Okay. This thing is still driving me insane.
Atleast when you used the pipe already rolled out round as metal and cut pieces out, you didn't have this problem as bad, all though you still did because it ovaled and changed shapes while you were trying to cut it, or you could not complete a perfectly straight edged cut like I mentioned before with the band saw blade flexing and walking side to side, it ends up more of a wave pattern in the experiences I had. Although from looking at these patterns, I'd almost be willing to go back to working directly with the steel, as the edges matched up considerably better than what I'm seeing here with the paper, but they still sucked.
This is with an old CR500 pipe cone I had laying around for a previous project and never used. It came to me as in the first picture, already rolled and welded down the center. I started again with this piece on the Rotax as an experiment and a trial/error type deal more than anything. I wasn't really satisfied with the results of how the joints matched up on it, because I kept running into the "ovaling" issue of the pieces, and the fact that the cut edges werent square enough to weld nicely. I could certainly cover the gaps and do it - it just wouldn't look very pretty.
Here is an example of what I'm fighting with trying to figure out. I understand the problem, its the fact that I'm cutting the shape on one plane, and then basically trying to use it on another, and thats why its doing what its doing. HOWEVER, I cannot figure out how to remedy that yet... How else do you cut it without it being laid flat? Initially I tried with scissors and that was even worse because then it wasn't a constantly circle around, it really waved and crooked as you worked your way around. So, I got the cutting board, that seems to have helped because atleast now its consistently wrong all the way around instead of having high and low places in it, wherever.
So Basically, I set my angle (Which is about 10-12-15 degrees on average I'm seeing) and I make an angled cut, where the cut edge is perfectly straight, using the paper cutter board, as you can see by the picture above.
But what happens when you "unfold" it, and make it round, again?
Your what was previously nice and straight cut edge, now has an incredible bevel along the edges, that won't match up with anything. A pretty significant bevel too, as you can tell. The larger your diameter, the more pronounced it is, and it isn't just a matter of hitting that piece on a belt sander or something to even it out I don't think, the amount of material removal would be too great (so I think at the moment anyways, someone tell me something different?).
Another example, of a sectioned off piece of the card board template, perfectly straight cut edge.
Now, rolled back out into a circular shape - this is what I get.
I understand this is a by-product of cutting it on one plane and axis like I mentioned above, and then changing it, but how in the hell do you cut it on the round plane to begin with?! The paper has to be flat to cut it., and if you use scissors, your even more cattywompass from what I'm seeing. I really thought that this method would allow me to then trace out the metal pieces and make it all be nice and perfect...no such luckWhere I seem to be at, at the moment, is able to resolve one issue or another. I can fix the ovaling, or I can fix the mating edges, but I can't seem to get both fixed together. I half way wonder if on the steel pipe, it wouldn't be prudent to cut each one of those sections apart, and then re-roll them by hand, and then re-weld them
What in the hell do I do here? I'm sure the answer is simple but it sure is doing a good job of hiding from me.
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Originally Posted by Billy Golightly
