Piloted Tap Driver/Handle

[Artie]

I have a heap of small holes to tap shortly and I want them to be firstly straight, and secondly I dont want too many (nil!) broken taps. I therefore need a piloted tap driver.

Almost all my holes are 4 BA so ive built this around that particular size. I will make a few more in common sizes though...

The unit itself is quite simple BUT... I had my first attempt at knurling, and while not perfect, Im pretty impressed with the result...

I might just go and knurl something else..... ;D

 

[cfellows]

Nice. How do you fasten the tap into the holder?

Chuck

 

[bearcar1]

Yes please, tell us some more about your newly made tool. Materials, sizes, etc.

BC1
Jim

 

[Artie]

Hi Chuck and Jim, the tap is held in place with a grub screw (other side of the tool) as its only a small tap driver it doesnt need a heap of clamping power. I thought about using 2 screws, each side of the tap drive flates but instead ran one straight onto the shaft.

the stuff was all scrap from the "I wont throw that away box...". The tap holder itself was a piece of 12mm bright steel rod, I think you guys call this drill rod?? Not sure about that...

The 13mm plate for the 'handle' was a random piece of square which I centred, drilled for interference fit on the tap holder shaft. I then drilled the holder for the tap, tapered the end and pressed it into the handle.

Here's where I got paranoid and silver soldered the finger plate to the tap holder. It was a tight fit and this operation was not required..ah well... what would I have said if it ever started to slip?

Then chucked it all in the lathe and turned the finger plate to a round profile (I hate that bit, turning square edges into round) and knurled the finger edge.

I found a piece of reasonably heavy wall tubing which I drilled for a clearance hole on the tap holder shaft and cleaned up the scale on the outter surface. This mounts in the mill and guides the tap holder square etc. This is a pretty loose fit as its only a guide and needs no friction.

Guide tube and finger grip are mild steel. It all only took about an hour and is just another addition to my range of 'miniature' tooling...

Got another little piece which I use a fairly often, will try and get pics up in a few days. Piece of 20mm square mild steel bar about 75mm long. I drilled it with a variety of holes along the centre line (12, 10, 8 and 6mm)and then split the whole thing down the centre.

Great for clamping round pieces of shaft in the vice for whatever operation.


Actually, before I add pics of that I'll remake it neater... :big: split it with a hacksaw cause I didnt have a slitting blade thin enough, after seeing the items you guys produce, Id call that a lil rough... ;D

 

[bearcar1]

That's pretty slick Artie, I like it. I do need to make up something like that as busting a tap just drives me nuts, not to mention the PIA getting the broken piece out and on and on. You all know what I mean. That rig would seem to solve a great deal of that problem by using finger pressure only to twist the tap as opposed to the ham-fisted methods that some use. Neat little project, thanks for sharing.

BC1
Jim

 

[Deanofid]

Good show, Artie. A very handy tool.

Dean

 

[Artie]

I wish I could take credit Dean, its simply a variation of others i have seen on here and other sites. ;D

 

[tmuir]

I've made a couple of very similar tap holders and they would have to rate as one of my favourite shop made tools.
I use them all the time.

Here is a couple of photos of mine.

They are well worth the time to make.
God to say I don't like knurling mild steel as my cheapo knurling tool isn't very good on steel.
One day I will need to buy a better knurling tool.

I like the idea of fitting the large section to the rod for knurling.
Saved yourself an awful lot of turning.

 

[Artie]

Hey Tmuir, its that sort of pic which inspired me in the first place. I used my tool tonight and I have to say im bloody impressed with it. Thanks to all for the inspiration.

Later.... Artie

 

[toolsrul]

This is what I use & make. Real sensitive feel.