Junglepilot

Junglepilot

Well Known Member
Those 8R8 screws [just for example] are very soft and the Philips slots get mangled pretty easy, especially if you use an electric drill driver and don't get a good set on them first, or their just too darn tight.

Do this:

  1. Get a tube of Permatex Valve Grinding Compound at auto parts store.
  2. Dab a tiny bit of the compound on the screwdriver tip
  3. This will help the driver tip to stay in the Phillips Head slot without slipping out whether tightening or loosening the screw.
 
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Good tips, and I'll add another - buy GOOD screwdrivers and/or bits. It is amazing how well a properly built Phillips can grip a screw!

Paul
 
Ironflight said:
Good tips, and I'll add another - buy GOOD screwdrivers and/or bits. It is amazing how well a properly built Phillips can grip a screw!

Paul
Click to expand...

Paul's right. Snap-On bits have gripping ridges that help, and some Craftsman screwdrivers have diamond dust coating the tip.

V
 
I've got a few good Snap-on Phillips bits too. They work great for removing Phillips screws. I don't use them for inserting, because I replace with Robertson or Torx heads... :)
 
Better yet is to replace them all with 6 lobe drive (Torx) screws.
 
9GT said:
Better yet is to replace them all with 6 lobe drive (Torx) screws.
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I bought some #6 torx SS screws and found they actually stripped out easier that the AN phillips head. Maybe the SS ones are just too soft. I was both surprised and disappointed.
 
I always put a rub of Boelube on the threads of new screws. There is no need for the threads to have that much resistance in the nut plate. If you just find ways for the screw driver to bite the head without easing the stress in the threads you will start breaking the screws off. This issue is a downside to having a cowling with no hinge pins but hundreds (feels like it) of #6 and #8 screws.
 
Problem nutplates

In many places I've found nutplate friction is much higher than wanted, leading to damaged screw heads. To fix that problem, simply tap-out the nutplate before installation. A small bit of Loctite can later be used if wanted.

And, dittos on the Wiha screw drivers... they're superb.
 
Bill Wightman said:
In many places I've found nutplate friction is much higher than wanted, leading to damaged screw heads. To fix that problem, simply tap-out the nutplate before installation. A small bit of Loctite can later be used if wanted.

And, dittos on the Wiha screw drivers... they're superb.
Click to expand...

Rather than run a tap through the nutplates, I burnish the threads. Get some hardened hex socket machine screws of the appropriate sizes. Before each nutplate is installed, clamp it in a soft jaw vise, put a bit of Boelube on the screw, then run it into and back out of the nutplate with an electric screwdriver and a hex bit (Wiha, of course :D). Rinse with lacquer thinner or other solvent, and you're ready to go. No binding or galling, still plenty of prevaling torque.
 
RV7AV8R said:
I bought some #6 torx SS screws and found they actually stripped out easier that the AN phillips head. Maybe the SS ones are just too soft. I was both surprised and disappointed.
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I had the same results. I bought enough SS #6 torx screws to replace the vast majority of #6 screws on my airplane thinking they would not get messed up as easily. Wrong! The heads stripped out much easier than the Phillips head screws. I have since replaced all those SS torx back to Phillips.
 
I agree that a good driver is a must for Philips screws. In almost 10 years and 9 annual inspections, I've maybe had to replace a dozen screws total. 100% of the screws on the outside of my plane are SS flathead #8 x 3/4" screws (don't have the AN desig. handy). Wax and debris will affect torx more than Philips also, in my opinion.
 
size matters

And all phillips screwdrivers are not the same size. Use the correct ones for the screw heads.
 
Robertson are excellent, but..

Snowflake said:
I've got a few good Snap-on Phillips bits too. They work great for removing Phillips screws. I don't use them for inserting, because I replace with Robertson or Torx heads... :)
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Where do you get aviation grade Robertson if you are not in Canada?
 
Good tips a must...but what if...

My reason for posting was from my bush flying experience. We had a hard time keeping good screw drivers in Ecuador, and forget buying them in country. In the US bubble we are blessed to have Wal-Marts everywhere.

When flying into the rain forest we always carried a tube of Valve Grinding compound on-board. We kept a tool kit on board but often the tools were kinda cheap and more than once I repaired a connection with my Leatherman. It has a good tip but the VGC always assured the screw came out.

Ever been on a trip and needed to get a screw out of a nutplate/nyloc nut and no good tools nearby but for your trusty Leatherman/SAK and a pliers?

Cheap, light insurance on a trip.

Just sayin' :)
 
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Short #8s are great

If you are in the build phase, buy a box of 1/4" long #8 phillips head screws.

They are just the right length to hold panels without engaging the locking mechanism in the nutplates.

Install the AN 515 screws when you are done.

The short screws work for some c'sunk 509 holes too.
 
Corrisive Enviroment Trick

When I was operating helo's out of St. Thomas, one of the tricks I learned from VI Seaplane Shuttle group, who operated Grumman Mallards in the salt water, was to replace all the hardware with stainless and then use "Lubriplate" in the screw holes. Almost always...after doing these recommendation, I was always able to remove screws...even with bad tips.

And yes, on several occasions my Leatherman saved my bacon. Don't leave home without it.
 
I'll also chime in for Wiha, I've got a number of the small precision sets at work for working on electronics and whatnot (~$50/set). I've been a serious screwdriver snob since I got into Gunsmithing about 10 years ago.

One interesting thing that I was actually contemplating today was that it seems that the more expensive a piece of gear is the softer the screws are that are holding it together. While replacing a $4k reverb PSU today I found that they recently started including new screws with the insanely overpriced PSU.:rolleyes:
 
Screw removal

I just pulled 100+ 8R8 holding on the fuel tanks. I used a new screw driver but if that didn't grip I switched to a driver with replacement tips. I changed out the replacement tips several times using the Dewalt P2 tips when they got dull or collected metal shavings. I tap the stuborn ones with a very small hammer to set the tip in the paint and try to keep the screw driver 'in column' where it felt 'locked in' and then rotate.
 
Try Valve Grinding Compound

That's just the situation where Valve Grinding Compound is a wonder drug. I doubt you would have had to change tips with VGC with one exception. Read on.....

When we used to remove the fuel tank covers for 1000 hour wing heavy inspections on the MAF 206 bladder tanks, those screws were painted over and put in with a Pro-Seal type material.

Using a dab of VGC on the driver tip 99.9% of the time broke the screw loose without even slight damage to the screw. If it didn't come loose, it gripped so well the tip of the driver bits occasionally broke. We had a 30 year history of that working. That's some serious grip there.
 
What an incredible tip!!

Junglepilot said:
Those 8R8 screws [just for example] are very soft and the Philips slots get mangled pretty easy, especially if you use an electric drill driver and don't get a good set on them first, or their just too darn tight.

Do this:

  1. Get a tube of Permatex Valve Grinding Compound at auto parts store.
  2. Dab a tiny bit of the compound on the screwdriver tip
  3. This will help the driver tip to stay in the Phillips Head slot without slipping out whether tightening or loosening the screw.
Click to expand...

I kept this in the back of my mind as I have a lot of SS flat and cross head screws on my plane. Today I had to remove the 8-32 SS screws that secure the cover in between the canopy and the cowling (don't know the proper term) on my -4. I have done this numerous times over the last couple of weeks to work on instruments, wiring, etc.

There were always a couple of screws that would slip, strip, etc. Today I tried the valve grinding compound trick. I could not believe how well it worked!! Not a slip, twist, strip, nothing but easy extraction and insertion.

Thanks for a wonderful idea, and thanks to VAF.net for making it available!!

Chris
 
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