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Posted: 4/10/2014 11:29:08 AM EDT
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Can you trim a case at too much speed? For instance, I have a drill attached to my rcbs case trimmer, I use 3 way cutters. This drill is your standard craftsman plug in to the wall model, so there is no changing the speed. Can you go to fast? The cases come out looking nice, uniform and the chamfer/bevel looks great..... Any thoughts? Fixed your all caps thread title. Please don't do that. dryflash3 |
| Best to use a carbide cutter tool or sustained sharp edge and long life, and for annealed cartridge brass (C26000), 200 feet per minute speed, .028 to .013 cut per pass. This will generate a string or ringlet chip. Going too fast speed and too low cut per pass (low feed) will work harden material under the cutter and result in small fine chips. Ref. Machinery's Handbook. |
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Quoted:
Can you trim a case at too much speed? For instance, I have a drill attached to my rcbs case trimmer, I use 3 way cutters. This drill is your standard craftsman plug in to the wall model, so there is no changing the speed. Can you go to fast? The cases come out looking nice, uniform and the chamfer/bevel looks great..... Any thoughts? If it looks good your fine. I use the RCBS three way on my drill press and have yet to wear out the cutters. It makes a nice cut as long as I don't try force the cut all at once. |
| If the 3 way cutter is carbide you could run it 12,000 rpm provide you were holding it steady and feed it really fast.....but my concern would be wear out the the shaft or bearing surface of the trimmer. IF this is a lathe trimmer it is going to hard to not put side force on the shaft with a drill, whereas the powered trimmers are all lined up straight and mounted together. |
| I use a cordless B&D (lithium) screwdriver which has a slow rpm connected to a Lyman trimmer. It only takes a few rotations to trim. The rest of my shell prep I do with a Hornaday trio which has about the same rpms. With that said, I don't think to much speed will effect the trimming as its set to a positive stop and in your case, so is the chamfering and bevel however, I could see going a bit overboard with the rest of the process if you do as I in separate steps. |
| This is where buying the best tool (buy once, cry once) comes into its own. I bought a 1/2" Craftsman corded Variable Speed Drill just for such uses as case trimming. It has an adjustable stop built into the trigger so you can set it to whatever speed you need. I've trimmed countless cases with it via a Forster or Wilson trimmer, and it has served admirably in driving the various tools to uniform a 50bmg case. Don't buy cheap tools unless it's for one use. Otherwise it pays to buy quality. |
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I have found that the pressure you apply has more effect on trimming the cutter speed.
Push too hard and you start bending over the brass even at very fast speeds. Then you have a bigger deburring job to get done. Any time you would have saved by applying too much pressure to trim faster is lost. Carbide cutters are nice if you can afford them as they will last a lot longer. But I feel the your $ is better spent getting a good 3 way cutter set up... that will pay dividends for along time. The RCBS and Forster 3 way cutters are top notch. |
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Quoted:
Best to use a carbide cutter tool or sustained sharp edge and long life, and for annealed cartridge brass (C26000), 200 feet per minute speed, .028 to .013 cut per pass. This will generate a string or ringlet chip. Going too fast speed and too low cut per pass (low feed) will work harden material under the cutter and result in small fine chips. Ref. Machinery's Handbook. Cutting surface speed for brass using uncoated carbide tooling is ~800-1200SFM. Using high speed steel conservatively will still get you 200SFM. This gives us about 15,000 RPM for a .223 case using carbide, and 3000 RPM using HSS. Oviously way more is going to depend on your cutting conditions than the proper speed and feed. I trim my brass in a Wilson case lathe using an 18V Bosch drill at over 1500 RPM and it works fine. YMMV. Posted Via AR15.Com Mobile |
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