First real parts!

[SLK001]

On the plus side, the dial indicator showed a rough runout of about 3-5 thousandths.

That's quite a bit of runout. That much will be reflected in any parts you turn off the plate. This is the face plate you were talking about creating, correct?

You can try using a shear tool with a radius. This is my shear tool I use on outside diameters. The cutting edge is the line on the upper left. It is a vertical edge - no angle. A shear tool for a facing operation is nearly the same, except there is a 1-2" radius on that edge. Cuts with a shear tool are very shallow - DOC less than 0.001". I normally use 0.0005" DOC. The swarf from this tool is like angel hair. It is so light that it will float in the air. Use oil and a slow feed rate.

 

[n9viw]

That's quite a bit of runout. That much will be reflected in any parts you turn off the plate. This is the face plate you were talking about creating, correct?

You can try using a shear tool with a radius. This is my shear tool I use on outside diameters. The cutting edge is the line on the upper left. It is a vertical edge - no angle. A shear tool for a facing operation is nearly the same, except there is a 1-2" radius on that edge. Cuts with a shear tool are very shallow - DOC less than 0.001". I normally use 0.0005" DOC. The swarf from this tool is like angel hair. It is so light that it will float in the air. Use oil and a slow feed rate.

This is intended to be a back plate, to go with the 3JC I got from Ed. I do intend to make a face plate, but whether or not I make it out of the other slab of HRS depends entirely on how well this project goes. So far, not thrilled, but not devastated either. We'll see. For a faceplate, I probably should have started with 8x1/2 instead. I could cut the 1" plate down to 1/2" thick and leave a 1" rim, but that's a ton of shavings to make. A better idea would be to learn how to thread, then purchase, bore, and thread an existing aluminum or iron faceplate with a more common 1-1/2x8 mount.

I am well aware that the runout is excessive- I am by no means done with this, obviously. I fully intend to get it down to as close to zero as I possibly can. I was just saying that, even accounting for the roughness of the surface, I thought that amount for an unfinished part wasn't horrible, especially considering a) where I started, and b) what I started with.

I went after the high spots of the circumference with a grinder today, and got it a little rounder- at least it won't bang the hell out of my bits anymore. I'll do some research into shear bits and grind one this week. Soonest I can get back down to it for any appreciable amount of time is Saturday, so I won't know results until then.

 

[n9viw]

Well, all the tutorials I read and videos I watched showed vertical shear tools for turning, but not for facing. I wasn't sure how it would work with a vertical cutting face on a flat surface, so I figured, put a curved surface to a flat one, right?

It actually worked pretty well. The grooves are still evident, but nowhere near as pronounced- only just enough to drag a fingernail. Runout is 0.001-0.0015 depending on position, still not 100% but getting there.

I'll get back to it this weekend, and hopefully get the OD turned so I can fit the 3JC to it and spike it for mounting bolts.

 

[Charles scozzari]

Yes, I have access to something, but while I have been getting stuff done on the sly at work, I don't want to push it. Without a chuck at home, I'm pretty much dead in the water. I've already done this plate. Once I finish it (AT HOME) and have the chuck mounted, I can do more at home, and less at work.

And yes, threading will be good, as is that price, but as I have literally NEVER threaded anything, that's still an expensive mistake. And no, I have no work holding yet. I'm this close, I'm not going to bollocks it up by scrapping what I've already made to try something else that may or may not work depending on the quality (or lack) of my work.

Keep doing what your doing. Don't get discouraged. Even if it costs you more than what you could buy it for, keep going. This is the only way to learn.

 

[SouthernChap]

So let Quinn teach you.......

She's taught a lot of people via her YouTube channel, so I guess that's good advice...

 

[n9viw]

She's taught a lot of people via her YouTube channel, so I guess that's good advice...

Blondihacks, MrPete222, Artisan Makes, Jeremy Makes Things, Joe Pie, Halligan, Abom, Lucas, Clickspring, Winky, ThatLazyMachinist, AdamBurns, Stefan Gotteswinter, Make Something Cool, Phil Vanderlay, Tigermoth, IMakeStuff, RifRaf, Stumpy Nubs, Makin Somethin From Nothin, This Old Tony, Keith Rucker... good lord, is there anyone I won't watch?! All those, and dozens of others besides. By the end of my first month of owning it I'd spent weeks of hours "in the shop" and not powered up my own lathe once.

Knowledge is power, I'll take whatever I can get to keep my learning curve nice and gradual. I know I'm a moron, there's no need to go off half-cocked and untaught and PROVE it! Yes, I'm a cheap bastard, I never denied it. I'm working within my limitations (mental, personal, mechanical, and economic) until I can surpass them.

 

[SLK001]

...so I figured, put a curved surface to a flat one, right?

Your work piece looks a lot nicer. What does the front of your shear tool look like? It should have an angle ~ 5-10º off vertical, or heavily in shear. Oil, very low DOC and slow feed gives the best finish. Hone your tool's edge often.

 

[Charles scozzari]

Your work piece looks a lot nicer. What does the front of your shear tool look like? It should have an angle ~ 5-10º off vertical, or heavily in shear. Oil, very low DOC and slow feed gives the best finish. Hone your tool's edge often.

Dress the cutting edge to a half round, for a smoother finish on HR steel.

 

[n9viw]

Your work piece looks a lot nicer. What does the front of your shear tool look like? It should have an angle ~ 5-10º off vertical, or heavily in shear. Oil, very low DOC and slow feed gives the best finish. Hone your tool's edge often.

The table on the grinder is set to 10*. That angle follows all the way around that lefthand curve. The right side was left over from another project, I ignored it. I cut another one tonight for proper vertical shear, but I'm thinking of cutting a weird one, making a long diagonal vertical shear for cutting across the face, see what happens.

I think my DOC was no more than 0.003" (hard to read those small dials with old eyes)... over a half dozen passes I might have made it 0.020 total. I cut on the outfeed and used the infeed as a spring pass. Used no oil, but guess I should have, I'll try that next time. I'll get after the bit with a stone when I get home tomorrow.

As for my feed speed, it's a guess... all my feed is manual; I think there's something wrong with my clutch, because it won't tighten up at all. The clutch knob does turn when I engage the feed lever, so at least I know the key is still in there, but it's not transmitting any power to the carriage or cross.

 

[Dabbler]

@n9wiv I am a little late to this rodeo --

First let me say a fanboy thing and congratulate you on a GREAT idea for your backing plate!

It doesn't matter if your old mule has a sway back, it will still be useful!!

To minimize tear and get closer to a better finish, you can grind a high rake tool with a tiny corner radius. (I'm assuming you are using HSS bits that you have ground yourself). For facing I'd use a 8 or 9 degree clearance angle (that is the vertical clearance) and grind the left side of the tool about 7 degrees, and the right side of the tool to a point at about a 15 degree angle. I'd use a very small corner radius, and then grind a top clearance of about 20 (!!) degrees. This tool is VERY delicate, but allows you to take .0005 to .001 cuts with minimal pressure and tearing.

To get an outer edge smooth (a bandsaw will get you there, but you can save some time) You can grind a trepanning tool. The right side of the tool remains vertical; the left side is ground into a rounded shape less than the radius of the cut for clearance, and the cutting edge I'd start with about 1/8 of an inch. The top rake has to be no more than 5-7 degrees, or it will plunge into the cut and break the tool. The front clearance should be about 10 degrees. You plunge directly into the face with this tool, taking a ring of material off.

As far as the face finish is concerned, you can glue 400 wet and dry emery to a plate of FLOAT glass, and gently lap the surface, noting where the chips accumulate the fastest (the high parts of the glass). only very light pressure is needed -- This high point has to be shifted around the faceplate to minimize cutting a curvy face. The goal here isn't to get a shiny smooth surface. it is to increase the contact area by knocking down the tool marks. You only need to take a few thousandths off to get 3X or 4X contact on the back of your chuck.

I'm following your rebuild with avid interest. You are doing great!!!