Threaded K Baffle Monocore

[TheMissingLeg]

Interesting concept. Some questions if you don't mind:

1) How much torque do you put in your Caps to archive your desired "tension" ?. I understand it's not too much since you just have a knurled surface in the Caps.
2) Since you are stressing the Metal, how did you calculate the incoming forces (due to gas pressure) ?. So you can add to your "tension" torque and then see how close you are to a elastic deformation (not permanent but could take the yield point down dramatically and, consequently, the tensile strength).
3) Don't you think the natural elastic micro deformations (due to heat) are incompatible with having a stressed solid ?. You said you shot lots of consecutive rounds so it should be really hot there.
4) Aren't you afraid to damage the threads due to torque ?. Your threading Pitch and Major diameter looks like very small in your Pics.
5) Have you considered Y deformations due to X torque ?. Your solid (K-Baffle) is not mass symmetric mainly due to the Mouse Hole.
6) Do you use CNC boxes to Machine the Baffles ?
7) How do you 100% seal the threading surfaces so zero gas (shot) gets in ?. O-Rings ?.
VIII) (Note: i did use the number 8 for this question but showed an icon). What are your max./min. tolerances for Manufacturing ?. Also ID/OD design clearance.
9) Could you please develop a little bit more your Blast design (the large threaded spacer) ?. You say there is no FRP but the Blast looks quite large in the Pics.
10) Your Can is 1.25 OD and most Manufacturers go to 1 inch. Why 1.25 ?
11) Why K-Baffles trend to bend (as you said) ?

I'm still trying to digest your concept so sorry for the mag dump. If you can share with us your calculations, I do really appreciate that.

Sorry, just forgot two questions:

1) How do you deal with the Recoil Booster in the 9 mm and the 45 Cans ?. I understand you are using the same concept.
2) Isn't it easier, cheaper and faster to build the first couple of Baffles (the most critical) in SS and weld them together with the Rear Cap (having it the Blast) ?. Mostly thinking on larger Calibers than .22LR.

[gunny50]

"TheMissingLeg"

1st welcome
2nd where are you located?
3rd what did you study? ( in remark you tour technical questions)
4th what are your machining skills?
5th did you ever build F1 cans and if so for what calibers? ( monocore in the picure is yours? what caliber ? Could you post specs there?)

I know its a long list of questions, BUT it is so I know what we can expect from you

Not my product but I thought lets go ahead and give some pointers.
its not my intention to be rude or so.

Wow that is a lot go questions, why do you not ask for the drawings
3- the design shown is for 22
4- with the 7068 material he uses you can go 1mm pitch or smaller, no problem also if you hard coat… no issue there
6 - CNC boxes? do you refer to CNC machines?
7- he mentioned that he was using an angled surface to seal the gas out of the connecting threads - please read back all information he gave.
8- see the drawing remark on top
9- blast seems big to me as well, BUT we do not know how deep his connectors fall inside the blast-baffle
10- in us 1" is used a lot in EU 30mm is used a lot.
As long as open sights can be used volume will help and you just need to keep an eye on blast baffle space and volume too prevent FRP.
11- bending K's is also depending on several facts - material used, outer contour, blast-face angles, radiuses used on the product etc etc. not that simple to say they bend..
12- that is easy, if you have ever build a booster you know how to incorporate one in a design like this, you can easily incorporate it to be part of the tensioned inner core and hold the tube between booster and end-cap seal with vithon O-Rings and be done with it.
13- sure SS- 400 series - 17/4 - 316 with the right coating would help , but for 22 you want to be able to take it apart for cleaning so welding is not an option.

For large calibers you could weld But you would need the right equipment, check for warping, calculate for shrinkage of the core, have extra machining steps.
As he's a manufacturer and not only making one F1 can, that is a lot more steps to take with same end product so more costly to do, resulting in more expensive product and in most cases smaller sales..
For a form 1 in large caliber it might be an option, but I do not think most F1 builders would go that route.

Gunny

[TheMissingLeg]

I fully understand. My fault, sorry, too many questions for a first or second Post here.

I'll introduce myself: My name is Kevin and I'm a Mechanical Engineering student (still one year+ to go). I'm located in USA (Oregon) and my family is mostly composed of Irish immigrants. My Father, Uncle and Brother own medium size Machine Shops in USA and China (not 100% Gun related, mostly Automotive, Aerospace and Medical).

I'm fully aware of Suppressor legalities in US but having two 02/07 licenses at Home, i don't really pay much attention to that. We all enjoy Hunting and Shooting and do Suppressors as a Hobby. I understand F1 limitations.

My skills are mostly based on what i have learned at Home and now at College. With help from the Family, i have designed and built several Cans, from .22 to .338 for Rifles and 9, 45, 40 and the small ones for Pistols. I have also made mods for several Guns to be more Suppressor friendly, including a 1911 one to skip the need for a Recoil Booster (ongoing project with a new QDM). Finally, I'm fascinated with Muzzle Devices like Flash Hiders, brakes, POIs, QD Mounts (I love them), ...

With regards to the processes, for CAD, i'm good at SolidWorks and super+ at Inventor (sorry, it's what my Guys got at the Shops). For CAM, i'm good in Mastercam and still on the go with Camworks (some basic knowledge of Solidedge and others). For Simulations, I'm just average with Mechanical Simulation and still learning others so i can't say too much (i can only share frustration)

So, i think my professional career is already drawn. Guns are what i mostly like.

I'm an avid learner (sometimes hungry) but next time I'll take it easy and won't push that hard. So, my intro is here. Please forget my previous Post and just give me an answer (if you are so kind):

Why K-Baffles under tension are stronger ?

Thanks for your understanding.

PS: I asked about tolerance and/or clearances just to find out how tight (and sealed) the system is in order to prevent heat, gas and carbon buildup leaks inside the most critical junctions, not tryng to get Drawings. The Can shown in my avatar is a multi-mount, multi-device MonoCore for my 300. Made out of SS 304L (Tube and Rear Cap frame) and Alu 7068 (Core and Front Cap). It's 10.5 inches long x 1.75 OD and overall walling (varies) is 0.1. Blast is protected either with the Muzzle Device or when using as thread on with a SS spacer. All metals are treated but don't know how.

[Bendersquint]

How did you get the permission from SoundTech to use their patent?

[TheMissingLeg]

Are you talking to me or to OP ?, if it's to me, please, provide Patent number and I'll check.

[Bendersquint]

Are you talking to me or to OP ?, if it's to me, please, provide Patent number and I'll check.

Yes, talking to you, and if you have to ask the patent number you definitely didn't ask for permission to use their patent.

I would suggest you change your picture and not post it, lawyers love that stuff!

[TheMissingLeg]

I'm asking you for the number (or legal owner) because i couldn't find anything related to "SoundTech" and firearm silencers in our Archives. My Father usually takes care of all this stuff (due to his regular business) and i have to ask with some precise information. In a quick look (googleing Patents) i couldn't find anything equal just similar designs (with regards to the slanted walls). I didn't read the full claims but for sure the double angled Baffles (or Y flipped) feature is not present and that makes a huge difference (among other features like angled ports, two stages blast, multi-mount system, rotation brakes, ... ).

[Bendersquint]

I'm asking you for the number (or legal owner) because i couldn't find anything related to "SoundTech" and firearm silencers in our Archives. My Father usually takes care of all this stuff (due to his regular business) and i have to ask with some precise information. In a quick look (googleing Patents) i couldn't find anything equal just similar designs (with regards to the slanted walls). I didn't read the full claims but for sure the double angled Baffles (or Y flipped) feature is not present and that makes a huge difference (among other features like angled ports, two stages blast, multi-mount system, rotation brakes, ... ).

I can tell you I am 99/9999998% certain you don't have the permission since its solely licensed right now.

The violation I am seeing is the slant baffles, even if you have other things that are different the slant baffles still sink you.

Here is one of the patents from SoundTech, there are several.

http://www.google.com/patents/US7073426

[TheMissingLeg]

Ah !, ok, I've seen this one. They have 7 claims (and several add-ons) and we have detected 13 differences (one per claim plus some others). All of them are directly related to the Patent, not to the accessory features. It's quite difficult to see the differences into an Avatar picture. In any case, i understand you are the Patent owner so feel free to contact me if you want any further clarification (my e-mail should be in my Profile. If not let me know and I'll make it public).

Now, can we get back to the original Post ?, I'd like to learn more about this threaded K-Baffles, i would like to have a little development on why K-Baffles are stronger under tension.

[curtistactical]

Interesting concept. Some questions if you don't mind:

1) How much torque do you put in your Caps to archive your desired "tension" ?. I understand it's not too much since you just have a knurled surface in the Caps.
2) Since you are stressing the Metal, how did you calculate the incoming forces (due to gas pressure) ?. So you can add to your "tension" torque and then see how close you are to a elastic deformation (not permanent but could take the yield point down dramatically and, consequently, the tensile strength).
3) Don't you think the natural elastic micro deformations (due to heat) are incompatible with having a stressed solid ?. You said you shot lots of consecutive rounds so it should be really hot there.
4) Aren't you afraid to damage the threads due to torque ?. Your threading Pitch and Major diameter looks like very small in your Pics.
5) Have you considered Y deformations due to X torque ?. Your solid (K-Baffle) is not mass symmetric mainly due to the Mouse Hole.
6) Do you use CNC boxes to Machine the Baffles ?
7) How do you 100% seal the threading surfaces so zero gas (shot) gets in ?. O-Rings ?.
VIII) (Note: i did use the number 8 for this question but showed an icon). What are your max./min. tolerances for Manufacturing ?. Also ID/OD design clearance.
9) Could you please develop a little bit more your Blast design (the large threaded spacer) ?. You say there is no FRP but the Blast looks quite large in the Pics.
10) Your Can is 1.25 OD and most Manufacturers go to 1 inch. Why 1.25 ?
11) Why K-Baffles trend to bend (as you said) ?

I'm still trying to digest your concept so sorry for the mag dump. If you can share with us your calculations, I do really appreciate that.

Sorry, just forgot two questions:

1) How do you deal with the Recoil Booster in the 9 mm and the 45 Cans ?. I understand you are using the same concept.
2) Isn't it easier, cheaper and faster to build the first couple of Baffles (the most critical) in SS and weld them together with the Rear Cap (having it the Blast) ?. Mostly thinking on larger Calibers than .22LR.

I will answer your questions in the order you ask them
1)Initially they are just hand tightened, pretty much the same thing you would do with a standard can but instead of squishing the baffles together you are pulling apart on them.

2)They don't have to be torqued that tight at all, when the gas pressurizes inside the baffles the threads will retain the baffles.

3)Not sure I really understand this one but here goes, it does get really hot and the material naturally grows when that happens but think about your standard silencer, the thin tube just above the blast chamber is threaded usually leaving only about a .030 wall thickness at best, on my design you have double the wall thickness at the threaded areas.

4)The threads are 1"-32 on the 1.25" cans and 1.25"-32 on the 1.5" cans, no your not going to hurt the threads by torqueing them, finer threads are by far stronger than course threads, there is way more surface area.

5)They don't get torqued tight enough to deform anything.

6)Yes I have cnc machines that the parts are ran on and I have been machining for 21 years I could do them just as good on manual machines it would just take longer.

7)O-rings are a joke in suppressors, I machine a 30deg (60 deg included angle) at the back of the threads that seals against the inside taper of the K-baffle, after 500rds on 22lr the threads are still clean when I disassemble the suppressor.

(sorry I am American not roman) the threads are class 2a and 2b as per the machinist handbook, the O.D. of the baffles is held .003 below the I.D. of the tube with a tolerance of +0 -.005 so at worst case there could be .008 clearance, doesn't seem to make that much of a difference except ease of disassembly.

9)The blast chamber does look long, notice even the blast baffle is 7068 aluminum, there is a .312 wall inside the blast chamber, my thought is lighter weight and on rimfires and handguns with that wall thickness there is no need for a stainless blast baffle.

10)My newest rimfire cans are 1" O.D. the reason for 1.25" was the use on 17hmr and 22mag but I do offer a smaller 1"x5" rimfire can, just more choices the 1.25" work great on the magnum.

11)The back flange of the K-baffle will eventually bend forward under heat and pressure because nothing is there to support it, on my baffle the thread retains the flange in position that's the most important aspect of threading them together, this is the reason a lot of people don't use them on centerfire rifles, its not because they are not quiet enough its because they are not strong enough, mine work fine on centerfire rifles.

12)My cans are light enough they don't need the booster, that's the reason for the aluminum baffles with extra wall thickness, the only stainless part on the rimfires and handgun cans is the end cap and it is 17-4ph with minimum wall thickness.

13)This kind of goes back to the previous answer but I made these as light as possible so as to not need a booster and welding them together would go against my idea of serviceability, I could weld all my cans but a lot of companies already do that, I like the idea of being able to disassemble the suppressors for cleaning and for handguns and rimfires theres no need for stainless baffles, I give a lifetime warranty on my baffles against failure do to use, I do not warranty somebody screwing the threads up or purposefully hurting them, but if you burn one out Ill replace the baffles free of charge.

[Bendersquint]

11)The back flange of the K-baffle will eventually bend forward under heat and pressure because nothing is there to support it, on my baffle the thread retains the flange in position that's the most important aspect of threading them together, this is the reason a lot of people don't use them on centerfire rifles, its not because they are not quiet enough its because they are not strong enough, mine work fine on centerfire rifles.

Can you please post some examples of the K baffles bending as described?

I have seen thousands of K baffles(some possibly older than you) and none have exhibited this, even on baffles that are remarkably thinner than your pictures K's.

[Bendersquint]

Ah !, ok, I've seen this one. They have 7 claims (and several add-ons) and we have detected 13 differences (one per claim plus some others). All of them are directly related to the Patent, not to the accessory features. It's quite difficult to see the differences into an Avatar picture. In any case, i understand you are the Patent owner so feel free to contact me if you want any further clarification (my e-mail should be in my Profile. If not let me know and I'll make it public).

Now, can we get back to the original Post ?, I'd like to learn more about this threaded K-Baffles, i would like to have a little development on why K-Baffles are stronger under tension.

Sorry, not the patent owner.

[curtistactical]

11)The back flange of the K-baffle will eventually bend forward under heat and pressure because nothing is there to support it, on my baffle the thread retains the flange in position that's the most important aspect of threading them together, this is the reason a lot of people don't use them on centerfire rifles, its not because they are not quiet enough its because they are not strong enough, mine work fine on centerfire rifles.

Can you please post some examples of the K baffles bending as described?

I have seen thousands of K baffles(some possibly older than you) and none have exhibited this, even on baffles that are remarkably thinner than your pictures K's.

Its not enough to see in photos, I have some out of a friends can I rebaffled, the first three baffles are convex on the rear face of the baffles probably .02-.03 but the front ones are flat, I measured this on a surface plate with an indicator, these are the only examples I actually have but its kind of interesting.

[TheMissingLeg]

Curtis, thanks a lot for your detailed explanations. Looks like a brilliant idea even if the theory (and in theory by now) it's not on your side. Congratulations and sorry for the short hijack of your Post.

I'll try to model some mechanical and stress simulations. If i make it, I'll share with you the results (your site's e-mail is fine ?).

[Bendersquint]

11)The back flange of the K-baffle will eventually bend forward under heat and pressure because nothing is there to support it, on my baffle the thread retains the flange in position that's the most important aspect of threading them together, this is the reason a lot of people don't use them on centerfire rifles, its not because they are not quiet enough its because they are not strong enough, mine work fine on centerfire rifles.

Can you please post some examples of the K baffles bending as described?

I have seen thousands of K baffles(some possibly older than you) and none have exhibited this, even on baffles that are remarkably thinner than your pictures K's.

Its not enough to see in photos, I have some out of a friends can I rebaffled, the first three baffles are convex on the rear face of the baffles probably .02-.03 but the front ones are flat, I measured this on a surface plate with an indicator, these are the only examples I actually have but its kind of interesting.

I would be interested in looking at them.

A properly designed K can take several tons of pressure. I have tried crushing them and its hard unless the fabricator doesn't know how to design them then its easy. I am guessing that is the case for the ones you have.

By your statement you were using it as a selling point, which is why I asked.

[curtistactical]

I would be interested in looking at them.

A properly designed K can take several tons of pressure. I have tried crushing them and its hard unless the fabricator doesn't know how to design them then its easy. I am guessing that is the case for the ones you have.

By your statement you were using it as a selling point, which is why I asked.[/quote]
Those were the only ones I have personally witnessed and yes they are only about .025 at the thinnest point and we had them on the saw it seems to be a pretty good test for silencers.

[curtistactical]

Curtis, thanks a lot for your detailed explanations. Looks like a brilliant idea even if the theory (and in theory by now) it's not on your side. Congratulations and sorry for the short hijack of your Post.

I'll try to model some mechanical and stress simulations. If i make it, I'll share with you the results (your site's e-mail is fine ?).

Sure that would be cool and much appreciated I look forward to hearing from you.

[Historian]

I'm asking you for the number (or legal owner) because i couldn't find anything related to "SoundTech" and firearm silencers in our Archives. My Father usually takes care of all this stuff (due to his regular business) and i have to ask with some precise information. In a quick look (googleing Patents) i couldn't find anything equal just similar designs (with regards to the slanted walls). I didn't read the full claims but for sure the double angled Baffles (or Y flipped) feature is not present and that makes a huge difference (among other features like angled ports, two stages blast, multi-mount system, rotation brakes, ... ).

I can tell you I am 99/9999998% certain you don't have the permission since its solely licensed right now.

The violation I am seeing is the slant baffles, even if you have other things that are different the slant baffles still sink you.

Here is one of the patents from SoundTech, there are several.

http://www.google.com/patents/US7073426

Thank you for these data that will be added to the archives.

I am surprised that a patent was awarded for the slant baffles. In the
'60s ( OCONUS. ) in the folklore were a few 'one-of-a-kind' slants cut and tried.

For example a 1.25" x 8.5" aluminum can had spacers made by cutting a tube with its I.D.
at 45º. The baffles then were made from round stock by first drilling out the
appropriate diameter .45 hole and then sliding it along a chop saw set up ...
cutting out 'salami slices' with the elliptical holes shown in the patent. Fast and dirty.

The pieces obviously could be assembled in only one way.
Open field testing gave no better results than straight
spacers and metal disks ... to the naked ears. Probably still rotting
in the undergrowth.

Oh, well. Everything gets reinvented.
As a French writer once said: " plus ça change, plus c'est la même chose ".

[gunny50]

http://www.google.com/patents/US7073426

Thank you for these data that will be added to the archives.
I am surprised that a patent was awarded for the slant baffles. In the
'60s ( OCONUS. ) in the folklore were a few 'one-of-a-kind' slants cut and tried.
For example a 1.25" x 8.5" aluminum can had spacers made by cutting a tube with its I.D. at 45º. The baffles then were made from round stock by first drilling out the
appropriate diameter .45 hole and then sliding it along a chop saw set up ...cutting out 'salami slices' with the elliptical holes shown in the patent. Fast and dirty.
The pieces obviously could be assembled in only one way. Open field testing gave no better results than straight
spacers and metal disks ... to the naked ears. Probably still rotting in the undergrowth.
Oh, well. Everything gets reinvented. As a French writer once said: " plus ça change, plus c'est la même chose ".

Happens all the time that patents are awarded on technology that is not new.

Take the FN / Charles Moore patents for silencer and also QD mount. US8490535
the bal bearing mount was used in 95 in trials in NL by military , I know as I delivered.
I was competing with Knights and see what happens years later… a ball bearing QD made by? yep Knights. and now a patent granted to FN??
also the baffles in this FN design are not new being partial flats - first patent as far as I can find US4459895 A by Mazzanti had half flats, -
The FN design (more than half but less that full) was already used in RUSIA (info can be found on russian websites about silencers as well) early 2000.
I have seen a silencer with baffles like this in Police files (taken from criminals, they mass produced these) in around 98 when I was visiting a customs office in Germany for purchasing MP5 and MP5K's.

Gunny

Edit - patent number and info

[Grounded]

http://www.google.com/patents/US7073426

Thank you for these data that will be added to the archives.
I am surprised that a patent was awarded for the slant baffles. In the
'60s ( OCONUS. ) in the folklore were a few 'one-of-a-kind' slants cut and tried.
For example a 1.25" x 8.5" aluminum can had spacers made by cutting a tube with its I.D. at 45º. The baffles then were made from round stock by first drilling out the
appropriate diameter .45 hole and then sliding it along a chop saw set up ...cutting out 'salami slices' with the elliptical holes shown in the patent. Fast and dirty.
The pieces obviously could be assembled in only one way. Open field testing gave no better results than straight
spacers and metal disks ... to the naked ears. Probably still rotting in the undergrowth.
Oh, well. Everything gets reinvented. As a French writer once said: " plus ça change, plus c'est la même chose ".

Happens all the time that patents are awarded on technology that is not new.

Take the FN / Charles Moore patents for silencer and also QD mount. US8490535
the bal bearing mount was used in 95 in trials in NL by military , I know as I delivered.
I was competing with Knights and see what happens years later… a ball bearing QD made by? yep Knights. and now a patent granted to FN??
also the baffles in this FN design are not new being partial flats - first patent as far as I can find US4459895 A by Mazzanti had half flats, -
The FN design (more than half but less that full) was already used in RUSIA (info can be found on russian websites about silencers as well) early 2000.
I have seen a silencer with baffles like this in Police files (taken from criminals, they mass produced these) in around 98 when I was visiting a customs office in Germany for purchasing MP5 and MP5K's.

Gunny

Edit - patent number and info

My predecessor had his hand in that design.

[Bendersquint]

My predecessor had his hand in that design.

Very good to know that you didn't create that design.

[gunny50]

"Grounded"
My predecessor had his hand in that design

in the FN design?

Gunny

[Grounded]

"Grounded"
My predecessor had his hand in that design

in the FN design?

Gunny

Yes, even though we don't have anything commercially out....yet... we have been working on development for 5-6 years. Our thing was always expertise in fluid dynamics so a fair amount of time was spent characterizing the blast waves.

[calinb]

Can you please post some examples of the K baffles bending as described?

Link>>> Watched a can get ruined.

The wall is certainly thin where it failed, but keeping the baffles in tension might permit a thinner and lighter baffle stack than one that is held in compression between end caps. Seems like the concept merits an FEA workup to me.

Didn't PaulNoiseLess do one of these screw-together mono cores (or at least suggest one)?