(MBBO#05 Class 2) Flashback GT - Done!

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All good concerns about the welding TJ. I'm a still 'novice' welder, using fluxcore, but I was welding some joints yesterday, and man, what improvement over when I first started out last spring. you using mig?

I now get the penetration I want, and know the settings by feel now , so I no longer worry about poor or weak joints...but , they still aren't real 'pretty' without a lot of sanding and filing, ya know?

Your welds actually are looking great with the finishing you did. I don't know maybe just a little hand sanding with fine paper may be all you need..but I agree, taking them down 'too far' it does weaken the joint. Globbing on more weld- Ive done that, it just creates more work that isn't 'fun' work. lol It's sortof like getting a decent smooth bondo joint, and then starting over with another heap of bondo.

I too would be leary of adding more heat...it's bound to pull something out of alignment..especially on all of those little 'bridge' joints on that beautiful frame.

I like what PhilTmonx said above about the aluminum filler...I was going to try that on some bars that I welded together, but decided to just let the bars go a little crusty rusty on that build.

I saw one post of someone smoothing out JB weld with some water and his finger..looked to make a super smooth joint...and you wouldn't have to go real thick...Maybe try a little clear on just one of your sanded joints..clear over JB weld, and clear on aluminum putty on a joint underneath or on the bottom somewhere not that visible see what looks best...

I hear you, it's probably pretty tempting to paint it...but that is just such a sweepingly beautiful frame..I know my mind can't picture it anything other than bare steel either....
again...:thumbsup::thumbsup:

franco

I know exactly what you're saying about the welds not looking "pretty" without some sanding and filing. Thanks for the compliment on finishing off the welds but, there's lots of room for improvement in my opinion.

I'm using a MIG welder with an argon / carbon gas mix. I've used fluxcore on past projects. Especially for areas where I was welding together some thicker pieces. The difference between using gas for shielding verses fluxcore is pretty dramatic in the way the welds look. I've been able to get a far better looking weld using gas.

Once there's no deadline and, before finishing off this frame, I think I'll run a few tests. Weld up a few samples and smooth the connections with solder, jbweld and aluminum filler for a direct comparison. Will give me a solid understanding of what it's like to work with each and what the final results look like.
 
Still picking away at the build. Here's a shot of the top and bottom seat pans.

seatPans.jpg


The bottom pan will receive some additional attention later. I had a nice smooth surface along the bottom at one point. That was before deciding I wanted to thin up the profile of the back of the seat. The fill piece took the brunt of the hammering needed to relax the seat back curve. I'll eventually cover it over with another piece. But, this did open the opportunity to try some plumbing solder as suggested by @GuitarlCarl. I ended up with mixed results but the process shows potential.

seatPanSmooth.jpg


seatPanSmoothSand.jpg


Seat mount points added to the frame.

seatMountPoints.jpg


Pair of forks cut with a pipe cutter and welded into one.

fork01.jpg


fork02.jpg


fork03.jpg


fork04.jpg


The latest wheels before cleaning and re-grease.

wheels.jpg
 

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Ridiculously cool. Hope this ride is successfully completed and ridden. I'd buy one!

furyus

PS: The original wheelset contrasts with the frame better in my humblest.

PPS: Dude. Marsha.
 
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The aluminum filler is "for" body filler for aluminum. I've heard people claim can use under powder coat, I had less than awsome results... But it is body filler, not really clear on why reg filler isn't recommended on aluminum, (been almost 20 years paint fumes, but did an Austin and was suggested) but it's a metallic grey, especially under clear.
Unlike filler w colored cream hardener it comes with white so it doesn't throw color in the mix.
You can add some fiberglass resin or "filler honey" same stuff, but really don't need add mutch it really goes far, it helps flow out but the more reason the harder to sand. I'm talking add maybe twice the amount you would hardener, it'll perform similar for sanding still...
 
Ridiculously cool. Hope this ride is successfully completed and ridden. I'd buy one!

furyus

PS: The original wheelset contrasts with the frame better in my humblest.

PPS: Dude. Marsha.

Thanks. Totally agree on the wheels. I even tried to design the "twin" connectors for the curved back frame pieces to echo the recesses on the wheel sides. If the wheels were coaster brakes or, I had another week to whiten the wheels and sort out the brake posts, cabling and levers they would so be on there. They'll find their way back eventually.

"all I ever hear is Marsha, Marsha, Marsha!"
 
The aluminum filler is "for" body filler for aluminum. I've heard people claim can use under powder coat, I had less than awsome results... But it is body filler, not really clear on why reg filler isn't recommended on aluminum, (been almost 20 years paint fumes, but did an Austin and was suggested) but it's a metallic grey, especially under clear.
Unlike filler w colored cream hardener it comes with white so it doesn't throw color in the mix.
You can add some fiberglass resin or "filler honey" same stuff, but really don't need add mutch it really goes far, it helps flow out but the more reason the harder to sand. I'm talking add maybe twice the amount you would hardener, it'll perform similar for sanding still...

The images I've been able to hunt down so far look like aluminum filler would be a great alternative.
 
I started the seat recover by glueing 1/4" dense foam to the seat pan with spray adhesive. With the final vinyl streatched over the foam the shape was too rounded. I ended up removing as much of the foam as possible, adding a backing / thicker layer of yellow vinyl, and then the final brown vinyl covering. Not a lot of cushion but the final shape was exactly what I was after.

assembledSeatCover.jpg


Last bit of fabrication, the rear reflector bracket.

reflector.jpg


refectorMounted.jpg


Cleaning and polishing pieces and parts.

cleanAndPolish.jpg


No images but, filing down the weld high spots on the frame is underway!
 

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