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frumious
April 5, 2010, 08:39 PM
All,

I have a DW Pistol Pack in .357 mag. The shroud for the 6" barrel has a problem. The tiny little Allen screw on the end is rounded out. This screw along with a pin secures the front sight blade. Unfortunately, the screw is halfway loosened. It is neither tight enough to hold the front sight still, nor loose enough to allow removal of the sight.

The screw is visible in the picture taken from the front of the shroud, and the pin is visible in the picture taken from the side. See below.

I tried putting a dab of red loctite on the end of the tightest-fitting allen wrench I have, and then letting it sit overnight. I was hoping to glue the allen wrench in there and loosen the screw that way. I'd have been glad to sacrifice that allen wrench and one set screw. But the red loctite wasn't strong enough and the screw remains stuck.

What are my options? Do I need to have a smith drill it out, re-thread the hole, and just use a bigger set screw? Can I send it to DW? Does DW even exist anymore such that they would work on this 30-odd-year-old revolver (which was my dad's, and I love)?

-cls

http://www.fuzzy-elves.org/images/guns/dw_front.jpg
http://www.fuzzy-elves.org/images/guns/dw_side.jpg

Bill DeShivs
April 5, 2010, 09:22 PM
Treat the threads with a good penetrating lubricant. Let it sit for a day or so.
Find a Torx bit that you can shove tightly into the hole, and turn it out.
If that fails, use a screw extractor of the appropriate size.

James K
April 5, 2010, 09:23 PM
Since there is already a hole there, you can usually use an "easy out" to remove the screw. You can get a set from Brownells or even from many hardware stores. Another way, which I have used, is to drive the next biggest Torx driver into the Allen screw.

If/when you do get it out, I strongly suggest replacing that worthless Allen screw with a Torx or even a slot head.

Jim

mete
April 5, 2010, 09:27 PM
After soaking with penetrant for 24 hours heat the shroud carefully with a propane torch ,the use an easy-out.

frumious
April 5, 2010, 09:58 PM
"Screw extractor" and "easy out"...never heard of these things. About to look them up, though. Thanks!!!

-cls

JohnKSa
April 5, 2010, 10:05 PM
If/when you do get it out, I strongly suggest replacing that worthless Allen screw with a Torx or even a slot head.I agree.

Allen screws are horrible. I see absolutely no reason for them to continue to exist now that Torx is fairly common.

rjrivero
April 5, 2010, 11:38 PM
Hex heads fail a lot. When I encounter one, I tap in a torx driver that is just a bit larger and back it out carefully. If there is any question of locktite on that screw, then heat the screw first to destroy the bond first. A soldering iron directly on the screw will do it for small ones. A heat gun may be needed on bigger ones.

Gunplummer
April 5, 2010, 11:57 PM
Last resort, a left hand drill. Dull the drill until it won't cut easily, run the spindle as slow as possible. They usually back out without much trouble.

ActivShootr
April 6, 2010, 05:04 PM
Screw extractor" and "easy out"...never heard of these things. About to look them up, though. Thanks!!!

Don't learn how to use these tools on your dad's classic revolver. Take it to a gunsmith who has experience in extracting screws and have him teach you. :)

DnPRK
April 6, 2010, 09:02 PM
Like Gunplumber said, get a left hand drill bit. Go slow. The bit will dig in and spin the allen screw out.

James K
April 6, 2010, 09:20 PM
Hi, ActivShooter,

A screw extractor or "easy out" is a bit like a tapered screw with left hand threads, so that when you put it in a hole in the broken screw and turn it counter clockwise (left), it bites into the screw and eases it out. A left hand drill bit might do the same thing, but it will be a lot easier to buy an easy out than a left hand bit, which is a real specialty item. Besides, a left hand bit in a right hand drill will do nothing; in a left hand drill, it will just drill; either way, it won't grab the screw like the tapered easy out will.

In most cases, the tricky part is getting a hole in the middle of the broken or headless screw, but with an Allen screw that is easy as the hole is already there.

Another way that I use much of the time, is to just drill the screw out, using a bit the same size as the minor thread diameter of the screw. Once the rest of the screw is drilled out, there is nothing left except to pick the screw threads out with a dental pick. Note that this works only with a good drill press or a milling machine. With a hand drill, it is too easy to mess up.

Jim

highvel
April 7, 2010, 08:29 PM
Seriously, before you end up with a terrible mess, I would take it to a Smith and for a few bucks be done with it!

zxcvbob
April 7, 2010, 08:37 PM
Left-handed drill bit in a variable-speed cordless drill. The bit will start to drill, then grab, and the screw will back right out. But I agree with letting a gunsmith do it.

frumious
April 7, 2010, 09:29 PM
Thanks all. I ain't skeert :-) I got after the screw with my soldering iron last night...held it on there for a few minutes. Then after it cooled I hit it with the WD-40 and let it sit overnight. Will probably hit it again with the WD-40 tonight and continue to let it sit. On Friday I have a day off so I will drop by a real hardware store and look for an easy-out or maybe an appropriately-sized torx driver. I will bring the shroud with me so I can make sure I'm getting the right thing. Then I'll see if I can get the screw out.

Assuming I can get it out, how/where do I find a torx set screw to replace it with? Wonder what the size/tpi is for this little screw?

-cls

jmorris
April 7, 2010, 09:53 PM
I would suggest against an easy out for a fastener this small as the wall thickness is so thin you will likely expand it against the ID of the hole then break off the extractor. Once you do this, it's game over. See the easy out is two points harder than supermans head and nothing short of an EDM or metal disintegrater will remove it.
The technique I use is using a TIG welder place a dab of weld on top of the set screw then place a nut on the bead and tac the nut to that. At this point you have added enough heat to the screw to expand it in the threads and loosen any loctite, apply just a little torque to the nut, as it cools it will begin to turn when it hits the right temperature. I have done this many times, the most difficult being a #5 allen set screw red loctited down in a novak sight. The entire operation took under 5 min.

I am with the others that suggest taking it to someone that does this for a living. The best outcome if you fail will be making more work (costing more) the worst is scraping the part altogether.

DnPRK
April 7, 2010, 09:59 PM
Assuming I can get it out, how/where do I find a torx set screw to replace it with? Wonder what the size/tpi is for this little screw?
Get the thread count with a thread gauge. Micrometer will determine the screw diameter. McMaster-Carr stocks screws and wrenches.

ActivShootr
April 8, 2010, 08:19 AM
Jim,

As a machinist, I use these tools quite frequently. I just didn't want to advise someone to learn how to use them on a classic firearm that has as much sentimental as monetary value.

Broken screw extractors are much harder to get out than broken screws.

LongRifles, Inc.
April 8, 2010, 08:48 AM
Mix up a 50/50 batch of automatic transmission fluid and acetone.

Dunk the part in it and let it soak for a few minutes.

Now get a got air gun and put the heat on it till she's good and smokin.

Use a small torx tip that'll just barely fit. Tap it in with a hammer. Use a slow and deliberate pressure and if it's going to come out, it will.

If not, it's time to get it in a mill and have it set up and drilled out.

FWIW ATF/acetone beat out all the big name frozen bolt snake oils out there. Kroil, WD-40, etc.

Works great!

Good luck.

C

madcratebuilder
April 8, 2010, 05:09 PM
Broken screw extractors are much harder to get out than broken screws.

+1000

Mix up a 50/50 batch of automatic transmission fluid and acetone.


Works amazing well!

I work with a lot of very small allen heads with my RC equipment. I found that when the allen first strips the head if you pack some valve grinding compound in the hole and then you well get one more shoot at breaking it loose. If that fails a left handed drill bit. If that fails you have the hole for the e-z-out. E-Z-outs are miss-named.

Chris_B
April 8, 2010, 05:39 PM
Comet scouring powder and machine oil slurry, 50/50 or thereabouts

Put the slurry into the stripped socket screw head, and try your allen key again

Old mechanic's trick. Used it many times on old cars

Wildalaska
April 8, 2010, 06:07 PM
$30 fix from a smith

WildwhylivedangerouslyAlaska ™

James K
April 8, 2010, 06:19 PM
What, no one has suggested anointing it with lizard grease and oil of bats' wings, then dancing around it waving a rattle and chanting in ancient Scots?

Works for me.

Jim

brickeyee
April 8, 2010, 08:11 PM
Hex heads fail a lot.

Usually caused by using soft Chinese hex keys in the.

Hex keys should be HARD.
Darn near file hard.

For small screw an appropriate left handed drill bit may be easier to find.

Dull the cutting edge on the tip before going after the screw.
You do not want to drill so much as grab.

Heating just the screw will not help.
You need to heat the material around the screw to expand it the hole.
Heating just the screw will expand it and make it tighter.

jglsprings
April 8, 2010, 09:23 PM
What, no one has suggested anointing it with lizard grease and oil of bats' wings, then dancing around it waving a rattle and chanting in ancient Scots?

Works for me.

Jim

I'm taking notes here Jim. Is that with or without a kilt?

jglsprings
April 8, 2010, 09:28 PM
Assuming I can get it out, how/where do I find a torx set screw to replace it with? Wonder what the size/tpi is for this little screw?

Here is the CZ-USA website. Look around for a contact number. Call and ask about the replacement screw.


http://cz-usa.com/products/by-brand/dan-wesson/

pwillie
April 9, 2010, 06:49 AM
Place gun in deep freezer,leave for two hrs.Take gun out an immediatly use EZ out of size that fit before freezing.

brickeyee
April 10, 2010, 12:29 PM
McMaster-Carr stocks screws and wrenches.

Assuming I can get it out, how/where do I find a torx set screw to replace it with? Wonder what the size/tpi is for this little screw?

Very few gun manufacturers have more than a single style of each screw.

Developing a drawing and finding a sub (or setting up in house) to make more than one screw style is very expensive.

You will also not find that gun screws conform to any standard sizes available from places like McMaster-Carr or other industrial suppliers.

Many gun screws are very fine but shallow threads useable in only the hardest steels with well known composition and heat treat.

Microgunner
April 10, 2010, 12:41 PM
Substitute epoxy for the Loc-Tite.

frumious
April 12, 2010, 08:58 PM
Short version...I'm taking it to a smith this weekend.

Long version: Went to hardware store. Took shroud with me. Bought smallest screw extractor they had. Barely fit. Turns out, didn't fit far enough. Wouldn't bite. Heated end of shroud with soldering gun a few times and after it cooled, drove small flathead screwdriver in and attempted to turn. Nothing. So I punched out the rear pin and removed the sight blade that way. Could then see the pointy end of the screw. No visible damage and appeared to be straight. Filled slot with WD-40 and let sit overnight. Next night heated shroud again. Once it cooled, drove screwdriver back in, attempted to turn. Nothing. Then made the mistake of using a cheap drill bit and turning it by hand clockwise to see if it would bite and i could just screw the screw all the way in and let it fall our the back side. Bit broke off in screw of course.

There's a smith that comes to the bimonthly (monthly?) gun show here...I've talked to him before and he seems to specialize in 1911's, but he does other work too, I think. I'll either take it to him or maybe take it to another guy I've heard does good work that has a shop not too far from me.

Thanks for the advice, guys. I realize I did not listen to it all, thanks anyway. At least I have 3 more "working" barrels I can use while I wait for this one to be fixed.

-cls

frumious
April 19, 2010, 10:22 PM
Well this weekend I took the shroud to the smith that has the shop not too far from me. He got the screw out with an end mill according to the guy behind the counter today when I went to pick the shroud up. The smith was not available to talk to...he had left for the day.

So I guess I'll call him back tomorrow and ask him how much to tap the hole and put a new set screw in. I'm already into it for $85, which I guess includes a hefty "stupid tax" :o But I am somewhat reluctant to tap it myself, as I've only tapped metal once, and that was tricky until I fashioned a jig to help guide the tap.

-cls

orionengnr
April 29, 2010, 09:13 PM
Yep.
After training as a machinist and a lifetime spent as a mechanic, I have finally learned one invaluable lesson:

When you find yourself in a hole, the first thing to do is stop digging. You might be amazed at what a difficult lesson this is to fully internalize.

Even after all this time, and all the lessons supposedly learned, I still have to re-learn it from time to time.