Am I a fool to buy this mill/drill?

In practice I've only needed to mill a few common angles and a set like this was good enough:

jsw

A smaller vise can be handy, especially if you can clamp the smaller vise in the larger vise as this will allow you to cut/drill compound angle holes at some cost saving over a compound angle vise. Note that you can do the same thing with a slotted right angle block with some loss in tool/table clearance but some additional cost savings.

You will of course need some way to set/check the angles. While somewhat expensive I find one of the small 3inch/75mm magnetic sine bars to be very useful. Also get a space block set or use feeler gages to set.

It all depends on the size/kind of the parts you will be making. [inch] examples of magnetic sine bar

space block set [same as jo blocks for home shop use at 10% of the price] ?PMAKA=630-4050&PMPXNO=950511&PARTPG=INLMK32 right angle plate

Unka George (George McDuffee) .............................. The past is a foreign country; they do things differently there. L. P. Hartley (1895-1972), British author. The Go-Between, Prologue (1953).

Of course -- but I didn't have any that were short enough, and since I had to cut them down anyway, I chose to make suitable studs that could be used with the clamping kit, too. (I couldn't go out and buy short bolts, either, because it's Easter, and Norway is officially Lutheran Protestant Christian. Easter being a big deal for the Christians, the whole country comes to a complete halt for five days. Suits me fine: I have five days off to tidy up my home workshop and get this mill set up and working.)

That's clever! You can still use the swivel base if you need to, since you haven't modified the vise in any way. How did you hold the bolts when turning them down and threading them, without damaging the existing thread?

-tih

I did it in my Taig which has a 3-jaw with aluminium jaws. I tried with two hex nuts etc. but in the end I just gripped them and ripped them. The advantage - no damage to the threads. The PITA - the alu jaws do not grip well enough to allow threading. On anything.

Hmm ... turn a ring for the OD of the aluminum jaws (or for steps which you have turned on them to make them look like standard chuck jaws) and expand the jaws into it to leave a grip diameter just a little larger than as small as you can. Then drill the jaws (expanded into the ring) to the tap drill size and start a tap into this on the lathe with the rear end held in line by the tailstock center. Once the tap is started, remove the chuck from the lathe and grip it in a vise and finish tapping the jaws as deep as is reasonable for holding your threaded stock. Then you can loosen the chuck (after removing the ring) and easily thread the screw stock into it and clamp down on the thread having much more grip surface.

Or -- if you don't have soft jaws, take some aluminum of say 1" OD (assuming your thread size is 1/2" or less), center drill it and drill to tap size on the lathe while holding it in the 3-jaw chuck and tap as before. Then remove from the chuck, and put a slitting saw in your mill and cut a radial slit from the OD to the center hole. Now, put it back in the lathe chuck, orient the slit directly opposite one of the jaws, screw in your screw while it is loose, then tighten the chuck to close the slit and grip the thread.

Enjoy, DoN.

snipped-for-privacy@athene.hamartun.priv.no...

I've gotten slightly better results with a threaded rod coupler and a hex nut. It still doesn't run true but there's more to grab.

If the job is worth it I make a cup out of 1" drill rod and thread a hole in the bottom, starting the thread on the lathe and finishing it with a tap, which cuts much better when it has only a little to remove. This is faster than lathe threading to final size.

This one here is tapped 1/2-13. The bottom of the cup is barely two threads thick or about 4mm and that has proven strong enough to turn down a pile of stainless steel bolts for Segway battery mounting studs. The head tightened within the cup or a nut on the outside keeps the bolt from wobbling.

I made them to use in 5C collets, and short enough to tighten the bolt head with a wrench. If you make them for a chuck a pipe cap turned cylindrical on the OD might be better to leave room for a socket wrench inside. I'd thread the cap onto a nipple to chuck it and cut both the OD and the thread for best concentricity. Face off around the hole afterwards so the bolt doesn't tilt when tightened.

jsw

Yikes! A bit of an overkill for just two bolts.

I can see that one. Presumably steel jaws will grip into the aluminum outside and prevent rotation. I found that *anything* held in the aluminum jaws was not held strongly enough for cutting outside threads. Perhaps it is a function of the chuck tightening mechanism, too (two tommy bars rather than a key). With smaller stuff (my gnomons) I got around it by using the

1/8" collet. But forgret anything over 1/4".

A quick, simple and less accurate way to do that is to wrap a piece of sheet aluminum into a tube that doesn't quite close.

Cut a piece of 1/16" sheet the length you want and 3 times the diameter. Lay the sheet across opened vise jaws, center the rod and hammer the sheet into a U. Use the vise to close the sides nearly parallel until you can clamp the U and rod in the vise with nearly half the rod diameter above the jaws and knock the edges in further, then finish the tube by squeezing it tighter around the rod with the jaws, working all around. It may come out better in a smooth-jawed milling vise.

jsw

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Yes -- it makes more sense with more to do -- but consider future use and mark the jaws in slot number order so you can re-use them again at need. (Oh yes -- you can also turn the jaws around and use the other end for a different special holder.

How were you cutting the threads? Given that the lathe was a Taig, I suspect that you were using a die. Single point cutting (in multiple passes) the thread using a geared lathe feed generates a lot less force, so you can cut threads without the workpiece slipping like it was for you.

BTW Aluminum jaws gripping an aluminum "threaded collet" such as I described above will grip better than smooth steel jaws on aluminum -- though most steel jaws are not smooth. :-)

But if you bore a set of the aluminum jaws to a close fit on the collet you just made, you will have better grip -- especially considering that aluminum on aluminum tends to gall, improving your grip. :-)

And -- you can take some valve grinding compound, and roll the OD of the collet in that (with some force), so when the jaws are tightened, the jaws grip a lot better by embedding the compound in both the jaws and the OD of the collet.

Longer Tommy bars will give more leverage. Make them of a larger diameter steel, with the ends turned down to fit the holes and to bottom with very little turned down diameter left extending. Perhaps make them of drill rod, and harden and draw appropriately. You don't want them too hard (brittle), but you want them harder than the supplied state of the drill rod.

But be careful to not make them too long, or you will deform the holes in the chuck body and the scroll plate. Consider that my Taig

3-jaw only has the holes in the scroll plate, and I need to grip by the chuck jaws to keep it from turning. (Hmm ... I probably should drill holes for the Tommy bars in the chuck body to go with those in the scroll plate.) But yes -- the chuck key is giving you a *lot* of leverage for tightening the scroll plate.

BTW -- how well lubricated is the scroll plate? The less you have to fight friction in the plate bearings and in the scroll to jaw tooth engagement, the more of your force will go towards tightening the chuck jaws on the workpiece.

Good Luck, DoN.

that is cute as hell, but $160??

that Enco set for $29.95 looks like a great deal. thanks!

It's tricky to set up an insert vise on those thin angle blocks in a milling vise. Unless you can c-clamp the blocks to the fixed jaw there are too many loose parts to hold snugly in place as you tighten the jaws. The thicker ones I suggested will stay in place by gravity, their problem is excessive height if you have to stack the notched ones.

Alternatively you can clamp a guide to the fixed jaw or to a large slotted angle bolted to the table and use the thin angle blocks to adjust it to the desired angle.

jsw

Is that a problem with steel jaws for later use?

I need some lapping compound for another purpose (lapping dovetails) so I shall go hunting this week. It is always so much fun watching the faces of the shop assistants when you ask for something like that...

[...]

I put wooden handles on the wood lathe ones.

I was kind of concerned - I can make the bars bend in my hands alone. Lord knows what would happen with more leverage.

A squirt of graphite as per T-nut post. But I guess it could be better. It is hard to know without having any standards to compare.

Not really. If the jaws are hardened steel, they will simply crush the compound deeper into the collet's OD. If they are mild steel, you will get a better grip than you would otherwise have. Note that Albrecht make a drill chuck which has diamond impregnated jaws for avoiding slipping on hardened and ground tool shanks (typically milling cutters, as standard drill bits have shanks of mild steel for easier gripping, while the flutes and tip are HSS.

And watch them try to come up with obscene interpretations of what you are asking for? :-)

Your wood lathe has that kind of chuck?

Then you need hardened and drawn drill rod, with the larger diameter just outside the hole minimizing the bending. If you just harden it fully, it will be too brittle and be likely to break of right at the chuck body. So after hardening (for an oil or water hardening drill rod -- be sure to use the proper quench agent for each) you can re-heat it to a lower temperature -- at a guess about 450 F would be reasonable and then leave it to cool normally. Air hardening drill rod is difficult to get to less hard than your original quench produced, so that should be avoided for this purpose. However, it is nice when you are experiencing warpage when you quench because the air cooling is a lot more gentle.

Did you work it in fully after squirting it? BTW -- Teenut worked with serious sized industrial machines, and might have given different advice for lubricating a chuck as small as a that used on a Taig. (That advice might have been "Get a bigger machine" :-)

A pity that he is no longer with us.

Enjoy, DoN.

Or -- you could use a sine bar and a cheap set of Chinese gauge blocks to set the angle of the vise, then once it is clamped firmly, slide the gauge blocks and the sine bar out from under it. Typical sine bars are 5", larger ones 10", but I have one 2.5" one which is nice in a small machine vise. (Of course, you have to adjust the size of the gauge block stack for the length of the bar.) But the sine bar is a real winner when you need an angle which would require several angel blocks to build up the proper angle.

Or -- you could clamp the workpiece close to the right angle (set by a protractor or the like) and place the sine bar and the gauge blocks on top of it in reverse and use a dial test indicator to tell when you have the right angle (zero change when the angle is right).

Yes.

Enjoy, DoN.

The 2.5" sine bar sounds like a good idea. The shortest one I have is

3" which is also the width of the bed of the vise and it slips off too easily.

I don't think I've ever had to mill a flat surface at an angle that wasn't an integral number of degrees, usually a multiple of 5, so the angle block set has been more useful than my gage blocks. I've used them with a sine bar only to measure the angle of a conical taper.

The tooth cutter for the tractor steering sector was ground for a 20 degrees pressure angle with a correction for side clearance, but I set that up in a 3-way-swiveling Univise.

jsw

Take a single parallel and lay it down on the clean bed of the vise, so your 3" sine bar footprint won't cause problems.

I've used the 2.5" sine bar in my shaper's vise to make a piece of aluminum have half the included angle of an Acme thread to use it in a toolmaker's vise for setting the half-angle on my surface grinder for making a couple of Acme threading tools. The toolmaker's vise was mounted on a sine plate to set the relief angles for the particular thread pitch being cut -- reversed for the internal threading tool of course.

O.K. I don't have one of those.

Enjoy, DoN.

They are thin sine bars like (A):

were a waste of money. They are almost too tall for my milling vise anyway.

...

The Univise was adequate for my gear cutter but it would be difficult to set close enough for a precision Acme thread. I bought it to use as the base of a Quorn-style tool holder.

There are half and quarter degree plates available for the angle block sets.

jsw