Well we have just about completed all the front barrel supports. So the next few posts will be videos of cnc machining the last two ops on the cnc lathe.
We have actually started on the rear barrel supports now.
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I have taken a break from working on the VG1-5 project to upgrade a piece of equipment. This upgrade is being done on my little Chinese lathe. The brand name is Acra Turn and was obtain from a machine tool supplier that then went out of business, but it is just another Chinese type lathe that is available from numerous suppliers. I initially installed a set of dro’s from CDCO out of Illinois (https://secure.sigma-star.com/cdcotools.com/index.php
They lasted less then one year, so while still under warranty the bad rail was set back. While inexpensive they were not worth the aggravation I went through to get a replacement rail. It took almost a year and numerous calls and finally a call to Home Shop Machinist ( http://www.homeshopmachinist.net/home?noredirect=true&noredirect=true) to get a new rail sent to me. HSM was great in there help and I cannot thank them enough. Also, to be honest my neighbor also bought a set of dro’s at the same time and I also obtain a second set for my other lathe and neither of the other ones have failed. When the new rail came in it was the wrong size and too large for my lathe and then the second rail failed. At this point I had just had enough. I tried using dial indicators, but to be honest that gets a little old.
I need to make 60 of the same parts and dro’s were the only answer. About that time MSC was having a sale on Mitutoyo dro’s ( whttp://www.mscdirect.com/?cid=ppc-google-Brand+Core+–+E_sWusaD5lR_msc_e_27864417304_c_S&mkwid=sWusaD5lR|dc&pcrid=27864417304&002=2167139&004=8097512824&005=42450341&006=27864417304&007=Search&008=&025=c&026=eb ) and while more expensive then the cheaper brand it was time to order a set.
The next 9 days was an interesting trial of aggravation. This is that story. One of the problems with the little lathe is the carriage lock. It sets right up next to the cross slide and is hard to access in normal times and impossible to access with the dro installed.
So a special lock was made to set flush on the carriage.
They still did not fit due to the height of the tool post and the height of the rails. There was no way to swing the tool post around. So now a spacer had to be made to raise the tool post.
The spacer had to be tall enough to allow the carriage lock to work and the tool post to swing around yet still not be too tall as to allow the center post of the tool post to come out of its corresponding hole. Once made it was surface ground to insure flatness.
Now new hold down bolts had to be made. With the additional height the older bolts would not work. So new tee nuts were fabricated and threaded then welded in place and then ground for a smooth fit. After look for thin nuts in the shop to match the all thread it was determined that the original ones would work. With a lathe that has all metric screws these were American standard. Installing the dro’s required a .004 run out over 40” both parallel and linear.
This was the challenge. The first attempt was to attach the dro to the side of the lathe bed and just shim to the correct run out. This did not work. It was attempted and every time it failed. Now I decided to install an aluminum block on the side of the lathe and machine it so the block was square and eliminating the draft angle of the bed casting. I don’t ever recommend doing that. Then just a block of aluminum was attached and shims were again used. Again, not so good.
The method that worked and allow us to bring it into spec was custom made brackets.
We made a set for the head stock of the lathe and for the tail stock.
Once the dro was installed and brought into spec then the center bracket was made and installed.
After the center bracket was installed the dro was tested and still found to be in spec.
The only grip that I have is that the tie in for the wires only attach on the ends and not in the center. Thus making it difficult for the counter to set in place.
Because of the weight of the small lathe and where it sat in the shop this project would not have been possible without the industrial skates from Northern tool. These are the skates the made it possible (http://www.northerntool.com/shop/tools/product_200356890_200356890?isSearch=144020-1451).
So now the project is completed and the lathe back into it’s proper place we are back to working on the VG1-5 project. Stay tune for more updates. We have continued with the front barrel support. The first three ops have been completed and now we are starting on op 4.
This op is being completed on the small lathe with the new dro’s installed. The first step is to mill out the bottom of the larger hole to provide a flat surface for the spring.
Once completed we use a boring tool to open the hole to .006″ undersize then finish with a reamer.
I hope you enjoyed this update and stay tune as we progress. By now everyone thinks that I have fallen of the end of the earth, not true. It has been real busy both with my life and in the shop. Just a couple of update photo’s of progress in the shop. First is that the first, second and third op’s are now completed on 20 bolts.
and the first and second op’s are completed on the front barrel support.
Hope you enjoyed the update.
Today we are going to stamp and machine the trigger guard. We start with a sheared piece of 2 mil sheet steel. Initially we tried 1 mil but found that it was to easily deformed. Next was 1.5 mil and still did not look correct. So 2 mil gave us the correct look without too much weight gain and was still workable. First, a short video of the process, and then we will look at each step with some photos…
Here are the pieces of starting material, cut to proper size:
After shearing the piece is de-burred, lubed and stamped in the forming die.
This is a look at the inside of the die.
After stamping the trigger dies are set up in the fixture for machining and drilling.
Now the final look of the part.
Now all the trigger guards are completed.
In addition to being the trigger guard it is also the support for the bottom of the stock.
Hope you enjoyed this post and stay tuned for more on the VG1-5 build. Here is the front barrel support. This part accomplishes a few objects. It supports the front of the barrel, is the guide for the recoil spring, acts as a seal for the escaping gas and locks the upper receiver together. So while a simple part to make the tolerances have to be maintained. This is a picture and solid model of the part.
There were two of these made and different methods were used to do it. The final method is the one that we will use when we cnc machine them for a production run. I must apologize in that I did not take a great deal of pictures while making this part. The time constraints required that it be made in a hurry to take this project to the next step. The first method was to turn the out side to the proper dimensions then cut it off and bore and ream the inside.
While this method worked the concentricity was a little out, but still with in spec. So a different method was used the second time around. With this one I bored and reamed the inside of the part to the desire dimensions and then turn the out side between centers to. This allowed the inside and outside to concentric.
the final step is to cut out the locking groves. This was accomplished with a rotary table.
I have an opportunity to interview the owner of the heat treating firm that I go to.A very knowledgeable gentleman that has been in the business for over 30 years. That being said I have always found heat treating to be one of the mystic black arts in the metal working trade. They do ferrous and non ferrous heat treating. And they do terrific work. I have used them for years. So here is my request. What questions would you like me to ask him? We have an opportunity to learn a great deal, lets take advantage of it. Just A quick note for todays post. I have spent the last two weekends building a barn for a friend so not a great deal of time to write a post. There is something not right about a 60 year old framer with a 65 year old helper. There has been some work completed on the VG1-5. I will post about this later this week. For now it is enough to say that a computer generated solid model is only a starting point. When we completed the first two samples a couple of problems arose. As for today I am at the surgery center for a little work on the knees and will be out of commission for the day. I will post the machining of the test barrel, front and rear barrel supports and the problems encountered later. Thanks chuck Introduction Now that you have following along with this build I guess it is time to introduce myself. By now you know my name is Charles, however after someone meets me they generally just call me Chuck. So, on this site just call me Chuck. I have three passions in my life. The first is my wife of 33 years. Generally if you see a picture of me it was taken by her. She feels that there should be a human touch on this site and not just gun pictures. Not only is she my wife, she is my best friend, and travel companion. During my trips to study small arms she will spend a great deal of time copying information for me, which allows more time for me to do research and take pictures.
The second is small arms. My earliest memories are of guns. While living in Europe as a child I can remember trading cigarettes for old guns and then getting in trouble for it. I bought my first gun when I was 14 after I moved to the states. I have been studying and collecting them ever since. I enjoy all types of small arms. From cheap single shot pistols to the most expensive double guns and machine guns. Not only do I study them, I enjoy doing everything related to guns; from buying parts for weapons that I will never own to buying books on them. My library is about 3,500 books and magazines, a number of them in languages that I will never be able to read. I have had the opportunity to meet some of the greatest gun designers and collectors and have enjoyed the experience. A few of them I consider my closest friends. When the finances allow it, my wife and I travel the world to photograph and study weapons. I do not go anywhere without my measuring tools and camera, and if allowed, will take hundreds of pictures of a single weapon.
My third passion is machining. I have loved working with wood and metal all of my life. I bought my first tool when I was not even a teenager and have been buying them ever since. I have what I would call a nice advanced home shop where I play every chance I get. In the future we will take a tour through it and chat about each of the major items and what they are used for. With that being said, I do not know everything about machining. I consider myself to be an advanced amateur and I try to learn something new every day. In addition to just buying machines, I also build or modify a number of them. Expect to see that on this site as well. So everything is not just guns but also the equipment necessary to make them. A number of articles will deal with the fixtures and tooling necessary to build a weapon. With the advent of the CNC machinery that my shop has up-graded to, we will also cover manual machining, forging, casting of non-ferrous material and welding.
Now for the rest of the story; I own two businesses and generally work 12 to 14 hours a day. I will attempt to post at least two to three times a week as the builds go along. English is not my strong point, so if your comments are to bang me on that, just don’t. Also, with all the photographs I take, you would think that I would have improved over the years. I have not. Thank God for digital cameras because they allow me to take enough pictures that something will eventually turn out okay.
This site is going to deal with the design and manufacturing of small arms. I have a weapon manufacturing license and a SOT license. What this means is that I can build and register any weapon except a destructive device. There a number of projects in the works and I generally work on 3 to 4 at a time. We will be covering these projects from concept through the final product. The modeling program that is used in my shop is ‘Solid Works’ and the cam program is ‘Master Cam’. Everything will be discussed from the good designs to the real mess-ups that I can do on occasion. A number of the projects have a quite a few revisions to get to a part that will work. During a project I will attempt to post a link to where I obtained the equipment, or material, thus making it a little easier for you as well. This site will be picture, and eventually, video heavy. It is just a lot easier to explain something that way then with just words. I hope you enjoy the projects and I will attempt to answer any questions that I can. There are a few things not to do. Do not ask me for engineered drawings. Most of the items that will be built here have no drawings and I have spent years reverse engineering them. Also, I will not post engineered drawings on this site because it is a worldwide site and some countries do not allow their citizens to have access to that kind of information. I do not sell partial builds, everything I make is to completion. It has to be heat treated and proofed to verify safety. I have known Ian from Forgotten Weapons for years and was part of the starting process to get Forgotten Weapons up and going. It is Ian’s site and he has done a great job with it. Ian will be helping me with this site as well. I hope you will enjoy this site and learn something from it. Please feel free to comment and ask questions. If anyone knows of a manufacturer that would not mind being interviewed, please let me know. Chuck Well more work has been completed on the solid model of the type 99 magazine. We have now finished both side with feed lips and bottom plate rib. Soon the follower and lower spring plate will be completed. When all the parts are completed it will be off to the 3-D printer. Here are a few more solid models to check out.
We have now completed the entire magazine. So this is the rest of the solid models. First the exploded views.
This is it for now. Next will be the machined plastic model. As a side not. If anyone has a rusted/dented unrepairable magazine they want to donate to the cause it will be used to test the final bit of information that we need. Please feel free to contact me. |
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