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Looking for M5 X 20 mm Poly-Lok bolts

motoretro

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Have a application where a M5 x 20mm Hex drive bolt w/ the Poly-Lok process is needed. That said, I'm having a difficult time finding a couple of these, I don't mind buying 20 or so as I can use them in the future. Any suggestions?
 
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motoretro

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Does it have to be poly lok, not some other type of patch lock? What head do you need?

Yes, the Poly-Lok have a higher temperature range I'm looking for. Most of the others only are good to 250 degrees. Socket head or rounded head, hex drive.
 
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InDaRed2

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Bossard has a few good options on their hardware, TufLok and Precote coatings. Orange TufLock coatings are good up to 200C and the Precote coatings range from 150-170C.

Not sure how to purchase direct from Bossard but here are links to the 2 coatings, which is available to add to any screw. Low volume is probably going to kill you going direct though.

https://eu.shop.bossard.com/group/en/23084/coatings/tuflok-patch-br-nytemp-patch

https://eu.shop.bossard.com/group/en/23086/coatings/precote-30-80-85

We get all our hardware at work from Endries International. Might be worth a shot to contact them and see what options they have.

https://www.endries.com/
 
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motoretro

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Bossard has a few good options on their hardware, TufLok and Precote coatings. Orange TufLock coatings are good up to 200C and the Precote coatings range from 150-170C.

Not sure how to purchase direct from Bossard but here are links to the 2 coatings, which is available to add to any screw. Low volume is probably going to kill you going direct though.

https://eu.shop.bossard.com/group/en/23084/coatings/tuflok-patch-br-nytemp-patch

https://eu.shop.bossard.com/group/en/23086/coatings/precote-30-80-85

We get all our hardware at work from Endries International. Might be worth a shot to contact them and see what options they have.

https://www.endries.com/


Thanks for the info, temps look better on these. I'm not familiar with the brand although will research them.
 
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motoretro

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#272 is high strength also and I need to easily remove these fasteners on occasion. They're M5 x .8 x 20 mm and are fitted into open ended threaded holes at low torque and are constantly exposed to very hot engine oil on the back end. For these reasons, I'd like to stay away from a thread locking product. Worse comes to worse, I have drilled the heads of two of these and will safety wire them.
 
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matt_i

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If its a wet fastener I'd use a thin coating of grey RTV after blasting everything clean with brake cleaner.

Have to be careful of cured balls of RTV releasing and falling in the oil side of the engine as some bad things can happen, hence why I prefaced with "thin coat".

Since you already have the heads cross drilled for safety wire you just need a fluid sealer in my opinion.
 

SethB

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Loctite blue can take the temperature and releases relatively easily
 
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motoretro

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Loctite blue can take the temperature and releases relatively easily


Which number blue were you referring to?
This fastener is a steel M5 x .8 x 20mm socket head bolt which screws into a aluminum housing with a thru-hole. This area is bathed with engine oil which can reach high 300 degree temps. The torque is 35 inch pounds as it only holds a switch block in place.

I have not come across any light to medium strength thread lockers that are small fastener specific (under 6mm)although with high temp capability. Screwing into aluminum requires a primer for most thread lockers which indicates the threads must be clean. This is a well broken in engine in which getting things that clean will be difficult, every time I clean the threaded holes out, oil seems to migrate into this area. I'm not sure the thread locker will have adequate time to cure before being contaminated with oil.

While this might turn into a safety wiring exercise, it's a tough area to get to, my close up vision is not great and a couple screwed up fingers don't have the dexterity they once had. I can get it done although it might not be pretty.
 
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motoretro

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If you are only looking for , say 2 pcs
You can request free samples from the manufacturer direct
http://www.longlok.com/

After all , you are evaluating them for use, aren’t you ?


I actually spoke to the folks there and they don't do retail, requested I place a order through Fastenal to have their process applied. "Fastenal" is probably not going to send two fasteners to them to have the process applied and turn around and sell them to you, my guess; there's a order minimum. I really have a hard time believing, there's no hardware supplier out there with these on the shelf in any size. Seems like a missed opportunity.
 

BillK

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This area is bathed with engine oil which can reach high 300 degree temps.

Just curious what engine this is running that type of oil temperatures ? Also, just because the oil temperature is that high it does not mean that the casting itself will be.

I would bet that normal Blue Loctite would work just fine.
 
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motoretro

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Just curious what engine this is running that type of oil temperatures ? Also, just because the oil temperature is that high it does not mean that the casting itself will be.

I would bet that normal Blue Loctite would work just fine.

Which Blue Loc-tite were you referring to?

There are quite a few different blue Loc-Tite thread lockers with different characteristics depending on materials, temperatures, bolt size, etc.

Engine is large bore, air-cooled single cylinder. Temps are measured at crankcase plug via a wired in, calibrated temperature probe.

I've looked at quite a few thread locker products and have not found anything that fits the bill in all respects.
 
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motoretro

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I wasn't getting anywhere on sourcing the "Poly-lok" I was hoping to use so went w/ a safety wired hex-drive M5 x .08 x 16mm w/ .032 wire, it took a couple tries although will have to suffice for now. I still think the "Poly-Lok" would be the best fix although wasn't able to get local suppliers to work with me.
G.
 
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