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Duchess said:
Got a little done on the cowl. Now I need to form the cowl extension onto it without melting the reinforcements, drill and weld through. For the spot welds, I used countersunk bores on both sides and used a piece of wood underneath so that when I pushed the ABS weld rod through, it filled the countersink on the backside with the idea being that it would work like a rivet. Unfortunately, the heat gun is overkill and a blowdryer too weak to hit a good temp for the plastic, so ]pre-heating it without overdoing it (which I did a little, hence some waviness), then maneuvering the welder and getting the weld rod into place before it cooled too much was tough, so that's why I decided to go with countersinks. I also went over the weld ends with the welder to blend it further. To clean up all the ugliness, I'm going to take the scrap ABS bits and melt them in acetone to make a filler. I read that works, but I haven't tried that particular thing before. If it does work, I imagine it would be a lot better than epoxy or body filler since things don't like to stick to ABS. Plus, it's free. I have plastic welded a little with polycarbonate (really tough), polypropylene (fairly easy), and high density polyethylene (similar to PP), but I have never tried ABS before nor this filler technique. Car bumpers and kayaks are a lot easier than this was, but I'd still take it over PC.

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Very cool. My company does a lot of sonic and adaptive welding on various resin substrates for some of our customers. Heat staking for a certain electric car manufacturer, and lots of heat coupling of polypropylene tube for certain defense applications
 
Got new tires—literally new limited production Panaracers that just came out (They do several colors every year for only that year and I lucked out on this year's having this blue. USAAF bike has olive green ones from a few years back and I really like them. Guess I'll see how they hold up to an e-bike.)—and pedals. Tire color matches the grips pretty well. Could not find matching pedals in anything resembling a decent price, so I went with purple.

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Worked a little more on the back rest fairing. Getting the heat right is a learning curve and will require some remediation, anytime I make something new, I do stuff I've either never done at all or in a more limited manner. I need to find the right day to do this—too hot and it's TOO HOT to be running a heat gun and plastic welder, too cold to open the windows, like today, and it stinks and it can't be a healthy stink.

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Seam welded and "seems" really solid. Was able to fix much of the waviness around the corners by heating up the concave areas with the heat gun and rolling it flat across on a piece of scrap plywood using some leather to keep my hands from burning. Still need to sand and fair it. Also cut out the sea serpent torque arm.

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I'll see how it cures, but I'm really impressed so far with melting ABS plastic in acetone to create a body filler. I used scrap cut-offs and the ends of weld rods that were too short to use mixed in a glass jar. Sanded the base with 80-grit to give it some tooth before applying it with a metal scraper. I'll find out if I should have softened the base with acetone to start.

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Thanks for all the details. It's always cool to see new tricks and processes here on RRB. Looking good.
 
It works! No pic as I had to add some more filler, but melting ABS in acetone works really well. For thicker blobs of ABS goop, you might have to give it 24 hrs.

As a note, make sure you know it's ABS. I threw a couple small test pieces in that I wasn't sure if it was ABS or HDPE. It was the latter and it was messy getting those pieces out as they don't dissolve in acetone.
 
Really cool process going on here. Very creative and innovative approach.

InNovaTe oN~!
 
Migraine and a friend's kid's birthday party didn't completely stop me from getting something done. Closed cell cushion and leather for the back rest.

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MattiThundrrr said:
Migraine PLUS kid's party? Ouch. Perseverance Award!
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I actually got the migraine BEFORE the kid party, too. It was a mild one, though, otherwise I'd have been knocked down for a day. The gifts I got were hits, at least.
 
Just a couple more pits to fill to finish fairing the fairing. Also sewed up the backrest and painted it. First one I did came out better. Not sure where I went a little wrong on this one, but it's slightly baggy on one corner.

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Very cool. It seems to me that the rear cowling would look better if it was lowered a bit.
 
What's the difference in radius between a 26" fender and 700c tire? Here you are. I traced the outline box that will conceal a bunch of the wiring based on an old 26" fender and made sure to err on the side of leaving more material than I need since it's easier to remeasure and recut than put material back.

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kingfish254 said:
Very cool. It seems to me that the rear cowling would look better if it was lowered a bit.
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The whole back end might end up too high, but it's a matter of function. Not that I expect to put much weight on the backrest. My goal is to get the windshield and fairing top curves to look like they could be part of a continuous arc. The fairing will house a lot of the electronics for the bike—main switch, circuit breaker, 52/12V converter for the lights, those kinds of things. The white box is for my laptop. On each side will be old Dewalt tool cases as panniers for the battery packs (it's a large battery, so I'm splitting it between the sides for weight distribution). I'm probably going to try to keep them low for balance and since it will be easier to mount them rigidly, but if I think they'll be OK hanging directly under the rack, I think that will fill in that dead space above the tire. If I do that, I have some extending aluminum T slot braces that will extend from the rack to the rear triangle matching the angle of the seat post so that everything can be moved with any change in seat height. I'm using that stuff either way to keep the rack from rotating, but whether the panniers are fixed or move with it is TBD. Or a 36" rear wheel would fill that space and balance it out, too! (I'm not doing that because practicality is a harsh dictator, but I think it would be interesting.)
 
Any news on this cool build?
TicTocTicToc :D
 
I'll try to pick at it, but I'm definitely not going to finish. I have too much going on.
 

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