I guess I must have crooked eyes because everytime I install a turbine in an airframe, I have a heck of a time eyeballing the thrust line. So after trying to use straight edges held up to the outside of the turbine (with no luck) I came up with this little device. What do you think?

The black cone I had laying around and I believe it was some sort of protective cap over a large insulator for power generation lines. But it could easily be made from thin fiberglass over a mold or even rolled out of stiff cardboard. I trimmed it so that it would be a tight fit onto the inner tailcone of my P120. I made sure that it didn't contact the EGT sensor. I slide it over the inner cone until it comes up snug against the inside of the outer cone.

Then I cut out 2 centering discs. The smaller one is balsa and is 2" diameter. The larger is liteply and is 2 5/8" diameter. Both are drilled for the size of the arrow shaft. I glued the smaller disc onto the one end of the shaft. I slide the small disc and shaft into the black cone until it is snug and then slide the larger disc down the shaft until it centers in the end of the cone.

The first pic shows my alignment tool. The second pic shows a misaligned turbine (exaggerated). Pic 3 shows the alignment tool installed in the misaligned turbine. Pic 4 shows the turbine and alignment tool after I have straightened it.

I also tried this tool on my EuroSport by inserting the tool into the turbine and then sliding the tailpipe into position. What appeared as a perfect alignment to my eyes, showed to be slightly off with the alignment tool.