Absolutely awesome work. This thread could possibly sell a few more URX's based on how easy you made it look. You need to get this moved to the new KAC Industry Forum if it isn't there yet.

Ok..  I got a Sabre 24" benchrest upper with the heavy stainless bull barrel. I just picked up a URX II rifle length from the EE.
I didn't know what I was getting into and thought it was a simple gig installing the rail. What's the story with the barrel nut wrench? IS there one floating around for us guys to use..  Kind of like the honor/ buddy system ? I will pay to get my hands on one !

The one I made is currently KIA, though I'm working on using an EDM or maybe trying to investment cast another one.



You are going to need to buy a new barrel nut from KAC as they are one time use nuts.



 

I got a new rail kit so the nut is new. This is the upper I plan on using...I don't think I should have any problems with the install other than the nut wrench. ??

http://www.sabredefence.com/products.php#products/heavyBench

Bump for updates

The plan is to attempt lost wax casting one in the coming days. Pics to follow.



 

Just read through the entire post...very nice. My hat goes off to you sir on job well done.

Why is everyone so upset about the lock tight thing? Blue Locktite works very well as long as you apply it correctly.
For a moment, think about something more critical to us all, how about something that all of our loved ones use everyday....a car. How are those wheels held in place? Torque. Do you locktite your wheel nuts...doubt it.

Look forward to seeing all the pics when I get home...images are blocked on my work PC

Bump.  Any new news?  I, along with many others,  would be interested in renting/buying a cheaper version.

Double tap.

All I can say is WOW!

A bit late, but I have to say great job.
I have the will and some of the CAD tools, but not the machines.  

Updates coming in the coming weeks.

Wow great work on the wrench, I'm looking forward to updates.  Just wondering, did you have any plans to sell or rent these out in the future?  My only complain with the URX rail is the fact that I can't work on my upper myself,  if there was an affordable wrench I would buy one in an instant.

Awsome thread, man.  Thanks for sharing with us.

I see something on the horizon!!! Hold on too that thought!

Mark

Awesome work.  I would love to have the skills and tools you have at your disposal.

This thread brings back memories of FSAE  machining in school.

Great work OP!

So here's the scoop.
I got a bit tied up last spring with collegiate rowing, so I never got
around to CNC machining a wrench. In the coming weeks it is my plan to
document everything necessary to machine a functional wrench from a
billet of tool steel, including tool selection, all the CNC programming,
setting up a CNC mill, possible sinker EDM shenanigans, etc.
My motivation for taking this is a step further stems from me applying for a Manufacturing Engineering position at Knights this fall, which I might add still apparently is open. I was rather pissed to receive this one my birthday:





So now, since they aren't going to hire me, I really don't mind stepping on any toes. So I thought I'd put that five years of Manufacturing Engineering and Engineering Entrepreneurship education to use and flex my wings.
The first order of business was to tweak my CAD models of the part and
since I somehow managed to delete my CAD files from last time, I had to
start from scratch this afternoon
I will still most likely need to tweak them a bit to get the fit I want
on the barrel nut. So to check it, I'm either going to need to tear my
SBR apart or order a new nut to use as reference material.
Here's the new CAD model version 1.0.





Here are the subsequent rapid prototyping models. You may noticed that they look a bit different than the last RP models I made. Since then we upgraded and purchased another machine for our shop that utilizes a newer RP material called ABS Plus, which is an optimized material,, much like regular old ABS but has characteristics that allow you to create a lot stronger RP models.


 

 

I love machining threads.

From page 1 - $260 for a damn wrench??????

I'd be machining one also.

Sorry to hear you didn't get the job.

Since I have some time today, I did some more revisions to the wrench CAD model. I noticed when I tested the fit of the RP model on a barrel nut that there was a little play, so a few adjustments had to be made.
Since there was some play in the teeth and that I knew the teeth were correctly sized, I knew that the spacing was a bit off and that they need moved inward. The center of the teeth were originally about 0.650 from the centerline of the wrench, and I moved them into 0.645 which isn't exactly a lot, but since it's an aluminum nut, you want maximum grip so you don't booger the darn thing up.

The next thing I addressed is what we Industrial engineers like to refer to as DFM, which is design for manufacturing, basically it's looking at a part and making it as easy as possible to manufacture and still retain all of it's original design purposes. In this case, since I don't want to pump a bunch of money into this and buy 10 different carbide end mill (which are quite pricey) I wanted to be able to be able to maintain all the important geometry and be able to machine it with as few end mills as possible. Another thing that comes into play if I was doing a huge production run of these would be time. If I'm running ten different tools, they take a decent amount of time to load in the CNC and get zeroed out and time costs money, so all this needs to be kept at a minimum.
The way I have it modeled, I should be able to get away with three end mills. a 1/16" for the teeth and square, a 3/8" for the profile, and a 3/8" ball for the one fillet that bridges the body of the wrench and the arm portion.






So I'll run another rapid prototype and in about 45 minutes I'll check to see whether my changes helped.




 
 

Unclemoak,

As much as I want a cheaper wrench, I also like the educational parts you throw in. Keep it up Mate!

Mark

unclemoak, you have my business if you put this wrench into production. My upper should be coming back on Tuesday from California, had it shipped to have the URX II installed. I can do the install, but spending nearly $600 on tools I'll most likely only use once is .

However, I realize it's becoming more important that I have tools so I can maintain my own weapons. So, if this wrench of yours is reasonably priced, I'll be sure to purchase one from you.

MAKE. THIS. HAPPEN.... PLEASE!!!

Awesome, job.  I love the drawings and looking at the manufacturability (is that a word?) of the part.  I am out of manufacturing now, and I miss the job where I had access to a machine shop.  It would make working on guns so nice.  

Manufacturability
is a word in common usage in the manufacturing industry, though I don't think Webster recognizes it. I was reading through a case study this fall that dealt with design challenges in the Boeing 787 Dreamliner and remember reading that initially like 5% of the door hardware was the same on all the cabin doors on the plane, management made the designers sit down and figure out how to make them more identical. After like 6 weeks, designers were able to figure out how to use 95% identical hardware on all the exterior doors on the plane.
Here's my revised model that I got done with yesterday. I tried to post an update last night, but the servers were down or something






This wrench fits perfectly on the nut , so any improvements from here will be to help DFM or to make the wrench more robust.
I took the old model (gray) and overlaid it with the revised version (purple). You can see the areas were some changes have been made.



The purple/gray crosshatched areas are essentially the same geometry,
Solidworks has a hard time differentiating them, hence the cross hatch.

I changed all the major fillets to 3/16' radius so they could all be machined with a 3/8" dia cutter simply because I have a whole drawer of them.







Here you can see how the teeth were moved inward the 0.005" that I mentioned earlier.










 

I made an attempt to figure out the whole CAM thing this afternoon



After about 6 hours, I decided to call it quits for the day. I'll post some pictures tomorrow morning and write up an explanation of how you program the toolpaths for the CNC.

man is that ever slick.....I missed my calling going into the LE world...much much rather be doing manufacturing....oh well I guess that is what retirement is for.

Mark

Just read through the whole thing and I just wanted to say it was very informative. Thanks for taking your time to post all of this.

Okay, here's some of the Master CAM work that I did on Monday.
Basically after you develop your 3D model or CAD model, you need to program all the tool paths, so the CNC machine knows where it needs to put the cutter and how fast to spin it and all that jazz. To do that you need a CAM software package. In this case, I'm using a program called MasterCAM X4, which is a pretty popular program for this type of work. This program will take your programmed tool paths and write them in a language called G Code which the CNC machine can interpret as movements, tool changes, etc.
The first step was saving my Solidworks file as an .IGES, which is a universal 3D modeling file extensions that can be read by many different CAD/CAM software packages. After that, I opened the file in MasterCAM as you can see it is the green wire frame in the picture and the surrounding red box is the roughly the size of billet of tool steel I'm going to use. When setting up the size of the billet you are using, you can also input what kind of material you are using then MasterCAM will populate all your feed and speed rates, granted they aren't the best estimations, so I'll most likely have to change them later.

Next comes programming all the tool paths. For this you can select all sorts of operations like pocketing, contouring, drill, facing, etc. The first thing I programmed was the basic contour of the part. So I selected the contour I wanted, which was the outline of the whole part, then selected the contour feature, then you can input all sorts of variables like how deep of a cut the machine will make with each pass, how many passes, etc. I chose to use a 3/8" flat endmill and to make ramped style passes. I like to use ramped passes because the cutter isn't plunging in one place on the part every pass and gouging the final piece. Ramping is basically the cutter lowering itself over the course of the cut like a giant helix around the part and it does so in a manner that it takes the same depth of cut the entire time.


I continued to select one feature at a time and continue on with this. There are some features though, like the drive square and the teeth that I had to do multiple operations on because I didn't want it to take forever with the 1/16" endmill. I broke it up, so it would rough out the geometry with a larger end mill, then go in and do the final passes with the 1/16" endmill to get the final geometry I want.

By the time you are all said and done, if you haven't through the computer out the window in frustration, you end up with something like this.

The areas that are almost solid teal are where I'm planning on using the 1/16" end mill. The reason they are like that is because you have to take tons and tons of passes because 1/16" are extremely fragile so you can't remove a lot of material with each pass so the tool path shows up as a solid teal blob.

There's even an animation feature, so you can make sure your program isn't going to make any funky cuts in places that it's not supposed to because of wrong parameters.





Ta daaa!






If you look at what the machine actually reads, you're looking at 441 lines of this non-sense.




 
 

 

 

Wow.......Great thread man.....enough said

Awesome.

I wish I had more time, to work on the fun ones.

Epic thread, when you get this finished up I'll purchase one from you on EE just because i would be happy to support your efforts and struggles doing all this work.

+1

So close, then my unrelenting quest for perfection kicks in



I wanted to see if I could get away with not using a 1/16" end mill, so I redesigned the wrench and it seems to fit, but I think I might be able to do better.



I have a barrel nut on order from Casey at Lawmen's. So when that gets here, it'll be a few more test fits, then hopefully I can finally start making some chips.

how much will these run? I need one too...otherwise i'm just going to make my barrel nut look like butt because i'll force it on without the right tool :)

I highly doubt (unless otherwise noted in prior posts) that unclemoak will manufactur these bbl nut wrenches for sale without KAC's consent and agreement, since the design is in most part, is property of KAC

I seem to recall that they are not against making the tool.

Mark

Disclaimer: IANAL.

Reverse engineering is not infringing. However, it is criminal to steal proprietary info (i.e. KAC's manufacturing CAD files), criminal to steal a physical specimen, a tort to violate an NDA (i.e. EULA), and tort to misuse a trademark (i.e. counterfeit "Aimpoint" sights). As best as I can gather from the history of the thread, none of that happened.

KAC did approve of his efforts a few pages ago.

i knew I saw it somewhere....sinus infection getting the better of me. GO UNCLEMOAK!!

Mark

I wasn't questioning unclemoak. I think what he's doing is great. I'm aware that reverse engineering is all good if it's for your own pleasure. I was talking about manufacturing something of the same design as another manufacturer for your own profit. I havnt kept up with this thread. I read a post that I thought was towards unclemoak about selling the urx bbl nut wrenches (not knowing whether or not KAC approved of that)

unclemoak, my hat sir, is off to you.

Thanks again.





Bill

Awesome thread.

Based on 30+ years in manufacturing (from shop floor to running several companies, and consulting) this is one great presentation.

It is truly impressive that such a great "article" would appear in a forum thread –– well done to all.


I must also note –– I think I would buy it assembled, but the actual pictures of the assembly made it look a lot better (more doable) than it read.

Hi folks,

Yesterday I installed my URX II and than this by 70 ft.lbs. I don´t know that I achieved the 70 ft.lbs:

http://www7.pic-upload.de/05.02.11/sws2d3wbt6yz.jpg
http://www7.pic-upload.de/05.02.11/ttcwlb8hhhv4.jpg
I wrote it KAC, they read it, but I did not become an answer.  What is your opinion about this.

Best Regards

Bummer.  I am thinking they will replace it at a minimum.

sometimes you get a dud when it comes to the metalurgy. This will be very interesting though...I own an SR-15E3 and I am in Canada. I have been always worried about warranty support as they will not ship up here. So I am definitely curious as to how they will support this....sucks cause it is a 250.00 tool. Part of the frustration, is that other companies that sell ITAR controlled items will honor warranty issues and there are exemptions/provisions in place to allow for this - I recently experienced this with Surefire and weapons lights.

Mark

A "proof" that the ZERO Risk is not on our world !
Strange for the great maker Knights.

zero risk is correct

however, anyone that thinks that a manufacturer is beyond making the occassional flop is fooling themselves......the obvious trick is to minimize the occurrence of the flops further to this though, is how they react when they do flop is of equal, if not more importance.

Mark