Day 2 on Shawn's frame. First thing I did was to make the spacer and internal sleeve to raise the backbone up another 1". It went in low, and way below the bend in the seatpost. This way it was more of a vertical lift. Putting it in the bent section of the seatpost would have raised the backbone, but it would have also moved the backbone back, which we didn't want to do.
Next, I cut the axle blocks from the upper section of the frame, and shortened the lower rails by 2". I mated the axle blocks with the lower rails, then cut the upper rails just in front of the seat crossover tube. I moved to the L/H axle block, and trimmed off the remaining upper rail section, leaving about 1/2" of the rail for a socket for the internal sleeve.
Next, I made sure the upper rail section stubs were ground square, and then cut a new upper L/H frame rail, with the corresponding internal sleeves. I heated the L/H rail stub by the backbone, and pulled it up about a 1/4"-3/8" until it aligned with the replacement frame rail's new angle, and presto!
I slipped the internal sleeves inside the new rail, and was just about to get them into position, when Part-timer Steve showed up. He helped me get the sleeves tapped into place, then I plug welded the sleeves and rail into place. Once Steve was here, he jumped in and did the prep work and sleeves for the R/H side, and bending the stub into alignment, and setting the rail/sleeves, was a breeze on the right. Here's the results, and we have a straight 9 1/4" between the rails all the way down, just like before we modified it.......
Here's the profile view, a nice, straight shot to the axle blocks down the backbone....bye, bye dropseat section, and Shawn has just shy of another 2" of ground clearance, and 15" of backbone height for his monster motor to slide in and out from. Compare the upper rails now, to how they looked in my previous post.
The arrow in this photo is pointing to where we heated the top rail stubs to re-align them, you have to look hard to see they ever moved.
That's where we left off today. Shawn was over, and after seeing the new rear section, decided to keep the stretch in the backbone, and we're leaving the 38 degree neck angle alone, too.
Tomorrow (yeah, no rest for the wicked, but we have a killer TV to watch football while we work!) we're going to tackle rejoining the front downtubes with the neck, which looks a lot easier than it'll be. CDC bent the wishbones, then they sliced of about a 3rd of the radiuses off the insides of both downtubes, then welded them together, forming sort of a single tube with them. It was OK when they welded it all into position in the jig, but when we cut the neck loose, the downtube assembly sprung about an 1/8" to the left up top. We'll have to deal with that before we can do anything else.
I totally dig posts like this. See how it's done. Awesome.
ReplyDeleteThis may be a stupid question, but what I would like to know is how you get the plugs inside the tubes when both ends are attached to the existing frame.Do the tubes get bent to fit them in, then get bent back into position?
ReplyDeleteI'm guessing you're talking about the sleeves in the upper part of the rear legs, where they go into the existing bends in the upper section of the rails.
ReplyDeleteReal quick, normally as a guideline you go 2x's the dia. of the frame into each rail section at the splice. ie, if your rail was 1" in OD dia., you would make your sleeve 4" long, capiche? But, sometimes a guy has to work with what a guy has to work with.
The upper sleeves could only go in the bent sections about 1 1/2" before they hit the bend, so we cut the sleeves on an angle on one end, to get them further into the upper rails. You slip the sleeve into the rail, then you drive it up into position with a sharp punch, through the plug weld holes, until it seats in the upper rail.
The sleeve is a little shorter than 2x's the dia.up top, but there is plenty in the upper rail for strength, plus, that splice area has the seat crossover tube to give it support and strength as well.
Whew....
Interesting info about the upper sleeve. What I am curious about, though, is how you would get the spliced-in section of tube over both sleeves if both ends of the existing frame are already in place.It seems like you would have to spread the frame apart a bit (like about 4" to allow for the sleeve length sticking out of the tubes )to fit the new tube over the sleeves.
ReplyDeleteNo, you do the bottom sleeves the same way as the top sleeve....you also slide them into the new tubing, then you work them down into the sockets in the axle plates just as the top sleeves - you tap them into place, using the sharp punch through the plug weld holes.
ReplyDeleteHey, it's not as simple as it sounds, because no matter how well you prepare the tubing and the sleeves, sometimes you have to work at getting them in place, sometimes they just don't want to move into position easily. That's why they pay me the small bucks.....
I think I get your drift now.....
ReplyDeleteYou don't weld the sleeves into the new tubing, or the old sections until you get your new sleeves worked into place. THEN you weld them into place through the plug weld holes, then you weld the seams.
You don't have to spread anything apart to do it.
Thanks for clearing that up- I can imagine it must get pretty tricky to slide the sleeves exactly where you want them. Do you mark them somehow to make sure they are positioned in the right spot?
ReplyDeleteYeah, I put a few dots on the sleeve with a blue Sharpie, and when a dot shows up in the plug weld hole, it's in position 50/50 to the seam.
ReplyDelete