j57little's - Roper Rebuild - (Vintage Class)

j57little

Active Member
#82
Hey Paul, great to hear from you! I have a lot of work on this project so I appreciate any comments positive or not. By the way did you ever finish your Rupp? I'd love to see photos.
 

j57little

Active Member
#84
Finally got weather to paint. The color came out as desired, but the K2 clear coat had a tendency to fish eye. I think I can polish it out, but that adds just one more long step to the process.
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The high tech paint booth worked well -only a few gnats!

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Lots of small parts. Ropers were a heavy contraption - here's why...

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Pearl coat before clear coat

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Motor Mount - more weight!

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The pearl over yellow/orange worked.

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Lots of smoothing and polishing are needed, but overall it came out pretty good.

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I have the original type vinyl stripes for the fenders, but it would almost be a shame to apply them.

One last major paint step - the tank - maybe by Wednesday.
 
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#88
Sanding and buffing takes a lot of time. Most times it is faster to wet sand the clear smooth with 600 then spray on more clear.
Buffing small parts isn't fun...

Danford1
 
#89
I like the pearl in there. Nice, smooth job. I don't see any fisheye, and never experienced it with urethane clear. Something in the gun or air line? I shoot clear at flash over, usually 20 minutes later. Bah. No matter, you did a good job on this one, and I enjoy watching you derive enjoyment from it. Pearl looks good. :thumbsup:
 

j57little

Active Member
#90
Thanks Dave,
That's exactly my plan. Fortunately the small parts are OK - just the big, important parts need some smoothing and another coat. I'm just not sure why I got so many bubbles. I was using a different K2 clear. Spraying outside probably didn't help.
 
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j57little

Active Member
#92
Thanks Chipper. I am repainting some pieces this weekend.

Between bubbles and dropping the front fender the paint is taking way too long, but I think I found the source of the bubbles in the paint:

1) I did not let the pearl coat flash completely. The bubbles were the solvent trying to escape, and
2) I was too thick in a few places. Thick coats can dissolve the layers underneath.

I suspect Dave will probably concur with this assessment. We know what will happen when we try to rush and I just can't let time and weather force me to take short cuts. Mini bike restoration is like a pregnancy - it takes a certain amount of time. You can try to reduce it, but the results won't be good!

Fortunately the tank came out right. Photos coming soon.
 
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j57little

Active Member
#95
I'm down to the last few bits and pieces, but one item that always comes up for me is spacers. I suppose if you start with a bike that already has them you're ahead of the game, but the ones I had were completely rusted out and I also wanted to move from half-inch axles to five-eighths, so new spacers were required. Most places sell them in half or quarter-inch increments, so of course I needed a 1-15/16" and 7/8" spacers. Many of you have machining skills and equipment so it's no big deal, but for me I have to improvise. Keep in mind I always want safety to be first (it sometimes comes in no better than third), but this is a fairly simple and quick way to make my own spacers without putting life and limb at risk. I wrapped a drill bit with masking tape so that the spacer stock would friction fit onto the drill press. Then using a grinder and cut-off wheel I was able to quickly and safely cut my spacers to the exact length. Make sure to stop before you come to the drill bit! Sure, many have done this sort of cutting before, but for some of the new guys this might be the idea they needed.

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Smoothing on the sanding disk.

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and finally polished out with steel wool - make sure not to let it catch on the bit or it will go around and around!

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#96
LOL, yeah, I made my own spacers too. It isn't easy at all without the right saw. Your "lathe" looks familiar as well. Pat uses the same type as we do. :thumbsup: It IS a big deal indeed with an angle grinder. It just laughs at the chop saw.
 

j57little

Active Member
#97
Thanks to Danford1 regarding the advice on recovering from my paint bubble problem. I've gone back and forth trying to figure out what went wrong. Now I'm thinking that my pressure was too high and was attacking the paint layers underneath. In any case, after lots of sanding and repainting the finish is now acceptable. I have to keep reminding myself it's just a mini bike and far better now than it ever was originally!
 
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j57little

Active Member
#98
Assuming no major setbacks, I am getting close to the finish line.

I don't have the "After" photo just yet, but here's the "Before" photo just as a reminder. I've also included some progress updates.

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The original had a lot of good parts, but lots of rust.

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The original manufacturer's plate.

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The major concern is the front end. Unless I'm totally missing something, the front wheel is actually held on by the springs. That's a little scary, but I am proceeding. The springs I am using are a bit longer than the originals, but otherwise pretty close.
 
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j57little

Active Member
#99
Hi Dave,

Chop saws, band saws, etc. just never seem to get the spacers cut exactly square. This method does produce decent results. It's not so good for my drill bits if I go a bit too deep, but hey, drill bits are generally a lot cheaper than custom made spacers.

Thanks,
Jack
 
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Your not missing anything. The front end is just held together with the springs. It is a common way of holding things together for mini's.
Once everything is "threaded" together the front axle bolt keeps the tubes from turning and thus holding them in place.
I was a bit shocked when I first saw it but now I realize it is common place and don't second guess it anymore.

You said the new springs are a bit longer than the old. How much longer? If too long you won't have enough engagement of the smaller tube...

Danford1
 
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