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warren
human power expert

4230 Posts

Posted - 11/28/2011 : 09:46:01

Here's the frame with the front fork mounted, sitting in the frame jig to ensure everthing is straight before I complete the brazing on the head tube and the joint that will be drilled out for the rear pivot.

Here's the rear suspension pivot shell, bearings, axle, and the clamp stock that will be used to fasten the axle to the rear stays. I was able to source all of the tubing from my box of tubing cutoffs, and the bearings were left over from an aborted project I was contemplating several years ago.
I have often joked that my hobby is making big pieces of metal into smaller ones, fortunately some of those smaller pieces do end up getting used.

I fully brazed the joint and then used a fairly standard bi-metal hole saw to cut a hole in the joint of the chrome moly tubing. It's important to take your time and use plenty of cutting oil to prevent dulling the hole saw teeth.
The frame was clamped in place on my drill press, and I used a level to ensure that the frame was perfectly perpendicular to the drill press.

After spending a lot of time attempting to make sure the pivot shell was straight using the frame jig, a small square, a micrometer, and my eyeball, I tack brazed the shell into the frame.
Probably not perfect but for using rudimentary tools in a cold garage it's fine.

Here's the bearing and axle in the frame.

Next it's time to bend the rear stays.

-Warren.

warren
human power expert

4230 Posts

Posted - 11/29/2011 : 19:32:55

Tubing Roller demonstration

http://youtu.be/ahE4tqRLZRg

-Warren.

Larry Lem
human power supergeek

South Sandwich Islands
1971 Posts

Posted - 11/29/2011 : 20:01:40

I was wondering if you have to be careful to keep the tube from rolling "sideways" and accidentally making a 3-D bend instead of a 2-D bend. Do the 3 rollers keep the tube lined up in one plane? I guess so.

Larry Lem

warren
human power expert

4230 Posts

Posted - 11/30/2011 : 05:42:56

It does roll a bit to one side, but that does not seem to matter. I did correct it ever couple rolls on the first couple tubes, but once the bend gets to a certain diameter it stops rolling to the side.

-Warren.

Speedbiker
human power supergeek

USA
1996 Posts

Posted - 11/30/2011 : 07:17:01

Will the rear suspension removeable/rebuildable?

warren
human power expert

4230 Posts

Posted - 11/30/2011 : 08:53:04

Yes, the axle can be pushed out to remove the rear suspension. The chain stays will be held to the axle by the tube clamp method.

warren
human power expert

4230 Posts

Posted - 12/02/2011 : 17:13:20

I'm looking at wheels because I will need to re-lace them anyway to fit the drum brake up front. I'm thinking that the 1.25" wide rims on my MTB currently may be too narrow for the Schwalbe Fat Frank tires I just ordered from Amazon.

Does anyone have an opinion on these Weinmann dm30 26 x 2 wheels? Are they really 2" wide or 1.75"?
http://www.niagaracycle.com/product_info.php?products_id=15731

I now have a pile of socket shoulder screws and matching brass sleeve bearings for the shock absorption side of the rear suspension. I'm waiting for some tubing to mount the bearing in.

Hopefully I'll get some time this weekend for some quality building!

-Warren.

Edited by - warren on 12/02/2011 17:13:34

warren
human power expert

4230 Posts

Posted - 12/05/2011 : 16:47:04

I put the bike back in the jig, and cut the rear stay tubes to fit between the pivot bearings and the Surly dropouts.

It was very difficult to ensure everything was straight with all the curved tubes. I'm not too concerned about perfection, but it would be really nice if the wheels were straight with the frame. Even with a frame jig this is difficult.

I brazed the chain stay tubes to the dropouts.

Next I carefully measured and measured and measured again before drilling the hole in the chain stay for the pivot tube clamp. I put it all together in the jig and a small miracle occurred. It all slid together. I tack brazed the tube clamp into place. In this picture you can see the axle sticking out of the tube clamp. I will slit the chain stay on the bottom and braze a clamp in place which should hold the axle firmly.

I need to take it all out of the jig, put wheels back on it and eyeball it to make sure the wheels will be straight before going an further. The bike is going to be really low. Now I'll be able to see whether the suspension or the frame bottoms out first. :shock:

I ordered a Y shaped shock from ChainReactionCycles.com after seeing a recommendation. It was a good price and free shipping from jolly old England, but all I have see from them for the last 5 days is the obligatory Paypal "yes we have your money" message. Let's hope it gets here soon.

-Warren.

PUGZCAT
recumbent enthusiast

Canada
240 Posts

Posted - 12/12/2011 : 03:07:06

When it's finished and painted up pretty send a picture to Bikerodnkustom, Jim Wilson would will like this one.

warren
human power expert

4230 Posts

Posted - 12/12/2011 : 06:24:36

Here's the cushy Planet Bike seat I bought from Gaerlen. Mounting it will be much easier than a recumbent seat. The tube I am holding will clamp to the tube behind it.

Here's the shock I purchased from ChainReactionCycles.com. After checking out how the shock will deflect I decided that a complex design as in the two drawings above is not needed.

After the obligatory grinding tweaking, eyeballing and rebrazing, the suspension is all straight now, or as near as I can tell. Now I am out of acetylene, refill Monday.

I'll be bending some 1/2" tubing to match the bend in the rear downtube...

-Warren.

PUGZCAT
recumbent enthusiast

Canada
240 Posts

Posted - 12/14/2011 : 03:33:55

An alternative to filling a tube with sand is filling it with water with a baggy an elastic at each end and freezing it, ice prevents tube crimping when bending.

warren
human power expert

4230 Posts

Posted - 12/14/2011 : 07:04:54

I have not had good luck with the "filling the tube" methods. I think that method would work for pipes, but not tubes. A wrinkle will form in the high stress area no matter how hard you pack the sand, and it's a huge mess. I think the ice method would have the same issue. The tubing roller I have works great.

I finished the seat bracket last night. Next, I need to make the front bracket for the shock to line things up before I build up the stays to attach to the suspension.

This bike is getting heavy. Good think I won't have to race it.

-Warren.

OpusthePoet
recumbent guru

USA
675 Posts

Posted - 12/14/2011 : 18:34:54

I have done the ice method for very sharp bends without wrinkles. You just don't have a lot of working time during a Texas summer. A Chicago winter? you have all day!

Opus

My gas is up to $0.99 a burrito, $5.99 for premium and I'm only getting 10 miles to the regular burrito. Dang $0.99 burritos are smaller now.

Admin
Forum Admin

56 Posts

Posted - 12/18/2011 : 07:25:37

I finished seat mount bracket and made the front shock mount. By using the split tube clamp design it is fully adjustable. Also a nice shot of my nicely organized workbench. Hey, I'm using that stuff!

I have just enough 1.5" tubing left to build massive stays. These really would not need to be this big but I think it looks better than a smaller diameter tube. I'll use .5" tube to triangulate from the rear shock mount down to the lower stay.

Here's what I'm using for the shock bearing. The socket shoulder screw fits into the brass bearing which fits into a couple concentric tubes. I had to hand machine (file) a bit off the outside of the outer tube to allow it to fit in the shock properly.

Here's the bearing in the shock.

-Warren.

Speedbiker
human power supergeek

USA
1996 Posts

Posted - 12/18/2011 : 08:51:06

What's all that brass colored stuff? Old school...

warren
human power expert

4230 Posts

Posted - 12/19/2011 : 15:06:08

I now have a rolling chassis. Because I used such beefy chain stays I will not need a huge amount of triangulation in the rear subframe. The BMC hub motor fits nicely in the rear.

I need to do a bunch of tweaking, finish brazing the tacked joints, and cap the tube ends before working on the bottom bracket and handlebars.

-Warren.

Speedbiker
human power supergeek

USA
1996 Posts

Posted - 12/19/2011 : 18:13:48

Cool, man!

Larry Lem
human power supergeek

South Sandwich Islands
1971 Posts

Posted - 12/19/2011 : 19:24:43

It looks like a horse with the front part of the frame. (Insert whinny) I can't wait until Warren rides it.

Larry Lem

Runxner
recumbent enthusiast

Australia
327 Posts

Posted - 12/19/2011 : 23:14:04

Nice, will it have longer bars? Looks like quite a reach I'd probably categorize it it a Softtail.

Team Low-Life
Lowracer Test Pilot/Evangelist
Adelaide, Australia

warren
human power expert

4230 Posts

Posted - 12/20/2011 : 05:50:12

Yeah, it will have longer bars.

alevand
human power supergeek

USA
1646 Posts

Posted - 12/20/2011 : 08:56:06

tight ride

C:
Tony Levand

PoiterH
New Member

Australia
62 Posts

Posted - 12/20/2011 : 16:41:39

Just a video of a local ride including a Chopper.
http://www.youtube.com/watch?v=aufjh60fD8A&list=HL1324427916&feature=mh_lolz

Larry Lem
human power supergeek

South Sandwich Islands
1971 Posts

Posted - 12/20/2011 : 17:49:02

Terrific!
I'd thought of choppers (motorcycle-type) and cruiser bicycles, but not recumbent chopper bicycles.
I don't think Warren intends his bike to be a laid-back recumbent and is using a standard, fat saddle.

Gardner said he was inspired by some magazine with a name such as "Big Bike" when he started developing the Easy Racers, but again, these weren't as close to being choppers as this bike.

Larry Lem

antipathyincarnate
Starting Member

Australia
2 Posts

Posted - 12/20/2011 : 18:19:18

Bobbers are pretty cool as well. The recumbent side of things just works a bit better with the chopper because you can bring the handlebars back over the rider.

(the other) Don.

Fast Choppers

warren
human power expert

4230 Posts

Posted - 12/22/2011 : 12:16:52

I finished brazing the frame tubes, did some tweaking, etc. Also I added handlebars and the bottom bracket shell. It's beginning to look like a bike.

The handlebars are 7/8 X .058" 6061-T6 aluminum, and I bent them with a 3/4" conduit bender. This works nice as long as you want to make a 5" radius bend. The handlebars are very wide and long, but they are in a comfortable position. I'll use these until I actually get a chance to ride the bike. I may end up doing a remote steering as it would be much more compact and I wouldn't have to deal with the "tiller effect".

The suspension seems to work well. Bouncing on the seat both the front and rear suspension have a bit of bounce but not too much.

Time for more parts! I'm still waiting on spokes to lace the drum brake into the front wheel, and need to obtain a bottom bracket and about a mile of chain.

-Warren.

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