Old screw woes

[sumsmug]

Hi all,

I'm currently restoring a 66 caravel, generally its in great condition, but some the screws have been in place 44 years and are extremely reluctant to let go og my airstream now. The biggest problem I have is heads that are corroded and impossible to "unscrew".

I've been drilling these out a bit an using a black and deacker (Amazon.com: Black & Decker 16270 Screw Extractor Set, 5-Piece: Home Improvement ). To be honest, its a bit rubbish, I've snapped 2 of the screw extractors already and drilling the hole for them is almost impossible for some of the harder screws.

This has got to be a common problem for AS restorers everywhere. Does anyone have experience with other extractors kits or methods to share with the group? Old screws are really slowing down my restoration and driving me nuts

[gwchitty]

Yes, old screws and corrosion work against us. I tried to get a really firm grip with the screw driver on a fresh screw slot. If it stripped the screw slot off, I sheared the head with a small cold-chisel. If you're doing this in the floor c-channel, you will probably be replacing the plywood with the headless screw anyway. If its in the wall, you may get a second chance to grab the body of the screw with vice grip pliars later to remove it. Keep trying and eventually you will run out of screws and begin to tackle the floor bolts by drilling the heads off.

Cheers,
Cosmos

[BrianY]

I am in the same boat. I developed an extreme dislike for rusty slotted screws. When one of these strip out, I take my dremel with a cut off blade and cut a new slot 90 degrees to the original. With a fresh cut slot, I am usually able to get the screw out.

[BIGED52]

sumsmug, Try to use this trick on the screws. Take a medicine dropper (the childrens plastic ones work best) and drop a few drops of Muriatic acid on the area around the head of the screw and down the threaded shaft of the screw if accessable. Use an appropriate amount and don't drip it on other areas of the trailer. This is tricky on screws that are horizontal but can be done if you take your time and keep the excess from running down the surface that the screws are into. Wait 10 to 15 minutes and using a regular screwdriver (not a power one) try to back the screw out of the aluminum. The corrosion may take two or three applications of the acid to do the trick but the steel of the screw will evetually release from the aluminum (the corrosion/rust will be what the acid will dissolve). If the screw head (phillips or standard) is stripped out cut a new flat slot onto the head with a file, or if you have one a dremel tool works much better and faster. Be careful of the surface surrounding the screw head. For those screws that have the head broken off you can use the same trick with the acid and then drill into the screw and use you extracting tool. The Muriatic acid will break these screws loose and allow easier extraction in almost every case. If the screw has a head stripped or broken off and there is enough of the threaded shaft above the surface you could use vise grips to turn the screw out once the acid does its job. Hope this helps. Happy Trails, Ed

[68 TWind]

I use the Dremel trick like BryanY. Most of the time with a new slot and proper fitting screw driver blade they would come out. One tip, is that when you cut the new slot with a dremel cut off wheel the slot is square on the sides. If you will use a hollow ground screw driver bit like the ones designed to be used by gunsmiths, it will grip much better and not slip out where a regular screw driver will slip. Another trick I learned from an old airplane mechanic it to buy you a couple of screw drivers with 2 foot long blades. With the long blade (Harbor Freight has them) you can concentrate much more weight directly on the screw head and prevent slipping. This is especially true on the screw that are counter sunk into the cabinet frame and hold them to the floor. Many times when working on airplanes if you break the screw or round the head you had a major problem and I watched my buddy remove "impossible" screws with the long shaft screw drivers.

[samb]

Here is another "trick" that I used to remove the hundreds of rusty screws I encountered on my 1949 Boles Aero when I changed them all to stainless steel. Get the flat or phillips that fits and is in good shape. Place it in the slot and hit it two or three times fairly hard with a hammer, driving it into the slot even farther. As hard as you dare without distorting the aluminum or damaging whatever it is in. Only then try to back the screw out. In a lot of cases the jarring breaks the grip of the corrosion and allows removal.
This worked for me about 85% to 95% of the time to break loose rusty iron screws in aluminum.
When this method doesn't work you can resort to any and all of the methods described above. When none of the above work that is the time to use your vocabulary to its fullest extent. That does not get the screws loose, but will sometimes make you feel better.
Sam

[sumsmug]

All fine suggestions, I will try the dremel trick next week, plus a whopping 2ft driver

[Shacksman]

I have a pair of these screw pliers and they work very good at getting out the rusted screws.
Screw-Pliers Dot Com

[HiHoAgRV]

For non-c'sunk screws...
I've had good luck with grabbin the head with ViceGrips...1/2 turn at a time is kinda rough on the wrist though...

[Archersfin]

Go to any local Auto Parts store and get a Hammer screw driver with assorted tips. I'm sure the Box stores have it also. This is the one you hit with a Hammer. Smack the stubborn screw with a regular screw driver. Now use the Hammer driver to loosen the screw. Once loose remove with a power driver.
Worked for me.

[alclad]

never hurts and is always good: spray a little liquid wrench every day for a week before and let it work itself into the threads.
worked well on my 49+ year old screws.

[Stumpjumper]

When I know they will be tough, I take the following steps:
1. If in metal only, soaking with a rust penetrant for a few hours or day can help.
2 Place the appropriate head style and size into the screw, while pushing and turning slowly have someone tap the back of the screwdriver, this may "impact" loosen it.
3 If the screw stripped anyway: using a rotary tool cut a slot across the top of the screw for a flathead screwdriver. Don't cut into the screw shaft as this may weaken it and it will break. Safety glasses reguired!
These steps have removed 99% of all my tough screws, sorry nothing is fool proof and it is still slow, but works.
Good luck,
Dan

[Ganglin]

Originally Posted by Archersfin

Go to any local Auto Parts store and get a Hammer screw driver with assorted tips. I'm sure the Box stores have it also. This is the one you hit with a Hammer. Smack the stubborn screw with a regular screw driver. Now use the Hammer driver to loosen the screw. Once loose remove with a power driver.
Worked for me.

We had the best success with this method also. Soaked the screws over night with PB Blaster. Tapped them with a regular screw driver and hammer a couple times then used the impact driver. It worked best if you used it right out off the gate rather than as an option once you have the head chewed up.....

7 Piece Reversible Impact Driver Set

[Air-Hal]

Before cutting the heads off, I recommend spraying them with PB blaster and then soaking for 2-24 hours. Put on a pair of safety glasses, to prevent eye damage from flying debris when using an impact driver/dremel/grinder. If they are Phillips head, you can try an impact screwdriver. An impact screw driver is usually driven with a hammer, where the force of the hammer simultaneously holds the bit in the screw and twists it out.
I have not purchased an impact screw driver recently, but I think they are available for about $40, probably with different size bits. Impact driver bits are more sturdy than regular bits, as they need to work with the full force of being struck by a hammer.
My experience is that an impact driver works when other methods fail. As a last resort, cut the heads off, as suggested.