Loctite primer necessary?

[upnorthandpersonal]

Actually, I think I'm mixing 271 with 272. 271 is medium strength, 263 is high strength (and so is 272).
In any case, either will do, one just needs a primer.

 

[fafrd]

It's not 'obsolete' as far as I know. It has certain properties (like needing a primer) and it will still be available (as far as I know, it's still produced).
It's just that 263 is easier since it doesn't need a primer and covers the same use cases that 271 does.

Fair enough. I’m miffed partly because I asked two of the red-vested ‘experts’ whether their Loctite Red needed primer when used with stainless and aluminum and was assured that ‘no, it did not.’

Lighting was too poor to read the tiny print in the store or I might have figured this out before purchasing.

I had my first cell and grubscrews cleaned with acetone and was about to open the package when I thought I’d read the directions in the bright light of day.

 

[Darkstar]

I’m gearing up to secure my first stainless grubscrews into aluminum 280Ah terminals with Loctite Red and see that the instructions state that Primer is needed when both surfaces are ‘inactive metals.’

Stainless is an inactive metal and so is Aluminum, so it seems like primer is required.

But I believe I’ve heard from many who have used Loctite Red on this board that primer is not needed if you have cleaned the threads with Acetone (which I have done).

So advice for a Loctite-newbie appreciated - do I need to bother with primer after threads have been cleaned with Acetone and dried?

I used the primer on my stainless studs. I found the the red dried and became safely fastened much faster with the primer. Also, I found JB Weld does not hold nearly as well.

 

[EcoRV]

I used the primer on my stainless studs. I found the the red dried and became safely fastened much faster with the primer. Also, I found JB Weld does not hold nearly as well.

Any ideas where i can find the Loctite Primer N 7649 locally? Amazon shows delivery in about 2 weeks. Im in Dallas and not finding it so looking for better search suggestions.

 

[OnTheRoadAgain]

I've never used the primer.
I just had to remove some nuts with red loctite from some stainless bolts I "thought" were semi permanent.
Almost twisted the 5/16 bolt in half

Could you use Blue Loctite instead?

 

[Bob B]

Any ideas where i can find the Loctite Primer N 7649 locally? Amazon shows delivery in about 2 weeks. Im in Dallas and not finding it so looking for better search suggestions.

I ordered some off of Walmart.com ...... don't remember how long it took to get it.

 

[cinergi]

My answer is yes because some of my loctite'd studs did NOT hold (I was able to back them out) and I didn't prime them.

 

[EcoRV]

After literally 2 hours searching i found a reference that Loctite Klean and Prime is the automative equivalent of 7649.
So the Klean and Prime and 263 can be purchased off of Amazon.

 

[Just John]

I’m gearing up to secure my first stainless grubscrews into aluminum 280Ah terminals with Loctite Red and see that the instructions state that Primer is needed when both surfaces are ‘inactive metals.’

Stainless is an inactive metal and so is Aluminum, so it seems like primer is required.

But I believe I’ve heard from many who have used Loctite Red on this board that primer is not needed if you have cleaned the threads with Acetone (which I have done).

So advice for a Loctite-newbie appreciated - do I need to bother with primer after threads have been cleaned with Acetone and dried?

First one I tried did not set in 24 hours. It does if you use the primer.
Note that threadlocker klean n prime takes a week to deliver to my location, but it does make the red 271 set.

I think it might set without if you purchased cheaper "stainless steel" made in China. I have both, cheap Amazon grubscrews, and (noticeably higher quality) purchased from McMaster Carr.

 

[ArthurEld]

Loctite 263 is made for studs and claims to be primer less. https://www.grainger.com/product/LOCTITE-263-Series-High-Strength-Primerless-5HYJ0
Primer can be used if you want it to cure faster or if it makes you more comfortable.
Mine dried hard as hell after a couple days without primer

 

[upnorthandpersonal]

Loctite 263 is made for studs and claims to be primer less. https://www.grainger.com/product/LOCTITE-263-Series-High-Strength-Primerless-5HYJ0
Primer can be used if you want it to cure faster or if it makes you more comfortable.
Mine dried hard as hell after a couple days without primer

Same here. Did not use a primer.

 

[Pierre]

What I would do is put a locknut onto the stud with red loctite and then use a lesser glue putting the stud into the battery terminal. This way you can put a spanner onto the stud to fasten the ring terminals and also loosen the stud if required.

 

[Just John]

All I can do is give my personal experience. Using stainless steel grubscrews (6mm x 25mm) from McMaster Carr, after 24 hours I was able to remove the grubscrew with my fingers, no tools needed. After 48 hours, almost the same, I did use an allen wrench to break it free, but it wasn't difficult (probably could have done it via fingers if I'd tried hard enough). This was red loctite, 271.

Amazon.com: Loctite Threadlocker Red 271,0.20 fl. oz(209741) : Automotive

Amazon.com: Loctite Threadlocker Red 271,0.20 fl. oz(209741) : Automotive

smile.amazon.com

I'm sure others may have different experience, since some versions of stainless steel are slightly magnetic, they likely have enough metal ions to set it. Mine did not, and the aluminum did not.

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

 

[Frank in Thailand]

FYI
Primer is ALWAYS needed with stainless steel and Aluminium.

The latest Henkel user guide, 272 isn't used, only 263, and they still talk about primer for aluminium and stainless steel.

I've tried both.
While without primer after a few days you get a reasonable bonding, it's not what it should be,and you can release the grubscrew without ripping out threads.

It doesn't even stick to the stainless steel... (Mostly)

Grubscrew and thread where clean and cleaned with acetone before applying anything.

Sorry guys..
It's probably weaker then superglue...

That does not mean you all need to unscrew the grubscrews, clean, apply primer and again Loctite...

Don't change a winning team.
If it now works, let it stay lie this for the next 10 years or so.

If you are just setting up..
Do use 7649 primer !!!