Neck turning - "wobbly" drill driver

[Link]

Thank you all for the wisdom and advice. I don't have a ball micrometer to measure the actual case neck thickness before and after - closest I have is the Redding Case Neck Wall thickness guage, but I have always had my suspicions on how accurate it can actually tell the thickness - been using it basically just as an indicator of high/low spots, since I cannot see a reading change before and after turning necks.

I clamp my cutter to my bench and then manually manoeuvre the screwdriver to do the cutting. After cutting, the redding tool mostly shows a slight improvement in terms of needle movement and consistency on the dial at least, so I always assumed that the wobbling wasn't detrimental. But I couldn't help doubting myself, so I'm glad that I asked the question and got the answer.

Thanks again for all your comments on the topic.

I thought they said let both the cutter and driver float?

 

[P1ZombieKiller]

cutter can float as the brass wobbles..... doesn't matter if the driver is mounted or not.
I use a dewalt drill.... it's not "mounted", but the body of the drill never moves....
You can see by @Dusty Stevens pic that his motor is mounted (or at lease so heavy no way it moves).

 

[dgeesaman]

Hi

Hopefully this is not the most stupid question ever asked...

I use a little hand-held screwdriver (Bosch IXO) and the bottom part of the Lee handheld trimmer to secure and turn the casings.

This little screwdriver has a visible "wobble" when its turning, and although it seems like this is not transferred to the neck area once it is on the mandrel in the cutter, I was wondering if this is something that I should try to prevent by using either my hands or by using a better quality driver?

With my K&N and power screwdriver setup I notice the wobble. I don’t fight it. It tends to be worse if I push the case all the way to the bottom of the U-slot of the shell holder. If I tighten it down with the case in the dead center of the shell holder there is no wobble.

Now that I think about it a piece of carefully placed piece of tape might consistently eliminate the wobble. But I’m still holding within a tenth on the necks even with the wobbling.

David

 

[Uncle Ed]

There is a difference between the wobble caused by the octagon shaped bit holder and the wobble caused by a off center case in the Lee case holder.

Many of the Lee aluminum shell holders are crudely made, and simply do not hold the case centered and they add to the wobble.
Many of the aluminum shell holders have burs where it clamps to the case rim. And this adds to the wobble problem, and sometimes you just need to order a new one and hope it will work better.

These crudely made aluminum shell holders were not a big problem when trimming the cases by hand. "BUT" can cause a problem when the shell holder spins in a drill or screw driver with a off center case.

This posting should be divided into the cheap bastards Lee case holder section. And the cost means nothing for a shell holder neck turning section.

I know what section I belong in because when I pass wind it sounds like a silent dog whistle. (tight ass humor)

 

[Brians356]

While you have it in the holder, use a trimmer that stops on the shoulder, spinning the case longer than it feels like the cutter is cutting by about 5 seconds, chamfer and debur.

Boyd, I assume your case advance depth stop contacts the end of the neck. So, to get consistent incursion into the shoulder, especially when advancing it quickly as described, have you previously trimmed neck lengths by indexing off the shoulder?
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[BoydAllen]

Boyd, I assume your case advance depth stop contacts the end of the neck. So, to get consistent incursion into the shoulder, especially when advancing it quickly as described, have you previously trimmed neck lengths by indexing off the shoulder?
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Actually, I have gotten pretty good at eyeballing how far the angled part of the cutter needs to cut into the shoulder, and only trim after turning. The way that I have learned to expand my necks gives no additional runout over the out of box cases. and I do slow a bit when I get to the shoulder, and stop when I see the full width of the angle on the shoulder. I use an old Sinclair turner that has a wide angled part to make a rough cut at about .009 ( neck thickness) and then just touch that with my finish cut. I realize that some will be uncomfortable eyeballing this, but it has worked for me for a long time.

 

[Brians356]

Actually, I have gotten pretty good at eyeballing how far the angled part of the cutter needs to cut into the shoulder, and only trim after turning. The way that I have learned to expand my necks gives no additional runout over the out of box cases. and I do slow a bit when I get to the shoulder, and stop when I see the full width of the angle on the shoulder. I use an old Sinclair turner that has a wide angled part to make a rough cut at about .009 ( neck thickness) and then just touch that with my finish cut. I realize that some will be uncomfortable eyeballing this, but it has worked for me for a long time.

You must have better eye/hand coordination than I have. Do you make a shoulder incursion with the Sinclair, or do that only with the final tool? Is the Sinclair a simple hand tool or a lathe type?
-

 

[BoydAllen]

You must have better eye/hand coordination than I have. Do you make a shoulder incursion with the Sinclair, or do that only with the final tool? Is the Sinclair a simple hand tool or a lathe type?
-

Simplest model they ever made. When it comes to athletics, I would have to say that I was standing behind the door when that sort of coordination was handed out, but I do just fine at other tasks. Let me tell you a little story. Back when I was doing some carpentry, I could lay out a line on the back of a sheet or plywood with a straight edge and one of the old cheap BIC ballpoint pins, that has a fairly wide line for its type, and using my circular saw and a hollow ground plywood blade cut the line so that half of it remained...freehand. It takes practice, concentration, good tools, and believing that you can do it.

 

[Straightshooter1]

You must have better eye/hand coordination than I have. Do you make a shoulder incursion with the Sinclair, or do that only with the final tool? Is the Sinclair a simple hand tool or a lathe type?
-

I use the Sinclair tool too . . . which is held in the hand (see here). Since I make sure the cases are all the same length with the same shoulder measurement before I turn them, the stop gets me to the right place on the shoulder. It's a pretty simple operation.

See results here:

 

[Brians356]

Simplest model they ever made. When it comes to athletics, I would have to say that I was standing behind the door when that sort of coordination was handed out, but I do just fine at other tasks. Let me tell you a little story. Back when I was doing some carpentry, I could lay out a line on the back of a sheet or plywood with a straight edge and one of the old cheap BIC ballpoint pins, that has a fairly wide line for its type, and using my circular saw and a hollow ground plywood blade cut the line so that half of it remained...freehand. It takes practice, concentration, good tools, and believing that you can do it.

That's impressive! I suspect maybe youth was a positive factor. I don't have the steady hands I once had, or they visual acuity. My OptiVisor is never out of reach.

What I was driving at was the Sinclair could be used for a slower, accurate shoulder cut, then the rapid lathe tool advance is less critical. But now I'm overthinking - again.
-

 

[Brians356]

I use the Sinclair tool too . . . which is held in the hand (see here). Since I make sure the cases are all the same length with the same shoulder measurement before I turn them, the stop gets me to the right place on the shoulder. It's a pretty simple operation.

Nice. When it's right, it's right.

Another way of (over)thinking about it, FWIW, is that the distance of the shoulders from the case bases could be all over the place, but if the necks are trimmed indexing off the shoulders, the neck lengths should be as near equal as possible, and ditto the turner's shoulder cuts.
-

 

[rwj]

http://www.xxicsi.com/neck-turning-lathe-complete.html

Yup... initial cost is a bit high, but it’s more than paid for itself! Plus it’s saved me from experiencing a lot of pain in my wrist and shoulder that will never be “right” again...

 

[243Lapua]

Just let it wobble. I also a started with a electric screwdriver. Invest in a small lathe and better shell holders. PMA, Sinclair, 21st sell excellent shell holders. I made my own neck turner out of a gear electric motor added a coupler and a 1/2" chuck. I turn necks, size cases, clean primer pockets, clean the inside of the necks. It's very adaptable.

 

[heydogman]

I took a 6" length Snap on wobble joint extension and cut off the 3/8 socket that attaches to your air wrench so It can be chucked in a drill press. Mounted the case holder in a bit socket attached to the extension. Mounted the cutter in the machine vise sandwiched between 1/2 hard rubber.
It worked but I went back to using my wobble drill.