Tap Question

[Capt. Fred]

Hi guys,

When I'm tapping holes in my lock or trigger plate I like to tap the hole through the stock of the gun so I'm positive things will thread in easily. The issue is that the normal 2 1/2 inch long taper tap is a tad short to do this easily.

Does anybody have a source for good 8-32 and 10-32 taps that are 3 or 4 inches long? I checked Grainger and they have 6 inch long taps at $50 apiece! :shocked2:

Thanks.

 

[hoochiepapa]

I've run into this, too. What I do is use the tap handle to just get the threads started, then use a needle nose vise grip to thread it as far as I can, then go in from the other side with the tap handle, The threads on the far side have been cut enough to finish the threads straight.

 

[jerrywh]

Do you have a drill press??? If so you can tap those holes the same way you drill the barrel pin holes, with a pointer in the drill press vise. Put the tap in the drill press chuck and the pointer in the vise. Line them up point to point. turn the gun upside down and place the pointer in the hole in the tang. Run the tap in the hhole of the trigger plate and start it once started you can remove it from the drill press and finish by hand or just complete it in the drill press.

 

[Vaino]

Just measured the wood width at the locations where the 2 lock bolts are and the front dim. is 1-3/8" and the rear is 1-1/2" and even the #6-32 tap which is used for the front lockbolt is 2" long. The bbl breech dim. is 1.080 but even w/ a larger breech dim. there shouldn't be a problem. Possibly too much wood is left on both sides because I've never had this problem w/ standard length taps....Fred

 

[jerrywh]

DIDO to flehto. Something is wrong.

 

[Vaino]

Only the sideplate side excess wood would affect the tap length req'd if the lock bolster is up against the bbl. Sorry for the misinformation....Fred

 

[Capt. Fred]

I wonder if the taper tap I've got is shorter than normal to the full cutting section. I measured from the full cutting diameter(discounting the length of the taper) and I come up with 1 3/8 inch to the shoulder where the jaws of my tap handle attach. What I usually do is to loosen the jaws and move the tap out a bit and that will be just barely enough to do it on a C-weight barrel. If I even had 1/4 inch more length to the full cutting area on the tap I'd be good with room to spare.

I measured the gun I just tapped the lock on, and it is 1 9/16 inch wide at the rear lock bolt. Bolster is tight and each side of the stock is the same dimension from sides of the barrel.

 

[Vaino]

My taps are 2 fluted, HSS and measuring the same as you did, here's the dims of my taps....#10-32, 1-15/16"...#8-32,1-11/16"...#6-32, 1-5/8". I'd buy some different standard length taps....Fred

 

[Capt. Fred]

Thanks Fred. That explains my issue. :thumbsup:

 

[buzz]

i use an old clock key that fits my taps
when you need more just pull off the key and the part with tap still in it and finish the job

 

[Birddog6]

All you need is a good start on the tap so you know the angle you are tapping it is correct. Once that is started well, you can take it out & finish it.

You might look in MSC, as they may have longer ones. I prefer a 2 flute spiral tap, they seem to be the strongest for me.

Keith Lisle

 

[Capt. Fred]

I ordered a couple of taper and a couple plug taps. I'll be fine if they have anywhere near the cutting thread length of flehto's taps. :thumbsup:

 

[paulvallandigham]

This is my experience with taps. Once you get any threads started, even if they are not the full depth, you can remove the part being tapped, and finish the tapping with the part out of the gun. The Alignment is "SET" with those few threads.

Again, tho', leave the Gorilla out of your workshop while you run that tapered tap through the rest of the piece so that you get a good, deep thread going all the way through. Take it easy with the Taps, using your fingertips on the tap handle to feed the tap into the hole, no more than a 1/4 turn, then back it out at least 1/8 turn to break loose the chips from the cut, and repeat. Use lots of cutting oil, to flush the chips down the flutes of the tap, and oil the cutting edges. :thumbsup:

 

[Capt. Fred]

Yup Paul, I'm always paranoid of breaking one off so I go super slow. :thumbsup:

 

[Birddog6]

If possible, best to tap Down so the chips fall down thru the hole, rather than horizontal where they stay in the hole & can bind the tap.

Keith Lisle

 

[hoochiepapa]

man, a guy can just learn so much here! So glad I joined. I never thought of that. Thanks. :bow:

 

[Melton Kidd]

Information for what its worth; Most hardware brand taps are made in China and the top portion is to big to use through the stock and the cutting tip is not long enough to reach. I am now buying machine screw taps from Brownells and TOTW. The prices are comparable and I order taps from which ever I need other items from at the time.

Mel

 

[paulvallandigham]

When it comes to getting the chips out of the threads, I am a " Picker" and a " blower". I use whatever I have that fits up into the hole that being threaded- usually a piece of wire, or a scratch awl, and then remove the piece from my bench vise, and blow into the hole to get the chips out that resist "picking". It all depends on how thick the piece of brass or steel I am trying to thread as to how much picking and blowing I do. But, I don't even like the feel of the tap taking a second "Bite" of a chip!

I suppose if I had a real " SHOP" I would just use the nozzle on my compressor to blow a high velocity jet of air into the hole to clear the chips instead. :thumbsup:

 

[Vaino]

All my standard taps have a larger body than the threaded portion and this dim. determines the body drill size. Because of the shallow, through tapped holes in MLer parts {the rear lock bolt tapped hole is the deepest}, backing off the tap after 1/2-3/4 turn to break the chips is possibly more important than actually clearing the chips. Another cause of broken taps is starting at an angle and then trying to straighten it out. Also, probably the most broken tap size is #10-24 because of it's greater thread depth and should be avoided if possible. I use regular machine oil for tapping and have had no problems using it whether in the tool room or at home. Happy tapping....Fred

 

[Capt. Fred]

Yup, I read on this board a long time ago about only going 1/4 turn or so at a time, and so far (knocking on wood) I have not had any serious problems. I was real confident with my skills working with wood, but all the tips from you folks about working on steel have been a real help. I just fit my second breechplug and they aren't too scary anymore either!

So, :thumbsup: Thanks guys.