Using the JFORM D cell forming tool

Step by step instructions on using the J&S Tactical line of tools for your form 1 build
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Using the JFORM D cell forming tool

Postby Jim » 26 Dec 2015 08:10

JformD004 Instructions
Before starting, use gun oil on all the parts to keep the tool from wearing out.

Be sure to follow the steps in order as show below. Drilling the hole prior to forming will not give you an accurate plug since they stretch when forming.

1. Put the lower female die into the die holder with lots of oil.
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2. Put your new unformed expansion plug on the female die and slide the 3 inch sleeve over both parts.
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3. Slip the top Male die into the sleeve

4. Put the assembly into a heavy duty vise or a hydraulic press. Vice shown here.

5. Using the vice or press, slowly form the plug. Some oil may bubble out of the sleeve, that's normal. Note, do NOT use excessive force. Once you feel the stop compressing, STOP. You can always press more if it's not fully formed. You can't press less and you can damage the tool. It only takes about 1 ton of pressure to form the plug. If you over pressure it, your warranty will not cover it.
Before pressing
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After Pressing
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6. Remove the tool and the sleeve. Sometimes the formed plug can be stuck on the die. Just use an old drill bit turned backwards and slip it into the female die from the bottom and carefully tap out the stuck plug. DO THIS BEFORE THE NEXT STEP. I have an old allen wrench that I ground off the bend and use that instead of a drill. A 3/16 bolt will also work. Make sure the end that pushes against the plug is ground flat and not sharp.

6B. (STAINLESS PLUGS) In order to drill stainless plugs, you must do an additional step to prevent the much harder plug from spinning in the tool. Clean the bottom die and the top die completely to remove all oil with a solvent or choke cleaner spray. Get all the oil residue from the tool. Do the same for the plug itself. Blow them off and make sure they are dry, then take a strip of masking tape and very carefully wrap ONE layer around the tool as shown in the picture. Trim it to fit. Be sure to leave a tiny gap on the ends. DO NOT overlap the tape. This will insure the plug will not spin in the tool during drilling. VERY IMPORTANT: do not forget to completely oil your tool when done otherwise it will rust like mad overnight.

7. Reassemble the parts just like before when you formed the tool and take it to the drill press for drilling. Carefully drill out the 3/16 pilot hole using a NEW drill bit. Take your time. Make sure your drill bit is a carbide high quality type and not a cheap china made one.

8. Disassemble the parts again and using the included stainless steel bolt, washer and nut, fasten the formed and
drilled plug to the female die. If the bolt is too long for your chuck, you can cut it off with a hack saw.

9. Put the entire assembly in the drill press chuck (1/2 chuck required) and using a file or sand paper, reduce the outside diameter of the plug so it fits snugly into your tube without having to use a hammer or force. They should be sized to push in with a finger.


Remove the formed and center drilled plug from the tool, then carefully drill it out to your desired final size using a NEW step drill. Accuracy is the most important thing. Do not rush this process and you will have a high quality product when you are finished. It will be easy to disassemble and clean since the plugs were custom fit to the tube. Remember, you are using a forming die that is steel on steel. DO NOT SKIP THE OIL, you will gall the tool and void your warranty.

A properly completed and very accurate plug.

Another tip from forming hundreds of these. You can purchase "pre formed" plugs on the net and save a few bucks. Most of those are pressed into shape using this tool. Selling a plug with a hole is a federal felony. The problem is this. There is NO accurate way to drill the center hole to close tolerances without a die to hold the drill absolutely straight and centered. It's impossible and you will scrap plugs over and over. That is only part of the problem. The other half is the plugs are too large to fit the tube. I make all mine so that I can push the plugs and spacers into the tube with a piece of pvc pipe or wood dowel. Snug and not loose. You have to size each plug down by hand until you can do that.

Some say you can put a 3/16 bolt and washer through the center hole and do it. Try it. The hole is drilled through thin metal at an angle. How can you get it exactly centered with a couple of washers? Tighten it up real tight and you just messed up your taper. Again, not possible to do a quality job. With my patent pending tool, you get an exact size and perfectly centered hole every time. Remember your making a precision item for your weapon. You should take time and care to do this as perfectly as possible. You wouldn't put your scope on with sheet metal screws would you?


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