Any suggestions on how to open up a die by .001-.002"?
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Any suggestions on how to open up a die by .001-.002"?
I'm not a machinist, but - I'm guessing they will suggest lapping it, maybe?
Star dies are hardened (65 Rockwell, I think) so turning probably is not an option. If you can chuck it up really straight on a tight spindle lathe, use a toolpost grinder with just a touch of the stone on the die. If you grid any amount you will grind out the lead taper. I usually just order another die and expand my inventory. BTW, when you order a die you can get the rows of holes drilled .060 apart to cover the entire length of the rebate then peen shot into the ones you don't want to use which makes it universal for any boolit you want to size in that diameter.
Dies don't cost that much that you couldn't purchase one to suit your purposes. I have every die made for the bullet I'm going to use it on and my dies don't have the EXTRA lube holes to plug.Quote:
Originally Posted by quail4jake
Super interested in this post and I know someone is going to have a great answer for you from experience. But I would think valve grinding compound and you could lap out 1 thousandth. That’s not to far to go.
Just ordered 3 die and a top punch (from lathesmith) for my old wore out but freshly refurbished star! Should be here this week!
I have had Magma drill dies to fit a specific boolit too but then I often want to use it for something else and the holes don't line up. Peening that shot into the extra holes is a PIA and sometimes it wants to fall out so I give it a drop of locktite after peening it in.Quote:
Originally Posted by 6bg6ga
The holes will make boring it out difficult. While it can be cut with carbide the interrupted cut will chip the carbide. Same with the diamond bits available. Lapping it out will do the job or if a small enough hone can be found that will work also. disassemble and clean the die good. A wood dowel 6"-8" long that is .060 or so smaller. Cut a slit down the middle 3-4" long. Cut a piece of 600 grit sand paper as wide as the slot, and just long enough so when wrapped around dowel it is a snug fit in die. Turn about 100 rpms speed with a fast back and forth feed. ( you want to see the polish lines cross over each other not rings.) do not come off the paper on either end. Make a few strokes 6-8 like this and check size. Work slow you only need to remove .0005 on a side not a lot there. You can coat the paper with a light oil to improve finish and help keep it from loading up also. Once to size a piece of flannel or cotton in the dowel with a little flitz or simichrome to polish and your good.
That's a great idea to hone it out. Seems like I wind up doing more and more of that kind of thing the more of this I do. Don't forget to relabel the die! It's things like that which ruin my day when I can't understand why my boolits seem tight but I have the "right" die!
I've done several of them in pretty much the same manner as Country Gent described. Star dies are harder than Lyman or RCBS, so it takes a while longer, but those brands are done in the same way.
Ive found that way easier than when I had access to the ID grinders or jig grinder at work. Those machines did a good job but set up and "touch" was" harder. I normally do this with a variable speed hand drill or even a power screw driver by hand. The hone did good but having the right bar and stones and hone machine is rare. Work it with the paper and some oil, work slow and check often. I also check slugs for size rather than the die itself, I want the bullet to size don't care what the die is. this may account for some spring back or slight swelling
To open up a Star sizer die I used the same advice Veral Smith at LBT gives for opening up revolver cylinder chambers. Take a 1/4" (.250") steel rod about 6" long and split one end down about 2". Then wrap a tight bob of very fine emory cloth to fit the die. Chuck it up in an adjustable/variable speed drill and slowly turn the bob a few turns with consistent in and out movement and then check a lightly lubed boolit with a good Vernier caliper (Starrett). Once close to desired diameter, finish off with a tight bob of sheet carborundum (sp. ?) for smoothness and final dimensions. It is critical that you go slowly. Big Boomer
Country Gent gives good advice. Pay attention to the advice on measuring a sized slug to determine if you are where you need to be.
I make my own Star dies and here is a link to how I do it: http://www.bliksemdonder.com/hobbies...be-sizer-dies/