Results 1 to 23 of 23
  1. #1
    mtbr member
    Reputation:
    Join Date
    Jul 2018
    Posts
    10

    Tubeset for Rowdy HT

    I am about to purchase my first set of tubes for my first build and just have a couple clarifying questions. The plan is to build a rowdy hardtail with 27.5+ and a 140mm fork by fillet brazing (I have been practicing and they are starting to look pretty good I think). I'm planning on basically copying the geometry of the Nukeproof Scout 290. My questions below are based on a general idea of what I want out of a bike, but having never built one, there are a bunch of things I don't know.

    I'm looking at this tubeset from Nova

    1) Is building a boost rearend any more difficult? Any other considerations?

    2) Which BB makes the most sense? I see 73mm threaded on a number of bikes, would that be wise for this purpose? I'm not a huge fan of PF BBs, but could do that if it makes more sense. I was thinking of this one

    3) On the tubeset above, I have a choice on the HeadTube and have no idea which one I should buy.

    4) Since I want to do Boost with a burly rear end, I'm looking at these dropouts <- is that what I want?

    5) What do I do about a rear disc brake mount? I have been searching around and am confused because most manufacturers seem to do different things.

    6) What about extra bracing? Ex/ Honzo has a piece between the ST and TT, or like this DJ bike has a flat piece on both sides near the head tube.

    7) Any other gotchas I haven't thought of? I have read a bunch, but most of the guides are about lugs and road bikes, which I would do first if I actually wanted a road bike.


    Thanks in advance for your help! I want to order these tubes and start figuring out the miters - thats the hardest part I have seen so far.

  2. #2
    pvd
    pvd is offline
    mtbr member
    Reputation: pvd's Avatar
    Join Date
    Jan 2006
    Posts
    3,289
    Learn and understand geometry. Don't copy.

  3. #3
    mtbr member
    Reputation: Feldybikes's Avatar
    Join Date
    Feb 2004
    Posts
    865
    I'm planning on basically copying the geometry of the Nukeproof Scout 290.
    I'm sorta with PVD on this one. OTOH, if the biggest/only hangup of you building your own frame is figuring out geometry, there's not necessarily anything wrong with copying an existing bike.

    I'm looking at this tubeset from Nova
    Too thin for a first frame. Especially with your intended application. You want .9/.6/.9 or 1/.7/1mm walls. Try vari-wall

    1) Is building a boost rearend any more difficult? Any other considerations?
    Boost usually makes everything easier. I guess you need to pay more attention to heel and crank/chainstay clearance. But these things are harder to mess up than tire or chainring clearance. (Though not impossible to mess up)

    2) Which BB makes the most sense?
    I can't see why you wouldn't do 73mm.

    3) On the tubeset above, I have a choice on the HeadTube and have no idea which one I should buy.
    At the risk of sounding like a d!ck, if you can't figure this one out, then you've got a lot more research to do. Hopefully the fact that I'm answering the rest of these questions speaks that my motives here are altruistic and not trolling.

    4) Since I want to do Boost with a burly rear end, I'm looking at these dropouts <- is that what I want?

    5) What do I do about a rear disc brake mount? I have been searching around and am confused because most manufacturers seem to do different things.
    Get some dropouts with a disc mount built in. Like from Paragon.

    6) What about extra bracing? Ex/ Honzo has a piece between the ST and TT, or like this DJ bike has a flat piece on both sides near the head tube.
    Don't have the seat tube stick up so high you need a brace. Also, if you don't know if you need gussets near the head tube or not, then you probably don't know how to build them in a way where they'll actually be helpful and not add additional HAZ and/or act as a can-opener.

  4. #4
    mbtr member
    Reputation: scottzg's Avatar
    Join Date
    Sep 2006
    Posts
    4,966
    I think you should copy a frame you know for your first frame. Proof of concept, see if it rides how you expected.

    Here is an old thread with some interesting discussion about gussets. I don't use them personally, but sleeves are game-on. (that seat tube requires a sleeve, and is designed for a 27.2 post)

    These
    are a good way to go for an early frame that you want to use a through axle. The sliding dropouts can save you if you screw up a miter and cut your stays too short/different lengths, and you don't need to weld on a disk tab. They're expensive and need to be silver brazed in, though. I think these are a good way to go for a first frame; although they're not a through axle design it doesn't matter much on a ht.


    I agree you should read more before you start putting things together. I like to have already figured out exactly why i'm choosing every tube/brazeon/etc, where the butts will be on my frame, and exactly what my process and such will be before i start putting together a grocery list. Then i'll ask someone to review me cuz i'm not infallible. This forum is probably the best one i know of for mtb framebuilding wisdom. There's some fantastic contributors here; high content:fluff ratio. It's hard to hold someone's hand with this, so a lot of the information ends up being kinda vague, unfortunately.

    Have you modeled your frame yet?


    The best thing you can do is find someone who you can chat with in person whose built some similar frames. If it goes well you'll build another one.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  5. #5
    Moderator Moderator
    Reputation: Walt's Avatar
    Join Date
    Jan 2004
    Posts
    7,107
    What are you using to miter the tubes? If you're a first timer and a big/aggressive rider, if you can figure out a way to miter some 1/.7/1 tubes from Vari-Wall, that's what I'd do.

    If you're filing, that's going to suck. Do the biggest diameter Nova 9/6/9 tubes you can get.

    Don't do gussets. You will probably only make things worse.

    Good luck!

    -Walt

  6. #6
    pvd
    pvd is offline
    mtbr member
    Reputation: pvd's Avatar
    Join Date
    Jan 2006
    Posts
    3,289

  7. #7
    mtbr member
    Reputation:
    Join Date
    Jul 2010
    Posts
    123
    I don't think copying geometry is such a bad idea for your first frame. The catch is make sure you're copying geometry that you'll actually like. Truly understanding the geo of mountain bikes is a long road, and it's pretty easy forget about an aspect or two when you're starting out.

    I would definitely use at least .9/.6/.9 tubes in those diameters. If you copy the Nukeproof, probably a 1/.7/1 downtube if you can, but like Walt said, if you're filing, that might suck.

    Others here have given you a lot of good info. A hint about the headtube is to just get a 44mm head tube. (further hint, that refers to the ID).

    If you decide to make the top tube/seatstay junction as low on the seattube as that nukeproof, be sure you know what you're doing when you make a brace. Certain seat tubes and top tubes won't work with that design because of their thin sections. It's pretty simple to just make that junction higher up towards the top of the ST.

    Sleeving seat tubes is it's own whole rigamarole. There is a straight seat tube from Vari-wall that fits a 31.6 dropper and can be used out of the box:https://shop.vari-wall.com/Steel-Tub...4518_c-425-01/
    Myth Cycles handbuilt bike frames
    Durango, CO
    http://www.mythcycles.com

  8. #8
    mtbr member
    Reputation:
    Join Date
    Jul 2018
    Posts
    10
    Thanks All!

    I see the vari-wall and some of the other components. For this first build. I was going to try to keep things as simple and inexpensive as possible because I am guessing it won't be "perfect"; I'll want to build another shortly after; and I could potentially mess something up; etc, etc. So, if I can get by with buying something a little less expensive like one of those tube sets that would be awesome.


    > I agree you should read more before you start putting things together.
    > OTOH, if the biggest/only hangup of you building your own frame is figuring out geometry, there's not necessarily anything wrong with copying an existing bike.
    A) The reason I am looking for a set and to just place an order is as a reason to actually get started. I bought my O/A setup over three years ago with the intention of building a bike, then had a number of excuses about why I shouldn't start one. Then, I start thinking about things and want a different type of bike. At least this way if I have it sitting in my garage it will kill me not to actually build it up. Then, I can work on the geometry/miter angles/etc. That's my plan at least.

    As far as why I will just "copy" geometry, the truth is that I haven't ridden enough bikes to know what I truly like (i.e. I have no idea how a 66 vs 66.5 degree head angle feels with everything else the same). So, I'm looking at a couple bikes I would like to own and will give it a go. I know I can just buy one of those Nukeproof frames for $350, but I really want to build one myself.


    > What are you using to miter the tubes?
    Planning on using a bench grinder, dremel, and cutoff wheels. That's what I have been using for my practice fillets. So, I don't think the thickness will be too much for my toolage.

    > At the risk of sounding like a d!ck, if you can't figure this one out, then you've got a lot more research to do.
    You're fine, I didn't specify what I'm actually doing. Going to be using a standard MTB tapered steerer tube fork (likely a Fox 34, but that could change. I have a Lyrik 160mm already, but think it will be too much for what I'm building). So, I'm thinking this is the one I would want: "46.4MM for 1.5/44mm headset"

    > Sleeving seat tubes is it's own whole rigamarole.
    I didn't even think about the whole dropper arrangement with the seatpost. I have a 30.9 dropper I was planning on using and it doesn't seem to be an option on Nova or Vari-Wall - am I blind? Or should I just plan on buying a new dropper?

    >The sliding dropouts can save you if you screw up a miter
    Those actually look like a good option! I am a bit concerned about the stainless, and they are pretty pricey, but as I look dropouts seem to be some of the most expensive.

    I also saw these from nova


    > If you're a first timer and a big/aggressive rider...
    I'm ~ 180 lbs and ride mostly in the Wasatch, but do ride pretty aggressive. I'll occasionally take my XC bike up to Deer Valley and hit some jumps or ride some rocky but not super techy stuff fast(my favorite trail at DV is Twist and Shout), but spend most of my time pedaling enduro style or at the park on my DJ. I have had a lot of fun on ~140mm trail bikes, but really want to push it on a hardtail. I am midpack with my friends who are all on FS bikes. I don't really know how "aggressive" I am.

    My practice tubing has been 0.035, which is ~0.9mm, and able to get the tubes to stick together through hammer blows.


    Thanks again for all the input!

  9. #9
    mtbr member
    Reputation: Feldybikes's Avatar
    Join Date
    Feb 2004
    Posts
    865
    A few more points (in no particular order, and with varying amounts of opinion vs. objective truth)

    • you can use a 30.9 dropper with a 31.6 seat tube if you use a shim.
    • I would not recommend stainless for your first bike. Silver is expensive and harder to work with.
    • Tabbed style dropouts give more room for error with mitering. These paragon ones are more expensive than what you selected but I find them easier to join.
    • Using a QR rear axle is even more forgiving than a thru axle because you can file the dropout a bit if it's crooked.
    • While using sliders can allow for some adjustability and forgiveness if you mess up a miter, it only allows for it in one dimension, so you need to be more careful that the dropouts are exactly parallel with each other.
    • Finally, and most importantly IMO, don't be fooled by benchtop strength tests. It's relatively easy to produce a fillet joint that you can smash with a hammer or crush in a vise and destroy the tubes yet have the fillet remain intact. However, at the same time, that joint would fail in fatigue after use. Most of the time when this happens, there will be a "warning" crack and the failure won't be catastrophic, but keep this in mind, especially with your first (few) frame(s).
    • You're probably investing 10s (a couple 100?) of hours into your first frame. While it makes sense to not start with the fanciest stuff possible, consider that when you make decisions on what tubing/frame parts to buy.

  10. #10
    mtbr member
    Reputation:
    Join Date
    Mar 2004
    Posts
    1,791
    This seat tube. Not super heavy duty, but you'll retire the frame before it dies. In a perfect world it would be heavier gauge. Fits either a 31.6 or a 30.9. I suggest using it to fit the 31.6 size and then beer can shim it, that way you don't really need to worry about reaming the 30.9 side to fit the 30.9 seat tube.

    https://www.cycle-frames.com/bicycle...-.9-x-560.html

    If you feel you need to move up to a heavier down tube than a 9-6-9 and feel braze enough to play with a bent down tube there is this option in a non-heat treated / air hardened tube.

    https://www.cycle-frames.com/bicycle...WITH-BEND.html

  11. #11
    mtbr member
    Reputation:
    Join Date
    Jul 2018
    Posts
    10
    Thanks for all the input. I think what I am going to do is this tubeset, and selecting the options of "46.4mm" headtube and the "dropper 33.5/31.8, 560".

    Also, Nova has these dropouts which seem to fit most of the suggestions addressed: adjustable, vertical dropouts, mild steel, and a brake mount. They are also quite a bit less than from Paragon.

    I will also have to figure out the cable guides...

    >This seat tube. Not super heavy duty, but you'll retire the frame before it dies.
    That makes a ton of sense, it's actually what I selected in the above.

    > You're probably investing 10s (a couple 100?) of hours into your first frame.
    True. Figuring I'll probably work through this one, then take my learnings into account for the next one where I'll spend a bit more money.

    Seriously, thanks. I am happy with this forum thus far - its a lot better than other online environments I have found!

  12. #12
    pvd
    pvd is offline
    mtbr member
    Reputation: pvd's Avatar
    Join Date
    Jan 2006
    Posts
    3,289
    What is a "tubeset"?

  13. #13
    mbtr member
    Reputation: scottzg's Avatar
    Join Date
    Sep 2006
    Posts
    4,966
    Quote Originally Posted by chasedehan View Post
    Also, Nova has these dropouts which seem to fit most of the suggestions addressed: adjustable, vertical dropouts, mild steel, and a brake mount. They are also quite a bit less than from Paragon.
    I wouldn't used hooded dropouts on a fillet brazed mtb frame, especially on a aggressive design and with sliding drops that work as a lever on the joint. There's not enough contact area. Those are for TIG, imo.

    Do you have a drawn/cad model of your frame? Can't order tubes until you can see the tube lengths and where the butts will fall. Those pre-bundled tube kits don't really save you any money and tend to be kinda straight and spindly for your application. If you don't know why you're choosing a tube then you shouldn't choose it. This is a necessary part of the planning process, and although it takes a long time to sort through all the tubes and understand their applicability... that's part of the fun. If you approach it like legos you'll end up ordering redundant parts or make mistakes you won't recognize until it's too late.





    I built my first 2 frames with no prior metalworking experience and no mentor. It was educational, but it was also stupid. I spent probably 250 hours researching parts and processes, reading manuals, practicing brazing, learning tools, and building fixtures. I'm glad i did it and i learned things that have served me well even now... but i didn't build another one until i could work under the tutelage of an expert. It was mostly a waste of time. That said, go in to this with the assumption you're gonna knock it out of the park and don't worry about a couple bucks here or there to get the right tool or frame bit.

    If you just want the experience of having put a 1st frame together i recommend building a urban bike. Something fun, with a rigid fork, horizontal drops, and a rowdy personality. Build it up with cheap kit cuz it doesn't matter, and go thrash and see if it breaks.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  14. #14
    mtbr member
    Reputation:
    Join Date
    Mar 2004
    Posts
    1,791
    Someone want to expand on the science of not brazing hooded drops?

    Plenty of pro builders (sure mostly road) have done brazed hooded drops.

  15. #15
    Moderator Moderator
    Reputation: Walt's Avatar
    Join Date
    Jan 2004
    Posts
    7,107
    Quote Originally Posted by shirk View Post
    Someone want to expand on the science of not brazing hooded drops?

    Plenty of pro builders (sure mostly road) have done brazed hooded drops.
    It's safe to do if you're good at making big, even, non-porous fillets. If you're not good at it (and it's tough on a small joint like that) then you won't get enough material in contact with the hood and it'll come apart.

    On a first frame I'd use something with tabs and slot/braze with brass. It's fairly hard to screw that up, though it won't look particularly nice on your first try.

    -Walt

  16. #16
    nrj
    nrj is offline
    mtbr member
    Reputation:
    Join Date
    Sep 2008
    Posts
    5
    Quote Originally Posted by scottzg View Post
    If you just want the experience of having put a 1st frame together i recommend building a urban bike. Something fun, with a rigid fork, horizontal drops, and a rowdy personality. Build it up with cheap kit cuz it doesn't matter, and go thrash and see if it breaks.
    +1

    A hard tail, while simple in concept, is probably one of the harder frames to build these days. Working with dropper posts, large tire clearance, and disc brakes is challenging for even experienced builders.

    A single speed road bike is probably the easiest to build. But I wouldn't even recommend that. Knowing how to fillet braze is only a tiny portion of the knowledge you need to build a solid frame.

    Your money would be best spent taking a class. It's more upfront cost, but if you plan to build more than one frame, it'll pay for itself in the long run.

  17. #17
    mbtr member
    Reputation: scottzg's Avatar
    Join Date
    Sep 2006
    Posts
    4,966
    Quote Originally Posted by shirk View Post
    Someone want to expand on the science of not brazing hooded drops?

    Plenty of pro builders (sure mostly road) have done brazed hooded drops.
    What walt said, basically. They're fine with breezer style dropouts where there's plenty of hood to build up a biggish fillet and the axle is close to the joints. The dropouts the OP linked have tiny hoods and the axle is a fair distance from the joints- it will be tricky to build up a big fillet and the long dropout works as a lever... i'd be nervous using those dropouts now, even though my brazing is pretty OK.
    Name:  NOV-DROP-SLDR-MS-DER-SET.jpg
Views: 207
Size:  41.7 KB
    Tabs are relatively easy- get a good fit, don't cook it, and fill up the junction with filler. They take me longer but whatever.

    Disclaimer- im a novice builder. (but i like doing destructive testing)
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  18. #18
    mtbr member
    Reputation:
    Join Date
    Jul 2018
    Posts
    10
    Ok, everyone has got me thinking about the intended application and it being a first frame.

    What I'm now thinking of doing is building a road bike as a first build. I already have left over road parts (only need a headset and fork) so it wouldn't really cost me much and would satisfy the initial build process. I generally like my current road bike so I already know the dimensions and could do it with only a couple small tweaks.

    I can get my "practice" out of the way and once I feel comfortable can move on to the frame I want.

    Couple other questions:
    1) Breezer dropouts - ok on this application? I won't be hucking anything on a road bike
    2) 858 or 969 on a road bike? My practice tubing is .9, and don't really want the weight on a road bike, but this is a first build...

    Thanks!

  19. #19
    mbtr member
    Reputation: scottzg's Avatar
    Join Date
    Sep 2006
    Posts
    4,966
    Quote Originally Posted by chasedehan View Post
    Ok, everyone has got me thinking about the intended application and it being a first frame.

    What I'm now thinking of doing is building a road bike as a first build. I already have left over road parts (only need a headset and fork) so it wouldn't really cost me much and would satisfy the initial build process. I generally like my current road bike so I already know the dimensions and could do it with only a couple small tweaks.

    I can get my "practice" out of the way and once I feel comfortable can move on to the frame I want.

    Couple other questions:
    1) Breezer dropouts - ok on this application? I won't be hucking anything on a road bike
    2) 858 or 969 on a road bike? My practice tubing is .9, and don't really want the weight on a road bike, but this is a first build...

    Thanks!
    Breezer dropouts are fine if you can build up a healthy fillet. The issue is that since hooded dropouts don't have much contact area with the tubes you need the brass's strength to make up the difference. IMO tabbed dropouts are easier at first, but the real issue with the sliding dropouts you posted before was a perfect storm of tiny hoods and the axle being at least an inch beyond the joints.

    The better your heat control the thinner tubing you can use. I'd go with 969 and lock it to poles with confidence. The weight difference is less than you think. Choosing the tube diameters and geometry gives you plenty of control over the bike's personality and flex.

    Consider doing a road bike with clearance for 38c tires. They're fun to descend on and designing around fat tires and chainrings is good for practice. No downside if you never mount any up.
    Last edited by scottzg; 6 Days Ago at 01:23 PM.
    "Things that are complex are not useful, Things that are useful are simple."
    Mikhail Kalashnikov

  20. #20
    Moderator Moderator
    Reputation: Walt's Avatar
    Join Date
    Jan 2004
    Posts
    7,107
    First frame = 9/6/9. 10th frame = probably also 9/6/9, if you're using Nova 4130. That stuff is, as Don Ferris once said "soft like whale snot" - I'm a long time pro and I won't use 8/5/8 unless it's heat treated/air hardening.

    Nothing you build will ever be as light as a $200 carbon frame off Alibaba. Accept that now, stop weighing your frames, and build stuff that will fit and ride right, and last you a long time.

    -Walt

  21. #21
    pvd
    pvd is offline
    mtbr member
    Reputation: pvd's Avatar
    Join Date
    Jan 2006
    Posts
    3,289

  22. #22
    mtbr member
    Reputation:
    Join Date
    Mar 2004
    Posts
    1,791
    Don't waffle, just build, break, repair, and build again.

    If you WANT a mountain bike build it. Build a rowdy ht out of the tubes available from Nova.

    I bought a lugged set and tubes for my first bike...it's still sitting in a box slowly rusting away.

    Don't over think, just get started.

  23. #23
    mtbr member
    Reputation:
    Join Date
    Jan 2006
    Posts
    42
    Errr,
    i would like to repeat Mr. Verdone's (pvd) question (this phrase seems to surface all the time within the fame building forums, along with the "lightwaight" nightmare)

    Well...?

Similar Threads

  1. REEB Tubeset
    By adarn in forum Frame Building
    Replies: 14
    Last Post: 09-15-2014, 07:37 AM
  2. Replies: 4
    Last Post: 07-27-2011, 06:11 PM
  3. Tubeset advise for a 9yo's MTB
    By dperalta in forum Frame Building
    Replies: 13
    Last Post: 01-04-2011, 02:17 PM
  4. Steel tubeset mfg?
    By Fasttrak in forum Custom Builders & Other Manufacturers
    Replies: 5
    Last Post: 07-25-2006, 12:51 PM
  5. Frustrated re moto lite sizing & shock / tubeset differences
    By Haager the Horrible in forum Titus
    Replies: 27
    Last Post: 05-18-2006, 05:06 PM

Members who have read this thread: 80

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

THE SITE

ABOUT MTBR

VISIT US AT

mtbr.com and the ConsumerReview Network are business units of Invenda Corporation

(C) Copyright 1996-2018. All Rights Reserved.