    -Walt


    I did do a few practice rounds before I started, but i've already cut into these tubes so theres not much turnin back from here. That was only supposed to be the 'tinning' but i got a little carried away, when im ready to put the whole front triangle together it's definatly going to get a serious fillet.
    Thanks
  • 12-05-2012
    adarn
    Nice. Also, what kind of flux is that?

    It looks a lot like the silver flux that I tried using when I started. If it is, at least go get some higher temp stuff. It will make a huge difference.

    Good luck!
  • 12-06-2012
    jay_ntwr
    Quote:

    Originally Posted by Beatniqwood09 View Post
    I did do a few practice rounds before I started, but i've already cut into these tubes so theres not much turnin back from here. That was only supposed to be the 'tinning' but i got a little carried away, when im ready to put the whole front triangle together it's definatly going to get a serious fillet.
    Thanks

    I'd take that joint out and finish it before moving on. You'll be able to cut more material off the DT to match the fillet and have a good joint to start with. I'm a TIG guy though so YMMV w/ brazing but there's no way I'd finish the DT/BB/ST joint with that inside the DT.

    Other than that, it's looking like a good start on #1. I'd also echo more practice, cut tubes aren't going to change size now. Just get more proficient and then go to the tubes again. One of the biggest things I learned is that getting in a hurry is the quickest way to ruin a frame. You'll be happier in the long run the slower you go on the first ones.
  • 12-06-2012
    zebrahum
    Good start, I'm interested to see more of the process. I've built a lugged frame and I'd really like to try my hand at fillet brazing soon.

    In order to add pictures in line with commentary use the little yellow icon with a mountain and a moon "Insert Image" instead of attaching files. You will need to upload the photos to an online storage system (I use Photobucket) but you can add text between the IMG tags.
  • 12-06-2012
    Beatniqwood09
    Quote:

    Originally Posted by jay_ntwr View Post
    I'd take that joint out and finish it before moving on. You'll be able to cut more material off the DT to match the fillet and have a good joint to start with. I'm a TIG guy though so YMMV w/ brazing but there's no way I'd finish the DT/BB/ST joint with that inside the DT.

    Other than that, it's looking like a good start on #1. I'd also echo more practice, cut tubes aren't going to change size now. Just get more proficient and then go to the tubes again. One of the biggest things I learned is that getting in a hurry is the quickest way to ruin a frame. You'll be happier in the long run the slower you go on the first ones.


    Are you saying to put a big fillet around the ST/BB and make it smooth, and then adjust the miter on the downtube to make up for the extra filler?
  • 12-06-2012
    RCP FAB
    I can't tell from the image, but it seems that you drew the fork rake incorrectly on your print. Rake is measured 90* to the fork length, not parallel to the axle line. If you did this, and build the frame to those numbers, when built everything will be about a degree steeper and the bb a little bit lower than you planned.
  • 12-06-2012
    jay_ntwr
    Quote:

    Originally Posted by Beatniqwood09 View Post
    Are you saying to put a big fillet around the ST/BB and make it smooth, and then adjust the miter on the downtube to make up for the extra filler?

    Yes. That would be my preference. Again, I'm not a fillet guy, but that's how I would do it. I suppose having a fillet guy chime in here to confirm would be valuable.
  • 12-06-2012
    adarn
    I'm a fillet guy. I usually tin the joint/internal braze. So a really small fillet, then fit the DT and then put a big fillet down when I braze in the DT and CS's.

    I am pretty sure that this is the way most fillet guys are doing it. The joint will be stronger if you are mitering steel to steel rather than steel to brass.
  • 12-06-2012
    Beatniqwood09
    Quote:

    Originally Posted by RCP FAB View Post
    I can't tell from the image, but it seems that you drew the fork rake incorrectly on your print. Rake is measured 90* to the fork length, not parallel to the axle line. If you did this, and build the frame to those numbers, when built everything will be about a degree steeper and the bb a little bit lower than you planned.

    Oh wow. I cant really say right now because my buddy who's teaching me did the majority of the math on this and the drawing is at his house but I'll definitely confirm this with him before I do anything else.

    Thanks
  • 12-06-2012
    Beatniqwood09
    Quote:

    Originally Posted by adarn View Post
    I'm a fillet guy. I usually tin the joint/internal braze. So a really small fillet, then fit the DT and then put a big fillet down when I braze in the DT and CS's.

    I am pretty sure that this is the way most fillet guys are doing it. The joint will be stronger if you are mitering steel to steel rather than steel to brass.

    That's what i thought, so should I file down the tin near the tips of the DT so as to get as much steel on steel as possible?
  • 12-06-2012
    adarn
    It looks like you're probably ok. Some cleaning up definitely wouldn't hurt. I usually soak it and take off the old flux and do some minor clean up if needed. Your fillet looks like you need to keep your torch moving more and work more brass into the joint, but it's hard to tell from that pic.

    Take your time, really take time to think things through, take more time and it should turn out good.
  • 12-06-2012
    whydomylegshurt?
    I would suggest using more flux. Personally I put a thin coating of flux on any part of the tube that is going to get hot. That means a few inches away from the joint in all directions. I keep the paste flux very thin and use a powder flux on the brass rod. I fing this keeps clean up easy, protects the tube and places just the right amount of flux at the joint. If you don't have good powder flux just add a bit more paste around the joint.
  • 12-06-2012
    Beatniqwood09
    Quote:

    Originally Posted by RCP FAB View Post
    I can't tell from the image, but it seems that you drew the fork rake incorrectly on your print. Rake is measured 90* to the fork length, not parallel to the axle line. If you did this, and build the frame to those numbers, when built everything will be about a degree steeper and the bb a little bit lower than you planned.

    Figured it out. The rake (which is the same as offset correct?) was measured at the headset and drawn down from there
  • 12-06-2012
    Beatniqwood09
    Turns out yall were right. Did some check measuring before i got started today and found my BB had moved a few mm out of line. So we got it reset and went to cold set the seat tube so it fit back in the jig and the fillet cracked on the acute side. :rolleyes: My buddy seemed fairly confident that we could re-braze the cracked side and still form a solid joint.

    I think my problem lies with temperature control and knowing that the thicker tube will require more heat, as opposed to heat straight into the joint
  • 12-06-2012
    RCP FAB
    Quote:

    Originally Posted by Beatniqwood09 View Post
    Figured it out. The rake (which is the same as offset correct?) was measured at the headset and drawn down from there

    :thumbsup:
  • 12-06-2012
    TrailMaker
    Hey;

    I've had a ton of variously related fabrication experience behind me before building my first frame 6 months ago. The bicycle specific concepts - components & geo - were the only things really new to me. To be starting off at total ground zero with no experience in either is a mega leap!

    (applause!)
  • 12-08-2012
    Beatniqwood09
    1 Attachment(s)
    Still needs some miter work but slowly coming together :D
  • 12-08-2012
    dru
    I've only built one myself, but I remember quite well all the worrying and not knowing quite what I was doing. The frame is into its 3rd season and I'm riding it tomorrow morning.

    Yours looks like its coming along quite nicely. You'll be pretty stoked when you ride it.

    I agree completely with Walt about more filler. (and more flux from 'sore legs') When I did mine there were a few joints that needed three separate hits before I had enough filler. All that reheating to brazing temps can't be good for the metal.

    Drew
  • 12-09-2012
    TrailMaker
    Hey;

    Is it an optical illusion, or do the TT & DT seem to nest very close together, relative to the length of the HT?
  • 12-09-2012
    Beatniqwood09
    Quote:

    Originally Posted by TrailMaker View Post
    Hey;

    Is it an optical illusion, or do the TT & DT seem to nest very close together, relative to the length of the HT?

    They were designed that way and the HT was left long so a had a little wiggle room for error and brazing. It will most likely be lopped off after the brazing is done. Are there any potential issues having them that close?
  • 12-09-2012
    adarn
    Remember that if you're cutting HT off of the bottom, you are lowering your front end.
    And that looks fine to me. I've seen plenty of builders making frames with the head HT extending further beyond the TT and DT.
  • 12-09-2012
    Beatniqwood09
    Quote:

    Originally Posted by adarn View Post
    Remember that if you're cutting HT off of the bottom, you are lowering your front end.
    And that looks fine to me. I've seen plenty of builders making frames with the head HT extending further beyond the TT and DT.

    Thanks, the definitely makes sense. Just gotta decide whether i want to leave it and not run spacers and cut it down and put spacers. Any opinions?