help with mendrell

[Califo]

I have a rookie question, I know you may have an answer. I find that when I turn slimlines, the blanks are usually tight slipping onto the mandrel. Do you normally do anything to avoid this? Today I was working on slimline that turned out better than I expected and when I tried to take it out of the mandrel, it was stuck to it. I had to ruin the pen in order to take it out. Could it be glue/epoxy, dust, the tube diameter narrower than the mandrel? Either way, how do you avoid this? This is the second time this has happened and othertimes I am able go get the finished blank out but it is tight.

Any help is appreciated.

 

[wyone]

do you use a pen mill to trim the ends? If so the shaft of the pen mill will normally clean out anything inside the tube. The only time I ever had issues getting on and off the mandrel was when I had used the mandrel for pens before and had some CA on it. I used some steel wool and polished it up and it worked fine after that. Every once in a while I still do that as I think it helps to keep things clean. I did have one blank stuck once, but I just left off the extra bushings and nut and slid the live center up against the mandrel, turned the lathe on the slowest setting and simply reached down and grabbed the blank and slid it to the end. Then I turned off the lathe and had no issues getting it off.

 

[GaryT45]

Try sliding a bare brass tube on the mandrel - it should slide on and off easily. If it does not, the problem may be with the mandrel. Then glue that tube into a blank, and try sliding it on and off the mandrel again (to see if you are getting glue inside the tube). Then mill the ends, and try sliding it on and off again.

 

[heritagebob]

after squaring the ends,, take a small round wire brush and clean the insides ( each end ) of the brass tube,, this will remove any epoxy or CA left inside the tubes,, that's what I do and have no problems

 

[Califo]

Thanks. I like the wire brush tip. Much appreciated to all

 

[beck3906]

I use a gun bore brush chucked in a drill. Let it turn about 2-3 times.

Just be careful with any method as you can easily take off brass on the inside of the tube resulting in a loose fit of your components. You'll need locktite or epoxy to hold them in place if you do.

 

[randyrls]

Marco; Another possibility is that there is a burr on the end of the brass tube created by the pen mill. You can remove this with a champhering tool. This is used by ammunition re-loaders. Get one of these from a local gun shop, or from Arizona Silhouette and others.

 

[beck3906]

I use a gun bore brush chucked in a drill. Let it turn about 2-3 times.

Just be careful with any method as you can easily take off brass on the inside of the tube resulting in a loose fit of your components. You'll need locktite or epoxy to hold them in place if you do.

 

[Crashmph]

After using a pen mill, you can sometimes get a bur created on the lip of the tube shrinking the diameter of the tube at the ends. I use a reaming tool to clean up any burs on the ends of the tubes after a pen mill as required.

 

[Sawdust1825]

Your pen mill is setting you up for failure. The diameter is so close to the pilot diameter you get a thin but not obvious burr that when you tighten it down on the pen mandrel it forces or crushes it down on the threads of the mandrel. Two options as I see it. Get a Whiteside pen mill or a Routa-a-Burr. I have one from my metal working days and they are sweet for deburring. Here is a link for one. Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies

 

[sbell111]

Your pen mill is setting you up for failure. The diameter is so close to the pilot diameter you get a thin but not obvious burr that when you tighten it down on the pen mandrel it forces or crushes it down on the threads of the mandrel. Two options as I see it. Get a Whiteside pen mill or a Routa-a-Burr. I have one from my metal working days and they are sweet for deburring. Here is a link for one. Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies

I use a chamfer tool that I bought from Midway USA. It works great.