Amount of play on No4 Mk1 bolts

[Edward Horton]

It might amuse you to know that when we were manufacturing new P-40 fuselages there were many times that we found errors in the blueprints as they either did not quite add up dimensionally or did not match the existing original parts/ assemblies. Fixturing was made rather easier using original stuff combined with a slew of photos of the old Curtiss plant! Just using the old documentation was not enough by a long shot. Fortunately, its much better w/ the new engineering.

Here you go, build and fly this one inside your hanger they are much cheaper to build. The motor is a rubber band and you get to build your own prop and then trim everything in flight testing.(or crash it and all start over again)

[jmoore]

Thats what I should have done!!! What was I thinking?

Then Iwould have never ended up in an old sheep barn on the south coast of England tripping over rows of disassembled tiger moths and Fw189 parts whilst loading an ex-soviet P-40k into a container.

Or worked amongst Steven Grey's toys in Duxford...

Or been shanghai'ed to Beaver Falls PA overnight to snatch a P40n and the same day get to poke around in the USAF's P36 at Wright-Pat...

Or travelled w/ a young Aussie (descended from an old tennis star named Sedgeman, I think) to Minnesota w/ a truckload of Allison engines...

Or wondered why a Kiwi (Mike Nickols) was so amused when we took him to a Waffle House!

Or whole slew of other misadventures!

[Surpmil]

If you find you have a No4 with too much 'bolt slop' you can always put a Mk2 stock cross bolt in place of the backsight axis pin and discretely 'pull' the sides of the body in! The stock bolt is a tad too long, so rather than cut the end off an increasingly rare part, perhaps a good quality screw from a specialist supplier and use the round 'nut' from the crossbolt.

Not sure if it has any benefit other than psychological though!

Some manufacturers and vintages are definitely tighter than others of course.

[Edward Horton]

Surpmil is correct, my PH-5C sight had a full length mount screw and when I first installed it I did a really good job tightening the mount screws. I admired my handy work and said “Beautiful job Ed it looks good” they I tried to work the bolt and it was locked up tighter than a drum. (1/8th of a turn too much locked the bolt)

This is why you see so many of these sights with the short screw that doesn’t go through both sides of the receiver.