Which Loc-Tite product?

[The Alaskan]

I am about to have a rifle drilled and tapped for a Williams aperture sight. At the same time, I'm swapping the front sight (dovetail on a base screwed to the barrel) and replacing the buckhorn rear sight with one of those blank pieces that fill the dovetail. I expect to use 242 Blue loctite on the machine screws on the rear sight, but what should I use, if anything, on the front sight and rear sight blank that slide into the dovetail? Any ideas?

 

[zb338]

Ask the guy at the hardware store. I think it's the blue
because it' removable.

Zeke

 

[stoky]

Uncle Mike's Gun-Tite Removable Threadlocker 1631-0 if you anticipate taking something off, for any conceivable reason.
If you absolute positively want it to stay on forever and ever, Loctite 601 Stud and Bearing Mount, green.
Be aware that the color code is inconsistent with different thread locker manufacturers.

 

[W.E.G.]

I'd use Blue on anything that has to do with sights until it showed any signs of shooting loose.

 

[MEHavey]

Or better yet: PURPLE (a thread-locking adhesive that is perfect for gun use.

 

[rcmodel]

There should be no need to use anything on new sight dovetails, as they should fit perfectly without it.

But, if I was gonna use anything, I would use good old Blue #242.

rc

 

[Schwing]

Another vote for blue. I have never had anything move after using it. If you use red or green you will never get it off again without damage.

 

[loose noose]

I go with blue also, makes what you want to stay, where you want it.

 

[The Alaskan]

Sounds like blue it is.

 

[MEHavey]

Purple :banghead:

 

[The Alaskan]

Purple :banghead:

Loctite 243 (Blue) from the Loctite page:

"Loctite Threadlocker Blue 242 is designed for the locking and sealing of threaded fasteners which require normal disassembly with standard hand tools. The product cures when confined in the absence of air between close fitting metal surfaces. It protects threads from rust and corrosion and prevents loosening from shock and vibration. Loctite® Threadlocker Blue 242 is particularly suited for applications on less active substrates such as stainless steel and plated surfaces, where disassembly is required for servicing."

Loctite 222 (Purple) From MidwayUSA:

Lock those screws in place! Purple Threadlocker (222) is great for use on scope base & ring screws, set screws, calibration screws, meters and gauges. This non-wicking formula is recommended for fasteners from #2 through 1/4" and cures in 10 minutes with full strength in 24 hours. Easy to use; simply degrease the screws and screw holes with a quality cleaner/degreaser, apply a drop of threadlocker and thread screws in place. Requires only handtools to remove once applied.

I'm not seeing much difference there, other than that I can get "Blue" and my local auto parts place and not have to order it. Seems to me they're both removable with hand tools.

 

[rcmodel]

Good old Blue #242 has been the gunsmith standard since I first started using it in 1960 something.

I see no reason to change now.

And as you mentioned, it is widely available in auto parts stores everywhere.

(Or at least the Permatex equivalent of it.)
I can tell no difference between them either.

rc

 

[stoky]

Loctite says 242 is for ¼" to ¾ bolts and nuts.
http://www.loctiteproducts.com/p/t_lkr_blue/overview/Loctite-Threadlocker-Blue-242.htm
222 (purple) is for machine screws, #2 to ¼"

 

[BBBBill]

I think folks get too stuck on the color instead of going with the actual designation (222, 242, 243, 262, 545, etc). It's easier to remember a color. Problem for the user is that there are more different designations for different strength/applications than colors used by Loctite.

 

[weaselfire]

Blue has always worked fine for me. Purple also works. Red works, but you are going to need to heat it to get it loose, not good for plastic sights or those with plastic or tritium inserts.

Jeff

 

[The Alaskan]

There should be no need to use anything on new sight dovetails, as they should fit perfectly without it.

But, if I was gonna use anything, I would use good old Blue #242.

rc

Well...

They weren't "new" dovetails (gun manufactured ca. 1947), but as it turns out, you were right; I didn't need any loctite. The fit was so tight, I couldn't even get the front sight seated in all the way with my small hammer and brass drift.

So I dropped the gun off at the gunsmith to get the receiver drilled and tapped for the rear aperture sight, and the guy said he had a small press to finish installing the front sight and aligning it all the way. So I skipped the trip to the hardware store.

 

[rcmodel]

but as it turns out, you were right

Well, Imagine that!!

Glad things fit like they should have fit.

rc

 

[toivo]

+1 on the Purple. I used the Blue on the sight-rail screws of a Browning Buck Mark, and I might as well have welded them on.

For those who aren't familiar with Buck Marks, the sight rail is a structural part, and you have to get at least one of the screws out to field strip the pistol. I tried heating the screws and rapping them with a mallet to break them loose, but it was no use. Eventually I ended up ruining the screw heads (hex). I had to take it to a gunsmith and have him drill out and replace the screws.

Purple!

 

[BBBBill]

Below is a cross section of available Loctite products. There are many more than this. In general the purple compounds are at the low end of the strength range going up through blue, red, and green at the top. However this is not a hard and fast rule. Note the 220 blue low strength and the 290 green medium strength. For that reason please be careful what you select for your own use or recommend to others. Specificity is important in many areas and, IMO, guns are one of them. I've been guilty of this and am trying mightily to avoid it in the future.


Loctite 220 - blue
Wicking grade low strength, low viscosity, removable thread locking adhesive that allows the product to wick along the threads of preassembled fasteners up to 1/4" diameter.

Loctite 222 - purple
Low strength thread locker for fastener diameters of 1/4" and smaller. Its controlled lubricity allows for accurate clamp loads. Parts can be separated using hand tools.

Loctite 242 - blue
Designed for the locking and sealing of threaded fasteners 1/4" to 3/4" which require normal disassembly with standard hand tools. (marketed to individual consumer market)

Loctite 243 - blue
Medium strength general purpose thread locker secures and seal bolts, nuts and studs up to M36 to prevent loosening due to vibration.

Loctite 263 - red
Primer-less, oil tolerant high strength thread locker designed for permanent locking and sealing of threaded fasteners for heavy duty applications where high strength is required.

Loctite 271 - red
Designed for the permanent locking and sealing of threaded fasteners up to 1". Removable by heating to 500°F. (marketed to individual consumer market)

Loctite 272 - red
High temp, high strength thread locker withstands temperatures to 450°F. Provides a fast cure on most surfaces. Recommended for bolts up to 1 1/2".

Loctite 290 - green
Low viscosity, medium strength, wicking grade, green thread locker wicks along the threads of pre-assembled fasteners to secure them in place. Typical Applications: Bolts on alternators, air conditioning belts and distributor clamps, carburetor adjustment screws, and hairline cracks. Disassemble with hand tools. In rare instances where hand tools do not work because of excessive engagement length, apply localized heat to nut or bolt to approximately 250 °C. Disassemble while hot.