All,
I have read through the posts, references and newsletters and I am about to final drill to size the attachment lock pin holes in the 215 and 315 fittings. My fittings came pre-drilled to 1/2" hardened and plated with only a very slight offset in one of the holes on the RH wing side (likely from heat treating). My plan is to step drill to 17/32, 35/64, possibly ream to .5615 and then final ream the holes up to the .5625/9/16" pin size.
My set up for drilling and final reaming is going to be similar to ljkrume's shown from his gallery album, shown below during drilling.
I am struggling to see any other way to do this. Everything I have read and the references I see say to "ream to final size on assembly". Well, once inner and outer wings are assembled it will be very difficult to final drill/ream. This would have to be done by hand . . .not my idea of fun. If I go ahead with assembling the 315 to the outer spars which are built minus the 315/rib mounting holes then I will kind of lose any way to do a slight adjustments when drilling/mounting the 315 to the spare and doing dihedral checks as they are already assembled. These 215/315 fittings seem so close to the correct angles when clamped together and temp assembled (they are tight!) and sitting on the catches that I believe they will be good to go.
My set up was going to be with my smaller bench drill press on top of my work table, but I am going to use my larger standing press as it will be more stable and is a better drill press than the smaller one. I will just clamp things together and level the inner spar and shim/clamp the pieces together.
Any recommendations from anyone who has built a T-18C or S-18 wing that has some words of advise or a better approach to this other then as done by ljkrume or how I am suggesting? I think it will be fine as long as everything is level and clamped tight when drilled/reamed. I am just a nervous item to do as it is not an area you want to screw up on. I am finding out on some of this stuff you just have to read everything you can, ask questions in hopes of getting some advice . . . but in the end you just do it and learn as you go . . not a lot of T-18 builders around in my area to consult with.
I am asking as there will bound to be someone who is building a new project from Jim at Thorp Central that will have the same questions!
Rob
