[yosuthnmasa]

I've got a couple of ACE pre bents and I'm just about ready to glue it on and start drilling the various sized holes. I was thinking about buying the huge set of cobalt drill bits(39.99) from HF but decided that maybe I'd wait and just buy the ones that I just had to have for this go round, and then when there were more funds available take the plunge on the whole set. After looking at the template, I've come across these meausrements for the various holes:.150,.164,.195,.2,.222,.25,.272,.394. Have I missed any here? These are coming directly from the ACE template. Looks like I may be buying the entire set. But, one guy was mentioning how he dropped the set(HF) on the floor and meaured them with his caliper and many of them measured the wrong size. Any suggestions on an alternate source for hardened drill bits?

 

[erikk]

You need a 5mm & a 7mm for the hammer,trigger pins. The rest, if you are screwing it together, use a drill that will allow you to use whatever tap you are going to use for the screw. The selector lever use what the template calls for

 

[Winn R]

Josh--

I think I'm just a distrustful old codger by nature. I take the pins I get with a set, mic both ends, then pick the drill bits and mic it to make sure I pulled the right one.

I drill a little hole straight through then come in on the left side and drill the bigger holes. Opposite on the safety. Measure down from the top edge to check the locations. This only works if you got something to put in the center of the receiver to hold it rigid.

I've got one of those $40 sets and I'm pleased with it. What tends to happen if you buy individual bits is that you never have the exact one you need.

 

[yosuthnmasa]

I'm going to "attemp" to rivet it together. With that being said, are the above mentioned sizes all I'll need?

You need a 5mm & a 7mm for the hammer,trigger pins. The rest, if you are screwing it together, use a drill that will allow you to use whatever tap you are going to use for the screw. The selector lever use what the template calls for

 

[yosuthnmasa]

I drill a little hole straight through then come in on the left side and drill the bigger holes. Opposite on the safety. Measure down from the top edge to check the locations. This only works if you got something to put in the center of the receiver to hold it rigid.

Winn,

I'm not sure if I'm following what you're trying to explain here?

 

[hcpookie]

Winn,

I'm not sure if I'm following what you're trying to explain here?

He's saying that you should drill after the center support is in-place, to be sure you don't get the holes mis-aligned because the sides of the receiver aren't exactly parallel.

 

[yosuthnmasa]

So, with the center support in (it's now parallel and sturdy) you can drill through one hole on one side and directly through to the other parallel hole? Is this what you mean? Couldn't the same thing be achieved if you just drilled each one separate? If for some reason even with the center support in, the two sides aren't perfectly parallel to the eye, then by drilling through both sides, you might get the second one a little off? I'm sure you guys are speaking from lots of experience which I don't have. If this is the easiest way to do it, then I am certainly going to follow it.

 

[Winn R]

Josh

Use the method that works best for you.

If you have a way to absolutely clamp the receiver down and to support it internally, going straight through is fairly easy.

I've got a collection of wood blocks that are cut to fit on the inside the receiver.

On the side walls, I don't use a template. Instead I scribe lines parallel with the upper edge, place a dimple where the holes go.

 

[yosuthnmasa]

I think I understand your post now...its taken me a couple of days now. You drill the holes through both sides with a small bit. That way, if it is off at all you can compensate depending on where the hole falls. As far as scribing lines on the receiver and using dimples..I'd love to hear how you do that. I've had some trouble printing out the ACE template. I've got two copies that are very close, but different in size.

 

[yosuthnmasa]

I was looking over the ace template and noticed that on the trigger holes, there are 2 different sized holes that I need to drill depending on which side you look at. If the template is flat and not folded, the left hole is suppose to be .1950 and the right is suppose to be .2720. First question, why are they different sizes. Second, after looking at a table I have of the drill bit conversions between metric and english, I don't see a metric or english bit that is exactly .1950. The closest smaller number is .1935 (#10) and .1960 (#9) for the next larger. What do you guys use? I looked at a couple of others that didn't have an exact metric match either.

 

[Winn R]

Josh

If you take a look at the Axis pins, the side with the head is larger than the side with the shaft.

 

[yosuthnmasa]

Second, after looking at a table I have of the drill bit conversions between metric and english, I don't see a metric or english bit that is exactly .1950. The closest smaller number is .1935 (#10) and .1960 (#9) for the next larger. What do you guys use? I looked at a couple of others that didn't have an exact metric match either.

Any ideas on why I can't find an exact metric match for some of the holes?

 

[Toten Kopf]

Okay, this is what I?ve come up with as far as drill bits go (If I?m thinking wrong?.please someone pipe in). You have to take into account just how off center the bit is going to be. In another words if you chuck your drill and take a reading on just how out of round it is you would need to adjust the drill bit size for that amount.

Example: You want a .250? (1/4?) hole and the runout (the amount of distance off center) of the drill (in the chuck) is .002? - .004? (like the drill is wobbling .002 - .004?). Well, you wouldn?t use a .250? (1/4?) drill because with the runout your hole would be .252 - .254? which would be to big. You would use a ?D? drill (.2460?) that way with the runout added the hole diameter would be between .2480? and .250?. The small amount of metal needed to be removed to bring the hole into the .250? range is small and a fine rat tail file (brace) would do the job. Remember, we don?t have to rush the job. Take your time and just remove the metal needed.

I know were talking about an AK-47 and it?s loose tolerances so don?t get to anal like me?..lol Guys have built these guns with hand drills so maybe all of my ?trying to be as close as possible is a moot point?.

It?s always easier to remove more metal than put it back. Winn R has a good point about measuring the ?REAL? pins before drilling. I know that we all want to make an AK that is universal as far as fit goes but sometimes just making a one off is better. I hope that this helps you in drilling your receiver.

http://www.victornet.com/cgi-bin/victor/reference/Sizes_Equivalents.html is a good site for getting fractional, numbered, lettered, and metric drill size dimensions. So you can pick a smaller drill size and work up. Man have I rambled on, must be cabin/BIY fever.........lol

 

[yosuthnmasa]

Kopf,

That really does help! I didn't know or think about the issues involved with wobbling and how that would offset the size of the hole. I think at this point, not knowing how offset my drill is and not having a drill press, I will go with a smaller diameter bit and work my way up with a file. That should do the trick.

I guess I was assuming that the decimal measurements on the ACE template would have exact matches with either an English or Metric equivalent. Since I've never had a complete drill bit set (with numbers and letters) I wouldn't have known that they don't match exactly with the decimal figures on the template.