Suitable tap wrench for hand reamers

I have bought a set of imperial hand reamers and want to acquire a suitable wrench to use them supported by a spring tappping guide in the lathe tailstock.

I have some ‘collet’ style wrenches already (first image), but owing to increased leverage I want to try out the jaw type (second image)

Would this be the correct choice? Why does there exist these two styles of tap wrench?

Thanks in advance.

Edited By choochoo_baloo on 05/02/2018 17:27:39

Edited By choochoo_baloo on 05/02/2018 17:28:19

Personally I put the DR 32 collet chuck off the mill into the tailstock and use that to hold the reamer and then run it in with the lathe on it's slowest speed, works OK with hand reamers.

But yes the second type will do the job and will line things up better as your sprung ctr is straight into the reamers end.

First type used if there is limited access, I have seen wrenches with even longer reach capability, you tend to get more wobble as the T bar is further from the tap.

2nd type would be better for hand reamers as it's more controllable.

Tony

I think an element of personal preference comes into the choice but the chuck type can be useful to avoid obstacles like adjacent studs or parts of the item to be tapped, extra long versions are available if required. With the bar type wrenches the centre hole or point is available for a spring centre. The chuck type are only useful up to about 8 or 10mm taps but the bar type are available for the largest taps or reamers. Ratchet versions of the chuck type are available so can be used in restricted access locations.

Mike

I just fitted a longer bar into my 'T' type wrenches. (I know, but its me doing it for myself!)

I also think it is much easier to get the tap perpendicular to the hole with the 'T' type (if I can't do the job in the lathe) - It is easier (for me) to see if the extended stem of the wrench is perpendicular to the face of the work. When I use the bar type wrench, it feels a little odd because the tap always feels slightly 'off-centre', and I have difficulty making sure the tap is perpendicular to the work. I can see if the bar is horizontal in one plane, but in the other plane (at 90 degrees) I all too often end up with a slight tilt, so the tap starts slightly out of vertical.

However, I suspect this is another case of the 'favourite screwdriver syndrome' - probably most people just use the tool they are most comfortable with (mike Poole) or which type comes to hand first

The clue is in the name - hand reamers. They're intended for use by hand with a tap wrench. If you want to ream in the lathe you're better off with machine, or chucking, reamers held in a drill chuck. Personally I don't bother with hand reamers. If the pilot hole has been machine drilled then it's much easier to ream at the same setting with a machine reamer.

As for tap wrenches I've got both types, but almost always use the bar type. They hold the tool more firmly and give better control. I don't have a problem hand tapping perpendicular. I just eye up the tap twice, at right angles, to check it is perpendicular in both planes. It helps if the metal is shiny as you can see the reflection of the tap, if the tap and its reflection are straight then the tap must be perpendicular.

Andrew

For small taps, in the Mill, I use a spring loaded gadget (a Tap Tru?) to keep the tap vertical, while the tap is turned by a small tap wrench.

For larger sizes, I made some holders which convert Taper Shank Reamers to Hand Reamers. The adaptor has a centre in the end, which is steadied by a centre in the quill, while the adaptor is turned by a Tap Wrench on the square. If a hand Reamer has a centre in the end, the same technique can be used.

For reaming in the Lathe, I made a pair of Floating Reamer holders. Parallel shank Hand reamers are held in ER25 collets, whilst M T shank reamers are held in shop made ER32 collets. If anything is off centre, the "float" allows the reamer to follow the drilling, rather than behaving as a boring bar.

Howard.