I kind of promised to do this a while back....will need to do a few sections to do it justice and add enough detail to be truly helpful.
I will try to cover squaring up, trigger and hammer holes, safety selector hole tonight. Maybe more depending on time.
Whether you have a JIG and a drill press or a mill squaring up is step one. notice the lower is sitting in a pillow block that I made before starting this project. An edge finder is chucked up in the mill, the left hold down is lightly clamped. the right side of the work is a bit towards the back of the mill. at this point move the cross feed until the edge finder runs the entire length of the work piece. the piece should have moved into alignment and is now square to the spindle. tighten the hold downs and re-check that nothing shifted using the same method and checking for binding on either side.
Lining up on the piece and zeroing the DRO's. Nearly all measurements for where to drill and mill start at the forward take down pin holes. I start at the back one
yeah sounds wrong but the reasoning is justified in a second. I use a 1/4" piece of drill rod blank and chuck it up. move the table until I can insert it into the back take down pin hole. Raise the chuck and slide the table on the x-axis 6.375". this does 2 things if the drill stock will not drop into the front take down hole on the x-axis then the 80% blank is not made correctly send it back your upper will never align correctly. if it is off on the y-axis then go back to the first step and square up properly. if it drops in nicely zero your DRO's
The DRO's in the picture show the correct x and y coordinates for the trigger hole to be drilled, trigger is 4.447" behind the center of the front takedown pin and .689" below the same. either use a centering bit or as in the picture short chuck the bit to prevent deflection when starting the hole. The hammer pin is located at 3.604" and .375" respectively. each of these holes need to be .156" dia, I do not drill them to this size I drill a smaller hole and use a chuck reamer to attain the .156 dia hoile. Why? if you have a good set of calipers or a decent micrometer measure a few drill bits and see if they come up exact, few if any will, a decent reamer however will produce a hole usually to within 4 digits right of the decimal. once drilled and reamed move to 5.572" and ,464", I start with the same bit as the hammer and trigger holes as a pilot then chuck up a ,375 bit and drill through for the safety selector. again the actual hole size required is .376 and I use a chuck reamer to obtain this diameter. These are things the people selling jigs don't tell you, when the safety is reamed in to this exact tolerance it slides in like butter and operates like glass no binding at all. even if using a jig and a drill press the reamers are just a good idea your pins and safety will fit correctly and operate smoothly. sound picky? it won't when you are putting your LPK in, or when applying 20 pounds of pressure to take your safety off at the range, the little things count!
At this point you can release your work from the hold downs and it should look like this. (note the .376" chuck reamer, just used to ream the safety selector hole)
Ok all hopefully I will have some time in the near future and we will move on to the trigger group area. IF this is helping you in any way say so! much easier to be motivated to write more it folks find it helps.
I will try to cover squaring up, trigger and hammer holes, safety selector hole tonight. Maybe more depending on time.
Whether you have a JIG and a drill press or a mill squaring up is step one. notice the lower is sitting in a pillow block that I made before starting this project. An edge finder is chucked up in the mill, the left hold down is lightly clamped. the right side of the work is a bit towards the back of the mill. at this point move the cross feed until the edge finder runs the entire length of the work piece. the piece should have moved into alignment and is now square to the spindle. tighten the hold downs and re-check that nothing shifted using the same method and checking for binding on either side.
Lining up on the piece and zeroing the DRO's. Nearly all measurements for where to drill and mill start at the forward take down pin holes. I start at the back one
yeah sounds wrong but the reasoning is justified in a second. I use a 1/4" piece of drill rod blank and chuck it up. move the table until I can insert it into the back take down pin hole. Raise the chuck and slide the table on the x-axis 6.375". this does 2 things if the drill stock will not drop into the front take down hole on the x-axis then the 80% blank is not made correctly send it back your upper will never align correctly. if it is off on the y-axis then go back to the first step and square up properly. if it drops in nicely zero your DRO's
The DRO's in the picture show the correct x and y coordinates for the trigger hole to be drilled, trigger is 4.447" behind the center of the front takedown pin and .689" below the same. either use a centering bit or as in the picture short chuck the bit to prevent deflection when starting the hole. The hammer pin is located at 3.604" and .375" respectively. each of these holes need to be .156" dia, I do not drill them to this size I drill a smaller hole and use a chuck reamer to attain the .156 dia hoile. Why? if you have a good set of calipers or a decent micrometer measure a few drill bits and see if they come up exact, few if any will, a decent reamer however will produce a hole usually to within 4 digits right of the decimal. once drilled and reamed move to 5.572" and ,464", I start with the same bit as the hammer and trigger holes as a pilot then chuck up a ,375 bit and drill through for the safety selector. again the actual hole size required is .376 and I use a chuck reamer to obtain this diameter. These are things the people selling jigs don't tell you, when the safety is reamed in to this exact tolerance it slides in like butter and operates like glass no binding at all. even if using a jig and a drill press the reamers are just a good idea your pins and safety will fit correctly and operate smoothly. sound picky? it won't when you are putting your LPK in, or when applying 20 pounds of pressure to take your safety off at the range, the little things count!
At this point you can release your work from the hold downs and it should look like this. (note the .376" chuck reamer, just used to ream the safety selector hole)
Ok all hopefully I will have some time in the near future and we will move on to the trigger group area. IF this is helping you in any way say so! much easier to be motivated to write more it folks find it helps.
