What tapping tools are needed ?

johnnym

johnnym

Joined
Dec 13, 2005
Messages
170
Could someone educate me on how to tap small holes for folders, like 2-56 or 1-72 sizes. The taps seem fragile. I would like to avoid the cost of a tapmatic if possible.

Thanks in advance,
-John
 
If you avoid a tapmatic, you will pay a lot more than the price in broken taps, ruined folders, and mental anguish. Tapping a 1-72 hole requires some sort of tapping setup.

You will absolutely need a can of Molly-Dee. Good taps of the right type are also important.

The only "cheap" tapping rig I have seen was one that a chap made from an inexpensive table top drill press. He would clamp the part in the cross vise, drill the hole, disconnect the belt, put the tap in the chuck, and run the tap in - turning the chuck by hand. All this was done without moving the work or the cross vise,.... and then was repeated hole by hole. He did not use the press for any other task than the drilling and tapping of small holes.
 
I have hand tapped 2-56 by hand using a small T handle and tapmatic cutting fluid.
I have never tried a 1 before.
If I had to try I would drill the hole with the piece clamped.
Take the belt off the drill press.
Put the tap in the chuck making sure it spins true.
Tap buy twisting the chuck 1/2 turn forward breaking the chips every 1/2 turn.
Cleaning the chips out of tap flutes often.
If you see the tap flexing definitely clean and reapply the tapmatic cutting fluid.
THIS WAS ONLY AN IDEA.
Sincerely
 
The above posts are the right way to do it. But I do it the fast way :D

I drill and tap many holes for 0-80 and 1-72. Mostly titanium liners, bolsters and blades for thumb studs. I use one size larger drill than called for and high quality taps. I chuck the tap up in a cordless drill and run it in the hole holding the part in left hand, cordless drill in right hand.

The only time I break one, is when one gets too dull and should have already been replaced. Usually well over 100 holes.

This may not work for everyone, but has worked for me for over 12 years and around 600 folders.
 
I use my drill press for the small taps(only I don't remove the belt, I just don't turn it on), and Don's response about one size bigger drill bit is extremely helpful. On anything 12-24 or larger, I use my cordless drill with the clutch set to medium.
 
I have modified tap wrenches to be similar to these piloted tap wrenches,

http://www.huronindustrial.com/mm5/..._Code=1-391-015&Category_Code=&Store_Code=his

If I had to do it again I would add a sleeve to the ones I made so they coluld move guided by the drill press completely independantly of the chuck rotation. I use spiral point taps for almost everything these days

http://www1.mscdirect.com/cgi/NNPDFF?PMPAGE=297&PMITEM=64930175&PMCTLG=54

The conventional taps where you have to reverse them every 3/4 turn just don't cut it in my book

-Page
 
All good advice above, and techniques that I have used in a production setting when a Tap-matic wasn't available.

One thing I would add is to 'break' the sharp edges of the hole with a countersink before tapping.
 
I have used a tapping block for years for various reasons..Probably worth a mention anyway. But alignment of the tap to the hole is fairly critical on small taps. You can guess why they tend to break.

Pictured for tapping on the cheap (cheaper than a tapping head anyway).
These are easy to make..Measure the big diameter of your tap and drill a hole in a qualified material to just a few thousandths over that diameter.

http://store.curiousinventor.com/tapping-block.html


HTH

Bill
 
This is a great thread! :thumbup: Small taps always give me a headaches and I've not even gone that small yet. :(
 
For the small taps you only need the 30X tapmatic.I picked up on ebay for $160- well worth the money in taps and frayed nerves(waiting for that ominous CREAK just before the CLICK ! ) There are usually a few on Ebay at any time.You just have to be patient.
Don
 
Hello Johnny.
Here's the one I have used for years. It works great. I use the ball of my hand to twirl it back and forth. I would not concider a tapmatic unless your screws are going to be 2X56 or larger. I have been told Don's way works super, but I just can't seem to get around to trying it . Go to KBC part 1-397-513 Frank
 
Don Hanson III said:
The above posts are the right way to do it. But I do it the fast way :D

I drill and tap many holes for 0-80 and 1-72. Mostly titanium liners, bolsters and blades for thumb studs. I use one size larger drill than called for and high quality taps. I chuck the tap up in a cordless drill and run it in the hole holding the part in left hand, cordless drill in right hand.

The only time I break one, is when one gets too dull and should have already been replaced. Usually well over 100 holes.

This may not work for everyone, but has worked for me for over 12 years and around 600 folders.
Click to expand...

How much of the thread profile do you lose going with the larger drill at those diameters?

-Page
 
The trouble with using an oversize drill is a reduction in the strength of the threads, meaning they're more likely to strip due to less engagement. And while the threads in the work piece may be very strong (titanium for example) the threads in the fastener become the weak link. Especially if that fastener is a 300 series stainless steel, which isn't particularly strong compared to a high quality alloy steel fastener.

The difference in strength between a 60% thread and a 75% tapped thread is not that great, probably because the part of the thread that is truncated is the minor diameter, which is probably not where the strength of a thread is found. However when you start going past 50% I think you're starting to really push your luck.

There are times when you have no choice, and if your work is properly "engineered" for it you'll be fine. But I wouldn't recommend going under 60% as a general practice.

my .02...
 
sunshadow said:
How much of the thread profile do you lose going with the larger drill at those diameters?

-Page
Click to expand...

Not much and never stripped a hole. I don't have the numbers in my head, but I'm guessing 2-3 thousandths oversize. Most of my tapping is done in titanium liners and for me the hole must be oversize, or taps will break. Also running a 0-80 tap in damascus, you better have your chit together. :D
 
Don Hanson III said:
Not much and never stripped a hole. I don't have the numbers in my head, but I'm guessing 2-3 thousandths oversize. Most of my tapping is done in titanium liners and for me the hole must be oversize, or taps will break. Also running a 0-80 tap in damascus, you better have your chit together. :D
Click to expand...

Thanks, makes sense.

-Page
 
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