The Blockhead

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I have had this idea in my head for a while a whole bike made out of square and rectangular tubing. I plan on making the frame, fork, bars, and seat post in such a fashion. It will be a 26" bmx cruiser.

Pics below are the first steps.
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Start with a bmx shell and a head tube, time to put the round peg in the square hole!
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I will make you fit!!! A hammer was used too......
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Got it in there....
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Using the mill to make it all level...


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A little filing and a bearing race went in with little force...
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90 degreish....
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I could not find a tube the right size so I have to make a box out of plate...
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made a shell for the shell, not 100% but it should work...

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Mocked up so far, not bad for one morning. Not married to the big down tube and looks a little squished, I may change it....
 
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I have had this idea in my head for a while a whole bike made out of square and rectangular tubing. I plan on making the frame, fork, bars, and seat post in such a fashion. It will be a 26" bmx cruiser.

Pics below are the first steps. View attachment 144773 View attachment 144773

Start with a bmx shell and a head tube, time to put the round peg in the square hole! View attachment 144774

I will make you fit!!! A hammer was used too...... View attachment 144775

Got it in there....
View attachment 144776

Using the mill to make it all level...


View attachment 144777
A little filing and a bearing race went in with little force...
View attachment 144778
90 degreish....
View attachment 144779
I could not find a tube the right size so I have to make a box out of plate... View attachment 144780 View attachment 144781

made a shell for the shell, not 100% but it should work...

View attachment 144782

Mocked up so far, not bad for one morning. Not married to the big down tube and looks a little squished, I may change it....
You sure have a nice shop. Wish I had access to it:crazy:. Box tube designs are interesting to me. Was discussing square tube not so long ago. I prefer the 'diamond' look of the Schwinn Z-Force frame. Realize the mitering isn't as easy.
Hope you have fun working on it... know I would!
 
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I love the idea, but I have to ask: Is it still called tube if it is square?
Also, this
View attachment 144792
Yeah that has some round tubes, visible as it where. Close! but not totally from Bizzaro World. A stroker two wheeler is close too, so close...... And a tube is any shape that is not solid, round, square, rectangular, triangular etc.
 
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You sure have a nice shop. Wish I had access to it:crazy:. Box tube designs are interesting to me. Was discussing square tube not so long ago. I prefer the 'diamond' look of the Schwinn Z-Force frame. Realize the mitering isn't as easy.
Hope you have fun working on it... know I would!
Well a long time to acquire and lots of $$$$, it makes taking ideas to ridable much easier and repeatable... But up frame shop to make stuff for prototyping for our brand, skill building, and to make some fun bikes too of course. Looking to get a lathe next.

index.php


Z frame, you Z one now.....
 
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Polished 90° square tube frames look too much like old department store clothing racks to me. Could be my prejudice being dragged into those places as a kid all the time.

Square tube with a higher side profile.
Schwinn Aluminum Z-Force.jpg


The CW Phaze 1 kinda scares me. Not sure I'd want that down tube coming back at me after falling off or getting tangled up.
CW Phaze 1.jpg
 
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IMG_1545.JPG

Going with the smaller down tube, looks better to me.
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drilled out the bb and head tube so I could bung weld them in place....
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These will be covered up by the main frame tubes...
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BB shell all welded up....

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Made some shims for the seat tube to take a seat post.
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Seat post will be made soon... have to make it strong because it is so small....
 
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Time to work on the rear end of the bike, making the stays for me, is the trickiest part. I made a tool a while back to make some Redline Squareback clones in 26". Since I had the dropouts and got some rectangular tubing, it made sense to use this setup for this bike too. I used this tool to bend both the seat and chain stays by hand. I used a cheater bar on the chain stays. Got is all tacked together this morning, looks pretty cool, I was worried it would be super ugly (it may still be). Weighs a ton! I'm used to riding 45 pound bikes in the mountains so the weight won't be that big of a deal I think. We'll see......

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MattiThundrrr

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I like it. Don't worry, it isn't ugly from the side, just has a rough attitude! I'm not sold on the rear end though. Maybe I just need to see how it looks with a wheel in there
 
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I like it. Don't worry, it isn't ugly from the side, just has a rough attitude! I'm not sold on the rear end though. Maybe I just need to see how it looks with a wheel in there
Oh I'm not. It is a wierd idea so it will not confrom to "bmx" style 100%. I wanted to see what it would look like from my head to reality, fork, bars etc will complete the Bozzaro World ensemble, so who knows? The z frame was made at the request of a friend, I am still tripping over the thing :)
 
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After tacking the frame you have to go over it and get it straight. The fixture, while super trick does not automatically make the frame straight. Even high a end bike line like Santa Cruz has to go through this process. While tacked together, one can just tweak it by hand. You finish welding outside of the jig and then you'll have to take it back over to the table and have another go at it with a pry bar of some sort, I have found a 2x4 works well... :)
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end bike
 
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I’m don’t typically care for square tubed bikes, but dang!
This is a pretty cool concept and it works great so far!

Keep up the good work!


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Thanks! It is a "we'll see" sort of thing. Don't think it has been done yet like this but who knows. :)
 
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Got the fork tacked together this morning, had to stew on it for a day or two before I made my cuts. Found some super thick square tubing in a barrel in my yard that will make a stout and super heavy fork. My general rule is to use what I have laying around before I spend money. I have sheds full with 100 milk crates full of parts, chances are I have something that will work, digging takes time. If it bends, I can go back and make a 4130 version. Second picture is to make sure
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I have wheel/tire clearance.
 
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Got the fork mostly done today. My welds are going from shameful to just mildly embarrassing, so improvement! Steer tube will need to be threaded down, and a few more small pars need to be made for the frame. Clean up and some finish work will be last after I make the bars and seat
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post.
 

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