Best grease for puller (conical part)

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Hi, What is the best type of grease for the conical tip/part of a puller in order to avoid damage to both the conical part and its counterpart (part of the mechanical assembly). Picture for reference: [Linked Image from tenaquip.com] Or is there a better method such as slipping a small piece of thin guage brass sheet metal between the parts? Lucas
 
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Originally Posted by LucasDK
Hi, What is the best type of grease for the conical tip/part of a puller in order to avoid damage to both the conical part and its counterpart (part of the mechanical assembly). Picture for reference: [Linked Image from tenaquip.com] Or is there a better method such as slipping a small piece of thin guage brass sheet metal between the parts? Lucas
Neither, Use a shaft protector between it and the shaft and use anti-seize as the lubricant. No grease known will maintain a significant film when its turning under load and you will need the metal ( preferably nickel but moly will work ) for the lubricity when really putting force on it Same for the threads.
 

JHZR2

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Originally Posted by ABN_CBT_ENGR
( preferably nickel but moly will work ) for the lubricity when really putting force on it Same for the threads.
Youre implying that Ni in anti seize is more lubricious than an MoS2 paste? Also need to be very specific that youre implying Ni Anti-Seize if that's the case, as intitially its just stated generically.
 
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Originally Posted by JHZR2
Originally Posted by ABN_CBT_ENGR
( preferably nickel but moly will work ) for the lubricity when really putting force on it Same for the threads.
Youre implying that Ni in anti seize is more lubricious than an MoS2 paste? Also need to be very specific that youre implying Ni Anti-Seize if that's the case, as intitially its just stated generically.
Should have been stated better but I didn't think it mattered at the technician level but you caught it so others will do. This actually comes from tests done in conjunction with OTC on pullers for a project. We actually tested numerous lube and protector configurations back then. There are two parts to that screw- the physical loading ( the puller thread is a compromise between screw and ACME) and then the puller being harder than most shafting so it grinds in. Moly is the superior lubricant as solid films lubricants go but under those loads and galling (not to mention a proper shaft protector should split under the loading) the nickel gets impregnated (almost gilding) ans has superior performance. It should have been better stated that is on ISO press fits Moly would be excellent and probably be smoother that anything else. You get into heavy ISO interference fits then moly will go boundary real quick ( so will the nickel too) but then it matters. Not specific to the puller illustrated but on the posi-lock puller, moly is recommended for the OEM end cap protector but its at the same hardness as the screw whereas a shaft protector isn't.
 

JHZR2

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Interesting... Thanks. Had curiousity for two other reasons: 1) I made a tool to press subframe bushings into my 82 300CD last weekend. I used moly paste on the 5/8" threaded rod, and didnt even use a washer between the cast iron pipe of my "tool" and the nut... and it spun easily and really well. 2) I have a Klann spring compressor for old MB diesel long front springs. Its the only kind that works well and safely. it must have a 20mm threaded rod in it. And it recommends moly... Thus why my curiosity was peaked... If there's something better, its always good, especially if its something that I have, like Ni anti seize (which Im sure has graphite and moly in it too).
 
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Originally Posted by JHZR2
Interesting... Thanks. Had curiousity for two other reasons: 1) I made a tool to press subframe bushings into my 82 300CD last weekend. I used moly paste on the 5/8" threaded rod, and didnt even use a washer between the cast iron pipe of my "tool" and the nut... and it spun easily and really well. 2) I have a Klann spring compressor for old MB diesel long front springs. Its the only kind that works well and safely. it must have a 20mm threaded rod in it. And it recommends moly... Thus why my curiosity was peaked... If there's something better, its always good, especially if its something that I have, like Ni anti seize (which Im sure has graphite and moly in it too).
To add a point of clarification (I need to remember to refresh my memory before commenting on parts of very old projects) This was about damage to the thread/nut connection ( the nut is 3-5% harder than the thread to pull tension) and under load/shaft deflection and all that. Also the contact geometry ( different countersink angles on shafts and the hardened point ( which is why the shaft protector is softer so it will "mold' to the drill point) We basically did oils, greases and anti-seized for performance, safety, load reduction studies. The moly we used was a grease. If you were using a branded product like Bostic "blue moly" which has moly but nickel and is designated as an anti galling compound- that would have been considered a nickel anti seize in our tests because we were not commissioned to test individual brands. That could be a distinction with a difference based on our design of experiment sorry for any confusion.
 
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Had some questions on the above example- we were commissioned as a result of an incident involving an injury and this study was a requirement of litigation. The purpose was to develop the approved pullers for specific tasks and work processes and job plans etc. It was not testing various lubricants (in terms of performance) or specific pullers ( we tested all types the facility used which was pretty much every one that exists) and the key thing was establishing a force estimate that determined what was acceptable to what level so we did destructive testing for the high threshold. It wasn't "product testing" in terms of performance or quality in the traditional sense- sorry if that misled anyone.
 
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?? I've never bothered, just use any random lithium based grease on the threads. Trying to slip some softer buffer material between them, or any goop to make it more slippery, seems like a real pain and fiddly thing that makes it harder to do the work. I want the tip planted and to stay put, not have some shim that can cause it to fly off in some direction. The key to that may be to use a decent quality puller with a sufficiently hardened screw. Besides, if the tip doesn't stay super sharp, what did it matter if you were effectively dulling the contact area anyway with the shim?
 
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