I think I have this handled, but I thought I'd let the gurus have a bite at it. We make stair stringers and have a Torchmate X with a 7x18 table. We've been cutting patterns and templates on it, and are going to start cutting stringers. We're hoping to lay channel up there, cut the holes and carry lines out to the web, pull it off, finish up with a porta-band and start welding rails to it.
So far, everything seems to be going okay, except my holes are typically 1/8-3/32" low. Points on the outside of the stringer seem to be okay and the holes are dead on on the x-axis. What we've been doing is importing the architectural drawings, removing the outline of the top and the bottom of the stringer, shortening the diagonal ends to lay inside the channel, then applying a male online toolpath to the ends and a separate female toolpath to the holes.
I plan to try running my diagonal lines the whole width of the material, as I think the some of the problem with my earlier pieces where I ended up off-center came from the lowest point of the toolpath being set to zero when we import the file. When I set my head in 1/4 inch and draw with 1/4 inch as the zero, it gets closer but not dead-on yet. I think I'm closing in to where I can work with it, but if I could get it dead-on, I'd look like a superstar to the boss man!
In short, I'm not sure I have a problem as much as I'm working the kinks out of cutting a part I'm not familiar with on a format (centered on a channel instead of inside a sheet) that I'm not too familiar with. Any advice or ideas would be appreciated. Thanks!
***and a tip:when you have a college kid trying to cut on a channel, put another channel next to it so if he runs the head off the side, you buy a scrap piece of channel instead of a torch head!***