Home Forums Hunting & Shooting Gunsmithing Best penetrating oil?

I have an early Springfield 1903 that I am trying to remove the receiver sight from. Tried Kroil, several soaks, heated with propane torch and Kroil soak again. Still the screws will not budge, looking for suggestions as to what to use as far as a penetrationg oil. I plan to try a hand impact driver after soaking some more with whatever is suggested.

PB Blaster

Just curios gunwizard, you said you used a torch. Did you use indirect heat, as in heating a screwdriver blade on the screw?

I also use and have heard some great stories about PB blaster. Good luck and tell us how you finally get it.

Have you tried giving the screwdriver head a tap while you give it gentle pressure toward undoing it. Sometimes that will break it loose.

I have used Tri-Flo/Flow for 20+yrs for everything from rust preservative to loosening frozen screws etc to sizing lube. Has Teflon in it, always did what I needed. Use it in bores on rifles I don't/won't shoot in awhile and never had one rust but then my digs aren't real humid nor where I live so rust isn't a big issue with a little common sense.

I usually use Kroil or (horrors!) WD-40 on machinery but happened on a mostly empty can of PB Blaster. Worked better than I thought it would. Can emptied before I got much experience but worth a try. Have had occasional luck with VonGruff's tap method. And on rare occasions torque in the tighten direction first to break the threads loose.

And think pure thoughts - good vibes you know.

marko - I heat wherever the torch reaches. Just want it warm enough to assist the penetrating oil to penetrate and soften any threadlocker which, in the case of a Springfield, might be linseed oil. Like to 200F or so which won't affect temper on any steel. Any steel not exotic of whatever temper can handle 400F or so without changing its structure. The hot wrench technique is to heat the hole part really hot to expand that part enough to break rust and loosen the fit a bit. For big stuff unaffected by red heat.

I rank Kroil number one closely followed by PB Blaster. Allow the Kroil to work for a few hours.

It is either a rust or thread locker issue. If you have directed the Kroil or PB Blaster to a couple of different openings to the threads and let it work a couple of hours and that didn't help, then it is most likely heavy thread locker and you will need some more heat.

If the receiver sight is an aluminum Williams, you may be dealing with oxidation of the aluminum. The only solution to that other than drilling the screws out is more heat, to the point of ruining the sight.

Also have you looked closely for any "staking" of the heads? Sometimes they disrupt the body into the screw slot or some other area of the screw head.

Again as staded earlier, try tapping a sharp rap with a screw driver bit in the screw slot, straight down after the Kroil soak/work; this will break rust free, but have about zero influence on aluminum to steel oxidation.

Just an FYI: Anti-sieze should be used on steel screws going through or into aluminum to prevent that nasty bauxite oxidation.

edited for spelling

1/2 auto transmission fluid, 1/2 acetone. It has been proven to be the best penetrating oil of all. Far surpasses Kroil

Actually the tests show it to be as good as Kroil, just far cheaper.

I assume the screw holes are drilled all the way through the receiver. Remove the bolt and fill the holes with Kroil and let it soak down into the holes overnight.

If Kroil doesn't get them loose, no other oil will either. It'll be time to try mechanical means to loosen the screws.

Best of luck.

Mousemilk aircraft penetrating oil and mint oil are supposed to be legendary. I use the acetone/atf with good results.

For tough jobs, I use a mixture of Kroil oil, Type-F ATF (old school ford), Aggressor parts washer solvent, D.O.T. 3 Brake Fluid and acetone. I mix in a 125ml amber glass bottle with approximate amounts as follows: 50% Kroil, and the next remaining 3 in equal parts leaving enough room for 2-3 tablespoons of the Acetone to shake well. Then I heat my screw by using a variable wattage soldering iron and with the iron touching the screw slot and set about 15 watts to draw in the solvent then soaking overnight. If you have the opportunity, reapply solvent a few times during the soaking period and increasing wattage setting if additional heat is needed. This works very well for me on tight screws or bolts.

Have used reverse drill bits with success....

I use and have had great success with Marine PAL penetrating oil.

Gunswizard,

Were you able to get the screw out on the Springfield yet? I'm curious what ended up working for you?

Zeus

Try paraffin. Melt it over the screw and let it cool. Then try to remove the screw.

Try paraffin. Melt it over the screw and let it cool. Then try to remove the screw.

Google Kroil vs ATF/acetone and decide for yourself.

We use CorrosionX in our shop.

BINGO, If you can still find it! very best WinPoor

I have a gallon from cropdusting days, I would fog the inside of my new airtractor wings with it, fantastic on guns!very best WinPoor

The screws are still stuck tight as ever, broke two screwdriver blades. I have tried several applications of Kroil, heat, ATF/acetone, tapped the screwdriver handle every kink suggested all to no avail. I'm going to heat them again after having been soaked overnight with ATF/acetone. Next step will be to try a hand impact driver the kind you use with a hammer, I'll have to grind a bit to fit. Stay tuned for progress report.

Get Roy Dunlap's book on gunsmithing. In it he describes both the paraffin tip as well as heating the part and dropping in a drop of mercury that will pulverize the screw and not damage the threads. Never had to use the mercury tip but have used the paraffin tip to great success.

Good Luck!

Access to mill or serious drill press? After heat/penetrating oil/impact hammer treatment, secure receiver squarely, with a vice that is bolted to the table. A correctly sized bit in the chuck. Firm downward pressure on the screw head and turn the chuck by hand.

No longer have access to a mill or drill press, I have used your tip many times in a 40 yr. career as a Tool & Die Maker.

Oops, just said what Carbon said, and you don't need that great of a drill press (like mine). Guaranteed something's gonna give, maybe half the head of the screw at the slot. But then I've never gotten along well with hand impact drivers.

Mouse milk is really good but if this much Kroil application hasn't fixed it, you are going to need heat or a mill.

Like a Leland Snow Air Tractor?

Corrosion X makes about a dozen products. The one that is PMAd for aircraft is probably not the one to use for guns. I use the stuff specifically sold for guns. It is a green color.

Corrosion on aircraft skin is not a big problem in the Arizona desert! Probably why we have so many aircraft boneyards!