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warren
human power expert

USA
6119 Posts

Posted - 12/19/2015 :  08:59:43  Show Profile  Visit warren's Homepage  Reply with Quote
Ha, I had to look that up Tony. Yes, I agree.
http://greekmythology.wikia.com/wiki/Himeros

I put a couple layers of green mold release on the bottom side of the form. Once I get it all coated I will use some spay adhesive sparingly to stick down a couple layers of CF on the bottom side. I need to build a foam box to put it in while its curing because it's about 40F out in the garage now. A light bulb in the box will keep it plenty warm.
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rando_couche
Starting Member

13 Posts

Posted - 12/19/2015 :  18:02:44  Show Profile  Reply with Quote
quote:
Originally posted by warren

Thanks Wayne.

Scott - how tall are you?



6'3", 37" inseam, 47" xseam.
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warren
human power expert

USA
6119 Posts

Posted - 12/20/2015 :  05:56:20  Show Profile  Visit warren's Homepage  Reply with Quote
You are all legs. I think you would fit.
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rickmantoo
recumbent enthusiast

USA
274 Posts

Posted - 12/20/2015 :  08:46:41  Show Profile  Reply with Quote
Warren
Why are you adding release agent on the foam? I would think one would want the carbon to stick to the foam.

Rick
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warren
human power expert

USA
6119 Posts

Posted - 12/20/2015 :  10:03:40  Show Profile  Visit warren's Homepage  Reply with Quote
Epoxy sticks to everything, including release agent, and I think release agent is lighter than epoxy. I have made a lot of parts that were composite over foam, and the epoxy seems to soak into the foam, making a part that is heavier than if you can somehow prevent it from soaking in. The mold release should prevent the epoxy from soaking into the foam. I am planning on removing the foam and wall compound from the main body of the frame, and most of the rear stays. I may leave it in the front section for added strength. With the mold realease I can chip out most of the foam and wall compound and then wash out the rest with water.

Apparently I have plenty of CF (thank you AA). I am thinking 2 layers of CF, remove foam, and insert brake housing, then vacuum bag the rest. Some experimentation will need to be done to determine how many layers in what area. I am wishing I had someplace warm and dedicated to do the lay ups.
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alevand
human power expert

USA
2940 Posts

Posted - 12/20/2015 :  13:40:26  Show Profile  Visit alevand's Homepage  Reply with Quote
Cure time doubles every 20 degrees F cooler.

C:
Tony Levand
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warren
human power expert

USA
6119 Posts

Posted - 12/20/2015 :  14:34:52  Show Profile  Visit warren's Homepage  Reply with Quote
Laid up one crappy layer of CF over the bottom of the form in my dark and cold garage. It's in the pink foam oven now, looks like about 70F in there.

I added some plastic wrap to hopefully stick down some of the CF that was sticking up and hopefully reduce the post cure cleanup and sanding.

.

I had to clean it up after it cured, but it turned out ok.

Looks like 1 layer of CF will be strong enough to vacuum bag over. Next step is to build and attach the CF rear dropouts, and cover the rest of the rear stays with a layer of CF.


Edited by - warren on 12/21/2015 14:31:37
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alast
Starting Member

New Zealand
21 Posts

Posted - 12/21/2015 :  14:39:25  Show Profile  Reply with Quote
Looks like a post-nuclear turkey carcass
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alevand
human power expert

USA
2940 Posts

Posted - 12/22/2015 :  08:35:09  Show Profile  Visit alevand's Homepage  Reply with Quote
Yum, my favorite. What do you do with the frayed edges, just sand them down wearing a mask?

C:
Tony Levand
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warren
human power expert

USA
6119 Posts

Posted - 12/22/2015 :  10:20:18  Show Profile  Visit warren's Homepage  Reply with Quote
Yes I cut and sanded the edges. I wear a mask any time I get near CF cloth or dust.
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warren
human power expert

USA
6119 Posts

Posted - 12/22/2015 :  18:19:02  Show Profile  Visit warren's Homepage  Reply with Quote
I cut out some CF dropouts for the rear of the bike. I have committed to FWD, so the dropouts are only 100MM wide. I put the bike in the frame jig, glued them to the foam stays, put the heat lamp on them and crossed my fingers hoping that it was really lined up properly.

Several hours later I removed the bike from the jig and tried it with a real wheel in the dropouts. Nope, it was off a bit. I accidentally broke off one of the foam stays but that turned out well and I was able to trim it down a bit at the break to bring make the wheel straight and re-glue it. Once it cures again I will re-check it to be sure it is true before I cover the rest of the rear stays in a layer of CF.

Edited by - warren on 12/22/2015 18:21:41
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Jeff Wills
human power supergeek

USA
1271 Posts

Posted - 12/22/2015 :  20:37:01  Show Profile  Reply with Quote
quote:
Originally posted by warren


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.






The more I look at that, the more I think of Rob English's Hachi:

http://rob.bikerevuk.com/mybikes/hachinew.html



__________________
Jeff Wills
All my bikes:
(Site nuked by Comcast. Will return soon.)
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alevand
human power expert

USA
2940 Posts

Posted - 12/23/2015 :  05:16:38  Show Profile  Visit alevand's Homepage  Reply with Quote
I guess the rider wouldn't get thigh burn because of the crank overlap. Looks like it has Warren's notch for the front brake.

C:
Tony Levand
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warren
human power expert

USA
6119 Posts

Posted - 12/28/2015 :  17:55:38  Show Profile  Visit warren's Homepage  Reply with Quote
The Garrie Hill CF head tube arrived and it's very light. I tested it with the bearings and fork and it all fits together well. Here it is with the internal head set that fits into it. Basically the head tube also serves as the cup portion of the headset.



I still need to sand down each end of the headtube until it is flush with the bearings. Garrie sent me some wet and dry sandpaper and noted that it's best to sand CF with wet sandpaper to eliminate the dust issue. Great idea.

This is the top and bottom bearing of the internal headset assembled with the races, cap, etc. It's tiny and lightweight and very low profile.



Warren


Edited by - warren on 12/28/2015 17:57:08
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warren
human power expert

USA
6119 Posts

Posted - 12/29/2015 :  10:45:12  Show Profile  Visit warren's Homepage  Reply with Quote
I was doing some drawing to try to get an idea for a graphics scheme for the new bike and discovered that a handlebar that is slightly curved to match the curve of the frame looks markedly better than a straight handlebar. Plus, it will be faster, right?
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Patrick Bateman
New Member

USA
69 Posts

Posted - 12/30/2015 :  14:52:50  Show Profile  Visit Patrick Bateman's Homepage  Reply with Quote
quote:
Originally posted by Jeff Wills

quote:
Originally posted by warren


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.






The more I look at that, the more I think of Rob English's Hachi:

http://rob.bikerevuk.com/mybikes/hachinew.html



__________________
Jeff Wills
All my bikes:
(Site nuked by Comcast. Will return soon.)



Jeff probably knows this already, but if anyone else is interested in having a recumbent built, Rob English builds custom bikes. He has some pics of his work on his facebook page. He's out of Eugene Oregon IIRC
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Patrick Bateman
New Member

USA
69 Posts

Posted - 12/30/2015 :  14:57:26  Show Profile  Visit Patrick Bateman's Homepage  Reply with Quote
quote:
Originally posted by warren

After a few revisions I think I have a 1X drawing that looks right. Next step is to cut some foam.

If I do FWD I will need to cut up my spiffy new CF fork to widen it 35mm. If I do RWD, the return chain will be just above the front dropout. I should be able to add a chain tube to keep it under control but it won't be optimal. Or maybe I should just run it under the front dropout? Decisions...



I've always had a really difficult time building bikes that go straight. It's really frustrating to invest a month building a bike, only to find that it's unstable because my build quality is shoddy.

There are some really affordable laser cutters on eBay nowadays. It would be interesting to draw a bike frame in a 3D program, then cut the pieces out of cardboard or foam on the laser cutter. I've had good luck with both foam and cardboard; a big chunk of my MBB FWD bike was made out of cardboard wrapped with fiberglass. IKEA was my inspiration; a great deal of their furniture is simply cardboard with a thin veneer of wood.

My laser cutter just arrived yesterday, I paid $400.
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warren
human power expert

USA
6119 Posts

Posted - 12/30/2015 :  16:12:17  Show Profile  Visit warren's Homepage  Reply with Quote
Building the bike so the wheels are straight and in line and everything is something I have difficulty with too. It's easier since I built a frame jig, but apparently my jig is not perfect. I build the bike in the jig and just tack on the dropouts, then add the wheel and measure and eyeball it again, that usually makes it close enough.

Good luck!
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Speedy
recumbent guru

USA
884 Posts

Posted - 12/30/2015 :  16:56:44  Show Profile  Reply with Quote
Any one off frame build will need to be aligned in some way.
It's a great idea to leave enough flexibility in the design for the alignment process.
Bolt on dropouts serve this purpose nicely. If the first set is wrong simply remove and make new.

BTW ... $400 for a laser cutter is a crazy screaming deal ... what did you get ?


quote:
Originally posted by Patrick Bateman

quote:
Originally posted by warren

After a few revisions I think I have a 1X drawing that looks right. Next step is to cut some foam.

If I do FWD I will need to cut up my spiffy new CF fork to widen it 35mm. If I do RWD, the return chain will be just above the front dropout. I should be able to add a chain tube to keep it under control but it won't be optimal. Or maybe I should just run it under the front dropout? Decisions...



I've always had a really difficult time building bikes that go straight. It's really frustrating to invest a month building a bike, only to find that it's unstable because my build quality is shoddy.

There are some really affordable laser cutters on eBay nowadays. It would be interesting to draw a bike frame in a 3D program, then cut the pieces out of cardboard or foam on the laser cutter. I've had good luck with both foam and cardboard; a big chunk of my MBB FWD bike was made out of cardboard wrapped with fiberglass. IKEA was my inspiration; a great deal of their furniture is simply cardboard with a thin veneer of wood.

My laser cutter just arrived yesterday, I paid $400.



Steve Delaire

http://molten3d.blogspot.com
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alevand
human power expert

USA
2940 Posts

Posted - 12/30/2015 :  18:21:52  Show Profile  Visit alevand's Homepage  Reply with Quote
I lineup the back wheel to the front and the front wheel to the back, then I use a level and put both in plumb, then check again, then tack it, then check again, then finish weld, then check again, then cut and re-weld if necessary. Then I cut the whole thing off and start over again. Still haven't gotten it right.

C:
Tony Levand
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warren
human power expert

USA
6119 Posts

Posted - 01/01/2016 :  10:54:50  Show Profile  Visit warren's Homepage  Reply with Quote
I added a layer of CF to the rear stays and down tube area yesterday, and this morning I used the belt sander to clean it up out on the driveway. I'm sure my neighbors were impressed with the racket on a cold New Years morning.

I found another great use for old inner tubes. They can be used to compress composite layups. I cut a slit in the tubes lengthwise and wrapped them around the downtube area. They are just stretchy enough to give decent compression. I did have to use the aforementioned belt sander to remove some artifacts after it cured.

Next step is bonding the head tube in the right place but the garage is too cold to work in now.
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alevand
human power expert

USA
2940 Posts

Posted - 01/01/2016 :  11:42:51  Show Profile  Visit alevand's Homepage  Reply with Quote
I was looking at filament winding videos on you-tube and one wound on shrink wrap layers to compress it.

C:
Tony Levand
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warren
human power expert

USA
6119 Posts

Posted - 01/02/2016 :  11:00:11  Show Profile  Visit warren's Homepage  Reply with Quote
Today the head tube was bonded into place with some PC11 epoxy. Things are lining up fairly well but it looks like I will need to tweak the rear dropouts just a bit.



Once that cures and I make sure its all straight I will be ready to add the front boom section.
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alevand
human power expert

USA
2940 Posts

Posted - 01/03/2016 :  06:03:13  Show Profile  Visit alevand's Homepage  Reply with Quote
It looks plenty stiff in the vertical plane. It looks like the forks are filament wound.

C:
Tony Levand

Edited by - alevand on 01/03/2016 06:07:01
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warren
human power expert

USA
6119 Posts

Posted - 01/03/2016 :  13:00:15  Show Profile  Visit warren's Homepage  Reply with Quote
I didn't have much PC-11, so there wasn't enough surface area to bond to and it didn't hold. I mixed up some epoxy and micro balloons today and bonded the head tube in well. After it cured it seems to be in the right place. Yay!

The boom tube was fitted into place. I taped the template to the side of the frame to ensure it was in the correct location, and that the crotch to BB distance was 34" as per the 1X drawing and the steel version of this bike. Apparently the head tube is a bit more upright than on the template, so I have about 1" of trail instead of 2". That should be ok.



Before I attach the boom tube I will need to cover it in a layer of CF.

Edited by - warren on 01/03/2016 13:02:51
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