Thorp Air Command - T18.net

The 601 bulkhead assembly drawing calls out for two NAS 177 rivets that attach 601 bulkhead, 602 fitting and the 601-2 together. what are we substituting for it or were can I get them and the necessary tool.
Jon Sanders

_________________
Jon P Sanders

Try an NAS517-3-5 flush head machine screw with a washer and an AN364 (thin) nut. These can be found at Aircraft Spruce. Be careful with your rivet planning as it's a pretty tight fit in there.

_________________
Bob Highley
N711SH
SN 835
KLAL

I believe you can also use a Hi-Lok in place of the 177. JT also stated (as quoted from prior posts) that AN hardware could be substituted for Shear Rivets.

RB

Bob can you elaborate on your comment about rivet planning for the 601 above? It does look like a tight fit in that area with opportunity to do something wrong.
Thanks Stuart

Stuart,

Really, I was refering to setting and bucking the rivets.

_________________
Bob Highley
N711SH
SN 835
KLAL

I am not sure where this came from so I cannot give credit where credit is due but it may be useful to someone.

_________________
Matt Smith
Des Moines, IA
55RC

Matt thanks that document provides some good background on the hi-lock fasteners, I recently was asking my technical advisor what to do about a couple of hi-locks, having never having had any experience with those fasteners this document helps explain a lot more.

Bob re the rivet setting in that area. I thought you might be able to offer some more advice about the best sequence to follow when bucking the rivets that area. Having not started in that area yet would I be correct to assume the best sequence would be to rivet the 601 and 602 together then rivet to the side skin start from the tightest corner and work back outwards then finish with the hi-lock/NAS bolt.

Also I had another question, if you plan on flush riveting the side skin I presume it would be easier to use universal head rivets for attaching the 601 bulkhead to the side skin, given these rivets are mostly hidden by the wing there would be little value in flush riveting that section. Does that sound right?
Regards
Stuart

JT was an aircraft engineer and had all these rivets and the tooling to install them,hence he used them in the T18. I think you will find that most builders substitute an AN 3 bolt in place of the high shears.

Stuart,

You are correct; it might be easier to rivet the fitting to the 601, then install in the plane. Fit all the pieces with clecos before you rivet anything. This will let you see where the crunch spots will be.





You will note some non-standard doublers. This a rebuild project and I had to add some beef due to some poorly drilled holes by the previous builder.

_________________
Bob Highley
N711SH
SN 835
KLAL

Thanks Bob. Interesting to see the close up pictures and visualise that area. It was suggested to me by a technical advisor that the standard doublers in that area could be beefed up anyway.