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View Full Version : Truing a faceplate, getting ready to monkey with a mould



Buckshot
09-28-2005, 02:30 AM
............I'm going to be going inside a 30 cal mould to perform some alterations and have decided the 4 jaw isn't the best way to go about it.

http://www.fototime.com/51EB166DB546F46/standard.jpg

I got 2 unused faceplates from the guy I bought my lathe from, but this 10" one is one I got off E-Bay and it has 'T' slots in it. I'm going to be clamping a precision 5" grinding vise to it and figured the T slots might be better. Don't know if that's true or not. Never done anything on a faceplate yet, so it's all going to be mysterious :shock:

Oh, that black thing sticking up there from the bottom is the shop vac nozzle. Gotta suck up all those cast iron fillings. Only had to take .004" off to get it running true.

I'll post some photo's of the setup when I get that done.

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

MT Gianni
10-02-2005, 12:13 PM
Buckshot, the 429421 cleaned up great and the price was more than fair. thanks again. Gianni.

Buckshot
10-03-2005, 09:53 PM
..........Well you're welcome! Hope I don't mess THIS project up :D

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

bdoyle
10-04-2005, 01:33 PM
Buckshot,
Is your vise keyed? I would want to mount it so that it slides perpendicular to the lathe center. Sorta like a x axis on the face plate. Would make for a easier setup.

Brian

Buckshot
10-05-2005, 01:46 AM
Buckshot,
Is your vise keyed? I would want to mount it so that it slides perpendicular to the lathe center. Sorta like a x axis on the face plate. Would make for a easier setup.

Brian

.............No it isn't, and you're right that it would make it easier. LEave it loose and bring up a dead center in the tailstock and stick it in the cavity. Lock everything down, retract the tailstock and indicate it in. I'll have to think about that. Naturally I'm about done making 4 hold down clamps :D.

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

Buckshot
10-13-2005, 02:35 AM
...........I was finally able to devote some more time to this mould alteration thing. I think I may be in over my head, but we'll give it a sporting try at least. I have to work around existing features which is nerve wracking :D

http://www.fototime.com/EC6E32186093ED1/standard.jpg
http://www.fototime.com/6684CE3056F7995/standard.jpg

So there's the setup so far. I got a 5" precision vise that is supposed to be square and parallel to .0002". A quick and dirty looksee on the granite surface plate with a .0001" TI shows it to be pretty good, so far as I was able to check.

I had to make the clamps as I wasn't willing to pay what was wanted for some very similar ones. I don't think I'll be spinning it very fast. I still need to figure out something to use that's adjustable as a counterweight. Most of the vise's weight is centered one way, but a bit off in another.

I sure hope it works!

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

Buckshot
10-20-2005, 02:52 AM
http://www.fototime.com/002631191054A36/standard.jpg

Kinda dark, but I had the GC shank reading .000"/.000" except for the couple thou jump across the parting lines.

http://www.fototime.com/DACB3BECABD6531/standard.jpg

Next up was a .0005" DTI. It too was reading just a flicker on the GC shank, except for the usual bounce across the parting lines. This is a new one I had to buy with a long probe to reach into the cavities. It's not extended into the cavity here. Running on the shank.

Running the probe into the cavity, try as I might I continued to get about a .003" run out on the nose. Retracting back to the GC shank gave me the .000" reading.

http://www.fototime.com/2E52E1F832F7ACF/standard.jpg

I took the mould out and checked it on a granite surface plate. One block is .002" thicker then the other, which is no big deal. However the cavities were bored at a .002" angle in relation to the parting line. In other words the nose is .002" deeper into the block. Or setting the DTI to zero and then running it to the nose it goes down 2 thousandths.

In the other block it comes UP a thousandth :( . Anyone have any ideas?

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

bdoyle
10-20-2005, 09:36 AM
Surface Grinder? Shim up the block on the grinder and skim off the back? Failing that, place the offending base perpendicular to the vice jaw on a verticle mill. Align the cavity to the quill and mill the back. Not sure how well it would work because of tool deflection and back taper on an end mill. You only have to get one side parallel. Place that side to the fixed jaw on your vice and place a dowel pin on the clamping side. Not sure exactly what tools you have at your disposal.

Brian

StarMetal
10-20-2005, 12:17 PM
Buckshot,

Interesting, I have a Federal dial indicator just like that. Boy the thing must be over 40 years old. I was going to ask you if you heard of that brand.

Joe

Buckshot
10-21-2005, 03:30 AM
............Thanks guys, I think I'll try shimming it as what I'm using for a millimg machine would just wreak it (no doubt).

........Joe, I don't know how old it is. One of my daughter's friends' grandfather was a machinist and he gave me that (it's a back plunger) and a broken Starret dial caliper :D

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

Doughty
10-21-2005, 10:36 AM
Buckshot,

Where are trying to go with this? I believe you said you were trying to make some alterations. What are the alterations? Increase diameter? Change band width? Change nose profile???

Old Vic

StarMetal
10-21-2005, 11:25 AM
Well Buckshot, mine is a backplunger too, they must be identical. Imagine that.

Joe

lar45
10-22-2005, 03:06 AM
I mounted a drill press vise on a spindle arrangement to try boreing some 70 cal molds. What I used to balance it was WW ingots with holes drilled in the center, then bolted to the otherside of the face plate. I poured a bunch of them thin and varying thickness' so I could mix match until it ran smooth. I'm sure you'll come up with something prettier. Just thoughts.

Buckshot
10-22-2005, 11:36 PM
Buckshot,

Where are trying to go with this? I believe you said you were trying to make some alterations. What are the alterations? Increase diameter? Change band width? Change nose profile???

Old Vic

...........Increase nose and band width.

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

Linstrum
10-24-2005, 05:22 PM
Hi, Buckshot, how ya doin'? To get the parts set up so they are square and true, I would do it by shimming them up to compensate for the out-of-square and misalagnments that were machined into the parts. I have used paper, aluminum foil, tin can sheet metal, and more stuff than I can remember to get parts mounted up so that they are square with the world, and some instances it took me all day to set up for a half-minute cut. For parts that are made so that they can't be clamped down with bolts or held in a vise, I have cast them into a block of Cerro Bend (new name is Cerro Safe) and then clamped onto that or machined the Cerro Bend/Cerro Safe surface to be square. Cerro Bend/Cerro Safe is a real trip to machine because the chips melt while you are machining it and can jam up the tool. It even melts if you hit it with a hammer or center punch and is actually quite dangerous because little droplets of it shoot out at high velocity and can cause serious and permanent eye damage. I have some Cerro Bend/Cerro Safe tattoos in my hands from working with the stuff 35 years ago. Anyway, I have machined similar things like that by shimming the parts up until I got them square and true. You'll get it!

Doughty
11-01-2005, 11:52 AM
Buckshot,

How are you coming along on this project?

Buckshot
11-02-2005, 04:27 AM
Buckshot,

How are you coming along on this project?

I have been successfully ignoring it, which doesn't do much for the guy who wants it done :D. I don't know why I'm having such a problem getting motivated about this thing. It's not like digging a ditch or doing your income taxes, but it just gives me a headache. I should (as a matter of character) just buckle down and do it, huh?

The 2 tools have been ground for the internal work, it's just the blocks and the cavitie's alignment issues.

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