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rickmantoo
recumbent enthusiast

USA
274 Posts

Posted - 12/05/2015 :  18:14:35  Show Profile  Reply with Quote
Warren
I should be able to cut the profile needed on the inside of the head tube for you on my lathe if you like.

Rick
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PoiterH
New Member

Australia
65 Posts

Posted - 12/05/2015 :  18:30:34  Show Profile  Visit PoiterH's Homepage  Reply with Quote
You could keep the crown and upper blades intact and just dogleg out the lower parts to get the 135mm clearance. Bit easier and maybe stronger.
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Jackrabbit Jimmy
recumbent enthusiast

Canada
290 Posts

Posted - 12/06/2015 :  06:03:44  Show Profile  Reply with Quote
[quote]Originally posted by warren



It's not going to be easy to build 1-1/8" internal bearing CF head tube. Internal bearing head tubes have a beveled ledge inside the tube, and that's a hard thing to find. I ordered some CF tubing from China to at least give me a head start.

Warren, it sounds like you will be building your headtube in a similar method to what I used on my weight weenie bike. I built two tubes that nested in each other. I tapered the edge of the smaller diameter tube to the 45 degrees I needed for the bearing cartridge seat and cut the length down to about 8 mm. I bonded one of these pieces at either end of the headtube at the depth I needed.

What headset are you using? I used the FSA 23CC integrated headset which may be discontinued. It is fairly light at 63 grams.



Jackrabbit Jimmy
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warren
human power expert

USA
6050 Posts

Posted - 12/06/2015 :  06:10:01  Show Profile  Visit warren's Homepage  Reply with Quote
Pete, thanks, I think that is a good plan. Garrie sent me a pic of the Toxy FWD fork, I think that will be easier than clay mold.
Rick, thanks! Remember the fiberglass over foam lowracer you and Bill built? If only we had carbon fiber back then...
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rickmantoo
recumbent enthusiast

USA
274 Posts

Posted - 12/06/2015 :  08:33:23  Show Profile  Reply with Quote
Warren
His I do remember that bike, I have pictures some place.

Rick
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warren
human power expert

USA
6050 Posts

Posted - 12/06/2015 :  08:49:26  Show Profile  Visit warren's Homepage  Reply with Quote
Here's the fork with the clay on it, since removed... I will mount the fork in a jig and then slice and dice it.



These are the specs for a CF headtube that will accept the low profile internal bearings.



Jim - I'll try to use the "Speedmax" headset left over from the actionbent. There's not much to them so not much weight saving to go for the zooty model.
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alevand
human power expert

USA
2876 Posts

Posted - 12/06/2015 :  11:52:55  Show Profile  Visit alevand's Homepage  Reply with Quote
I like that, Warren, is the seat integral? Are you planning to vacuum bag it? How many layers of carbon does it need? I want to see how the head tube, BB and dropouts are attached. How would you put canti-studs on a CF tube?

quote:







C:
Tony Levand
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warren
human power expert

USA
6050 Posts

Posted - 12/06/2015 :  14:38:15  Show Profile  Visit warren's Homepage  Reply with Quote
Tony - yes the seat is integral, so I have to make sure that the bike really fits me. That shouldn't be too hard as the layout is exactly the same as the dual 700 steel framed bike I was racing this year.

No Canti-studs I am using a caliper brake.

I'm planning on laying up a couple base layers over the foam then removing as much foam as I can get to before adding a couple more layers. What's the least toxic chemical that I could use to dissolve the polystyrene foam? The final layers will be bagged. Not sure about the initial layers, I don't want to crush or warp the foam. I may need to add more in certain areas, not sure yet.

I certainly don't have all the answers and will be figuring it out as I go...
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alevand
human power expert

USA
2876 Posts

Posted - 12/06/2015 :  16:54:50  Show Profile  Visit alevand's Homepage  Reply with Quote
Gasoline, maybe paint thinner, naphtha.

C:
Tony Levand
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alevand
human power expert

USA
2876 Posts

Posted - 12/07/2015 :  03:44:59  Show Profile  Visit alevand's Homepage  Reply with Quote
I had a thought, if a wire is embedded from tip to end, say welding wire, and after the part is laid up and cured, put a current on the wire. It will melt a hole through the EPS. put a funnel at one and a catch at the other and pour through the solvent.

C:
Tony Levand

Edited by - alevand on 12/07/2015 03:45:44
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Garrie L Hill
human power supergeek

USA
1689 Posts

Posted - 12/07/2015 :  05:26:01  Show Profile  Reply with Quote
Warren;
The real question is; "Why dissolve the foam?" With the foam, the frame will be noticeably quieter. The frame will have marginally but measurably higher resistance to buckling. The dissolved foam, unless aggressively washed out, will just collapse into a thin and possibly gummy layer ( depending on the solvent used ). No weight will be saved if this happens.

Garrie "carbon based lifeform" Hill
HPRA Co-Dictator of the East
for pics of some of my time and money sucking projects
http://garriehill.winkflash.com/
and
http://s58.photobucket.com/albums/g277/cfbb/
and videos
http://vimeo.com/5513519


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alevand
human power expert

USA
2876 Posts

Posted - 12/07/2015 :  06:46:43  Show Profile  Visit alevand's Homepage  Reply with Quote
Not to mention spontaneous combustion. I remember seeing a picture of Warren's bike on fire once.


quote:
Originally posted by Garrie L Hill

Warren;
The real question is; "Why dissolve the foam?" With the foam, the frame will be noticeably quieter. The frame will have marginally but measurably higher resistance to buckling. The dissolved foam, unless aggressively washed out, will just collapse into a thin and possibly gummy layer ( depending on the solvent used ). No weight will be saved if this happens.

Garrie "carbon based lifeform" Hill
HPRA Co-Dictator of the East
for pics of some of my time and money sucking projects
http://garriehill.winkflash.com/
and
http://s58.photobucket.com/albums/g277/cfbb/
and videos
http://vimeo.com/5513519






C:
Tony Levand
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warren
human power expert

USA
6050 Posts

Posted - 12/07/2015 :  06:56:24  Show Profile  Visit warren's Homepage  Reply with Quote
Garrie - yes that is an option. The only issue is that I may be using other materials like plaster to do fillets and fill in dents. I'm thinking now that I will layup a left and right half then join them.
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alevand
human power expert

USA
2876 Posts

Posted - 12/07/2015 :  08:40:19  Show Profile  Visit alevand's Homepage  Reply with Quote
Plaster (dry wall compound) will wash out with water... after the EPS is dissolved, but yes it could be a gooey mess. A test will tell.

quote:
Originally posted by warren

Garrie - yes that is an option. The only issue is that I may be using other materials like plaster to do fillets and fill in dents. I'm thinking now that I will layup a left and right half then join them.



C:
Tony Levand

Edited by - alevand on 12/07/2015 08:41:24
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warren
human power expert

USA
6050 Posts

Posted - 12/07/2015 :  17:39:39  Show Profile  Visit warren's Homepage  Reply with Quote
Ok, so I won't be trying to dissolve any foam. Sounds gross...

Garrie made a cool mold to make a CF head tube for me. That will help a bunch.
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warren
human power expert

USA
6050 Posts

Posted - 12/08/2015 :  17:52:27  Show Profile  Visit warren's Homepage  Reply with Quote
Did the first rough pass at shaping the foam with the big file. Lots of blue foam dust everywhere. Fun.
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warren
human power expert

USA
6050 Posts

Posted - 12/12/2015 :  14:28:51  Show Profile  Visit warren's Homepage  Reply with Quote
Here's a drawing experiment to see how much more the forks would have to be expanded to get to 130mm. This looks like it will work ok. I will need to reinforce the chopped areas with many layers of CF. It will probably be overkill.



I spent many hours filing and sanding and adding bits here and there to get good filets. The fillets under the seat are very important to keep the airflow down there as clean as possible.

The seat and rear seat stays still need to be widened a bit so I am not near done. It's pretty well roughed in otherwise. Next I will fill in the rough areas with drywall compound and do a bunch more sanding.

The bike was laid out on the floor and propped up some wheels to idiot check the sizing. Looks good. The back wheel will slide up another couple inched forward when I finish the stays.




I had some discussion with Thom about fairing the drivetrain. I think this has merit and I can add that on later.

I located a titanium BB shell in my parts bin, I wasn't sure if it was aluminum or Ti, so I hit it with the grinder to check for sure. It shot off white sparks, which means Ti. Aluminum would not have any sparks. It's pretty thick so also not very lightweight. I may have to drill some holes or something to lighten it up.

Once the shape is decent the current plan is to first paint the foam with green mold release and then lay up 2 layers of CF over the bottom half of the bike. No vacuum bagging now, I will do that for the final layers after I have a solid structure, otherwise the pressure of the vacuum could warp the foam. I am doing an experiment now to see if the alcohol based green mold release will eat the foam.

Edited by - warren on 12/12/2015 14:31:21
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alevand
human power expert

USA
2876 Posts

Posted - 12/13/2015 :  05:57:41  Show Profile  Visit alevand's Homepage  Reply with Quote
Who needs 3D printing. looks cool, Warren. Did you glue in small pieces for the fillets? How did you manage the front brake?

C:
Tony Levand
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warren
human power expert

USA
6050 Posts

Posted - 12/13/2015 :  06:29:37  Show Profile  Visit warren's Homepage  Reply with Quote
I purchased a campy aero TT brake from niagara cycle, which looks the same as the TRP T925 but was about half the price.

Yes I glued in small pieces for the fillets, then sanded the concave shape with sandpaper wrapped around a spray paint lid.

One more day of rough shaping then I start with the wall compound.
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warren
human power expert

USA
6050 Posts

Posted - 12/13/2015 :  12:38:42  Show Profile  Visit warren's Homepage  Reply with Quote
More sanding foam, The seat was 3 sections of foam wide - 6 inches. I widened the seat by the shoulders to 10 inches and faired it into the seat stays. Started applying the drywall compound to fix some issues and fill cracks and rough areas. It will take a several days to dry. I hope it sticks. It's looking pretty sexy.
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warren
human power expert

USA
6050 Posts

Posted - 12/17/2015 :  17:37:56  Show Profile  Visit warren's Homepage  Reply with Quote
Here it is after the second coat and a bunch more sanding. This is probably the last coat before I coat it with mold release



Here it is from the back side. I'm pretty happy with how it is turning out.



The "Campagnolo Front Aero Brake Lateral Pull, For Time Trial/Triathlon Bikes" I ordered from amazon to use for a front brake did not look like the picture. I think the one they sent me was either a rear brake or it was meant to be mounted behind the fork. I had to terrorize it by drilling an extra hole to get it to work with my fork.. Par for the course in recumbent land.
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rando_couche
Starting Member

13 Posts

Posted - 12/18/2015 :  08:24:23  Show Profile  Reply with Quote
Warren - if you end up deciding that the steel frame needs a new home, I'd be interested in adopting.

SP
OC, OR
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shooky56
recumbent guru

USA
544 Posts

Posted - 12/18/2015 :  08:29:51  Show Profile  Reply with Quote
Warren that shape is beautiful! Hope it rides as fast as it looks!
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warren
human power expert

USA
6050 Posts

Posted - 12/18/2015 :  17:40:24  Show Profile  Visit warren's Homepage  Reply with Quote
Thanks Wayne.

Scott - how tall are you?
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alevand
human power expert

USA
2876 Posts

Posted - 12/19/2015 :  04:38:54  Show Profile  Visit alevand's Homepage  Reply with Quote
Himeros Cuda

:C
Tony Levand
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