Rifle Scopes carbon fiber MK IV ???

[7.62willdo]

Has anyone seen one of the knew carbon fiber bodied MK IV scopes i hear leupold is getting ready to come out with?
17% stronger 34% lighter?

 

[Shortdraw]

Re: carbon fiber MK IV ???

Haven't heard about them yet. Sounds like a good idea, I like carbon fiber stuff.

 

[ORD]

Re: carbon fiber MK IV ???

If this is more than just the "Internet Rumor Mill" running wild, I can't wait to see the price tag on this one. Mark 4 scopes are already getting overpriced for the features they offer (IMO) and lets face it...carbon fiber ain't exactly cheap! I don't know that CF is exactly cut out for use as a scope body either!!

 

[generalzip]

Re: carbon fiber MK IV ???

Interesting...While carbon fiber has its places I don't really feel a scope is a good application for it. Too brittle and too susceptible to creep and other deformation mechanisms. I guess it depends how thick they make it. Either way I'm really interested in seeing it if they do it.

 

[Powder_Burns]

Re: carbon fiber MK IV ???

Thats my impression of carbon fiber as well. Brittle, cracks, UV gets to it...not in a scope, unless they are doing something radically different.

 

[Shortdraw]

Re: carbon fiber MK IV ???

Carbon is plenty strong. It can be made a lot less brittle with the right resins. It is a lot more versatile than it used to be. UV is a big issue unless it's painted or coated. My best friends mother is the head of composites at a major aerospace company and makes me some very cool gifts. I get a CF goodie every year for my birthday and Christmas. We'll see if this pans out. Prices will be stupid I'm sure.

 

[generalzip]

Re: carbon fiber MK IV ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: mnshortdraw</div><div class="ubbcode-body">Carbon is plenty strong. It can be made a lot less brittle with the right resins. It is a lot more versatile than it used to be. UV is a big issue unless it's painted or coated. My best friends mother is the head of composites at a major aerospace company and makes me some very cool gifts. I get a CF goodie every year for my birthday and Christmas. We'll see if this pans out. Prices will be stupid I'm sure. </div></div>

It's not really about strength. Plenty of materials are very "strong." All this refers to is a high ultimate tensile strength. What's not taken into account when referring to strength is the common mechanisms of deformation and failure ie. crack growth. And amorphous(glassy) solid such as the resin in a composite is susceptible to other forms of deformation such as shear banding and crazing ahead of the crack tip. Also, the failure of glasses is brittle whereas it is ductile in metals. Also, the processing for a composite of this shape would be somewhat difficult to repeat consistently to the same tolerances because so much crap can vary with composites processing (bubbles, humidity, temp, proper mixing of system components, fiber alignment, etc.)

I'm a Material Science and Engineering major with a focus on composites at MIT so I'm not just pulling this out of my ass.

As for Leupold, I feel like whether it's made of CF or cow shit it will still be overpriced.

 

[Widowmaker0001]

Re: carbon fiber MK IV ???

Ok,guess I'll chime in....i was a type-3 composite engineer for 10 years.I know a thing or two about carbonfiber,kevlar or any laminate for that matter.I can create aerospace tolerence grade comosites.I build my molds from carbonfiber too(many ways to do it,but aerospace uses especially carbonfiber or CNCed aluminum for ALL molds to keep there tolerences through the cure cycle.There is a few ways to use carbon(the laminate)for product creation.In the case for a scope body,it is Very doable and can be produced at a very consistant ratio.I worked for Rockwell and then Boeing.There is formulation to keep each part the same,one,we weight the resin.(in the aerospace industry we only use a special epoxy which is 100% UV protected,handles 1750 degrees and has a .001 shrink ratio over 100 hundred years.Or we use Prepreg(pre-empregnated epoxy into Carbonfiber shipped to us in a freezer roll and we have to freeze it to keep it usable,cures at room temp,lol..Pretty much the amount of material depends on the part being created so these numbers will need to be duplicated...But I know that making cylinders is the issue,so they would use a mandrel style mold where the carbonfiber thread is "spun" around the mandrels shape of a scope body,from one end to another,then when the scope body is finished being formed on the mandrel mold,then it is put into an autoclave for an hour or two under 1000psi and 320degrees to cure the part.when cured,the interior mandrel mold is made to be disposable and is "broken out" of the new formed scope body and cleaned to spec.If there is to be threaded sections of the scope body integrated into the scope tube,they too can be integrated into the mold process.Point is:carbonfiber is just a material,molecularly speaking.a carbon atom when attached to another carbon atom has the most strength compared to any other atom to atom bond in science.That being said,just because you can lay carbonfiber up in a mold doesn't make it a strong or good part to say the least.Laminates are only as good as the engineer laying the laminates into the mold in the correct staggered degree patterns and direction,in uniformity and consistancy and then finally coming down to the laminate process used.Can u make a scope out of carbonfiber and make it good?,hell yeah but it is gonna cost a pretty penny and when the Leupold name ends up on there,well it probably is just going to go up.Just my .02cents and food for thought.goodshootin'



~Reagan

 

[generalzip]

Re: carbon fiber MK IV ???

As an engineer my concern isn't necessarily that it wouldn't work. It would be easy enough to build a single prototype and test it. From an engineering standpoint, using CF in a scope is complete overkill when Aluminum scope bodies have worked incredibly well over the years. My main concern with CF would be cracking. It is a brittle material and even the slightest crack would lead to Nitrogen leaking for the scope and humidity getting in. Not good.

To use the filament winding method as stated above would be absurd and a waste of time and money. These machines are incredibly slow (I've used one before) for producing mass quantities of anything. They are mainly used in the defense industry and aerospace industry for rocket and missile bodies and the like. My main point is simply that the processing methods, at least that I could fathom, would be absurdly intensive to make a scope.

Also, I've used prepreg at Army Research Labs at Aberdeen Proving Grounds, MD before but have never seen one cured at room temp. I'm sure it's possible, but every prepreg I've seen had to be autoclaved or in a press @ temp (usually around 250-400 F). What kind of pre-preg system did you use to cure at room temp? What was that laminate used for, if you are allowed to tell me?

 

[Widowmaker0001]

Re: carbon fiber MK IV ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: generalzip</div><div class="ubbcode-body">As an engineer my concern isn't necessarily that it wouldn't work. It would be easy enough to build a single prototype and test it. From an engineering standpoint, using CF in a scope is complete overkill when Aluminum scope bodies have worked incredibly well over the years. My main concern with CF would be cracking. It is a brittle material and even the slightest crack would lead to Nitrogen leaking for the scope and humidity getting in. Not good.

To use the filament winding method as stated above would be absurd and a waste of time and money. These machines are incredibly slow (I've used one before) for producing mass quantities of anything. They are mainly used in the defense industry and aerospace industry for rocket and missile bodies and the like. My main point is simply that the processing methods, at least that I could fathom, would be absurdly intensive to make a scope.

Also, I've used prepreg at Army Research Labs at Aberdeen Proving Grounds, MD before but have never seen one cured at room temp. I'm sure it's possible, but every prepreg I've seen had to be autoclaved or in a press @ temp (usually around 250-400 F). What kind of pre-preg system did you use to cure at room temp? What was that laminate used for, if you are allowed to tell me? </div></div>

Hey General~Actually that prepreg was used for formula atlantic exhaust cutouts,lol.but i hear you,i was basically staing it "could" be done without a doubt.Filment winding machines aren't identical either.The laminate processes and expoxies used at Boeing are Patented BTW and have been that way for a while.The machines used over their are the same,alot of them are custom rigs designed by composite engineers to create faster more consistant ways for laminating and winding.Yes,i've laid up rockets/missles and also alot more secretive and one-off protypes for third party/government use.Cracking??have you chececked out bicycle frames and the such.They mostly use wound filament technology.They've been using crazy clamps with crude amounts of force for seat posts and handle bars,so it can be made easily to withstand clamping and recoil pressures.IMHO though,i wouldn't make a scope tube out of carbon/kevlar.I believe as far as manufacturing is concerned it is too costly and time consuming to do this without alot of extra cost directly paid for by the consumer.The "tried & true" metal scope bodies have been doing quite well,for a while.saving for my USO matter o' fact,lol.Just my .02 cents.Goodshootin'

~Reagan

 

[generalzip]

Re: carbon fiber MK IV ???

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Widowmaker0001</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: generalzip</div><div class="ubbcode-body">As an engineer my concern isn't necessarily that it wouldn't work. It would be easy enough to build a single prototype and test it. From an engineering standpoint, using CF in a scope is complete overkill when Aluminum scope bodies have worked incredibly well over the years. My main concern with CF would be cracking. It is a brittle material and even the slightest crack would lead to Nitrogen leaking for the scope and humidity getting in. Not good.

To use the filament winding method as stated above would be absurd and a waste of time and money. These machines are incredibly slow (I've used one before) for producing mass quantities of anything. They are mainly used in the defense industry and aerospace industry for rocket and missile bodies and the like. My main point is simply that the processing methods, at least that I could fathom, would be absurdly intensive to make a scope.

Also, I've used prepreg at Army Research Labs at Aberdeen Proving Grounds, MD before but have never seen one cured at room temp. I'm sure it's possible, but every prepreg I've seen had to be autoclaved or in a press @ temp (usually around 250-400 F). What kind of pre-preg system did you use to cure at room temp? What was that laminate used for, if you are allowed to tell me? </div></div>

Hey General~Actually that prepreg was used for formula atlantic exhaust cutouts,lol.but i hear you,i was basically staing it "could" be done without a doubt.Filment winding machines aren't identical either.The laminate processes and expoxies used at Boeing are Patented BTW and have been that way for a while.The machines used over their are the same,alot of them are custom rigs designed by composite engineers to create faster more consistant ways for laminating and winding.Yes,i've laid up rockets/missles and also alot more secretive and one-off protypes for third party/government use.Cracking??have you chececked out bicycle frames and the such.They mostly use wound filament technology.They've been using crazy clamps with crude amounts of force for seat posts and handle bars,so it can be made easily to withstand clamping and recoil pressures.IMHO though,i wouldn't make a scope tube out of carbon/kevlar.I believe as far as manufacturing is concerned it is too costly and time consuming to do this without alot of extra cost directly paid for by the consumer.The "tried & true" metal scope bodies have been doing quite well,for a while.saving for my USO matter o' fact,lol.Just my .02 cents.Goodshootin'

~Reagan </div></div>

Wow that's pretty interesting. In regards to cracking what I was referring to was steady state crack growth due to static and cyclic fatigue. Of course the individual fibers present a huge obstacle to crack growth (one of the many reasons CF and other composites are so strong and tough), but a near microscopic crack can amount to a problem when a scope is under pressure. This could cause Nitrogen to leak out and humidity to go in over a long enough time. Obviously, something like a bike frame wouldn't matter because its not under pressure. It would also depend how thick they made the walls of the scope. This would make an interesting little project to do in SolidWorks or some other stress analysis program. I have no clue how much pressure an average scope is under, but I know there would be some cyclic fatigue occurring particularly around the scope rings on each shot.

PS good to see fellow engineers especially composites engineers on the forum. It's amazing how long composites have been around and how long it has taken for people to realize how awesome they are and how much room for improvement there is.

 

[jeo556]

Re: carbon fiber MK IV ???

If this is true it sounds like an answer to a question that nobody asked.

Merry CHRISTmas all.