Making a double R/B mould in the lathe.

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homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Making a double R/B mould in the lathe.

Post by homebrew .357 »

Hi, yep I`m at it again, This has been done before I know, but this is just my take on it and the way I did it because I only have my lathe, True, my son has my drill press.
So the lathe is my drill, Mill and every thing else. The two mould blocks, (I`m useing Aluminium )are trued up in the four jaw chuck square and flat and the inside of the two moulds is picket. The to halves are clamped together and set in the chuck end on for drilling a pin hole off center for a locating pin near the bottom, this is so the mould will have a register to close in the same place every time. I return to the top face and give it a skim to make sure it is true. Now marking out for the round ball cavitys it is the spruce cutter on top that is the datum point for where they will go, so two holes in the cutter are where the center line for the r/b cutout in the two halfs of the mold. Mark from one end only for the to r/d centers so both sides are the same. Some pics so far, :wink: homebrew.
Attachments
the blocks trued up in lathe with bottom pin drilled and marked for r/b cutting.
the blocks trued up in lathe with bottom pin drilled and marked for r/b cutting.
finnishing moulds face with the r/b halfs cut in.
finnishing moulds face with the r/b halfs cut in.
Last edited by homebrew .357 on Mon Jul 22, 2013 2:47 am, edited 1 time in total.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Making a double R/B mould in the lathe.

Post by homebrew .357 »

Hi, getting a head of myself here, making the r/b cutter. In the past I have just ground a half round profile to the size I wanted, not good, so this time I thought get it right for a nice round ball. I set up a piece of s/steel in the four jaw chuck and turned it down to .437", the r/b size I wanted, then chamfer the face 45% and parted it off close to the end about .020" in from the chamfer, I had a small round disc .437". A small length of square mild steel was cut and a slot cut in one end to fit the disc in tight, and then soldered in place. the disc is ground to close to half It`s size on the right side, leaving a half profile on the left side for cutting out the profile in the ali blocks, this is ground sharp on the edge.
The in cut is done with the DTI on the topslide and the cross slid is set for the ball rim to the center line and clamped up. now have a nice r/b mould to fit my barrel. :lol: ,and the pics, cheers, Homebrew.357.
Attachments
the DTI set up for the in cut, to .2185" half the size.
the DTI set up for the in cut, to .2185" half the size.
Cutting the r/b profile.
Cutting the r/b profile.
the home made cutter.
the home made cutter.
again
again
Last edited by homebrew .357 on Mon Jul 22, 2013 2:45 am, edited 1 time in total.
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Making a double R/B mould in the lathe.

Post by homebrew .357 »

Just a bit of finishing of, cutting the slots for the handles. when all is done a got clean with acatone and use a candle to soot up the mould ,ready to go. Hope this helps some one learning how to do bits on the lathe, cheers homebrew.357.
Attachments
drilling the pin holes on the side, the clamp is for a counter weight.
drilling the pin holes on the side, the clamp is for a counter weight.
Milling the slot for the handles.
Milling the slot for the handles.
The job done, a new double round ball mould.
The job done, a new double round ball mould.
It open and closes nicely.
It open and closes nicely.
Soot add from a candle so it casts nicely.
Soot add from a candle so it casts nicely.
Last edited by homebrew .357 on Mon Jul 22, 2013 2:53 am, edited 1 time in total.
JackF
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Location: Caldwell, Idaho

Re: Making a double R/B mould in the lathe.

Post by JackF »

Beautiful job and write up. :) :)

Jack.
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steamin10
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Location: NW Indiana. Close to Lake Michigan S. tip

Re: Making a double R/B mould in the lathe.

Post by steamin10 »

Nice! But the real test is a good mic to see how round it really is. Perfection the goal, but seldom attained.

I have bought all my Lymon molds, so I salute your efforts.
Big Dave, former Millwright, Electrician, Environmental conditioning, and back yard Fixxit guy. Now retired, persuing boats, trains, and broken relics.
We have enough youth, how about a fountain of Smart. My computer beat me at chess, but not kickboxing
It is not getting caught in the rain, its learning to dance in it. People saying good morning, should have to prove it.
hammermill
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Location: pendleton or

Re: Making a double R/B mould in the lathe.

Post by hammermill »

i will have to think this thru i have always made my own cherry. may have to try this aproach. thanks x
homebrew .357
Posts: 214
Joined: Thu Aug 11, 2011 2:32 am

Re: Making a double R/B mould in the lathe.

Post by homebrew .357 »

Hi guys, Yes your right, the proof will be when I have a casting session, but making the cutter that way should make a nice round ball. But the main thing is to make sure the two halfs line up true, the other one I made was off center and .450"diameter.
I seam to make the cart before I git the horse, I made the r/b mould first before I made the barrel, bore ended up being .440", was smaking those balls in with a sleghamer.
Have made four moulds so far, one was for .30 cal,no good, but I`m learning and if you look hard at this one you will see I`m trying a long spruce in one and short in the other, just to see if one shoots better than the other :lol: Homebrew.357.
PS, Looking for some more steel for another barrel, well I`v sill got all the bits from the last one, and I know my mistakes :idea: .
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steamin10
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Location: NW Indiana. Close to Lake Michigan S. tip

Re: Making a double R/B mould in the lathe.

Post by steamin10 »

Ha! Thats not called a failure, its called research and devopment. Most people dont tell on themselves. I find it most encouraging that the honesty puts you on my hack level of successes. I dont always get it right either, but the persuit, failure and final success is all part of the learning process. Much diferent than the falsely assured with 'I can' statements of wishful performance. You can say 'I did', a whole diferent universe. Play on and have fun.

Nice pic series too.

For the cutter, My choice would to be having a little flat pip when the sprue is cut, and not having any tail. Early molds had a separate cutter that left a tip on the ball, blamed for a certain percentage of innacuracy.
Big Dave, former Millwright, Electrician, Environmental conditioning, and back yard Fixxit guy. Now retired, persuing boats, trains, and broken relics.
We have enough youth, how about a fountain of Smart. My computer beat me at chess, but not kickboxing
It is not getting caught in the rain, its learning to dance in it. People saying good morning, should have to prove it.
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