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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 12/18/2018 :  21:10:49  Show Profile  Reply with Quote
I wanted to check to see if my pencil design for dropouts and carbon fiber plate transition from the tubular chainstays matches my design, which I made in some software that's actually for making crummy 3d printed doo-dads.

Turns out, pasting a screenshot of the scanned sketch allows me to see that yup, things line up pretty well. The 3d design software just vectorized the image, I scaled it, placed it, and there it was. (Gotta use the tools you've got.)



--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 12/19/2018 :  06:43:00  Show Profile  Reply with Quote
Here's a better view of my drive side dropout design. If anyone sees any bone-headed mistakes or has improvements to suggest, please have at it. I probably won't get to finalizing and cutting these until after New Years.


--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 12/21/2018 :  14:31:56  Show Profile  Reply with Quote
This is turning out better than I thought it would. And I'm also glad to find out that the simplest way to do it is hacksaw & file.





--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 12/22/2018 :  09:58:14  Show Profile  Reply with Quote
As close to done as it'll be until I pair it with the other side for a final filing some time in January: https://www.crazyguyonabike.com/doc/page/?o=1mr&page_id=566832&v=1W

--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/01/2019 :  15:39:47  Show Profile  Reply with Quote
A bit more progress after a nice family vacation in cloudy London.

I got the brake-side dropout drilled, cut, tapped, and I also did the carbon fiber transition plates that will be feathered into the chainstay tubing. This is the 4+ mm plate I made here at home. The brake side disc tab holes were only off by about 1mm when I was through, which is better than I expected. Maybe less even. I only needed to do a little filing in each hole to get the screws to fit right into the brake adapter.

The dropout is super long because I made it Rohloff-ready. I'm not planning on putting a Rohloff on the kid's bike, but since I'm thinking of doing this bike (a bit bigger) x2 for the wife and me for a hopefully simpler travel 'bent, I figured I'd just make it Rohloff ready so I can just swap the Rohloff's from the expedition bikes into these and save myself some wheel building. (But not much money since extra Rohloff shifters and clickboxes cost as much as a whole damn drive train).



A couple 6mm screws right into the 1/4" aluminum tapped M6 seems plenty strong.





Looks like I'll be starting jigging up the bike and cutting main tubing this week. The transition of the stays to the main tube is going to be a little complex for this beginner, but I have some PVC pipe doing nothing that is almost exactly the same size as the CF tubing I'll be using, so I think I'll model up a dry run with that stuff so I can make the dumb mistakes on something that doesn't matter so much (or cost so dang much).

--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/03/2019 :  07:00:36  Show Profile  Reply with Quote
Tested out the rear brake side dropout with a rotor mounted to make sure things were in working order (or near enough) before I started building from that dropout. Fitting looks nearly perfect. (Better than the fitting to the post mounts on the Chinese special front fork, which will require some fiddling)



Unfortunately, the avids don't work with the centerlock rotors I bought for a different reason. The tab from the brake pad clip interferes with the center star/holder for the rotor.



It would be simple enough to grind that off, and this is a known problem (that didn't bubble up in my reading on the rotors, however, until I searched for it specifically). Most have dealt with it by just cutting off the inside tab. However, one rider noted that the larger star means this rotor is much stiffer and therefore doesn't flex inward as a regular rotor does when using a single-cam mechanical disc caliper like the BB7, meaning you're mostly using the single side pad for braking, which is suboptimal and leads to early pad wear, very uneven, on the outside.

Solutions include buying a cheaper, deore-level rotor that has a smaller star (no interference, rotor flexes fine) as I've got on another bike. But that adds a fairly incredible 30 grams of weight, for some reason. Another solution is buying a 6 bolt to centerlock adapter, about 30 grams and $20, plus a regular avid rotor, about $30, or an off-brand rotor cheaper, I guess. That setup would be more flexible in the future, since you could stick any 6-bolt on there you wanted, and there are a lot more of those to choose from. Final option is saving these BB7s for an upcoming project and putting TRP Spykes on. About $65 per wheel, but dual-cam and reportedly a lot easier to set up than the Avids, though I've got BB7s figured out and it's nice to have the same brake on every bike in the garage...


--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/06/2019 :  10:17:42  Show Profile  Reply with Quote
After a short detour into spherical vs. cartesian coordinate systems, for which I am woefully unsuited, I managed to get what I thought were good paper templates to wrap and cut the coping on the chainstay tubes where they meet the main tube.

(Briefly put, the online program I'm using for making the tempates requires elevation and azimuth entries in degrees, and the program I use to design the bike uses straight degree measurements in x,y,z axis, so I had to back into my 24-degree chainstay interior angle by eyeballing it in the app.

I didn't want to leave this process to eyeballing because CF tubes are expensive, so I treated my ignorance a bit and found a good way to quickly translate those elevation and azimuth values into XYZ values, then pop them into another online calculator to get the interior angle. Turned out my eyeballed 24 degree angle was actually 24.4, so maybe eyeballing isn't so bad. Feel better having checked it though.

After getting the paper templates, I didn't want my first try to be on those pricey carbon fiber tubes either, so I spent $1.90 on a short piece of 27mm OD test material, trade name 3/4" PVC, and cut that with a disc, then rotating drum to get it right to the curves.

Seems to work about perfectly:







Plenty of clearance for a 40mm tire and fender. Tire should end up further back in build, so I think a 47 + fender will go, which would be perfect. Bike will probably run 40s all the time anyway.







--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/13/2019 :  16:01:32  Show Profile  Reply with Quote
Snow day here (for a couple days, probably) so after checking things a dozen times, I figured it was time to start putting on the chainstays. Turned out pretty well so far, within mm and fractions of a degree of my plans, which is good since the miter patterns were sort of freeballing it, and the tube-to-flat carbon fiber transition was completely by hand. I just started rubbing it on sandpaper, which was good because the slow progress let me check and see how things were doing, and it also yielded me a bunch of carbon black dust for coloring my fairing paste in the future. (recycle!)







I'll probably need to have it tacked for a week while I obsessively check the alignment and centering. Looks like I can pretty easily add the ability to route the derailer cable internally. Just need to keep some cable housing inside a straw when I paste up the far end on the drive side. Main tube, I'd just need a small hole inside the spot where the mitered chainstay attaches.

Same technique won't work for the brake side since on the far end, it would put the cable too low to make a good turn into the brake. I suppose I could put a hole in the chainstay further up. I'll decide that after I see how many layers of CF I've got at that juncture. I don't like holes in tubes unless they're super reinforced.


--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/14/2019 :  16:07:18  Show Profile  Reply with Quote
Finally satisfied with my setup. Sure took a lot of tweaking to get the jig as close to straight and square as possible. Half a degree here or there adds up to problems quickly! Measure 2 dozen times, glue once, I always say.



There's a little more room in the back than I thought. I was trying get get 185mm axle to the back of the main tube. Ended up with 190mm or so.

***Edit: Checking my 3D model and measuring it, I get 188mm axle to main tube, so I guess I did what I was supposed to.***

That means I've got plenty of room for a fat tire and a fender. I'll bond an aluminum nut into the lower part of circle at the boom before I close it up so I've got a good spot to anchor the front of the fender.

Weight of this chunk is 525 grams. A bunch of the CF plate will be trimmed off to run a smoother profile to the tube. I was thinking of drilling and filing out some of the vast expanses of aluminum on those dropouts to lighten things up, then I found a small chunk of scrap aluminum on the workbench, about the size of what I figure I could easily remove from the brake-side dropout under the brake tabs. So, I weighed it. SIX grams. Not sure it's worth it. If I cut the Rohloff tabs off that dropout and cut out some windows, I could maybe take 24 g off the thing.

I drilled a hole in the main tube under the right stay to run the derailleur cable. Of course I didn't make it big enough. It's not far in, so I'll worry it open a little more and get the cable housing run through, sleeved in a drinking straw, before I close up the ends.





I'll try to lay down an initial thin layer of CF fabric tonight, then smooth the joins with bubbles 'n' epoxy, then lay up the heavier layers. I'll be doing it in several stages, first the main tube to get those held on, then trim and wrap the ends with the plates, then back to the main tube. I'm hoping not to knock anything loose with the flimsy glue just holding. I'll lay up the initial layers in the jig to avoid wrecking things, except for dripping epoxy all over the basement of course.

--SpiderMonkey

Edited by - SpiderMonkey on 01/14/2019 16:19:54
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strayray
Warren

USA
10 Posts

Posted - 01/16/2019 :  04:58:23  Show Profile  Reply with Quote
SpideMonkey, this is a great series of posts! Thanks.
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/16/2019 :  08:49:08  Show Profile  Reply with Quote
quote:
Originally posted by strayray

SpideMonkey, this is a great series of posts! Thanks.



Glad you enjoy them. For the long version, don't forget to consult my CrazyGuy article. ;)

So, yesterday, I did 2 things. I contoured the chainstay transitions at the plates, and I did a little more work to try to make the internal cable housing run work on the drive side. I won't bore you with a description of the latter (it's here: https://www.crazyguyonabike.com/doc/page/?o=1mr&page_id=568382&v=f).

I'll just update with the hope that I did the right thing on this part of the build.



As I considered the layup to wrap those chainstay tubes to the plates, I didn't like the idea of any 90-degree turn in the wrap. I figure the plate is already far stiffer than it needs to be at that point (much stiffer than the tube) and after I wrap them both up, they'll be really stiff. So, I figured my priority should be on getting a good, lasting bond, and I should try to keep my fibers curving gently. Thus, the big trim.

This will also mean less filler and fewer stages in bonding those plates to the tubes. I don't like the way it looks right now, but I'm making sausages I guess. Delicious, pedallable sausage. The transition will be bulked-up by the wrap, and then I'll trim down the plates and the dropouts to match the contours a little better. I think I'm going to lose enough material to offset everything I'll be adding with the joins, or close to it. It would be pretty cool for this 1/3 of the frame to end up weighing less after joins are done than it did when things were just tacked on.

--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/19/2019 :  10:45:35  Show Profile  Reply with Quote
I was pretty nervous about the next stage, attaching the chainstays, since that's sort of an important bit. I already have 2-3 layers as a preliminary hold on the main tube chainstays (to keep me from wrecking them as I worked on smoothing, etc.) I filleted the connection to the main tubes like so:



There are a couple carbon fiber chips bonded under the putty there to give the transition off the end of the tubes.



I'll be doing wraps here with 90-45 alteration. I cut some 3k fabric I have into strips at a 45 degree angle to give me options.

I didn't lay those up today. At least not yet. I did the plate connections. I decided to use my brain (such as it is) to test how the wrapping would go, with fabric scraps from my sewing pile.



I figured 4-5 layers of 3k, 6oz plain weave in the main join area from this wrap, plus another 3 or so from a preliminary wrap with 45 degree 3k plain weave tape I cut. I figured I'd top it off with a layer of 8 oz braided sleeve, but by the time I had the wraps on, it was getting unweildy, and tighter wrapping than with the fabric scrap meant I had between 7-9 layers where it mattered. I think that'll be enough, and if it's not, I'll add a sleeve layer later.



The tape for each side weighed in around 18 grams, so I mixed 12 grams of epoxy for the first run. I thought I was going to run out at the end, but it looked like I did ok. I did my preliminary electrical-tape-inside-out wrap and the epoxy was oozing out already, so I knew I had enough. I wound from front to back, let the tape hang there, and perforated it. Epoxy started weeping out in decent amounts. I wiped the first ooze with a paper towl, then used my patented bleeder cloth (folded paper towel) for a light wrap, followed by another tight layer of electrical tape the other way. A couple chunks of foam for concavities / tighter corners at the end.

Did one side at a time. I'm glad I spent a lot of time perfecting my lousy methods on stuff like steering. Made it easier for me to be confident I've got a good connection here with one go.

I checked them after half an hour, prodding for bubbles where there might be an epoxy well from insufficient local pressure. Found what seemed like a couple, so I perforated and wrapped with a few winds of green cling wrap. I immediately evacuated a couple nice blobs of epoxy from those spots, so I'm glad I checked. Excited to see how it turns out.

The chainstay tubes will be pretty effectively double-butted, with wall thicknesses at the ends of probably about 2.5mm - 3mm, and the original 1.5mm wall thickness only in the 70mm or so in the middle of the tubes.

Even before this bond, I gave them a squeeze to compare to the old aluminum KHS frame I've got hanging on the wall. The KHS is a complete noodle by comparison. These are going to be stiff chainstays.

--SpiderMonkey

Edited by - SpiderMonkey on 01/19/2019 10:49:23
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/19/2019 :  13:58:06  Show Profile  Reply with Quote
Well the wife had to run errands so she took the dance class shift, meaning I had more time, so I put CF fabric on the main tube/chainstay attachments. I took out 10 slices of 2-2/5" wide 6 oz, 3k plain weave, half of them cut at 45 degree angle, each long enough to wrap the main tube + stays with some overlap, or none depending on where they ended up. I ended up using 3-4 extra strips of narrower stuff to cover a few seams. This was the first time I decided to try wetting them all out on a clean sheet of waxed paper then picking them up, instead of trying to wrestle the dry fabric around the part and mash it down/wet at the same time with a brush. Yikes, only about 100x easier, with a 90% reduction in loose strands flying off to annoy me. I don't know what took me so long to get that through my head. I guess I thought wetting them first would increase the odds they shed fibers when I picked them up, but it was less fiber shed, and wetted CF fabric forms so nicely, right away, and sticks well.

So, a dozen or more plies, not all overlapping in the same spots, of course, so probably about 7-10 plies coverge along the area of the stays/tube themselves, on top of the 2 plies already there. I'm hoping that will do the trick.

I spent a long time laying it up, but I still got good weeping through the tape I wrapped on the main tube and perforated. When I got to the parts with bulbous curves, I switched up my compression technique. I stuck some squares of perforated release film on the areas (backward electrical tape is handy for that, since it's already there) and I formed it as well as I could. Then, I wrapped it in some closed-cell packing foam, 1/4" thick stuff, and then I placed little sausages about 3/4" in diameter rolled of the same stuff along the concave-ish spots where I want to make sure I get pressure to press in the CF.I gave that a few winds of cling wrap, then pulled out the big foam, gave that many winds of cling wrap.



I thought I was done, but I could see I wasn't getting as much compression down the middle of the main tube toward the end, so I fashioned a couple levers from a cardboard box, wrapped one end, compressed the other, and not the whole thing is baking again on top of the basement heating ducts. It's going to be quite a reveal tomorrow.





I may do another quick layer to run a few plies from the inside of the rear main tube out and around the chainstays. I'll finish the layup ends here, and at the dropout ends, with a few winds of tow. I find that a perpendicular wind at the end of fabric reinforcement on a tube makes a nicer-looking transition than just a bunch of stray, funky weave ends sanded flat.


--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/19/2019 :  18:26:12  Show Profile  Reply with Quote
I was excited to peel the rear stays but figured I should wait until tomorrow. Then I remembered how tough it is to peel the paper towel "bleeder" when its saturated and fully cured. I found a leaky spot and the epoxy wasn't tacky to my fingernail anymore (just rubbery) so I peeled them. They look pretty good to me. The tubing that was 25mm is now 28mm, so I think I've achieved overkill. That's good, because they're a bit lumpy and I'd like to sand them flat, and I've got the leeway to do it.



The fabric pulled down and covered the white fillets at the ends nicely. I may not have to do much finishing work on that end at all.



There was a lot of epoxy ooze out from the tape. The composite looks pretty compact.



--SpiderMonkey
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Terry
New Member

Canada
58 Posts

Posted - 01/20/2019 :  09:58:55  Show Profile  Reply with Quote
You are making great progress . Even though ,at times ,a bit overkill!
If I could make one suggestion . When wetting out the cloth try doing it on the plastic sheet as you have done .Then. Put another similar sheet over top. Use a squeegee over the top sheet to get rid of excess epoxy. Now cut your pieces out. Easy to handle with the plastic on both sides. Peel one side off ,lay it on and gradually remove the other side. I hope this helps. I enjoy watching your project come to life.
Terry
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Balor
recumbent guru

Russia
704 Posts

Posted - 01/20/2019 :  10:11:18  Show Profile  Reply with Quote
quote:
Originally posted by Terry

You are making great progress . Even though ,at times ,a bit overkill!
If I could make one suggestion . When wetting out the cloth try doing it on the plastic sheet as you have done .Then. Put another similar sheet over top. Use a squeegee over the top sheet to get rid of excess epoxy. Now cut your pieces out. Easy to handle with the plastic on both sides. Peel one side off ,lay it on and gradually remove the other side. I hope this helps. I enjoy watching your project come to life.
Terry



In fact, I thought doing something like that with vacuum infusion. This way you can, in theory, quickly and reliably wet out multiple layers of cloth and even integrate core materials, but without need for very complex molds.
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/20/2019 :  12:57:34  Show Profile  Reply with Quote
That's a good idea, Terry. I will give it a try on the next layup. This one I was kind of cheating toward that by only wetting the fabric strips down the middle, with a stippling action, since I knew there was plenty of epoxy on the work piece. When I pushed it on and smoothed it with my fingers, it wetted easily, and pressing hard didn't show too much.

Usually, I get so much pressure with my double-wrapping that I don't have much worry about excess epoxy, but this time, my release film betrayed me a little. It's perforated, but not enough to reliably evacuate epoxy not under vacuum. There was enough pressure to push most of it out through wrinkles and evacuate the build layer. I found some good puddles, and the wrinkle lines, upon buffing, were just excess epoxy. After sanding, it appears pretty dense. I've gained only a net 50 grams or so with all the layers and epoxy (taking some material away from other spots during trimming) so I'm still in good shape I think.










I cleaned up the pieces this morning and mounted disc brake, derailleur, etc. to make sure everything was working as intended. Good clearances for all (I bought some TRP spykes so I could stick with the lighter shimano rotors. I save a good few ounces between the spykes and the higher-end rotors. I'll put the heavier Avids and Deore rotors on my version of this later...)

With a little sanding, I'm at this point. I can't decide if I want to sand the lumper rear stays flatter and smooth or not. Leaning toward not, since I'd rather have the material there.





I need to do another small layer on the stays, from the inside of the main tube to the inside of the stays, to cover the fillet there and reinforce. Then, I'll bond on an m5 nut of some kind for fender retention, then stick on a plate to seal the end (leaving a hole for the brake cable housing) and bond that on.

I've got my derailleur cable housing run working very reliably from the end of the chainstay, so long as a long zip tie is taped to the front end of the cable housing and slid in with the bent angle bit facing toward the inside, it feeds the cable housing in every time. I wanted to make sure that was the case before finalizing the rear end.

--SpiderMonkey

Edited by - SpiderMonkey on 01/20/2019 13:03:42
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/22/2019 :  08:36:53  Show Profile  Reply with Quote
I knew the lumpy chainstays would bug me forever if I didn't make an attempt to better them. So, I sanded off most of the high spots, filled a couple low spots with short winds of straight 12k tow, and added a single layer of 6 oz 3k. Came out looking a TON better.



More doodadery. I put some M5 nuts onto the fork to hold a fender. They're so stout I think you could mount a large bottle on them with no problem.



I decided to try to make a 3-pack of adjustable/removable seat clamps for the frame. To start, I needed some stout CF tube about 52mm ID, so I wrapped paper and plastic around a length of PVC until I got it that size. Prior to that, I slotted the PVC and shimmed it open about 3mm. The shims can be easily knocked out and then the pipe clamped to hopefully spring free the outer CF tube.

I wrapped the tube with many winds of 12k CF, one layer of 45 degree atop another at 0/90, so it's alternating with each wind. Interior and exterior in 3k for better surface.

I had tested using heat and shrink door/window seal to squeeze this, and it seemed sound, but when I put it on after layup, the power was pathetic. Good old green cling wrap took care of business.



BUT

I had overdoped the CF so much that the bleeder became saturated pretty quickly, so I poked holes in the cling and got a decent amount of push-out there too. The problem now is that I slept through the soft phase of the cure, and now my carbon fiber tube is entombed under a few MM of rock-hard bleeder. Some careful dremel work will need to be done this afternoon to avoid embarrassment.




--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/22/2019 :  19:25:13  Show Profile  Reply with Quote
Well, that's one way to make the world's ugliest carbon fiber tube.



So many errors, no good way to keep things tight during rolling, shouldn't use breather, too much CF cloth, etc. etc.

That said, it was an experiment using the last 1/3 of a roll of cheap CF, so maybe only $5-$8 and 2 hours down the drain. But I think this tube will actually work for the purpose I wanted to try building it -- making seat bracket parts. It's super thick, 3.5mm and more, and it'll be cut in half where the biggest wrinkles are anyway.

Some days the bear eats you. My layup to tweak front fork rotor clearance was also a fail, so I just cemented half a washer in the dropout to provide the spacing. I wanted CF to avoid rust potential, but quick and easy is quick and easy.

At least I didn't screw up the chainstay finish.


--SpiderMonkey
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warren
human power expert

USA
6454 Posts

Posted - 01/23/2019 :  08:31:10  Show Profile  Visit warren's Homepage  Reply with Quote
Several years ago I had good luck finding CF golf clubs at resale shops for a couple bucks each. The CF shafts made great seat stays.
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/23/2019 :  15:30:46  Show Profile  Reply with Quote
I remember that. I've got some 12 and 14mm carbon fiber tubing, china special, that has made good telescoping seat stays for me.

This is a 52mm ID tube for making the seat clamp around the 50mm main tube. My other option is to close up the base I guess and make it a carbon fiber Viking drinking horn.

--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/26/2019 :  12:36:03  Show Profile  Reply with Quote
Nervous today. I cut the boom to the size indicated in my plans (25cm) so that I could use the other 25cm for the ferrule for my plan to make the bike separable. I should only need 20cm of the tube for that if I make the overlap in each side of the main tube 2x the diameter of that tube, 5cm.

Next job, sand off all the nice glossy finish on that 45mm tube to prepare it to be thickened up. The inner diameter of my main tubes is 46mm, so I've got to put about half a mm all around this thing. I used some 9oz sleeve I've got, 3 layers. When I put on one layer and stuck my caliper on it, the 45mm tube was now 45.33-ish mm. I figured it would stay about that thick if I got it doped and squeezed properly, so I wet out the fabric and wrapped it up tight. Hopefully it won't come out too lumpy. I used cling wrap over release film and punched it with a long needle before putting on a layer of paper towel "bleeder" and more cling wrap and more needle pokes. The cling wrap allows me to get a much smoother, wider-surface press than using tape. Hopefully, it'll come right in around 45.99mm in diameter, and I'll just need to do a light sanding to get it to fit into the main tubes.

--SpiderMonkey
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/26/2019 :  12:40:18  Show Profile  Reply with Quote
I also did an experiment with some paint, a torn-tape fade color scheme, and covering it all with water-based spar urethane.



The kiddo loves the look, as does the wife. I'm OK with it. I'm trying to get a blend of showing the fun CF work as well as some bright color for visibility. I like the irregularity of this look, because it means I don't have to fail at trying to get perfect striping lines, and if it scuffs or something, it'd be hard to tell. It'll even hide brush lines pretty well, which seem to be prevalent with this fast-drying urethane.

--SpiderMonkey
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Jeroen s
Starting Member

Netherlands
13 Posts

Posted - 01/26/2019 :  13:54:04  Show Profile  Reply with Quote
Man i'd wish i found a tread like this when i build my first carbon bike. Clear explanation, nice pictures. I can understand every step u take. Love the build in wingnut trick.


This promises to be a great bike!
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SpiderMonkey
recumbent guru

USA
528 Posts

Posted - 01/26/2019 :  14:17:30  Show Profile  Reply with Quote
Assuming you saw the lengthier (gawdawfullengthier) explanation here to get the wingnut info? http://www.crazyguyonabike.com/doc/21502

I *hope* this turns out to be a good bike. I get super nervous every time I need to cut a fancy CF tube. I'm still leery of the plan to make it separable just in front of the seat, but I'm moving forward on that since it'll be a great incentive to get the bike into a suitcase and easily get the whole family out for tours in places like Italy.

I'll post the results of the ferrule bulk-up later this weekend. That's curing in my fancy resin autoclave (downstairs heating duct).


--SpiderMonkey
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