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View Full Version : My ES PC fixture system. Nail head method.



totalloser
02-22-2014, 11:35 PM
Not original I have seen reference to this process before, and I explained this in another thread, but here's how I did mine:

Lay out 3/4" on center grid on 1x3 or 1x4 block, stack on another block and predrill two holes for screws and screw them together.

Drill the grid (on mill or drill table for flatness) for stainless roofing nails and then pop them back apart. Slip in a piece of aluminum flashing or pop can aluminum cut to the same or slightly smaller size and run the screws back in to sandwich the aluminum.

Tap in all the nails so that they punch though the aluminum, and then run a couple screws into the sides so that the heads are sticking out enough that a wire wheel can clean them up regularly.

Don't go smaller than 3/4" on center or the ES charge will likely not work properly. And for the noobies- you think your hot rod MSD ignition can make your hair stand up... well you have no idea. You will NOT touch the nails twice when they are energized. [smilie=1:

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The pictures show a mildly refined version of my first try. The refinement is a button head screw run sideways between the flashing and block to energize flashing, and the elimination of flashing hanging out. The purpose of this modification was to provide a clip lead that is easily cleaned (bench grinder with wire wheel) which also cleans up the heads every two or three uses. The flashing became a pain to keep clean, the screw head is easy to clean up.

I have found a few things in this process I have not found mentioned before: First, I hate wearing gloves so I dust my fingers with PC from the booth (cat litter box bottom) before handling boolits. Second, I found that when I have a batch intransigent (usually cold) boolits that don't want to take a coat, I make a pass with the low pressure blow gun with the ES energized and then make another pass with the ES gun and the coating becomes *much* more consistent.

For a while I was not acetone washing, but did some basic math and realized it took less time to wash, then it did to fiddle with random problem boolits.

Make four if your time is valuable to you. Two per batch, and two out while baking. Otherwise you will be burning your fingers instead of letting them cool while loading up the next batch. Much less hassle to pop them off a cool block, plus you won't have a hot one fall into the PC on the block.

Larger calibers are quite easy to balance on the heads, but 9mm is problematic. Especially with RN 124gr and similar. Just too long on too small of a head, and the cut sprue usually sticks up just enough to make them unstable. So if you are considering getting into this and looking at molds, 9mm would be the one to get HP. .40 and .45 are easy to balance. 9mm is not. Or at least not for me.

This process can easily be used to make point up for HP, just run the nails all the way through. I am using HF yellow and HF red to make orange for cheep. Yellow is a pain by itself, but the red helps it bond pretty well, and this is all single pass. It takes about 5-8 minutes to prep and coat two fixtures, and I am baking 15 preheated or 20 not preheated at 400 based on the cheapo toaster setting, which appears to be more accurate than the oven thermometer I had hoped to use.

This gives me about 10 min of foot tapping, so I cast alongside the PC setup which doubles the overall efficiency of the process and eliminates foot tapping.

Beagle333
02-22-2014, 11:46 PM
That is a pretty neat system! Impressive! :-D

totalloser
02-23-2014, 12:06 AM
Unlikely to be as fast as piglet or other tumble methods, but they come out pretty for pretty cheap. I went this way after being dissatisfied with the non-stick foil method. And I went to that after being dissatisfied with pan lube, for which I amended with fixtures to eliminate boolit handling.

Mostly I'm just lookin' to streamline it for anyone considering the ES PC process. No fear of highish pressure loads in polygon barrels for me anymore! One of the main reasons it made sense on paper is that I have too much pure lead and not enough coww to alloy it for the handguns my wife and I would like to shoot. With ES PC I can sweeten the pure with very little coww and get away with it.

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Plus I'm a special kind of cheapskate. :roll:

mdi
02-23-2014, 12:16 PM
Any problems with the wood in the oven (burning/charring)?

HDS
02-23-2014, 02:06 PM
Unlikely to be as fast as piglet or other tumble methods, but they come out pretty for pretty cheap. I went this way after being dissatisfied with the non-stick foil method. And I went to that after being dissatisfied with pan lube, for which I amended with fixtures to eliminate boolit handling.

Have you tried using a heat gun on the bullets as they are drying, keep tossing them about on the pan before going into the oven. I read that someone did this and eliminated the sticking issue.

totalloser
02-23-2014, 02:42 PM
Charring: Technically yes. I cranked up the heat due to a faulty oven thermometer. Wood starts to char around 450 and the thermometer was reading 350 as the wood was charring- I assumed the thermometer was right and the cheapo toaster oven was wrong. Since then I have placed trust in the toaster setting and run it at 400 with NO charring, so for practical purposes the answer is no.

As to heatgun tumbling, this is a different issue. Powder settles on the fixture below the nails and when hot it is fairly tacky and gooey. If a boolit falls off a nail, it sticks to it. Usually they can be fished out and the PC is still OK, but other times it either leaves PC on the boolit (big nasty chunk) or pulls some off the boolit. Either way back into the "to be melted" pile. This has been a pretty minor problem which only shows up when I pull hot fixtures. And the bulk of this problem is when dumping them hot. A second set of fixtures eliminates this since you can load another batch without waiting for the first to cool down.

Once a PC has baked on, most of the boolits are more stable, but there are always a few that are loose on the nail. These ones are the ones that will fall into the fixture if handled roughly. But since the majority are stabilized by cooling PC around the perimeter, the rate of fall offs is *way* less than before they are baked with similar handling.

I did consider heat gun preheat when having trouble with cold boolits and cold fixtures, but the blow off and another ES pass noted in my OP is WAY faster for me, and probably more effective.

PS I pinned down the problem with 9mm. The nail heads I am using are almost the same diameter as the 9mm boolits. A key component to a smooth process is to have the nail heads about .020" (or more) smaller than the boolit. Practice has improved projectile placing though. I posted this when I had just got it functional. I will be building two more fixtures specifically for 9mm by cutting .020" +- off the nail heads on the lathe.

If the nail heads are not smaller than the boolit, PC flashing will be on the base, and the boolits will be more challenging to get off. I found a good trick for that too: Dead blow or rubber hammer. Virtually no force is needed- just sweep it across the boolits and they fall right off. PC flashing on the fixture means more frequent passes with the wire wheel too- every other batch or so.