# Titanium dirt jumper frame build



## O'Neill6 (Jul 9, 2021)

Hello all,

I'm brand new to this forum and to frame building, so go easy on me.
Also, let me know if I'm posting this in the wrong place.

As stated in the title, I am hoping to build up a titanium framed dirt jumping bike. I am looking for any and all criticism and advice on this idea. I will also list below a number of questions that I will absolutely love to have you guys answer. Thanks.

I work at an aircraft tube bending facility and have access to quite a bit of scrap titanium. It will cost me nothing to acquire the main tubes, but I plan on Buying the BB, steer tube and other necessities from Paragon Machining. I don't know how to weld Titanium, but the welder at my shop agreed to do it for me. All and all, the frame shouldn't cost too much $ out of pocket.

Also, just for more information, I weigh about 130 and can make fairly smooth landings off jumps.

1 I can get free 3/2.5 class 1 type 1 CWSR 105 titanium tubing from my work. It is not butted. Is that an acceptable material? I know grade 9 ti is best, but will other grades work too?

2 What wall thickness is best for the respective frame tubes? The main one's at my work are .022" .025" .035" .044". I assume the thicker is the better, but at the same time I am trying to make this as light as possible.

3 What are the best ODs for the respective frame tubes?

Sorry for being such a newbie,

Thank you


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## JackOfDiamonds (Apr 17, 2020)

The tubes can't be spec'd without knowing something about the design. If the frame is bigger or smaller it makes a huge difference in what tubes are needed. Besides I don't know much about dirt jumper frames but to get in the ballpark I would find an existing steel one and copy the tube sizes and just go twice as thick with the titanium. 

You aren't going to get a super-optimized frame out of this project. You will have to overbuild, or else you are going to have failures, because the only way not to overbuild is to underbuild first and figure out where the failures are over time. Without a design to copy, you will have to overbuild. I'm not discouraging you because if I had access to Ti tubing I would probably try to build a frame too, just be happy with whatever you end up with as a unique project.


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## dr.welby (Jan 6, 2004)

You can compare to commercially available bike-sized tubing: Nova Cycles > TUBES TITANIUM > MAIN TUBES


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## O'Neill6 (Jul 9, 2021)

dr.welby said:


> You can compare to commercially available bike-sized tubing: Nova Cycles > TUBES TITANIUM > MAIN TUBES


Awesome! Yeah it looks like 0.035'' wall is fairly common. Do you guys think 0.035'' is fine or maybe a little heavier like 0.040" or 0.044". I realize that the thicker the stronger, but I'm trying to find the thinnest and lightest I can go without worrying about my frame snapping or bending on me.


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## pvd (Jan 4, 2006)

Material choice is not very important on a bicycle.
Focus on good design. Few bother with doing that.


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## dr.welby (Jan 6, 2004)

pvd said:


> Material choice is not very important on a bicycle.


Are you sure?


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## pvd (Jan 4, 2006)

dr.welby said:


> Are you sure?


Carbon fibers are fine. That was an engineering and supply problem.
I just produced a bike last week that you might like that uses the same bar design...with a different tube spec.









2021 TIE Advanced X1 All-Road | Peter Verdone Designs






www.peterverdone.com


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## O'Neill6 (Jul 9, 2021)

pvd said:


> Material choice is not very important on a bicycle.
> Focus on good design. Few bother with doing that.


I think for sure design is very important. But material does also play a major role. They kinda go hand in hand.


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## O'Neill6 (Jul 9, 2021)

pvd said:


> Carbon fibers are fine. That was an engineering and supply problem.
> I just produced a bike last week that you might like that uses the same bar design...with a different tube spec.
> 
> 
> ...


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## pvd (Jan 4, 2006)

O'Neill6 said:


> I think for sure design is very important. But material does also play a major role. They kinda go hand in hand.


If you progress in all of this you will learn what I've said.


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## O'Neill6 (Jul 9, 2021)

pvd said:


> If you progress in all of this you will learn what I've said.


Yeah, no worries man. I think I just miss interoperated what you said earlier. I like your bike, did you make it?


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## pvd (Jan 4, 2006)

O'Neill6 said:


> I like your bike, did you make it?


Of course. There is a lot of information about bike design on my site. You would do well to review it.


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## O'Neill6 (Jul 9, 2021)

pvd said:


> Of course. There is a lot of information about bike design on my site. You would do well to review it.


Will do. Thanks.


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## thedudeman (Nov 10, 2006)

I think it sounds like an awesome project! 
I was looking into it for a bmx frame, and I think stiffness will be a consideration vs a frame in chromoly of similar diameters/ thicknesses.
Mike Laird makes ti frames for jumping and BMX. He might be more helpful….
If it was mine, I’d start at 1.5x.035 TT, 1-3/4x .040 dt and at least .75 stays, preferably bigger like .875x.035. Then see if anyone on here freaks out about it being too weak. 
I’d skip the whole forward geometry bullshit unless you want a dirt jumper that is light but handles like a semi truck.


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## .WestCoastHucker. (Jan 14, 2004)

dr.welby said:


> Are you sure?


karma...


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## O'Neill6 (Jul 9, 2021)

thedudeman said:


> I think it sounds like an awesome project!
> I was looking into it for a bmx frame, and I think stiffness will be a consideration vs a frame in chromoly of similar diameters/ thicknesses.
> Mike Laird makes ti frames for jumping and BMX. He might be more helpful&#8230;.
> If it was mine, I'd start at 1.5x.035 TT, 1-3/4x .040 dt and at least .75 stays, preferably bigger like .875x.035. Then see if anyone on here freaks out about it being too weak.
> I'd skip the whole forward geometry bullshit unless you want a dirt jumper that is light but handles like a semi truck.


Yeah, I was putting my money on the 0.035 wall thickness. I was thinking the seat stays could be 0.625 and chain stay 0.75. I was putting the top tube to be maybe 1.375 and down tube to be 1.5, both at .035 wall.

I wonder if it would be better to increase the seat and chain stays to 0.044 wall.

What do you guys think? I'm getting to the point of ordering parts and such so any advice would be appreciated.


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## pvd (Jan 4, 2006)

O'Neill6 said:


> What do you guys think? I'm getting to the point of ordering parts and such so any advice would be appreciated.


You haven't shown any design. There isn't much to comment on. Do you have a drawing, show. A fixture? Do you have finishing tools, prove. Doing that before ordering parts would make sense. Design review is good work.


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## O'Neill6 (Jul 9, 2021)

pvd said:


> You haven't shown any design. There isn't much to comment on. Do you have a drawing, show. A fixture? Do you have finishing tools, prove. Doing that before ordering parts would make sense. Design review is good work.


I do not have any paper drawings yet. Currently I have a picture of a Marin Alcatraz frame that I am using for a rough design. I just have some notes and numbers on it. Included is a picture of it.

I have a mental picture of what I want, but I just want to make sure I can acquire enough material before going further. Narrowing down my material dimensions to a simple exhaustive list will help speed up the process. That's mainly why I seek your guy's advice right now.

If you think I should go right into the drawing and design of the frame, then I can do that. I'll probably end up using CAD

Sorry for the length of this message, but for the sake of argument, let's assume I'm going to closely model Marin's Alcatraz for my frame size and geometry. Given that, do you think my proposed material spec's are adequate?


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## pvd (Jan 4, 2006)

O'Neill6 said:


> ....let's assume I'm going to closely model Marin's Alcatraz for my frame size and geometry.


Those are sold very cheap. Buy one of those.


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## JackOfDiamonds (Apr 17, 2020)

Copying an existing frame is a great idea, and very solid way to start. Copying a frame is the best way to prevent disaster and ensure your design is reasonable, and it is also the way to guarantee your end result doesn't need to exist, because you could have just used the frame you are copying, and saved a lot of time and money and had a more assured outcome. 

I do hope you realize that you are going to have spent 3X more than you thought you would, just to have a copy of a frame you could have bought, and probably a slightly worse copy at that, and that's a pretty good outcome. And you are going to immediately want to build a second frame that fixes the errors or shortcomings of the first. 

If you are down with all that then have fun, in all seriousness. It doesn't have to make sense if it makes you happy.


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## O'Neill6 (Jul 9, 2021)

JackOfDiamonds said:


> Copying an existing frame is a great idea, and very solid way to start. Copying a frame is the best way to prevent disaster and ensure your design is reasonable, and it is also the way to guarantee your end result doesn't need to exist, because you could have just used the frame you are copying, and saved a lot of time and money and had a more assured outcome.
> 
> I do hope you realize that you are going to have spent 3X more than you thought you would, just to have a copy of a frame you could have bought, and probably a slightly worse copy at that, and that's a pretty good outcome. And you are going to immediately want to build a second frame that fixes the errors or shortcomings of the first.
> 
> If you are down with all that then have fun, in all seriousness. It doesn't have to make sense if it makes you happy.


Agreed. I understand that this will cost quite a bit. I've made some other crazy contraptions before as well. Included is a picture of an electric monowheel that my brother and I build last summer. This one cost way more then we expected, thankfully we had it sponsored by our uncles and other small business. I'm mainly doing the bike build to have fun while gaining experience and new knowledge. I'm still pretty young (age 18) and hope to do this type of stuff throughout my life. I just figured, I'd start sooner than later.

I'm going to use the Alcatraz as a rough design to model, but change up some of the geometry's to suit me better.


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## slapheadmofo (Jun 9, 2006)

Screw the dirt jumper - I want one of those!


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## O'Neill6 (Jul 9, 2021)

slapheadmofo said:


> Screw the dirt jumper - I want one of those!


I know, it was a wild project. It's a ton of fun to ride.


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## .WestCoastHucker. (Jan 14, 2004)

slapheadmofo said:


> Screw the dirt jumper - I want one of those!


The original prototype is from South Park. Mr Garrision approved..


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## slapheadmofo (Jun 9, 2006)

O'Neill6 said:


> I know, it was a wild project. It's a ton of fun to ride.


I'll bet.  

Tell me about that tire.


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## O'Neill6 (Jul 9, 2021)

slapheadmofo said:


> I'll bet.
> 
> Tell me about that tire.


We were trying to get one custom made, but no beano. We actually ended up using 4 26'' Schwinn tires, cut and screwed.

I don't mean to be pushy or rude, but are any of you guys cool with my current DJ design? As far as material spec's?

I going to try to talk to my boss tomorrow to see if I can start pulling material.


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## JackOfDiamonds (Apr 17, 2020)

I don't really do dirt jumping, so I can't give any feedback about the frame. 0.035 is probably going to be fine for the tubes. Where are you going to get the head tube, BB, and dropouts?


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## O'Neill6 (Jul 9, 2021)

JackOfDiamonds said:


> I don't really do dirt jumping, so I can't give any feedback about the frame. 0.035 is probably going to be fine for the tubes. Where are you going to get the head tube, BB, and dropouts?


I was planning on getting them from Paragon Machining. And I'm still debating on whether to go with 0.044 for the seat and chain stays.


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## .WestCoastHucker. (Jan 14, 2004)

O'Neill6 said:


> I don't mean to be pushy or rude, but are any of you guys cool with my current DJ design? As far as material spec's?


i've only played this custom made dirt jumper game twice with cro-mo based around 24" wheels and a fork modded down to 30" travel. i can share my drawings and specs, but i don't know if they would be helpful in any way...


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## O'Neill6 (Jul 9, 2021)

.WestCoastHucker. said:


> i've only played this game with cro-mo based around 24" wheels and a fork modded down to 30" travel. i can share my drawing and specs, but i don't know if they would be helpful in any way...


Yeah, I understand. No worries.


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## .WestCoastHucker. (Jan 14, 2004)

O'Neill6 said:


> Yeah, I understand. No worries.


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## O'Neill6 (Jul 9, 2021)

Nice, thanks, BTW what program do you use for that? I just use Autodesk's Fusion 360, but that's manly for 3d printing.


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## .WestCoastHucker. (Jan 14, 2004)

pretty sure it was soildworks


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## O'Neill6 (Jul 9, 2021)

.WestCoastHucker. said:


> pretty sure it was soildworks


Cool. I'll check it out.


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## O'Neill6 (Jul 9, 2021)

Okay guys,

I have a question regarding wall thickness again.

I'm trying to do my best to make this bike frame to the materials I have, not the other way around. Right now I'm covered on the front triangle of the frame, I've just run into some trouble with the chain and seat stays. I have decided to go with both of them at 0.75" OD and (preferably) 0.044" wall thickness. The problem is that my work only uses 0.027" and 0.052" wall. What do you guys think about that? Would it work to make the seat and chainstay with the respective wall thicknesses? (one at 0.027" and the other at 0.053). I would think that would seem to balance out the differences'. If you think it won't work out, I guess I could always just buy them from Titanium Joe.

Any thoughts or comments are appreciated.

Thanks


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## JackOfDiamonds (Apr 17, 2020)

3/4 is pretty big. I think either would be ok but I would probably err on thicker. I think bmx chainstays are usually 3/4 by 0.035". You could also mix and match.


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## O'Neill6 (Jul 9, 2021)

Ok, yeah. I suppose something like that would be ideal. I think I might just order the right material. I don't know.


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## Cord (Dec 10, 2006)

It’s your first frame, you’ll find lots of things you will do differently if given another chance, for that reason I’d go with the cheapest option. i.e. use material you have. I think 3/4 it’s a good sturdy tube, so I’d be happy to go with the thin wall. If that worries you, mix and match.


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## O'Neill6 (Jul 9, 2021)

Cord said:


> It's your first frame, you'll find lots of things you will do differently if given another chance, for that reason I'd go with the cheapest option. i.e. use material you have. I think 3/4 it's a good sturdy tube, so I'd be happy to go with the thin wall. If that worries you, mix and match.


Well said, I'm sure there will be quite a few things on this bike that I would have liked to have done differently by the time it's done.

I think I'll try mix and matching a little.


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## iRider (Nov 15, 2005)

Cool project! 

As an owner of a Commencal Absolut DJ Ti, there are a few things I want to mention that might help you with the project. 
The Commi frame is 1500 g for a size small, so super light, with a Spanish BB (pain in the a$$). While I love this frame, I would not use it for bigger DJ-ing. It is my pump track bike, so it is fine, but even here the flex can be felt. While riding this is usually not an issue, but I have to run the chain super tight as I had it falling off from the flex under cornering over some bumps. DOs have screws to adjust the chain slack, which I think is necessary as the axle would shift in the DOs otherwise. Not sure if it is the smooth Ti surface that causes this, but never had this on a steel DJ.
From my experience with the Commi, I would want a frame that has at least 500 g more material and some gussets and/or ovalized or larger tubes to reduce flex in the BB area if I would be serious about DJ-ing it.


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## dr.welby (Jan 6, 2004)

Does your work have the tools to bend 3/4 x 0.027" ti tubing without it wrinkling?


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## O'Neill6 (Jul 9, 2021)

iRider said:


> Cool project!
> 
> As an owner of a Commencal Absolut DJ Ti, there are a few things I want to mention that might help you with the project.
> The Commi frame is 1500 g for a size small, so super light, with a Spanish BB (pain in the a$$). While I love this frame, I would not use it for bigger DJ-ing. It is my pump track bike, so it is fine, but even here the flex can be felt. While riding this is usually not an issue, but I have to run the chain super tight as I had it falling off from the flex under cornering over some bumps. DOs have screws to adjust the chain slack, which I think is necessary as the axle would shift in the DOs otherwise. Not sure if it is the smooth Ti surface that causes this, but never had this on a steel DJ.
> From my experience with the Commi, I would want a frame that has at least 500 g more material and some gussets and/or ovalized or larger tubes to reduce flex in the BB area if I would be serious about DJ-ing it.


Wow, that doesn't sound that great about the chain falling of. Funny that you mentioned it because I actually was thinking about the same thing. I found this dropout and might possibly try to make/buy one. I should hopefully help with that problem.


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## iRider (Nov 15, 2005)

O'Neill6 said:


> Wow, that doesn't sound that great about the chain falling of. Funny that you mentioned it because I actually was thinking about the same thing. I found this dropout and might possibly try to make/buy one. I should hopefully help with that problem.


Those look like some great DOs! 
I initially ran the chain fairly slack as I did not want too much strain on the bearings/chainring, so that might have contributed to it. But it was not so slack to slap the chainstay under normal riding, but you could hear it hitting in some bumpy corners. After it fell off once I tightened it so the crank does not spin freely anymore, which I think is acceptable for riding pumptracks.
FWIW: The flex is not so bad that the tire would hit the stays, but I also ride fairly stiff wheels.

Could you reinforce the BB area to make it stiffer in your design? Ovalize the DT maybe?


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## O'Neill6 (Jul 9, 2021)

iRider said:


> Those look like some great DOs!
> I initially ran the chain fairly slack as I did not want too much strain on the bearings/chainring, so that might have contributed to it. But it was not so slack to slap the chainstay under normal riding, but you could hear it hitting in some bumpy corners. After it fell off once I tightened it so the crank does not spin freely anymore, which I think is acceptable for riding pumptracks.
> FWIW: The flex is not so bad that the tire would hit the stays, but I also ride fairly stiff wheels.
> 
> Could you reinforce the BB area to make it stiffer in your design? Ovalize the DT maybe?


Actually, I might be able to ovalize the DT. I didn't think about that. Are you thinking the whole thing or just the bottom portion of it?

After hearing quite a few stories of ti frames flexing a lot, I'm tempted to put some gussets on the rear of the frame. That might help a little.


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## O'Neill6 (Jul 9, 2021)

dr.welby said:


> Does your work have the tools to bend 3/4 x 0.027" ti tubing without it wrinkling?


Sorry, I missed your message. I don't know how.

Yeah, we can pretty much bend anything from 1/4'' to 4'' without wrinkling or damaging it.

Is 0.027'' wall good wall thickness for the frame. I was thinking maybe thicker, like 0.035''. But if 0.027'' is fin I may actually try that, as there is plenty of it at my work.


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## dr.welby (Jan 6, 2004)

O'Neill6 said:


> Sorry, I missed your message. I don't know how.
> 
> Yeah, we can pretty much bend anything from 1/4'' to 4'' without wrinkling or damaging it.
> 
> Is 0.027'' wall good wall thickness for the frame. I was thinking maybe thicker, like 0.035''. But if 0.027'' is fin I may actually try that, as there is plenty of it at my work.


I think it's too thin too, but if your employer didn't have the right equipment and you had to DIY it that would be another reason to go thicker.


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## O'Neill6 (Jul 9, 2021)

dr.welby said:


> I think it's too thin too, but if your employer didn't have the right equipment and you had to DIY it that would be another reason to go thicker.


Yeah, sounds good. Right now I'm on the fence between 0.035'' and 0.039'' wall for the stays. Off the bat, I don't plan on using any gussets, so maybe 0.039'' is better


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## .WestCoastHucker. (Jan 14, 2004)

i'd go for the 0.039" for a jump bike. it's gonna be pulling lots of G's pretty often. noodly frames suck for jumping...


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## O'Neill6 (Jul 9, 2021)

.WestCoastHucker. said:


> i'd go for the 0.039" for a jump bike. it's gonna be pulling lots of G's pretty often. noodly frames suck for jumping...


Alright, makes sense. It would defiantly suck to build the whole thing only to have the frame be too flexible. I'll go with 0.039''.


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## Cord (Dec 10, 2006)

if you are buying .039, wouldn't you just use the .044 you already have?


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## O'Neill6 (Jul 9, 2021)

Cord said:


> if you are buying .039, wouldn't you just use the .044 you already have?


Well, because I didn't know all the specific sizes needed to build a frame at the start. My work doesn't use 0.044 wall that much for 0.75, and when we do it's usually customer furnished with not much left over.


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## iRider (Nov 15, 2005)

O'Neill6 said:


> Actually, I might be able to ovalize the DT. I didn't think about that. Are you thinking the whole thing or just the bottom portion of it?
> 
> After hearing quite a few stories of ti frames flexing a lot, I'm tempted to put some gussets on the rear of the frame. That might help a little.


I was thinking just the bottom portion, and maybe also the seat tube?


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## uncajohn (Jan 17, 2006)

pvd said:


> Carbon fibers are fine. That was an engineering and supply problem.
> I just produced a bike last week that you might like that uses the same bar design...with a different tube spec.
> 
> 
> ...


It looks like you have placed the grips (with the steering bar / stem combination) at the same distance or close with your warbird bike (I don't make bicycles. I make weapons systems. | Peter Verdone Designs)...


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## O'Neill6 (Jul 9, 2021)

Hey guys,

Sorry for seemingly have disappeared for a while. 

I've got an update and question on my Ti DJ build.

I did end up deciding to build the bike after all. I currently have the majority of the parts and am working on the front triangle right now. I opted to use a fixture method similar to what my work uses. It's done by 3D printing blocks that hold the respective tubes in their proper places for mitering and tacking. Feel free to ask about or criticize my methold.I've had a major dalay with the down tube being bent, but I finally just got it back last week. Included below are some pictures of my progress as well as my most pressing question.

I'm wondering which tube I should miter. I have the top and down tube meeting at the head tube. They have a bit of an overlap, so mitering at least the down or top tube is a must. I was initially thinking of coping the top tube so that it fits on top of the top tube. But I'm not totally positive if I should do that. You guys have a lot of knowledge and experience in this, so I thought that you'd be able to shed some light on my lack of it.

Thanks and happy Thanksgiving for those in the US!


P.S. In case you care, I actually changed my mind and modeled this off the Santa Cruz Jackal and no the Alcatraz.



















I'm not totaly sure which tube I should miter to make room for both. I'm thinking about cutting a spot in the top tube so that it fits nicly together with the down tube, and then weld the seam where the two tubes meet.









Here's a close up of how the fixtures work.


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## bentmettle (Jul 2, 2018)

it looks like, and you can correct me if my glasses aren't working too great, that you have your down tube modeled so that it's mating in a tapered portion of your headtube. Does that head tube not have two discrete diameter sections intended for mating to the top and down tobes?

Why not just pull a bit of distance between the top and down tube and eliminate all the work of that joint?


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## O'Neill6 (Jul 9, 2021)

bentmettle said:


> it looks like, and you can correct me if my glasses aren't working too great, that you have your down tube modeled so that it's mating in a tapered portion of your headtube. Does that head tube not have two discrete diameter sections intended for mating to the top and down tobes?
> 
> Why not just pull a bit of distance between the top and down tube and eliminate all the work of that joint?





bentmettle said:


> it looks like, and you can correct me if my glasses aren't working too great, that you have your down tube modeled so that it's mating in a tapered portion of your headtube. Does that head tube not have two discrete diameter sections intended for mating to the top and down tobes?
> 
> Why not just pull a bit of distance between the top and down tube and eliminate all the work of that joint?



Actually, I think you might be right. I'm using a 100mm head tube from paragon. Below are some pictures. It seems to have simi straight portions, but I don't know. At least for the top tube.


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## bentmettle (Jul 2, 2018)

the step file I grabbed sure looks tapered. How are people mitering for that? I assume something more involved than a holesaw?


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## O'Neill6 (Jul 9, 2021)

bentmettle said:


> the step file I grabbed sure looks tapered. How are people mitering for that? I assume something more involved than a holesaw?



I plan on just using a file. A wise man once said that you could pretty much make anything with a file and enough time.


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## O'Neill6 (Jul 9, 2021)

Hey guys,

I know it's been a while, but just wanted to share some photos of my finished frame.

This was defiantly a difficult bike for a first frame build, but I learned quite a bit.

It weighs in at only 3.09 lbs. I can't seem to find any other DJ frames any lighter than that. I was trying to make the frame as light as possible, and so far I'm pretty pleased. Love to hear if anyone knows of any lighter DJ frame builds.


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## AdamR83 (Jan 21, 2021)

Beautiful! Great work. You must be so pleased!


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## dr.welby (Jan 6, 2004)

Nice to see some DJ-specific design, very clean execution!


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## stuartm2 (Mar 5, 2020)

O'Neill6 said:


> View attachment 1958471
> 
> 
> View attachment 1958474
> ...


Those fixtures look really interesting. Looks like they're 3D-printed plastic. What's the story with them? Did you tack the joints in them too, or was it just to get the mitres right?


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## O'Neill6 (Jul 9, 2021)

stuartm2 said:


> Those fixtures look really interesting. Looks like they're 3D-printed plastic. What's the story with them? Did you tack the joints in them too, or was it just to get the mitres right?


Hey stuartm2

Sorry for the late reply. I don't remember getting a notification.

Yeah, so I just used my CAD model of the bike to 3D print the fixers for it. They were especially helpful for the mitering.

We were able to tack most of the frame without issue while still in the fixture, but after the tack, just took it out and finished the weld. It would defiantly get too hot and melt the plastic.


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## stuartm2 (Mar 5, 2020)

Thanks, I don't think I've seen a jig approach like this before and was intrigued. I used 3D-printed fittings with my home-made jig (using extruded aluminium beams) but found they melted during tacking and plan to remake them with aluminium before the next build now that I've got a small lathe. The melting could easily be explained by my poor welding skills though


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## O'Neill6 (Jul 9, 2021)

Yeah, the one holding the BB assembly had a little melt, but not enough for us to be concerned about.

It seems like the majority of frame builders use extruded aluminum for the fixtures. The way I'm set up, it just made more sense to at least try the 3D printed way. And it seemed to work out well. My only complaint would be that it was hard to see the underside of the tube when mitering.


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