Loctites: Differences And Their Uses

what is the difference between 242 and 290?

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@b264 what do you use?

I use 243 and 290

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Example of application?

I mostly use 290 unless I don’t want it running into bearings. If it’s near a bearing, might want to consider 243 because 290 definitely creeps

I’ve never had an actual issue with it creeping into a bearing, just paranoid

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so you never use permanent Loctite?

i have never used Loctite so can you explain.
263 is the right stuff for permanent right?

When I need permanent Loctite, I use JB Weld 8265-S Original Steel. Put it on the threads, bolt it together, wait a day, and it will never come apart ever again.

It’s the right tool for the job :stuck_out_tongue_winking_eye:

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Loctite has a HUGE range of different compounds. Some are so thick that they’re applied like gluestick. Some are almost as thin as water. The thinner ones tend to wick into places, which is an advantage in some cases - like being able to threadlock something without taking it apart. In other cases, you don’t want it to wick, such as into a bearing, which would make the bearing an absolute bitch to remove later if need be.

243 is the same as standard blue medium-strength 242 threadlocker, but with better tolerance of oily/dirty surfaces.
290 is a medium-to-high strength wicking threadlocker that can be applied to already-assembled fasteners to lock them without need for disassembly.

I also use 641, which is a removable bearing retainer.
If you want to assemble parts and NEVER have them come apart without a lot of heat and percussive maintenance, you can use 648.

When choosing a loctite compound, there are a couple things to keep in mind:
1: The strength, obviously affects it’s performance in different applications.
2: The viscosity also can be a useful thing to keep in mind, see above.
3: The gap filling properties. Some compounds (648 is one) are designed with tight tolerances in mind - ideally a perfect slip fit or very light press fit is desirable, anything looser will slow down the cure time and significantly degrade the strength. Others are designed with worn-out parts in mind and can handle 0.5mm+ gaps.

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So 290 is like water?
Can it still be used when disassembled or is it meant to be used to an already assembles bolt?
So 290 is used as a more ‘‘permanent’’ solution than 243/2?
Can you give examples on where you would use different loctites on your board to help me understand better each of their application?
Sorry for the dumb questions! :crossed_fingers:

290 is very thin, yes. It can be used before assembly but it really shines for after-assembly locking.

290 is a little stronger than 242/3, under ideal conditions. You’d have to check both datasheets for the exact strength characteristics of each compound on the specific materials you’re using them on - That’s another thing: the strength of the bond is very dependent on the materials. Depending on the compound, aluminum or bronze surfaces can give as much as a 75% reduction in strength vs. bare steel.

Basically 242/3 or 290 are removable and can be used interchangeably. If you have a mission-critical fastener that you want to absolutely NEVER come undone (Unles you want it to, @b264 you smartass) you can use a red (high strength) threadlocker like 262 or 271.

648 is not designed for threads at all, it’s designed for holding (for example) a shaft into a bore. Or a bearing into a housing. Same with 641, but it’s a lot less permanent.

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:arrow_down:

FTFY :stuck_out_tongue_winking_eye:

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680 will give you permanency but with the ability to remove should you need to. Epoxy in any form is more or less there forever so I would not recommend using it in any application that you may want to undo in the future.

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He said “permanent” LoL.

Used that word. Like “affixed until the sun explodes”

Like when a motor mount moved 17 times and it’s either “Stay put, or get shitcanned”

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image

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The thing with 290 is it’s very difficult to get LESS than a drop from the container, and a drop is so ridiculously too much that most of it gets wasted. But I do like 290 and it’s water-thin. Like @MysticalDork said, you can apply it at assembly time and it’s very strong. But you can also apply it after assembly and it wicks in.

Thank you @MysticalDork @b264
And if you want something stronger than 243/2-290 but not permanent like 262-271,
something that can be removed with heat,
What does the job?

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Those are really your choices :man_shrugging: If you want more strength, then you end up with red. If you want less, you end up with blue or 290. 290 is probably about the strongest that I wouldn’t consider “permanent” in that you generally don’t need heat or a hammer to remove it.

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If you have a motor shaft that is completely covered in Loctite 290 with a pulley stuck on it, I have had to heat them up before they would come off, even with a pulley puller. Ironically, the temperature they start letting go at is right around 290 degrees F, I don’t know if that’s coincidence or not. Once you go above that, they will start to be able to be slid off.

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not sure if you can clearly read this but it’s a pretty bloody good run down of loctite-s

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N don’t forget to shake the container n clean surfaces n wait 24 hours.
Some u can heat to speed cure

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