Adventures in top punch making (Long)

[badgeredd]

PS while is may piss of some purists... running machine tools is alot like sports.. there is alot of 'feel' involved.. A gentle touch is a good thing to have for machine work..

The "gentle touch" is precisely what makes a good machinist stand out from the adequate ones.

Edd

[oldtoolsniper]

Based on the information I have read here I tried thread cutting oil for drilling and taping some holes in plate steel. I was surprised at how much better the correct lubricant works for the job it was intended for. I always just grabbed whatever can of 3 in 1 oil was closest to the hole I was drilling. Instead of chips I got nice long tendrils of wire to whip around the drill bit. Did you know they are sharp?

[RP]

Well how about this I got a peice of brass stock that was all ready round chucked it in my drill press and with a file drill bit I used for a cutter and some sandpaper i maded a few diff top punches I have no way to shape them to fit the boolit so I just made them to cover as much as the boolit as I can. But its not always saving the 10 bucks to buy a top punch but to have what you need sooner and sometimes find out your wasting your time. And lets face it people that reload dont like to spend money if they think they can save some its in our nature.

[oldtoolsniper]

Someone on this site suggested coating the tip of a cast boolit with Vaseline and then putting JB Weld on the end of your close to fit top punch. Use the boolit to form the JB Weld on the punch end to fit your boolit. I have not tried it yet but it sure seems like it would work.

[Hang Fire]

If anyone is considering picking up one of the little cheap Chinese lathes, they take a bit of finagling and modification, but they are not junk or a toy and can be made to turn out some decent work.

Here is the place to go, as these guys have done it all and once in the group, they keep the emails flying with constant information and tips for using and improvements.

http://groups.yahoo.com/group/7x12minilathe/

Sometime back I picked up one of the 7x12" lathes and a little milling machine. I have been rather amazed at just what one can do with these small machine tools that only cost a few hundred bucks each. No matter who labels them, they are all basically the same tools, just some with more free accessories etc.

Here is the basic lathe setup I got on sale for $490.00 with free shipping, note the accessories, a face plate, tail stock chuck, plus fixed and traveling steady rests.




And here at link is a few of the modifications I have done to them both. http://hstrial-rchambers.homestead.c...hine_shop.html

[oldtoolsniper]

So if I am making a .452 sizing die do I buy a reamer or drill bit in that size or is this done with a boring bar?

[leftiye]

O.T. sniper, Yes.
You try to find a drill that is going to make a hole a few thou. (maybe 5) smaller than the reamer you plan to use (a .451 reamer in this case). You first drill with a 1/4" drill, then the intermediate size, then ream. And then you finish the last thou with sandpaper (600 grit) on a dowel. If you can see your way clear to get a set of plug gauges , do it. They're really nice for determining when a hole is the right size. (clean the hole of chips, or abrasives before checking for size)

Drills and reamers in a very close set of sizes can be had from MSC.

[JIMinPHX]

If you are just going to do one sizing die, then a reamer is a good way to go. If the size that you need happens to be a standard size, like a 5/16 (.32 cal) or a #3 or a letter D or a 5mm etc., then the reamer can be had for a reasonable price. If it is an intermediate size, you can still get the reamer specified to a decimal size, but it will cost a bit more. Reamers in this size range are happiest taking around .003"-.010" off the diameter of a clean drilled hole that is on center. If you decide to go with a reamer, then we can talk about all the little tricks to make them run best. You can get a good finish right off the reamer & not need to use abrasives for finish afterword if you do it properly. I ream right to finish size while holding better than half a thousandth all the time like clockwork.

If you are going to do a bunch of sizes, then it makes sense to do them with a boring bar because with a single bar, you can get a whole range of sizes. Before purchasing the bar, decide what sizes you intend to eventually make so that you can choose the best bar for the job. Bars that are more than 6 diameters in length are generally hard to get good size control & finish with. You don't want to just get the longest & skinniest bar that you can find if you don't need to, because it will be hard to work with. There's a lot more to it than that, but that is a good general rule of thumb to start with. Again with a boring bar, if you do everything right, you can get good finish right off the bar & not need to go to abrasives afterwords. The abrasive trick can save you in the event that you are having trouble getting good finish with the bar. It's easier to get good finish with a reamer, but it can be done with a bar too.

[oldtoolsniper]

I am nowhere near that level yet but as I progress I am realizing what it takes to do some of this stuff and the expense involved. In learning all of this it just makes me appreciate more what members from this site are willing to do to support each other.

When I was stationed in California the big thing was low rider cars; I have no use for them but I could appreciate the talent it took to create one.

[JIMinPHX]

Running a reamer properly is not that hard. You just need to know a few things about using it properly like RPM, feed rate, lube, proper way to hold the tool, & proper way to prep the hole for the reamer.

Boring bars take a little more craftsmanship, especially when the hole is more than a few diameters deep, but with proper care & methods, they work quite well.

Reamers in the $15-$30 range are suitable for making dies. Cheap "braze-on" boring bars are acceptable & can be found for under $15. The nice bars to have are the indexable carbide insert bars. Small, good quality, indexable bars (1/4", 3/8", etc) in kits with inserts can be found on sale periodically for around $100 if you know where to look. It's possible to find a lower quality indexable bar for $50, but they can be harder to get good results from on a deep hole & generally do not support the insert as well, so tool life is not as good.

Suitable reamers can be found, starting on page 218 of the big book here - http://www1.mscdirect.com/CGI/NNPDFF?PMPAGE=1

Some nice Cleveland brand reamers are on sale on page 7 of this month's sale circular, but only some sizes -
http://www1.mscdirect.com/CGI/NNPDFF?PMCTLG=04&PMPAGE=1

Nice Circle brand boring bars are in that same sale circular on page 18. They are around $75 for the bar & $7 each for inserts. 2 inserts should last you for many dies if you treat them properly. I've done about 4 or 5 dies with one of the 1/4" bars & I'm still on my first insert. Page 17 has a 12 piece set of braze-ons for about $110.

[Buckshot]

............Remember, a drill bit is NOT going to give you a round hole. I also leave a thousandth after boring to bring a die to size via honing. To make a Lyman type die I do this:

1) Centerdrill
2) Drill 1/4" pilot hole. Use the very best quality bit you can afford. You want the hole as straight and round as possible. I use a Guhring Tin coated parabolic. It has a 140* flute angle, below:



This bit has been stuck through God only knows how many die body blanks, and I mean BUNCHES of'em. They run over $24 each and I got a plastic cassette of 10 of'em for $20 or 30 bucks off E-Bay about 4 years ago. I've been making Lyman and Lee type dies for 4 years and this is only the second bit out of the packet!!!!!!!!!!!!!!

3) Step drill, after determining which reamer you have that will leave you somewhere around .020" short of final size.

4) Once ready for the reamer, the die is marked (so it will be returned to the collet in the same place) then the lube holes are drilled through the body.

5) The die body is replaced in the collet and then reamed. Drilling the lube holes upsets metal into the die bore at break through, and the reamer is not sensitive to them and cleans it all up.

6) Check the bore with (minus) pin gages.

7) Bore to about .001" short of final. I use the solid carbide bars made by Circle C. They use carbide inserts, below:



I have the 3/16, 1/4, 3/8, and 1/2" bars. MSC currently has a couple of them on sale. The 1/4" is a very usefull size as the 3/8" has a minimum bore of .438", while the 1/4" bar is .300". They're good for a 10x stickout if you use the DOC and feed suggested (or a couple passes). These came from MSC and they currently have a couple on sale. At the sale price you're basically paying for the supplied inserts and getting the bar for free.



For a boring bar of this OD, it's sticking out pretty good

8) Hone to size. I used to use diamond paste and brass barrel laps. Diamond paste is expensive, and it's hard on the brass laps ($). Now I use silicon carbide paper on aluminum rods turned to usefull sizes, and slit with a jewelers slitting saw to hold the paper. It takes longer but it works.

..............Buckshot

[oldtoolsniper]

I need to get a bigger lathe and a lot more cash! You guys spend my money faster than my X-wife!

[leftiye]

It's probly already been mentioned, but the metal used makes a big difference in the finish that is possible to obtain. O1 toolsteel is fantastic for a wide range of possible uses, for good finish, and toughness (they even make ball bearings out of it). If you're just cutting mild steel, the finish isn't gonna be as good. Hence, polish to size. For boolit sizing dies, and case sizing dies, mild steel does work. In the case of the boolit sizing dies, it also lasts very well because the wear only progresses a thou or so before the as cast size is reached, and it takes forever for the wear to progress up the length of the hole.

[dicko]

[QUOTE=oldtoolsniper;517981]Adventures in top pu€nch making. Having two craftsman 109 metal lathes of which I have no idea how to use. I decided to make a top punch for a swc cast boolit.

Very fair comment, all of it. But really, it is not all that hard to machine simple tools decently. It does help to get some instruction, because everything is a mystery until you learn enough that it is no longer a mystery. I was lucky, I guess. I had something like 400 hours of machine shop at school. It came in handy years later when I wanted to do some of my own gunsmithing, and even handier when I ended up doing the gunsmithing for a local gunshop.

But it was still a learning curve. My school machine shop was not enough. The one thing that needs to be understood is that a lathe is not a production tool, and all machining and tool making is time consuming and can't be rushed. It is therefore true that, if you are going to count your time, you will never make anything as cheap as you can buy it.

There are two reasons for making things, for the hell of it, or because its the only way to get it. I make all kinds of stuff, gun parts, tools, jigs for making parts and tools, bullet sizing dies, top punches, and loading dies for straight wall cases.

Working to one thousandth is not difficult. In fact close sliding fits have to be a lot closer than one thousandth. Just by way of example of the sort of things you learn, you can't set work dead to centre in a three jaw chuck because the way they work makes some inaccuracy inevitable. The jaws close anything up to two thousandths off centre. The three jaw chuck is a convenience tool for quick chucking of round stock, and for work that will be machined at one setting.

For setting dead to centre you need a four jaw independent chuck. But bear in mind you can't set ordinary bar stock to centre because it isn't perfectly round to start with. Where the four jaw shines is setting precision ground stock, or machined work dead to centre or a measured amount off centre, for eccentric work. Using a dial test indicator, I routinely set to two tenths total indicator reading (per revolution) which is one tenth off centre. That still isn't dead centre but is a lot closer than you'll get with a three jaw and closer than you'll ever need for gun work and most anything else.

But setting to centre isn't the half of it. The sheer precision and variety of accurate work you can do with a four jaw chuck and DTI is amazing. I seldom use a three jaw.

Running a lathe isn't rocket science, just needs practice.

[Ruger45]

ROFLMAO!! I've been a machinist for over 20 years and that tale you told was funny! Now you have a small idea of why I got paid $20 an hour to apparently sit on my backside doing nothing. Just remember....anything is fairly easy if you know what you are doing.

[SlippShodd]

I don't know why it never occured to me to make my own sizer dies and top punches. There's a 14x40 lathe in my shop, as well as a little HF 10 incher for making the little pieces that I forgot to make before I zeroed in the real project on the big lathe. One of my hobby businesses is building and repairing pool cues, so for most of its life, the big Lincoln lathe has been a wood turner. Certainly it's done a fair share of metal work, turned scads of replacements for broken firing pins, reloading machine parts and what not, but typically a secondary application. Which means that the metalworking tools have been somewhat, um, neglected. I was frustrated recently when I took on two new calibers to cast for, then couldn't find sizing dies for my RCBS LAM locally, or from the perpetually out of stock online stores. Then I stumbled on this old thread last week and I haven't been the same since.
BTW, that original post was damn funny and I've passed on "X=24" to a friend of mine who teaches math and science to 5th-graders in San Antonio. This year Idaho's test scores will finally trump Texas.
So I had to go buy a stick of 3/4 steel and start tossing it in the recycle bucket 3 inches at a time. Actually I only screwed up the first one and that's because I over bored it. Right there in my Machine Shop Practice books is that table about expected drill bit oversizing, but I referred to that only after witnessing the practical application. I'll hang on to it 'cuz I can still open it up for another caliber down the road. I had to hacksaw the workpieces off the stock because I also forgot that parting tools need a relief angle ground into the face; something I don't need for wood. A quick touchup on the grinder fixed that. I also spent a goodly amount of time resetting some tool heights (I have a quick change toolpost and lots of toolholders), again something that is more critical with metalworking than it is for wood. And I spent a goodly amount of time this morning futzing with realigning tool holders and such before I bored the piece.
Ah, the new boring bar. I discovered I didn't have boring bars small enough for this project a couple nights ago. So I spent a fair amount of time online searching for something suitable and praying I could find a local vendor so I didn't have to wait an eternity for it. I wasn't finding what I wanted, then I remembered that right around the corner from where I used to work was a local company that builds custom carbide tools. So I went to Micro-100s website and found exactly what I was looking for and then some. Next morning just after they opened, I slogged across their snow and ice parking lot, held the door for the company's owner and bellied up to the counter. When a nice man asked if he could help me, I started off with, "I was on your website at 2:00 a.m...." at which point 3 people in the office started laughing and from way back in the corner I heard, "This can't be good!" Anyway, I walked out with a sweet little boring bar with a minimum bore of .20". One of the dies to be made has to be .225 and I think I can pull it off with this bar. If not, they have one that will go .180 and actually bores deeper than the one I bought. It bored my first die out to .3105 without a hitch, leaving me with half a thou to hone out for .002 over my .309 bored Ruger .308. I pushed a boolit through it dry and it looks very promising. Just a few finishing touches and then I'll start on the .225 die tomorrow night maybe. The top punch was way too easy, even if I did over-engineer it like most things I do.
So thanks to all who participated in my re-education of forgotten skills. In the process I discovered again my love of self-sufficiency in all possible aspects, as well as a boatload of tools I'd forgotten I had.
Not that that will impede the purchase of even more. Like reloading, these tools are saving me money.

mike

[largom]

Now you need to make your own custom seating dies for those fat cast boolits.

Larry

[NMLRA Guy]

My son worked in a shop that had three-jaw and four-jaw chucks. These were big enough that a chain-fall had to be used to change them out. Ergo, they learned to use the four-jaw chucks rapidly...much much faster than changing chucks even if they were slow. After a bit of use, they learned to do it nearly as fast as centering in a three-jaw

[Awsar]

if it was easy everyone would do it.yes much respect for a true machinist.
i am not one but i like to pretend
been making a few top punches out of aluminum its easy to work with and works.

[Del-Ray]

Kind of makes me feel better about my "abilities".

I'm making top punches on an old engine lathe in our shop. The chuck jaws juuuuust barely close tight enough to hold the 1/2" rod I start with. And there's no fine adjustment for the..... "back and forth" action? "In and out" has a fine adjustment though. Thankfully. Really puts a beautiful finish on the edge that touches the bullets.

Looks like I need to go to that place down the street with the books in it for some learnering.