It would be a pretty good trick to make one of these without a mill. I'm not that good of a magician.
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If you could hinge the movable half of the boolit clamp at the bottom [a saw slot a link and a couple of screws] and have a handle on it in the place of the allen wrench it could eliminate a lot of screwing. Just put the boolit in and lift the handle hold pressure and drill the boolit and lower the handle and do it again.
Air to clear the chips would be good too. Like air on a scroll saw. Maybe a stiff bristle brush. Ya I know, now we are getting into the more expensive spread. When I make a shop aid or a specialised tool I try to make it so that it can not be improved upon.
Looks like it will work good, good idea. I am thinking in terms of the C&H canelluring tool type of operation.
Life is good
Well, I made a few small changes & now I have what I think I am going to call the first actual production version of this thing. It will accept boolits up to 1-5/8" long. It still has interchangeable drill bushings. It still has interchangeable boolit clamps & it now has an adjustable position top arm, so that you can dial in the exact center of the boolit that you are working with.
I made that change to the top arm for a few reasons. First, a fixed position arm would not allow you to center up for a boolit that is a few thousandths over or under the nominal diameter. Second, I was having trouble holding all the dimensions close enough to get the eccentricity as good as I would have liked. About 0.005" was the best that I did on a fixed arm. I wasn't sure that everybody would be happy with that.
I also changed the clamp gizmo around a little bit. The inner clamp still rides in a slot & still gets located with an Allen screw, but the top clamp now screws into the inner clamp with a thumb screw. I think that it's fairly quick & easy to operate. It seems to hold well enough.
This particular clamp set is sized for .30 cal boolits. By tomorrow, I should have tooling to also make clamps for 38, 44 & 45 caliber clamps.
I am currently using drill bushings that I made myself out of O-1 tool steel. I did that for two reasons. First, I was trying to keep the cost down. Second, the O-1 is actually soft enough that if you want to, you can drill it out to a different size with a good quality drill bit. That way, you don't need to wait around for me to make you a new bushing if you want to start making larger hollow points. You can just drill out a bushing that you already have. If you use this fixture in a drill press, then the O-1 should last a long time. If you try to do this with a hand drill, then the O-1 will wallow out before long & you should probably opt for a genuine hardened bushing. The hardened bushings will beat up the drills, rather than let themselves wear down easily.
I figure that I'll include 2 or 3 of the O-1 bushings with a complete fixture. I can supply genuine hardened commercial drill bushings if you want, but I just found out that the price in my catalog was old & my current cost is actually around $10.50 + shipping on a 5/32" bushing. I'd mark that up around 20% if I was going to stock & resell them. You can order them direct from places like McMaster or MSC if you want to & cut out the middle man. I'll be happy to give out the spec's. Also, the commercial drill bushings change OD as the ID changed more than a little bit. My bushing is a single OD for any ID up to 1/4 or maybe a little more if I push it. If you start using bushings with different ODs, then I'll either need to make some adapter bushings or a different top arm. Either can be done.
It turns out that it took me longer to make this thing than I had expected. I'm going to make up some fixtures to speed things along, but I'm probably going to have to charge more than the $50 I was planning on for a complete fixture. I should have the pricing worked out by tomorrow. I'll time myself again after I get the new jigs & fixtures in place.
Anyway, a picture is worth a thousand words, so here's my thousand words worth...
This shows the inside of the clamp a little better. (Those are lead chips, by the way).
I'll get this up in the swappin & sellin section of the board as soon as it's ready to sell. Hopefully that will be tomorrow. If interest in this thing is strong enough, I may go whole hog & get set up as a vendor sponsor. We'll see how it goes.:-)
...........Jim, why not use W-1 and harden it for the drill guide? It'd sure last longer then unhardened O-1 or W-1. Left untempered it'd be dang near as hard as a diamond :-) I suspect the list of best HPing drill bit sizes wouldn't be more then 6-7 so getting a chucking reamer a thou over the bit size wouldn't be a huge cash outlay. Drill it to ream and ream for a thou over the desired bit size then harden it without drawing. A drill bit isn't much for side cutting so the bushing life should be quite long. An idea anyway?
.............Buckshot
Very nice setup. It looks like you could machine the piece that holds the bullet on both ends for two different calibers. Just rotate it 180° and tighten it up to go from .44 to .38
Lay it down horizontaly and put a crank handle on it.
I don't have a hardening furnace here & I don't have any experience with flame hardening. If I bring my little muffle furnace out here from back east, where it's in storage, then I will probably start to do that.
The only reason that I'm using O-1 rather than W-1 is because my local supplier stocks O-1 on the shelf. a 3 foot length is only about $4 more than I would pay for W-1, so it's no big deal. That's a difference of about $0.05 per bushing.
There are a few reasons why that would be difficult. The biggest issue is that I mill a clearance slot between the two clamp halves, except for a small area at the bottom that acts as a pivot point. If I do a double end clamp, then I would have to come up with a different way to do the pivot point. i would also need to make the clamp longer & that would cut down on available boolit length capacity, unless I also make the center post longer. Thanks for the suggestion though. I am trying to think of ways to make this more cost effective. That was a good idea.
No problem. I didn't see how the bullets were held. The pic above helps me to visualize it.
One tool that we use to clamp multi-diameter pieces utilizes a small v-block on one side. Keeps from having to build two cavities for each diameter piece. The way that your tool is designed, the bit would have to be slid in and out to allow for the center being moved. Wouldn't be too hard for the user to notch some references in the top.
I tried a V-block & a slotted top arm. Unfortunately, when I clamped the boolit tight enough to prevent it from spinning under drill torque, the boolit got two flat spots pressed into it.
The rig above has gripping diameters that are a few thousandths over the nominal boolit diameter. This allows me to get a good grip on a raw boolit without deforming it.
i use the w1 drill rod for my chambering reamers and other bushings that require
heat treating. to keep the reamers straight ,i chuck them in the drill press and
turn them at slow speed while u heat it up to dull black red, and then shove a can of water up to the reamer. for bushings, hold the bushing with a j hook wire.
jb
HI,
Think Forester hollow pointer.
I got to working up the numbers today after I made a few of these things using more efficient jigs & fixtures. I still could not get the machine time (& therefore the selling price) down as far as I wanted to, so I went back to the drawing board. I came up with something quite a bit different. It's a lot more Spartan & not as quick to load & unload, but it falls into the price range where I wanted it to be.
This new design is caliber specific. It isn't going to fit under a drill press very well. It probably isn't going to be as durable. The concentrically can't be adjusted by the user. The only interchangeable part is the drill bushing. The only parts that are the same between this new econo-rig & the original design is the thumb screw & the spacer that goes under it. The good news is, I can let this new econo-rig go for $25 complete. Here's a first look at it. Let me know what you think.
It should be able to take up that little bit without being too far off. When the thumb screw pinches the slot closed behind the boolit, it should sort of center up a little bit. You're not going to be able to dial it in as exactly as you can on the bigger universal rig, but it should be pretty close. I'm planning on offering both versions. One is going to offer better functionality & cost more. The other will be the economy version that offers less & costs less.
It looks good Jim and price wise should be able to do the duty for the calibers we don't need to have many of HP's in stock. How would price compare between a caliber conversion kit and the smaller unit?
That's the kicker. There isn't much spread between the two right now. I need to figure out a better way to make the clamps, so I get the price down. If I had my CNC mill up & running, it would be no problem. A simple pocketing routine would get me what I want pretty quickly. Unfortunately, that machine is in storage with two blown servo drives, so I'm making these things by hand on a Bridgeport. I'm going to take one more crack at sharpening the pencil, then I'm going to post a price sheet later tonight.
Well, I finally did it. I posted these things for sale on the Swappin & Sellin section of the board. You can find that thread here - http://castboolits.gunloads.com/show...672#post764672