Making screw jacks - Lesson in taps and dies

[Christianstark]

Get the Starrett. It is the best. Or make one.

$57.50 delivered Thursday from Amazon. Done.

 

[Christianstark]

I like this style. Mine is a starrett from a garage sale.

I do as well. Will be keeping my eyes out for a nice handle type in the future. I think the 93C will serve well for the majority of what I do...but may eventually need more leverage down the road.

 

[WobblyHand]

I do as well. Will be keeping my eyes out for a nice handle type in the future. I think the 93C will serve well for the majority of what I do...but may eventually need more leverage down the road.

93C has a divot in the handle so you can use a spring loaded tap guide. If you tap the hole immediately after having drilled it, your tap will be perfectly aligned. Works both on a mill and a lathe. Makes tapping a lot easier.

 

[Christianstark]

Side conversation - Don't want to start a whole new thread for this, but I recently was very humbled while trying to make two small RC parts for my dad. Drilling holes on my 1340GT did not work out well at all. tiny drills went in the center, and was about a mm off center in less than an inch.

I'd like to make a sensitive drill attachment that I feeb by hand, but not everything I have seen is for a mill, and not for a lathe where the chuck can free spin. Something like Joe Pie has, but I am not confident I can make one yet. Id buy the chuck and straight arbor, but not confident I could drill the sliding fit part for the tailstock.

 

[Christianstark]

93C has a divot in the handle so you can use a spring loaded tap guide. If you tap the hole immediately after having drilled it, your tap will be perfectly aligned. Works both on a mill and a lathe. Makes tapping a lot easier.

I want to make one of those for the experience, but not sure I am there yet.

 

[mikey]

everything I have seen is for a mill, and not for a lathe where the chuck can free spin. Something like Joe Pie has, but I am not confident I can make one yet. Id buy the chuck and straight arbor, but not confident I could drill the sliding fit part for the tailstock.

A number of options, the first of which is to own a Sherline lathe that would do this without any effort. Sort of makes you rethink the "biggest you can fit or afford" thing, doesn't it?

Practically speaking, there is absolutely no reason you cannot take a typical sensitive drill chuck that is commonly used for this job on the mill and use it on the lathe. I've done it and it works fine. I use it to drill out carburetor jets. I'm not sure if this is the thing that Joe refers to as being $700-900 but they are not that expensive if that is what he's referring to. Still, they do cost but if you find a used one in good shape then they're nice to have. I have two, a Royal with a tiny Jacobs chuck and an Albrecht. I like the feel of the Royal but I prefer the Albrecht chuck; might have to switch them one day.

If you want to make the sleeve that Joe shows, its just a "simple" reaming job. Reaming accurately is not difficult if you pay close attention to your choice of drills. I'm attaching something to read that might help. The thing to note. Use two drills to drill your hole: the pre-reamer drill you plan to use right before your reamer and a drill one step smaller than that one. Face the work clean, spot it lightly and then use that one step smaller drill to bulk out the hole. Do not use pilot drills (that will drift), do not push the drill; feel it and keep it cutting continuously. Clear chips often and keep the drill lubed. When you get to final depth, don't dwell in there. Now come out and chamfer the hole and go in with the pre-reamer drill. Again, lots of lube and this time the drill will go in easily so pecking is not necessary. Make a single pass with this drill, don't go in and out. Now clean out that hole really well with compressed air and a brush or whatever you need to be sure there are no chips or debris in there; you want it clean. Check to be sure there is a good 30-45 deg chamfer, then ream it with a lot of lube. I highly recommend you keep your speeds low enough so you can feel the reamer cutting; for me, this is in the 120-200 rpm range. I set up a carriage stop so I don't hit the bottom of the hole with my reamer (dulls it quickly when you do this) and make a single pass. When I hit the stop, I stop the machine and withdraw the reamer. Blow it clear and you have a hole.

 

[Christianstark]

So I received the tap wrench today. To be honest, I was thinking to myself "how much better could this be over the other T-handle wrenches I have used in the past?" The answer, just after holding it and clamping a tap? ORDERS OF MAGNITUDE.

 

[woodchucker]

So I received the tap wrench today. To be honest, I was thinking to myself "how much better could this be over the other T-handle wrenches I have used in the past?" The answer, just after holding it and clamping a tap? ORDERS OF MAGNITUDE.

yep, having been using a 2 jaw for a few years, I would not go back to a 4 jaw. Remarkable difference.
BTW General makes the same wrenches. You don't have to give up a leg for one. But I understand, that red box makes us feel good.

 

[Christianstark]

yep, having been using a 2 jaw for a few years, I would not go back to a 4 jaw. Remarkable difference.
BTW General makes the same wrenches. You don't have to give up a leg for one. But I understand, that red box makes us feel good.

I may buy a General one in the 'A' size to replace my junker that came with my junk tap and die set.

 

[WobblyHand]

yep, having been using a 2 jaw for a few years, I would not go back to a 4 jaw. Remarkable difference.
BTW General makes the same wrenches. You don't have to give up a leg for one. But I understand, that red box makes us feel good.

Do you happen to know the part number of a C sized tap wrench by General, with the two jaws? Need a quality 93C like tap wrench.