# MT 6 1/2 One Piece Dead Center



## erikmannie (Jan 5, 2021)

I am making some 6 1/2 Morse Taper one-piece dead centers for my PM-1660TL lathe.

Here is part of the way through the first one, which is cold rolled 1018 steel:


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## erikmannie (Jan 5, 2021)

I finished the 60° taper cut. I used the compound for this.


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## erikmannie (Jan 5, 2021)

Parting it:


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## erikmannie (Jan 5, 2021)

Here it is, on the right:


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## erikmannie (Jan 5, 2021)

And at the bottom:


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## erikmannie (Jan 6, 2021)

I am going to make another one tomorrow out of 4140 prehard.

I learned some lessons from the first one:

(1) all of the work can be done in one chucking!

(2) I almost made this one too short. There was nothing gained by starting with a short workpiece.

(3) the way I went about getting the angle on the one above was not scientific. I cut an angle that was purposely too small, & then I gradually increased the angle until I got it.

(4) I have a plan to use a dial indicator to set the angle perfectly. This is something that I saw on YouTube.

(5) I had to rush at the end because I didn’t want to leave it chucked in overnight. I didn’t like the way that I had this one chucked up. I was only using half the depth of the jaws. I felt like this might damage my chuck if I left it in there overnight.


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## ddickey (Jan 6, 2021)

Why not put the MT6.5 in the spindle and finish the point? That way you'd have zero runout. Rough it in the chuck and finish in the spindle.


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## tq60 (Jan 6, 2021)

Turn between centers so no parting

When taper is bone insert and make point

Sent from my SAMSUNG-SM-G930A using Tapatalk


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## erikmannie (Jan 6, 2021)

Really great tips! I am going to use both those tips starting now with the 4140 prehard.


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## ttabbal (Jan 6, 2021)

I played with this method a little and found it pretty easy to use.


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## erikmannie (Jan 10, 2021)

I worked on one more of these today which is made out of hot rolled 1045 steel. 

I have the angle set correctly (using the compound). I just need to bring down the diameter more, & make sure that I get the best finish that I can get.

A friend of mine is coming over tomorrow who has worked with taper attachments for a long time. I have still never tried my taper attachment, but he is going to get me started.


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## erikmannie (Jan 10, 2021)

It should go without saying that I used a live center for my work. I moved the tailstock away to take measurements before I took this photo.

I did this all in one chucking. I used carbide inserts to rough it down, & HSS when I got closer to the final dimensions.

I will do the base (a cylinder of reduced diameter) & the tip (a temporary 60° tip) after I fine tune the taper.

I will have to part it at the end.

Everyone can see that I am having issues with the finish. I can get a great finish with my A6 carbide inserts if I take an (oil cooled) .075”-.100” cut (off of the radius) at 380 RPM using the power feed at .004” per rev.

Using the compound for the taper, I never could get a good finish. I used HSS because I had to be as quiet as possible after 7 PM (reduced RPMs) because my neighbor is a complaining crybaby. I will be able to go back to the carbide tomorrow morning to bring the taper down to final dimensions (another .050” off the radius).

Does anybody have any recommended starting settings for using the carbide insert to take .050” off of the radius?


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## erikmannie (Jan 10, 2021)

After this one, I’m going to make 2 more. I will be using the taper attachment. I am sure that I will be able to get a better finish with the power feed.


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## erikmannie (Jan 10, 2021)

I have done all that I can do with this one until I put it in the spindle nose and cut the 60° tip. 

I have my compound set now to the correct MT 6 1/2 angle, and I have still not tried my taper attachment. I don’t want to lose that setting until I am sure that I can get the taper attachment going.

The dead  center on the left is the one that I just made. The sleeve on the right is from the factory.


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## macardoso (Jan 10, 2021)

Great finish for hot rolled IMO. Using something like stainless or 4140 prehard will yield a much better finish but be a lot harder to machine down. All a question of how much you will use this.

Since this isn't hardened, you'll wear the tip over time. I'd give yourself as much length on the tip as you can tolerate so you can skim it many times to recondition the point (as needed).


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## erikmannie (Jan 23, 2021)

I made my third one of these today. 

Everything was wonderful in the first 2 photos, but then tried to chuck the front in order to face off the nubby left after the parting operation.

There wasn’t enough of a shoulder to grip the work so, long story short, I had to finish this stubby dead center with (1) a flap disk on the bottom, (2) wire wheel, (3) 80 grit and then 220 grit sandpaper, & finally green Scotch Bright.

At least I got rid of the chuck marks.


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## erikmannie (Jan 23, 2021)

Here it is finished. I am kicking myself to have finished it with my welding tools. Such a poor, scratched finish.

This is 1045 steel. I wore out four A6 carbide inserts making it. It took me 7 hours from raw stock to this:


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## 7milesup (Jan 23, 2021)

Looks good.  I don't understand the comment about the welding tools though.


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## davidpbest (Jan 23, 2021)

Too bad your chuck doesn't have 2-piece jaws - you could have made soft jaws to hold the tapered part when you turned it around.  Looks like you got what you need out of it though.  Nice job.


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## erikmannie (Jan 23, 2021)

7milesup said:


> Looks good.  I don't understand the comment about the welding tools though.



I was considering a flap disk, wire wheel & sandpaper “welding tools”. 

I HATED that scratched finish so I chucked it up at the bottom and fixed the finish with files & 80 grit emery cloth. Well, time to clean ALL the grit off the lathe.


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## erikmannie (Jan 23, 2021)

So here is what I have so far. From left, stock PM adapter sleeve with MT4 dead center, 1018 steel first try, 1045 steel from today, another 1045 from last week (I still need to cut the 60° tip), and 4” 4140 prehard round stock for the last one.

I’m going to force myself to try my taper attachment for the chromoly one. I have been afraid to use the taper attachment; I was afraid that I won’t be able to re-engage the cross slide after disengaging it to use the taper attachment.


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## erikmannie (Jan 23, 2021)

davidpbest said:


> Too bad your chuck doesn't have 2-piece jaws - you could have made soft jaws to hold the tapered part when you turned it around.  Looks like you got what you need out of it though.  Nice job.



I couldn’t figure how one would mount a taper in a two jaw. 

Why do people buy 2J chucks? Why not just take two jaws out of a 4J?


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## davidpbest (Jan 23, 2021)

2 piece jaw - not 2 jaw.  Here is a lathe chuck with 2-piece jaws:






And here is an example where the top part of the jaw has been replaced with an aluminum substitute that can be machined to any configuration necessary to securely hold the part:






Here's another example of a soft jaw machined to precisely fit the OD of a shallow part that would be impossible to grip without profiled soft jaws:


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## erikmannie (Jan 23, 2021)

davidpbest said:


> 2 piece jaw - not 2 jaw.  Here is a lathe chuck with 2-piece jaws:
> 
> View attachment 352230
> 
> ...



Thank you for the comprehensive answer. Those pictures appear to be from a very clean, professional operation. 

I happen to have a 12” TMX 2-piece jawed 4J independent chuck en route to me now. I hope to one day be able to afford the soft top jaws for it. $200 for a set of 4 soft top jaws:









						TMX Soft Top Jaw for 12" Independent / Scroll Chucks, 1pc, 3-884-312P
					

TMX Soft Top Jaw for 12" Independent / Scroll Chucks, 1pc, 3-884-312P




					www.smalltools.com


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## davidpbest (Jan 24, 2021)

You will find much more affordable jaws (for your chuck and vises) at Monster Jaws.


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## SLK001 (Jan 24, 2021)

When you make these, make them in pairs.  Hold the stock for the first taper in the 3-jaw and cut the taper to within 0.005" of the final size.  Now, remove the chuck and insert the first taper into the spindle, then cut the second taper to within 0.005".  Flip them around again, then cut to final size.  Now part the piece and cut the points.  Using the spindle keeps the runout very low (lower than the 3-jaw can).  If you desire to use your welding tools, drill a center hole and make yourself a "negative center" so that you can mount your tapers between centers and finish off your tapers.


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## erikmannie (Jan 24, 2021)

SLK001 said:


> When you make these, make them in pairs.  Hold the stock for the first taper in the 3-jaw and cut the taper to within 0.005" of the final size.  Now, remove the chuck and insert the first taper into the spindle, then cut the second taper to within 0.005".  Flip them around again, then cut to final size.  Now part the piece and cut the points.  Using the spindle keeps the runout very low (lower than the 3-jaw can).  If you desire to use your welding tools, drill a center hole and make yourself a "negative center" so that you can mount your tapers between centers and finish off your tapers.



I like the first idea better, but I would like to make a 60° negative (i.e.”cup” rather than “cone”) center (two deep cup-types pictured below). 

In fact, I think the dead center pictured above that I had planned to cut to a 60° tip will now be drilled or cut to a negative center. I could either use a large center drill or use the compound to cut a 60° internal taper. 

I would be inclined to choose the center drill, like you said. I wonder what these “negative bull nose” types are used for.


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## erikmannie (Jan 24, 2021)

Here is the last one. I decided against a negative center, and went for a classic 60° tip.

I had this in the tapered spindle nose when I cut the taper.


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## erikmannie (Jan 24, 2021)

I took off my D1-6 4J chuck (for the first time, it needed some coaxing). I tested all of my 6 1/2 MT stubby dead centers & they all fit perfectly.

In order to test the fitment, I recut the 60° angle on all of them while they were in the spindle nose. Here are some pictures of that.


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## erikmannie (Jan 24, 2021)

I put on a 14” face plate. I’m gonna face it.


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## erikmannie (Jan 24, 2021)

This is my first experience with cast iron. I know to clean the grit & cut it dry.

.010” DOC, 70 RPM, .005” feed, A6 carbide.


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## erikmannie (Jan 24, 2021)

Here is the faced face plate. I faced .010” and then another .007”.






The cast iron makes such a filthy mess! I am going to remove this face plate & clean behind it before I use it.


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## AlanB (Jan 25, 2021)

And such a lovely sound when cutting.


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## erikmannie (Feb 4, 2021)

I am making the last one of these today. I am starting out with this 4” round bar of 4140 chromoly prehard.


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## erikmannie (Feb 4, 2021)

The deepest facing cut I can make is .050”. I am at 380 RPM, .005”/rev feed, cutting dry, with a tired A6 insert.


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## erikmannie (Feb 4, 2021)

I locked the carriage, introduced oil-based CF because I saw sparks, took a .010” pass & got this finish which encourages me to put on a fresh insert.


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## erikmannie (Feb 4, 2021)

I think everybody would agree that this tip is in need of replacement:


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## erikmannie (Feb 4, 2021)

I forgot to lock the carriage for this lubricated .015”pass (still at .005”/rev), but the fresh insert made the following improvement. If you look toward the center, it looks like I should choose higher RPMs. My machine jumps from 380 to 620, though, because I chose the easy setup of an RPC over the variable RPM that I could have had with a VFD.


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## erikmannie (Feb 4, 2021)

I am facing the other side now .015”. I turned the RPM up to 620 and I got this:


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## erikmannie (Feb 4, 2021)

900 RPM, lightly lubed .020” cut produced this finish, & this new insert tip is already showing wear.


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## erikmannie (Feb 4, 2021)

Here is the taper in the spindle nose. I measured as carefully as I could and I came up with .0240”/inch of (radial!) taper.







The precision ground, female taper in this spindle nose is 2.60” long.

This reducing sleeve came with the lathe. The precision ground, male taper on the sleeve is 3.10” long.






The precision ground male taper extends .572” beyond the spindle nose:


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## erikmannie (Feb 4, 2021)

The male taper is 3.10” long, but it is sticking out .572”, so only 2.53” of the sleeve is engaged.

I measured the female taper as 2.60” long, so I calculate that .070” of the smallest diameter section of the female taper is not engaged by the reducing sleeve.

I will now measure the diameters on the factory reducing sleeve that actually see engagement.


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## erikmannie (Feb 4, 2021)

The top of the sleeve has an OD of 2.7670”, and the bottom has an OD of 2.6250”. 

So it tapers .1420” over 3.010”, for a radial taper of .0236”/inch.


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## erikmannie (Feb 4, 2021)

When I measured the interior earlier, I came up with .0240”/inch. When I measured the exterior, I came up with .0236”/inch.

The contradiction here is that few weeks ago I chucked up the factory reducing sleeve and, using a toolpost-mounted dial indicator, I came up with .0256”/inch taper. I made 3 dead centers using that datum, and they all fit perfectly.

Anyway, I see that I have plenty of data now so I will start cutting & see what the taper attachment is set to (I measured it last night at .0255”/inch).


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## erikmannie (Feb 4, 2021)

I am turning between centers & I will allow the dog driving pin to get this close to my tool shank.






Also, the 4” lathe dog will get this close to the gap bed.


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## erikmannie (Feb 4, 2021)

I am only able to take .020” lubricated cuts at 250 RPM, .005”/rev feed on this 4140 prehard.

I am also getting chatter on the tailstock side.

I am going to switch to HSS. When I tried to go up to 380 RPM (using A6 carbide here), the chips were dark purple (so too hot).


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## erikmannie (Feb 4, 2021)

I saw that the tailstock quill was sticking out way longer than necessary. I fixed that, and the chatter seems to have gone away.

Now I have switched to HSS. I lowered the RPM to 180, and my DOC is .010”. The whole setup seems much better behaved.


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## erikmannie (Feb 4, 2021)

It took me 2 hours to reduce the diameter by 0.415”. With the HSS, I ended up at 130 RPM with .030” radial cuts.

I just switched back to carbide & I will try cuts of .030” or greater. However, a cut of .025” with the carbide at RPM caused this awful chatter. I will increase the RPM to 180 now for .030” cuts.


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## ddickey (Feb 4, 2021)

A lathe that size you should be able to take .150" DOC easy on prehard.
How long is that piece? Finish looks horrible.
What the diameter? What's your feed rate?


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## erikmannie (Feb 4, 2021)

The piece was 10” before I faced each side about .050”.  The diameter started out 4”. My feed rate is .005”/rev.

At this point, I’m just trying to get the diameter down to 2.800”. I am really kicking myself for not starting out with 3 inch bar!

The finish was nice with the HSS. These carbide inserts obviously call for deeper cuts.

I realize that the finish is absolutely horrendous. I have to think that that is because of the .020” DOC for the carbide. 

Maybe my insert needs to be rotated:


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## davidpbest (Feb 4, 2021)

Your DOC should be at least 1/2 the nose radius of your insert or the surface finish will be crappy.  The TNMG tool and insert are also not ideal for this kind of machining which is probably why you can’t get the DOC up to 0.100”.  Compound position matters a lot too - if it’s hung out cantilevered, rigidity goes down the tubes on this lathe.


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## erikmannie (Feb 4, 2021)

This is very smoky, too. This is a .040” cut.


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## erikmannie (Feb 4, 2021)

Here is the resultant finish. Also, a picture of how my compound is set.


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## erikmannie (Feb 4, 2021)

davidpbest said:


> Your DOC should be at least 1/2 the nose radius of your insert or the surface finish will be crappy.  The TNMG tool and insert are also not ideal for this kind of machining which is probably why you can’t get the DOC up to 0.100”.  Compound position matters a lot too - if it’s hung out cantilevered, rigidity goes down the tubes on this lathe.



My inserts say TNMS. Do you have any idea what sort of insert I should use for roughing prehard 4140?

I don’t see the need to have my compound set at 30° at this point. I’m going to set it at 0°.

If the minimum cut is as large as you say, how does one use a carbide insert to zero in on the last few thou or tenths?


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## ddickey (Feb 4, 2021)

Do you have any left hand cutting tools?
Try taking a cut from the HS to the TS.
Also, Have you checked your gibs?


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## erikmannie (Feb 4, 2021)

ddickey said:


> Do you have any left hand cutting tools?
> Try taking a cut from the HS to the TS.
> Also, Have you checked your gibs?



Yes, I have numerous left hand cutting tools. I will try turning outward like you said.

The gibs are as they came from the factory about 3 months ago. I will check the gibs. Good point.


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## ddickey (Feb 4, 2021)

Ideally you would not want to be making small .001 cuts to hit a diameter. If you had to use a super sharp tool with a very small radius.


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## erikmannie (Feb 4, 2021)

ddickey said:


> Ideally you would not want to be making small .001 cuts to hit a diameter. If you had to use a super sharp tool with a very small radius.



I see that I’ve been doing it wrong.


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## ddickey (Feb 4, 2021)

I'm no expert just things I've learned in the last several years.
Ray C had a nice explanation on how to hit your numbers and the process of how it's done. I'll look for it and post it for you.
Sort of starts at post #36.








						Bull Nose Live Center
					

I'm told there are three kinds of lathe operators, those that use toolpost grinders, those that do it begrudgingly and those that simply won't allow it.  Right now, I'm somewhere between "begrudgingly and won't allow it".  That said, I'm pulling the tool grinder out of storage.  I've been...




					www.hobby-machinist.com


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## davidpbest (Feb 5, 2021)

I'm not sure if you're asking for help/suggestions, but if you are, here are some ideas.

Make your setup as rigid as possible. That would mean taking as much slop out of the cross slide and compound ways as possible.  If you haven't already, I would recommend removing the gibs on both control surfaces, hone them on a stone to remove any burrs, and check them for flatness.  Assuming they are flat and free of burrs, I would then fit them and adjust them using a dial indicator to remove as much sponginess as possible and still have the surfaces free moving.  Here is a link to another thread where one technique is documented to check the rigidity of the compound after adjusting the gibs.  _*Go here*_.  

Looking at some of your surface finishes, I suspect you have some rigidity issues, which is why I mention the first point about the gibs.  But you can improve rigidity by pulling in the compound so that the QCTP is sitting directly over the swivel-mount for the compound, and 90-degrees to the spindle axis.

Further along in that same thread, the problem he was having was lack of rigidity because the compound was not sitting flat on the cross slide. You can *see that here*. Rigidity is king, so check out your setup with some dial indicators - who knows, you may have the same warped compound base that TX Cowdoc did.

I am not a fan of the type triangular insert you are using.  It has a relatively weak cutting point.  I would favor an 80* rhombus style insert and tool holder - CPMT style.  But, if you want to use that triangle-shaped insert, I would pick one graded for use with tougher materials.  Assuming the I.C. of your insert is 3/8", something_* like this*_ would be a better choice. I would also tweak the lead angle of the tool by rotating the QCTP 10° or so CCW from where you show it in your videos, so that the radiused tip is doing most of the work and the cutting forces are toward the chuck rather than across the spindle axis. With decent rigidity, shifting the lead angle to balance the tool forces toward the chuck, and a proper grade insert you should be able to peel of 0.100" per pass no problem and get close to mirror finish.

ddickey suggested a good post by Ray C on how to hit target diameters without trying to creep up on final size with tiny skim cuts.  Creeping up is definitely asking to overshoot your target OD and leave questionable surface finish.  I use a balanced cut method, somewhat similar to what Ray C is trying to convey but without all the math.  It's fully described in much simpler terms_* in this video*_, and I use the DRO instead of the dials. Using this technique on my PM1340, I can routinely hit target dimensions to within 2/10ths, and there is no way this is possible creeping up on the final OD with shallow finishing passes. Granted, I have a solid tool post which helps, but even with the compound, this method works. Watch Stefan's video to the end, and realize that the technique is even more accurate using a DRO. He is also demonstrating the technique on 4140 with a similar sized lathe, using the style of insert (CPMT) that I would pick for your material and machining condition.

Hope this helps.


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## erikmannie (Feb 5, 2021)

davidpbest said:


> I'm not sure if you're asking for help/suggestions, but if you are, here are some ideas.
> 
> Make your setup as rigid as possible. That would mean taking as much slop out of the cross slide and compound ways as possible.  If you haven't already, I would recommend removing the gibs on both control surfaces, hone them on a stone to remove any burrs, and check them for flatness.  Assuming they are flat and free of burrs, I would then fit them and adjust them using a dial indicator to remove as much sponginess as possible and still have the surfaces free moving.  Here is a link to another thread where one technique is documented to check the rigidity of the compound after adjusting the gibs.  _*Go here*_.
> 
> ...



The main purpose of this thread & most of my forum activity is to provide & receive help with machining. Your quoted response is tremendously helpful. I can only hope to pay it forward someday.


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## erikmannie (Feb 5, 2021)

Well, I can’t think of a better example of forum people helping to solve a problem than what I saw today.

Here is how I ran it today: 
(1) set compound to 90°, 
(2) used a chuck, 
(3) adjusted my cross side backlash in such a way that there is now more resistance in turning the cross slide hand wheel (it was really loose before),
(4) fresh insert tip to start the day,
(5) checked that the tool was on center,
(6) set my toolpost for about a 10° angle of attack,
(7) no lubrication because of what was going on in my house (not a good time to make the house smell like sulfur),
(8) changed the feed to .017”/rev,
(9) set RPM to 250,
(10) DoCs between .030” to .045” (and keeping track of how much it actually cut!),
(11) minimal tailstock quill and tool shank stickout,
(12) locked the compound, and
(13) I was using the power feed and the taper attachment the whole time.

Here are some pictures of the set up:


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## erikmannie (Feb 5, 2021)

The final pass was .0277” (radial). The situation in the house changed, so I was able to turn on the CF. Here are 4 action photos:


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## erikmannie (Feb 5, 2021)

Here is the finish that I have to work with.


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## davidpbest (Feb 5, 2021)

Looking a lot better.  A different grade of insert can help further.  As a roughing operation that surface finish is fine.  Getting to higher surface finish will probably require an inset graded for finishing operations.  If you have the original package for your insert, and if it has any printed nomenclature on it, I‘d love to see a photo of it.  A finishing insert will have a smaller nose radius, and the feed rate will need to be lowered as well. This is the kind of information I’m talking about - all that gibberish includes the grade info as well as the feed/speed formula. The P05-P30 is the ISO grade specifying this insert is ideal for medium to fine finishing operations on steel.  This one would likely perform better in your application If it’s the right size for your tool holder (it’s ⅜” I.C.), and *available here* as a single insert for $9. 






Your chips look good considering the insert’s chipbreaker style, but I’m curious if most of the heat is ending up in the chip and not in the part being machined.  So if you have some idea how hot the part gets after a pass that would give some hint as to your feed/speeds settings.

I didn’t realize you had a taper attachment, but that too can contribute to lower rigidity - introducing additional backlash slop in the carriage if it isn’t dialed in properly. With the carriage locked, which is great, I believe you are essentially eliminating any of the taper attachment sloppiness from the equation.  Once you start using the taper attachment, it could be a source of additional issues.  Hard to know at this point, but something to watch out for.


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## erikmannie (Feb 5, 2021)

I used the compound to taper a 30° angle. I got tuckered out before I could put on a fresh tip for the final pass.

There is a witness mark at the base of the taper. The length between this witness mark and the chuck will be turned down so that it fits well inside the 2.55” spindle pass through.


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## erikmannie (Feb 5, 2021)

davidpbest said:


> Looking a lot better.  A different grade of insert can help further.  As a roughing operation that surface finish is fine.  Getting to higher surface finish will probably require an inset graded for finishing operations.  If you have the original package for your insert, and if it has any printed nomenclature on it, I‘d love to see a photo of it.  A finishing insert will have a smaller nose radius, and the feed rate will need to be lowered as well. This is the kind of information I’m talking about - all that gibberish includes the grade info as well as the feed/speed formula. The P05-P30 is the ISO grade specifying this insert is ideal for medium to fine finishing operations on steel.  This one would likely perform better in your application If it’s the right size for your tool holder (it’s ⅜” I.C.), and *available here* as a single insert for $9.
> 
> View attachment 354217
> 
> ...



Here ya go. I will also add a link here, as well. Not much information on the packaging, right?






I’m actually so broke for the next 8 weeks that I can’t afford $9! This machining hobby can be a little expensive.





__





						Carbide Insert TNMP-332-A6
					






					www.aloris.com
				









My LH, RH & chamfer shanks all use the same inserts in the green box pictured above, which I like. My tool shanks are these type:





__





						Aloris Double-Lock Tool Holder ADS6-3
					






					www.aloris.com


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## erikmannie (Feb 6, 2021)

So I used 8” and 10” smooth files and green Scotch Brite to get the surface finish to my liking.

The OD at the base of the taper was spot on at 2.634”.

The resulting taper is .090” over 3.5206”, so I ended up with .0256”/inch taper. The first time I did this, I aimed for .0256”/inch.

However, additional measurements made from the spindle nose and by remeasuring the factory reducing sleeve called for .0240”/inch and .0236”/inch respectively. Later today I will be able to find out how well this fits.


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## erikmannie (Feb 6, 2021)

Here is the parting operation.

I just had to make the base smaller than the spindle through-hole.

I will fine tune the 60° tip when it is in the spindle nose.


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## erikmannie (Feb 6, 2021)

Parting the 4140 prehard took longer than parting low or medium carbon steel. I broke one insert being overly aggressive.

I was so happy when it fit nicely.











Now the only problem I would have left is if it gets jammed in there while I’m cutting the 60° tip.


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## erikmannie (Feb 6, 2021)

This is the finish I get when I recut the taper while the dead center was in the spindle nose. I’m just going to leave it like that because I will have to recut the 60° every time I use it.


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## erikmannie (Feb 6, 2021)

Here it is sticking out of the chuck that is usually on the lathe. This is probably how I will usually use it. The jaws are 2-piece, so I can see myself taking off the top jaws.


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## erikmannie (Feb 6, 2021)

Here are all the dead centers from this thread. From left, factory reducing sleeve with MT4 center, 1018 steel first one I made, first 1045 steel center, second 1045 steel center, & 4140 prehard.

I would sell one, but only to a forum member. Text to (707)293-8973.


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