Neck Turning Speed

[skeeljc]

What is a good speed to turn case necks? I intend to hold the case in my lathe and use a K&M neck turner.

 

[D Coots]

180

 

[RegionRat]

Machining Handbooks show the recommended cutting speeds for materials and alloys in terms of feet per minute at the surface, which can be converted to RPM based on the diameter. There are typical values for properly sharpened High Speed Steel and also Carbide, etc., that can be different.

Here is the catch. Those values are good, but they assume the work piece is held conventionally and when we have a pilot, we have to worry about galling on that pilot. That can mean turning at the recommended cutting speeds with the caveat that your pilot may overheat sooner so the real speed is the limit that your pilot and lubrication can attain.

You will have to adjust your speeds to your own processing within those recommendations and according to the cutter material and dressing (right kerf angles) and lubrication for the pilot.

Here is an example of a table that shows brass. It seems a little higher than what I have in some texts and lower than others, but like I said earlier, these are just guides and not rules of physics.

https://littlemachineshop.com/reference/cuttingspeeds.php

 

[Falfan2017]

I’ve found with a low powered handheld battery drill/screwdriver it really doesn’t matter much as long as you keep the mandrel cool

 

[JimSC]

I use a 180 RPM battery operated screwdriver and lube the mandrel with Imperial

 

[dkhunt14]

I use a gearmotor with a speed control. I like around 100 RPM. It seems to cut good and helps keep the heat down. Matt

 

[17TACnes]

I use a Black&Decker battery operated screwdriver, it is light weight, has low speed and low torque and it is still working great going on 10 years now.

 

[SmokinJoe]

I use a 175 rpm worm drive gearmotor, cuts good and very quiet.

 

[jepp2]

What is a good speed to turn case necks?

I'm certainly not an expert, but I use the max speed on low range on my cordless drill. 450 RPM tends to give the best surface finish.

Before I started turning necks, many cautioned about heat build up of the turning mandrel and steps to avoid that. Don't know if it is the lube I use (Bootleg) or the 21'st Century expander and turning mandrel diameters, but I have never had that issue. At first I would check it every 5 cases with an IR thermometer and never changed a bit. I've turned over 1K now, many different diameters, same result.

 

[rwj]

180 RPM works for me...

 

[Ccrider]

I use a Hitachi li ion handheld on low. 200rpm. Works fine. No heat build up.

 

[Straightshooter1]

I'm certainly not an expert, but I use the max speed on low range on my cordless drill. 450 RPM tends to give the best surface finish.

Before I started turning necks, many cautioned about heat build up of the turning mandrel and steps to avoid that. Don't know if it is the lube I use (Bootleg) or the 21'st Century expander and turning mandrel diameters, but I have never had that issue. At first I would check it every 5 cases with an IR thermometer and never changed a bit. I've turned over 1K now, many different diameters, same result.

Likewise, I use my variable speed cordless drill with a max 600 RPM and that works well at that speed for me . . . in the Arizona winter when my work area in the garage is pretty cool. My turning mandrel and cutter are carbide in my Sinclair tool (it doesn't generate heat like a steel) and I use no lube as there's no heat issue. When my work area is really warm, like in the summer) I do slow the speed down by about half, otherwise it does heat up some. I like the higher RPM for a nice quick finish.

Like mentioned in a previous post here, the issue is keeping things from heating up so that there's no galling or seizing up onto the mandrel. If properly lubed, one could turn using up to 4000 RPM, or. . . if you just want to be really safe, you can just turn it by hand.

 

[SmokinJoe]

skeeljc asked for some pictures of my wormgear case turner, so here they are along with my experiences. This is the 4th case turner I have had and I have prepped thousands of cases while shooting benchrest and high volume varmint shooting. The turning machines that I bought were all helical gear units, first one from Bruno's a long time ago, the second from Darrell Holland and the third from Don Neilson (Pumpkin). They all use Forster collets to hold the brass. A couple of these were just too noisy for me, and all three had so little internal friction that it was hard to get the collet tight on the case rim. So I decided to put my own unit together and based it on the 175 rpm wormdrive gearmotor in the picture, knowing that the wormdrive would be quieter and have more internal friction to help with chucking. I bought the chuck from Don Neilson and had it fitted to the gearmotor from Grainger. It was quiet and did a great job but still didn't have as much friction as I wanted, so I added the clutch and it is as good as I could hope for now. Hope this helps some of you.

 

[Bill Norris]

I use this Hammerhead cordless screwdriver. It has plenty of torque and the battery will allow for turning 50 cases or more between charging.