Need some itty bitty machine screws

On 1/15/2015 8:43 PM, Rex wrote:


When I have a slotted gun screw with a burr in the slot, I put the screw in an aluminum jaw vise, then use a narrow flat face punch and a small brass hammer to tap the metal back into place. This gives a stronger and better looking slot. A touch of cold blue and its good to go.
David
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On Friday, January 16, 2015 at 5:27:50 AM UTC-6, David R. Birch wrote:

Hey, I like that. Thanks for the tip, I'll try it.
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wrote:

Llama used an oddball proprietary thread on those screws. You will not find a box at the ace hdw.
http://www.gunpartscorp.com/Search.htm?s=Screw+&man=LLAMA
Paul K. Dickman
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Could the grip screw hole on the least valuable pistol be bumped up to M4 x 0.7?
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On Friday, January 16, 2015 at 9:12:02 AM UTC-6, Jim Wilkins wrote:

Sure would not want to do that. That's a 33% increase in diameter. On a couple, the grips screw goes through a flat spring. I would not want to enlarge that hole.
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On Fri, 16 Jan 2015 09:02:02 -0600, "Paul K. Dickman"

</snip>
Any one know their rationale for doing so?
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Unka' George

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message wrote:

Before 1947 several countries had their own metric standards: http://en.wikipedia.org/wiki/International_System_of_Units
http://www.gewinde-normen.de/en/loewenherz-thread.html
http://www.gewinde-normen.de/en/french-thread.html
http://www.gewinde-normen.de/en/thury-thread.html
The standards are a compromise between the need for coarse tapped threads in weak materials like iron and aluminum castings and fine threads on screws to maximize the root diameter for strength. That's why we have coarse and fine pitches. Metric standards are in between and not ideal for either, as you'd learn fixing motorcycles. -jsw
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On Fri, 16 Jan 2015 12:43:32 -0500, "Jim Wilkins"


And I thought I had it bad growing up with the 3 different standards. Whitworth was the oddball, metric should have been embraced years sooner by Americans, and most SAE/USS would be gone by now.
As for plumbing, is that a 15/16-27 aerator or a 55/64-27? <sigh>

One learns to use anti-seize on steel bolts going into aluminum housings, too.
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one persists in trying to adapt the world to himself. Therefore,
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wrote:

I've considered removing and coating the accessible fasteners when I bought a new car, and decided against the risk of breaking a machine that's under warranty since the torque specs in the shop manual are for dry threads.
Instead I sprayed the engine and underside with LPS-3 in the hope it would seep into the thread gaps enough to keep out water. Generally they have loosened easily when I did need to remove them years later, but a few hidden ones rusted and were much harder to remove. -jsw
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On Sat, 17 Jan 2015 07:56:15 -0500, "Jim Wilkins"

Didn't the waxy film of LPS-3 (I've not used it yet) cause the engine to act like a dirt magnet?
I bought a tube of aluminum anti-seize back in the '80s to install spark plugs into aluminum V-6 and V-8 heads. Since then, I've used it sparingly and infrequently, so that same tube is still my supply. It sure works well on everything I've used it. I'm glad, because I absolutely hate galling of s/s on s/s hardware and stripping aluminum threads/ruining high-dollar parts.
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wrote:

It can be wiped off flat surfaces.
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On Sat, 17 Jan 2015 10:28:49 -0500, "Jim Wilkins"

Which: the goop, the dirt, or both?
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On Sat, 17 Jan 2015 06:19:03 -0800, Larry Jaques

For stainless fasteners in aluminum in marine service, I started using a Loctite brand zinc antiseize. Expensive, but we'll see next time I have to remove a fastener. Surely better than all the drilling out, etc. to remove broken off ss in aluminum. When I rebuilt the trim-tilt on my outboard, over half the ss bolts broke off, even with several weeks of intermittent heat/penetrant treatment. Which is why boat shops only replace the entire unit for several boat bucks.
Pete Keillor
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On Sat, 17 Jan 2015 10:00:41 -0600, Pete Keillor

This is only of historical interest, but back in the '60s I bought two cans of *lead* based anti-seize, on the recommendation of the tech guys at Rodi Marine in Ft. Lauderdale (who mainained several of the Miami - Nassau powerboat racers) to use with zinc-plated and stainless bolts in "white metal" and aluminum castings. It was for my dad's Boston Whaler.
Anyway, I used it, on the boat and on the Evinrude outboard that we kept in the water, and it worked great. I used it for years afterward on my sports cars, as an all-purpose anti-seize, where it also worked great.
I still have almost a full can left, and I've been told that it's no longer available, like a lot of other lead-powder products. I don't know if that's true of not.
Does anyone else have experience with lead anti-seize?
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Ed Huntress

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On Sat, 17 Jan 2015 11:10:44 -0500
<snip>

No experience, but looks like you can still get some:
http://www.jetlubecanada.com/pages/No60.html
a few others:
http://www.armitelabs.com/products/LP250_Anti-Seize_Thread.html
http://www.superior-industries.com/_1400_anti_seize_product_233.html
--
Leon Fisk
Grand Rapids MI/Zone 5b
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On Sat, 17 Jan 2015 12:55:33 -0400, Leon Fisk

Iteresting. I suppose the people who thought it wasn't available were just knee-jerking about the removal of lead is some other products.
I'm suprised, then, that it isn't used more widely. It was great for really difficult things like exhaust-manifod bolts and so on.
I haven't wrenched an exhaust manifold for close to 20 years, so I'm speaking from historical experience only. d8-)
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Ed Huntress

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On Sat, 17 Jan 2015 10:00:41 -0600, Pete Keillor

Have been there and done that. The usual recommendation for SS bolts and an Aluminum fixture is an insulation paste of some sort. I've used a multitude of different things - I've even used 3M 5200 :-) but the main purpose is to prevent corrosion as aluminum and stainless are far apart on an Anodic Index Chart. 18% chromium stainless is about 0.5 while aluminum is about 0.95. Zinc, by the way is about 1.2. The highest and lowest I see on my chart is gold at 0.0 and beryllium at 1.85.
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John B.
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The home-made hardware on my antennas is made from aluminum, brass and stainless, for example aluminum side plates and pulley sheave on a brass pivot shaft with a stainless screw through the center, greased with LubriMatic marine wheel bearing grease #11400.
They show essentially no corrosion and little wear in over a decade of exposure to rain water and a little wood smoke. I spray LPS-3 on the outside when the antenna is down for repairs, perhaps once a year, but it dries too thick for pulley bearings.
Metal close to the ground and exposed to oak leaf acids isn't so fortunate.
-jsw
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On 16/01/15 15:59, F. George McDuffee wrote:

It might be they had the tooling to make them and so used it. IIRC it was MG with the XPAG engine that had French metric threaded bolts but with Whitworth head sizes as a result of using machine tools moved from the French Hotchkiss machine gun factory to England due to the war.
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On Friday, January 16, 2015 at 9:59:12 AM UTC-6, F. George McDuffee wrote:

My Google-ing led me to a couple of forum entries on "M3-.7". One said it was probably English BS-4 size, which is a very close match. Those are still available in the UK, for obscure restorations. The other (and mentioned here) said the Basque were isolated people who did things their way, to their own standards.
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