Tapping plate nuts under the 739 seat pans

Howdy everyone,
I am finishing up my center fuse and have a question. The instructions say to tap the screws on the outermost plate nuts of the 739 seat pans. How did others accomplish this. Without special tools all I can think of doing is running a drill bit through, but I don't know what size. Any suggestions of course would be greatly appreciated.

Thanks in advance,
Brandon

DO NOT DRILL OUT NUTPLATE

BGordon said:

Howdy everyone,
I am finishing up my center fuse and have a question. The instructions say to tap the screws on the outermost plate nuts of the 739 seat pans. How did others accomplish this. Without special tools all I can think of doing is running a drill bit through, but I don't know what size. Any suggestions of course would be greatly appreciated.

Thanks in advance,
Brandon

Click to expand...

Go to Ace Aviation, Homebuilders Depot or Low Flying Parts department and get yourself the tap that is called for (8-32 I believe). They're less than $10 bucks and if you have a Harbor Freight near by get their tap holders again less than $10 for a set of three. If not the other store should also have them but for more $. Do not drill out the nutplate. You're just to clean out with the tap so that the screw is easier to remove and install in the nutplate due to the close proximity of the side skin. It'll be a bear to get a good torque on the screwdriver if not done. Then you'll be cussing up a storm because of stripped heads and the "These d**n screws are hard to get to!" chants. This is what I did and it worked fine.

Get a couple of hundred of these. They are REALLY handy for all the cockpit panels. A socket or nut driver is way better than a screwdriver.

NAS1801 hex head screws

Tapping nutplate (for ease of screw removal by screwdriver in tight spot) no longer necessary.

Plate nuts

Ok,
What is the tool called...tap and die? Or screw tap? What should I ask for at the hardware store

Tapping

Hi Brandon, I think what they want you to to is to just run a tap through the threads to remove the built in lock in the nut plate. Nut plates are squeezed just a bit on the back side to mechanically lock the screw or bolt a bit to keep it from backing out on it's own. Some places you need to remove the screws more often or have more difficult access so you may not want the locking part. Just chuck up the appropriate (8-32, ie K1000-08, or 10-32) tap in your cordless drill, put the nut plate in your vice by just holding it by an ear, put a bit of lube on the tap and run it through the plate until it cuts the lock out then reverse the drill and your done.

Happy tapping!!

RT

Brandon,

An 8-32 tap like the others said but I had to use an adjustable wrench to turn it a little at a time to keep it straight as it's too close to the side panel. There were only a couple so it didn't take too long.

Boelube

Use boelube!! It makes starting screws/bolts easy and does not ruin your nutplate "locking" feature!