Tap (Wrench) Blues

[graham-xrf]

Yes - I have been here before, in a way, and I am promising myself to I will eventually be making my own tap wrench. There are lots of good examples, like the one from This Old Tony, and the reproduction Starret from Brandon Sander (Inheritance Machining). Right now, I am in what Brandon would call "nested side projects", so I have been surviving on the kind of cheapo kit that comes in the flimsy metal box with the "set of taps". I did purchase two supposedly "better" types, meaning the cylindrical kind as shown in the picture, that being the "bigger" one. It might even prove to be a bit better, if it would open up far enough for me to find out! The other one came out the taps set box.





The hardened bit measures 9.99mm The slot it slides in measures 10.64mm. For the non-metric among us, that is more than 0.025" of slop. Threads are coarse, and there is only hard steel up to the tap, so I don't expect it will be able to "tighten", but this one lets the handle fall off every time I let go to grab again after a 180° turn. Somehow, that handle loosens itself, by itself, and if the tap is not already part-way up a hole, it will just drop out of the wrench!

I am tapping for stainless thread inserts into the 1/4" thick aluminium angle bracket to take M8 bolts, so the tap for the inserts looks like M10. I always use inserts into aluminium. How is this "nested"? It's for my super-strong trolley with 10" wheels, and a steering arrangement in the front that does not have a central pivot guaranteed to allow the whole thing to tip over. It has to move my mill, and other machines. I already mis-spent £120 on an allegedly "strong" trolley rated (they say) to 350kg (770lb) that turned out totally unusable to entrust my machines on. Mine homebrew version is made of ply and 2 x 4(s), and has a Ackermann steering link so the front wheels can stay where they need to be. Unfortunately, the critical bits do need some M8 bolts.

 

[mmcmdl]

If you were only in the states .

 

[WobblyHand]

Yes - I have been here before, in a way, and I am promising myself to I will eventually be making my own tap wrench. There are lots of good examples, like the one from This Old Tony, and the reproduction Starret from Brandon Sander (Inheritance Machining). Right now, I am in what Brandon would call "nested side projects", so I have been surviving on the kind of cheapo kit that comes in the flimsy metal box with the "set of taps". I did purchase two supposedly "better" types, meaning the cylindrical kind as shown in the picture, that being the "bigger" one. It might even prove to be a bit better, if it would open up far enough for me to find out! The other one came out the taps set box.

View attachment 442418

View attachment 442419

The hardened bit measures 9.99mm The slot it slides in measures 10.64mm. For the non-metric among us, that is more than 0.025" of slop. Threads are coarse, and there is only hard steel up to the tap, so I don't expect it will be able to "tighten", but this one lets the handle fall off every time I let go to grab again after a 180° turn. Somehow, that handle loosens itself, by itself, and if the tap is not already part-way up a hole, it will just drop out of the wrench!

I am tapping for stainless thread inserts into the 1/4" thick aluminium angle bracket to take M8 bolts, so the tap for the inserts looks like M10. I always use inserts into aluminium. How is this "nested". It's for my super-strong trolley with 10" wheels, and a steering arrangement in the front that does not have a central pivot guaranteed to allow the whole thing to tip over. It has to move my mill, and other machines. I already mis-spent £120 on an allegedly "strong" trolley rated (they say) to 350kg (770lb) that turned out totally unusable to entrust my machines on. Mine homebrew version is made of ply and 2 x 4(s), and has a Ackermann steering link so the front wheels can stay where they need to be. Unfortunately, the critical bits do need some M8 bolts.

I have never had luck with these cast tap heads. Or cast die heads. They are just plain junk. I had the tap head break on mine simply in normal (non-high torque) use. Either a Starrett 91B or a 93B (or their equivalent) are far superior. Once you have used either, you won't go back. Both the 91B or the 93B lock up very positively on a tap. The 91B is a similar style as above, but with a solid tool steel head. The 93B is a tee handle type tap wrench. I don't have very many fancy tools, but my tap wrenches are all Starrett. Not saying they are the best, but they are light years better than the style you showed above.

Appreciate you being in nested projects - I seem to fall into similar situations. I used to have a lot of trouble tapping, with the old dreadful "hardware store" taps and tap wrenches. Same as you, I had the handles fall off, in the middle of work, or the wrench loosening. All that drama disappeared after buying quality taps and tap wrenches.

 

[graham-xrf]

I have never had luck with these cast tap heads. Or cast die heads. They are just plain junk. I had the tap head break on mine simply in normal (non-high torque) use. Either a Starrett 91B or a 93B (or their equivalent) are far superior. Once you have used either, you won't go back. Both the 91B or the 93B lock up very positively on a tap. The 91B is a similar style as above, but with a solid tool steel head. The 93B is a tee handle type tap wrench. I don't have very many fancy tools, but my tap wrenches are all Starrett. Not saying they are the best, but they are light years better than the style you showed above.

Appreciate you being in nested projects - I seem to fall into similar situations. I used to have a lot of trouble tapping, with the old dreadful "hardware store" taps and tap wrenches. Same as you, I had the handles fall off, in the middle of work, or the wrench loosening. All that drama disappeared after buying quality taps and tap wrenches.

This may be the right place to put some aspirational stuff. Like a nice picture of a 91C. That type has all sorts of fancy spring-loaded stuff in the handle.



For those who want to roll their own, there is a college course drawing of one in that style. it's a bit of a challenging project, with a fair amount of heat treating skill involved.


Then there is a very traditional style..



That type was done by This Old Tony, and other YouTube folk have made versions.

The idea of having separate heat treated bits, so as not to have the middle body made of all quality hardened tool steel is clearly about manufacture cost. It's not altogether a bad idea, but seems always to depend on the design of the handles having to serve more than one function. I found an old drawing that lets the handles be handles, by rotating the jaws body to allow it its own clamping screw [Fig. 206 d ]. That one is of a die wrench of a sort I would doubt, but the idea could be used for a tap wrench.



A Starrett 91B, the 9" body length version, I see is $91.23 + on Amazon, with another $38 or so to deliver to UK. The Starrett91C (12" long) is $140.15 with 10 left in stock. The cost to make one's own would likely far exceed that, but it is the sort of thing we do. We make a tool for life, and we can get very proud of something like that.

I did get that fond warm "Wow - I do like it" feeling when watching Brandon make his version..

If one wants to be able to tweak dimensions to anything desired, there is a FreeCAD file of a Starrett copy.


If you like Fusion360, or some other CAD, then here also is the STEP .STP model in a ZIP. Modify at will..

 

[Provincial]

I guess I'm spoiled by tripping over vintage GTD (Greenfield Tool and Die) tap handles at garage sales for $1.00 to $10.00. Ten for the huge ones over two feet long. A buck for the smaller ones less than ten inches long, and the collet-style holders. I paid $5.00 for one that will be over three feet long once I repair the fixed handle - the moving jaw and that handle are fine.