el-ninio once bubbled...
... are they close enouth to pass two if then through the 2.5" sta? ...
From what I can gather/surmise, the distance between the holes is about 1.5", so you should be able to fit two bolts in on your STA. AFAIK, the two holes allow you to adjust your trim by mounting your tank higher or lower on the backplate, so you would lose this "feature". Judging from backplate phot's I have seen, some manufacturers have added another hole between the two holes most other bp's have. So with that bp, you could drill two holes .75" apart on your STA and still have two mounting positions with two bolts holding the STA in place. Having said that, there is probably no good reason why you couldn't drill the holes yourself if your backplate doesn't have them. If you wanted more range to set your trim, there might be enough space below the bottom hole (where you head is at the top) to drill another hole spaced .75" from it. Do the same on the top set of holes and you should now have four holes per group and three adjustment positions.
I have just realised that I have warbled a lot now and it still doesn't make sense to me. For the sake of clarity, I have scribbled on the Roger Lacasse design to indicate what I am getting at. Your STA would have to be drilled with holes .75" apart for this to work.
I don't know how much of an advantage additional bolts would be. If you are really concerned about the bolts coming undone - use SS Nylock nuts. I must be honest, I can't imagine the bolts coming out if they were properly secured.
One of the STA designs gets around the problem of the STA rotating by making the first bend on the STA down towards the backplate, i.e. the STA wraps around the "spine" of the BP and then bends up and away towards the cylinder. This could also be achieved on a custom unit, with a bit of effort.
WARNING: All measurements expressed in inches were first converted from millimetres to cubic furlongs per BTU-foot and then to the final measurements via a complex algorithm
- measure (your b/p) twice, cut once!
And all this from someone who doesn't even own a bp/wing setup yet (but I am working on it).
I await corrections... :notworthy:
Cheers,
Andrew