Does Loctite alter torque on scope rings

[4th_point]

Cases like this, I would look at the tool used to apply the torque.

Fat Wrench may have gone belly up.

I tested several of them. There was some error with each as I recall, but one was way off. It was repeatable but the value on the scale didn't match the torque applied. Another would not always click.

The only time I have seen tubes severely crushed was from a defective tool.

 

[wapitibob]

The design of the hyperlite top ring half would easily allow them to taco and pinch a thin scope tube without a whole lot of torque on the screws.

 

[Wrench]

There is also the "feels good" and mark method that works well.

Think about what you are doing. If you have a narrow cap with 48tpi screws, you are going to need to be more careful than a wide cap with 32tpi screws.

Snug it up to contact, square it up and mark it with a sharpie or paint.....fire a dozen rounds and check for tube slide.

I have a sightron s8 in their 40mm rings which is a very heavy scope in very narrow rings and it lives on an edge that isn't exactly friendly to scopes....but it stays put and hasn't crushed.

6 screw caps are a tough one to get right at first. You'll be chasing torque for a long time as you try to equalize the screw load. Do not load one edge or you'll crush it.

 

[sndmn11]

I have had two sets of these Hyperlite rings stripped the threading already

Warne HyperLite Picatinny

Has anyone tried these rings out yet? Looking for general feedback after I was advised to steer clear of the Talley Ultralights. I'm buying a Tikka with an included Picatinny rail and these looked promising but I'm not finding any real user reviews anywhere...

rokslide.com

 

[nighthawkf-117]

Interesting issue and response from Warne

 

[SDHNTR]

OP, i’m just curious, is there any actual mechanical damage to your scope? Bound up erector? Or is that just some minor cosmetic damage to the finish, as it appears.

 

[Sundodger]

Guys, it doesn't change "the torque" the question to ask is if it changes the torque tension relationship.

Tension is what keeps hard joints together, torque is an imperfect proxy for tension.

In a previous life I was the lead engineer for bolted joints at an OEM manufacturing company, we did extensive testing with Loctite and to our surprised the compounds we tested had no statistically significant effect on the tq/tension relationship. Lock patches on the other hand, what a hot bag of steaming garbage those are...

 

[Wrench]

Jim Borden makes the short list of smartest men on earth regarding rifle actions. He's an engineer by trade and own one of the highest regarded actions made today.

Jim made some interesting comments about torque and wet threads that deserves a listen. You can skip ahead to about the 2 hour mark if you don't care to learn about borden.

 

[JohnDough]

Cases like this, I would look at the tool used to apply the torque.

Fat Wrench may have gone belly up.

I tested several of them. There was some error with each as I recall, but one was way off. It was repeatable but the value on the scale didn't match the torque applied. Another would not always click.

The only time I have seen tubes severely crushed was from a defective tool.

I have sometimes become suspicious. What I do is install the half inch and set torque and then crank on the crossbolt and get a "feel" for 15 in lb and assure myself it's clicking over, before I do tedious work with it.

 

[JohnDough]

Guys, it doesn't change "the torque" the question to ask is if it changes the torque tension relationship.

Tension is what keeps hard joints together, torque is an imperfect proxy for tension.

In a previous life I was the lead engineer for bolted joints at an OEM manufacturing company, we did extensive testing with Loctite and to our surprised the compounds we tested had no statistically significant effect on the tq/tension relationship. Lock patches on the other hand, what a hot bag of steaming garbage those are...

I've seen loctite modify tension/compression/stretch, and I've seen it not. I think substrate materials are also a factor here.

 

[4th_point]

I have sometimes become suspicious. What I do is install the half inch and set torque and then crank on the crossbolt and get a "feel" for 15 in lb and assure myself it's clicking over, before I do tedious work with it.

You can use the short end of a hex or Torx key. Most people are unlikely to over tighten a fastener with such a small portion to grab.

Once tight with the short end, simply snug it up with the long end. It helps some people develop a feel.

I have a calibrated beam type TW but I don't have any concerns using the method above.

 

[4th_point]

I've seen loctite modify tension/compression/stretch, and I've seen it not. I think substrate materials are also a factor here.

I believe you. That's why a formal study is supposed to be done, if any of the affects are critical.

Information from some adhesive manufacturers can be misleading. Loctite may still advertise that their locker doesn't affect "torque" but their technical papers stated that a study should be done with and without locker to ensure proper joint connection.

Most of this is unlikely to matter for hunters and shooters. However, as a group, I would just prefer that we don't regurgitate bad information with blanket statements.

 

[4th_point]

To stir the pot a bit, has anyone ever taken a fastener, applied thread locker without cleaning/degreasing, and had it fail to set or hold properly?

And can prove that lack of cleaning was the cause?

I never have, whether on firearms or machinery. The adhesive has always set up and held. Its a pain in the neck to remove the residue, even 242, when disassembled too!

I've been fortunate to see all sorts of assemblies made in person, in various industries, and across different regions and none of the manufacturers clean or degrease fasteners. I also get to see details on customer returns and have yet to come across issues where failure to clear or degrease is a root cause.

But there might be certain products or applications where it might matter. If so, I'd like to know.

 

[Wrench]

I posted a video by Jim Borden who I guarantee knows more about actions and screws than most of us combined. If you watch that.....it's puts so much of this banter to sleep. Spoiler alert, he didn't say fingernail polish is the magic bullet.

 

[JohnDough]

You can use the short end of a hex or Torx key. Most people are unlikely to over tighten a fastener with such a small portion to grab.

Once tight with the short end, simply snug it up with the long end. It helps some people develop a feel.

I have a calibrated beam type TW but I don't have any concerns using the method above.

I always use a torque tool. I could shred things with the shorter end of a hex, I'm willing to bet. Maybe I'll see how tight I can get something using just it and fingers, for science.

 

[Macintosh]

I posted a video by Jim Borden who I guarantee knows more about actions and screws than most of us combined. If you watch that.....it's puts so much of this banter to sleep. Spoiler alert, he didn't say fingernail polish is the magic bullet.

What did he say? I believe the section you were referring to was at 2:03:00 or so, he was talking about torquing barrels with regard to his displike for torque wrenches (one of the most imprecise tools in the hands of someone who isnt well-trained and hyper-vigilant about all of the minutia...or something along those lines), and he said something about a barrel torque wrench being accurate to within 1 or 2 lb out of 75, but used scope rings as an example of something that was easier to be imprecise, he mentioned something about 30-35 inlb, but I really did not understand the point he was making or what the implication was, other than it was easy to be imprecise using a torque wrench. I know what has worked for me, but I am also not formally trained in any of this stuff, so I'm curious what exactly your takeaway was?
Reading between the lines I believe you have some formal training in this sort of thing, and you have cited some engineering manuals and the like, but have been circumspect about your own actual procedure and rationale for it. How do YOU view threadlocker on scope ring screws? Do you use it? Do you consider it problematic or beneficial or inconsequential or ?? I'd be curious what your thoughts and experiences are and how you integrate it into your own SOP.

 

[Wrench]

What did he say? I believe the section you were referring to was at 2:03:00 or so, he was talking about torquing barrels with regard to his displike for torque wrenches (one of the most imprecise tools in the hands of someone who isnt well-trained and hyper-vigilant about all of the minutia...or something along those lines), and he said something about a barrel torque wrench being accurate to within 1 or 2 lb out of 75, but used scope rings as an example of something that was easier to be imprecise, he mentioned something about 30-35 inlb, but I really did not understand the point he was making or what the implication was, other than it was easy to be imprecise using a torque wrench. I know what has worked for me, but I am also not formally trained in any of this stuff, so I'm curious what exactly your takeaway was?
Reading between the lines I believe you have some formal training in this sort of thing, and you have cited some engineering manuals and the like, but have been circumspect about your own actual procedure and rationale for it. How do YOU view threadlocker on scope ring screws? Do you use it? Do you consider it problematic or beneficial or inconsequential or ?? I'd be curious what your thoughts and experiences are and how you integrate it into your own SOP.

I have a few in/# wrenches that include a beam style and break away. I don't use them on small diameter high pitch threads. I make my living doing precision mechanical and machining and I have found that I can see/feel when a fastener is at it's load. Many fasteners have a spec for a touch off or minimum torque followed by a travel distance.

A 6-48 screw is so easy to stretch that it can break before it's even tight to some folks.....but if you've spun a #0 or #2 tap....you learn how to read the fastener.....hard to explain.

I do use thread locking compound and mostly 242. I think about how it works, it's anaerobic and must create the environment for it to work. I can't say that I've ever had it not set up.

When you come on torque on your rings you can feel the ring kiss and the gap will go from moving. 021" per rev to not.....in a hurry. When I feel the kiss I know to pay attention. If there's multiple screws....it's even worse because we want to balance the load, but will almost always over torque in the process.

If a person really wants to find out how torque on small fasteners can get out of hand quickly, grab a thread gauge plate and torque some fasteners....but before you come to full value, measure the OAL of the screw and again as you add torque. The growth you see is stretch. That's where you gain the clamp....but not all materials play the same. A sako screw for their rings and one hawkins sends are VERY different materials.

 

[JohnDough]

I have a few in/# wrenches that include a beam style and break away. I don't use them on small diameter high pitch threads. I make my living doing precision mechanical and machining and I have found that I can see/feel when a fastener is at it's load. Many fasteners have a spec for a touch off or minimum torque followed by a travel distance.

A 6-48 screw is so easy to stretch that it can break before it's even tight to some folks.....but if you've spun a #0 or #2 tap....you learn how to read the fastener.....hard to explain.

I do use thread locking compound and mostly 242. I think about how it works, it's anaerobic and must create the environment for it to work. I can't say that I've ever had it not set up.

When you come on torque on your rings you can feel the ring kiss and the gap will go from moving. 021" per rev to not.....in a hurry. When I feel the kiss I know to pay attention. If there's multiple screws....it's even worse because we want to balance the load, but will almost always over torque in the process.

If a person really wants to find out how torque on small fasteners can get out of hand quickly, grab a thread gauge plate and torque some fasteners....but before you come to full value, measure the OAL of the screw and again as you add torque. The growth you see is stretch. That's where you gain the clamp....but not all materials play the same. A sako screw for their rings and one hawkins sends are VERY different materials.

See, with a scope, its not bolt stretch but mainly tube compression, and each scope compresses differently due to wall thickness, etc. A torque wrench is best here, unless you specifically only mount one make and model of scope, they all feel different to me.

 

[Wrench]

Tony Boyer's book has a very comprehensive explanation of scope mounting. If you don't know who he is, he's the best of the best in the world. He even has a chapter on scope pillar bedding.

 

[Wrench]

See, with a scope, its not bolt stretch but mainly tube compression, and each scope compresses differently due to wall thickness, etc. A torque wrench is best here, unless you specifically only mount one make and model of scope, they all feel different to me.

John, I mount an awful lot of scopes and haven't crushed a tube in at least 20 years. I figure if I can chamber a barrel and true up an action....mounting a scope should be within my capabilities.....but explaining it apparently isn't.

I love the internet.