Now I'm moving into the tooling phase. I'm told to avoid the cheap sets of insert tooling which offer five tools in one set(each at a slightly different angle),because the inserts tend to break easily, there is no carbide anvil to support the inserts, and the inserts are more expensive than common industrial ones.
I'm guessing that the reference was to sets like this:
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The designations for the inserts are still confusing because it seems like every manufacturer uses their own numbers. The only way to know which are quality tools, what the numbers mean, and the ease and cost of insert replacement is to ask those who have experience.
So can anyone give me recommendations?
Now. I would like to cover all bases with as much ridigity as possible.
A) Facing B) Turning C) Boring D) Threading(Outside) E) Threading(Inside) F) Cut-off(Parting)/Grooving
Any thoughts on these?(Or they also the "cheap" tools that I'm told to avoid?).
I don't agree with this. I have a set, 1/2" shank, and they work well. I bought a whole bunch of TT-321 inserts for about a buck apiece (had to buy like 500 to get that price) and they last a reasonably long time as long as I don't do something dumb. I was turning some 303 stainless the other day on my 9" South Bend (not the most rigid beast) and it came out like chrome using one of these inserted tools.
Anyway, if your lathe is 10" or smaller the tribal wisdom on this NG is to use HSS tooling and learn to grind it correctly. HSS toolbits are cheap, and if you practice a little, easy to grind to get a good cut. Invest in some hand stones if you do go with HSS; you will be stoning the edges a lot.
I've gotten unanimous recommendations for insert tooling, as far as what's easier *and* more cost effective in the long run.
It seems that grinding those angles perfect would be a PITA, and I've yet to find a good tutorial for this.
My lathe is a 7" X 14". I've never read anything about using HSS if one's lathe is under 10". Does that mean HSS as opposed to insert tooling? And if so, what would be the reason for this?
... Grant is right that the received wisdom in rec.crafts.metalworking is to use "scary sharp" HSS bits on small lathes. Some of the usual reasons are that carbide inserts ordinarily are not as sharp; may use more negative rake with consequently increased cutting force, so work better on more-rigid machines; and for good finish usually should be run at higher speed than small machines have power for. While it is true that insert tooling is easier to use [at least when starting out] the idea that it's "more cost effective in the long run" is questionable. Anyway, for your 7x14 lathe, I think you should have a set of 5/16"- or 3/8"-shank carbide insert tooling and should also learn to grind good angles on HSS tooling. For some materials, eg aluminum and some stainless, in my experience you get ok finishes with carbide inserts; but when turning mild steel to diameter, I often get rougher surface finish than I like, with carbide inserts on my 7x10.
Note, to see some of the other 202 threads about this issue, hit
O.K. That looks like AXA size (probably Phase-II series 100). And hopefully, you also have gotten the modified toolpost to put the top edge of the tools at the centerline, as without that, they will be too high for your machine.
For those holders in general, you will want 1/2" tool shanks (the largest which your holders will accept, just as 5/8" is the largest that my BXA series will accept.
These are exactly the ones which I meant.
First off -- have you found the charts of insert sizes in your MSC catalog? (It is good for more than just ordering tools. :-) There are charts of the numbering scheme from at least two makers of inserts.
O.K. For that, I would suggest the Aloris AXA-16 or AXA-16N toolholder. It handles both boring and turning with one holder (two inserts -- one at either end. It should be at page 1626 in the MSC Big Book. As far as I can tell -- none of the other companies yet make ones like this.
Here is what it (the 16N version) looks like:
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The 16N is for negative rake inserts, but there are inserts for it which have a chipbreaker groove so designed to make the actual rake positive. But, you still get six corners, as you can flip the insert upside down after the first three corners are used up. The ones which are positive rake only give you only three corners.
This has a built-in chipbreaker for each insert which is part of the clamp which holds it.
You set the height once -- and that is right for both the turning and the facing inserts.
You'll have to order the proper size inserts for it. I could tell you the proper ones for the BXA-16N, but the AXA-16N takes a smaller size. (Ask MSC when you call them.)
Lots of choices -- and they tend to be weaker than the turning and facing tooling. And there does not seem to be room for carbide anvils with those.
Those that you found below (the 7586286270, IIRC) will probably do. Just make sure that you can get more inserts for them.
For those, you will need different tooling and different inserts. Look in the MSC catalog under the names Valenite and Iscar. Find the shanks first, in the proper 1/2" shank size. Then from there, find the inserts for the threading which you want to do.
Look on page 667 for both external and internal holders (not the miniature ones, I think), and the threading inserts.
Beware that you cannot use the same inserts for internal and external threading. The "spur" is on a different side of the corner for each.
You've got a good holder with the toolpost set. I personally would go for the T-profile Cleveland Mo-Max parting tools. They are the "P" type blades. Go to page 550, and select the height to fit your holder. (I use the BXA, so the size for mine will be different.) Given the probable power of your spindle motor, I would suggest going for the narrowest of these blades which you can find to fit.
This looks like a potentially useful set. And the wrenches (and screws) are the special Torx ones, instead of the Allen keys which round out rather quickly on the cheap sets.
And this one is particularly interesting. Note that the included angle for the threading tool (LW) is 55 degrees. This is right for cutting Whitworth threads, but you are highly unlikely to be cutting those. 60 degrees is far more likely.
The two of the remaining tools appear to use the tiny 55 degree insert which the tools for my Compact-5/CNC uses. They are very nice, and the inserts which I have are very sharp (no TiN coating), but hard to find. I lucked into a large bag of them from another regular on this newsgroup several years ago.
I use one of these on the Big Clausing, when I need a nicer finish, instead of quicker cutting and greater rigidity.
Unfortunately, there are two other insert styles not counting the grooving/parting tool.
These are too small to offer the carbide anvils, but seem to hold up a lot better than the cheap sets -- even in the same machine.
The 3 or 4 eBay sellers of this tool post either couldn't give me info on it or basically said that a slight modification is needed to attach it to the lathe it will be used on.
Yes. And the #4 will take up to a 3/4" boring bar.
----------------------------------------------------------------------------- ***Page 603: Basics of... Indexable Toolholder Nomenclature Page 613: Toolholder/Boring Bar Parts and Components *Page 625: (MFG Advice) Seco/Carboloy(Cut-off & Deep Grooving System) Page 650: (Valenite) Threading & Grooving Tool Holders Nomenclature Page 651: (Valenite) Grooving Inserts Nomenclature Page 652: (Valenite) Threading Inserts Problems and Solutions Page 653: (Valenite) Thread Inserts/Boring Bar Nomenclature ***Page 661: Basics of... Carbide Threading System Nomenclature Page 669: Threading System Nomenclature Page 670: (Seco/Carboloy) S-Type Threading Inserty System ***Page 740: Basics Of... Boring Bars Page 748: (Circle) Precision Boring Tools - Technical Information
I was actually looking at one on eBay(7603410647). But I didn't bid because it wasn't the "N" version. However, looking at the price of these in the MSC catalog makes me wonder if I really need such a tool holder for such a relatively weak lathe. Are you really saying that the
16N inserts(that allow 6 usuable corners) are in the long run more cost effective than other tool holder/insert options?(Especially since the inserts are probably expensive also).
I wouldn't know how to go about that. I couldn't find them in the MSC catalog. And the seller doesn't answer the phone or return e-mails(unless it's an e-mail invoice).
Perhaps I should drop the idea of internal threading on a lathe. I would love to be able to make some deep thread in small diameter holes and will concentrate on the hand taps for this. I did pass up on these:
7603091649-7603091640-7603091620 and I'm wondering if I erred.(I know you don't like purchasing loose tooling).
The external one(SER 0500 F16) at almost $100 makes me think that I should probably practice with a cheap eBay holder first. :-)
I guess that would be the 0.040" thick, 1/2" high, 3-1/2" long blade.(I'd just have to decide between HSS and Cobalt).
Here's another set from the same seller: 3868312551. But it seems too limited,(and it doesn't use the hex scres you mentioned). Realistically, I'd like to be able to srill/bore/ream/thread a 1/4" diameter hole deep enough to allow a screw rod a 2-1/2" to 3-1/2" travel, for one of my projects. :-)
This is the seller I've gooten most of the lathe realted items from. But his ads seems to have at least one or more issues: Not enough info on these: 3850535882 No hex screws that you mentioned: 3875494246 One of the cheap sets to avoid: 7557708701
By the way I did wins some Boring head shanks: 7603073759.(Just for the MT2 one of course). :-)
Yes. I noticed that. I'll be staying witht he commen standards for the most part. External thread tooling that will correspons to the tap & drill set I mentioned I ordered. So I'll forgo that tooling set.
Easy to get(and hopefully relatively cheap) inserts are also a priority for the holders I get.
I like to think that my lathe's lack of power will ensure that I won't run into some of your problems. :-)
The "slight modification" is the reshaping of the steel plate which becomes the T-slot nut for most normal lathes.
For *your* lathe, as shown by the URLs which you have posted from the importer, you *need* a modified compound -- on which has been milled so it is not as tall. Otherwise, you will not be able to get your tools adjusted low enough to reach the spindle's center line.
You *must* either get this modified compound to use the AXA size toolpost, or get a stand-alone milling machine to make the modifications on your own.
The part which gets the "slight modification" for normal lathes is simply tossed aside, and the center rod screws directly into your compound.
Until you get that modified compound, you *can't* use your new toolpost.
O.K.
[ ... ]
I have made what recommendations I am willing to spend the time on. I type with the keyboard on my lap, and typing with the MSC catalog in my lap (there is no other place to put it) is just too awkward. I did web searches for what I posted before.
[ ... ]
The price was dirt cheap. It would have been worth while to use with the normal inserts, and save the purchase of the 16N version until when one comes up.
The inserts are less expensive than the ones for the junk sets, especially when MSC puts them on sale. Plus, you can sometimes luck into 100-quantity lots (with perhaps the wrong holder) on eBay. I got some with 3/4" shank holders, which I had to mill down to 5/8" to fit the BXA toolpost tool holders which I use.
And the particular advantage of the 16N (or the 16) is that you need only one holder for most of your work (other than threading), and that frees two holders for things like threading tooling. I have about ten normal holders, plus the BXA-16N.
In which case, you may need to skip them.
Hmm ... small holes don't go well with single-point threading, so you don't need the insert tooling for that. I generally use mine for internal threading of holes 1" and larger.
I find myself wondering why you even *considered* these. They are what are know as "pulley taps", designed for threading holes for setscrews in the hubs of pulleys, where a normal tap can't reach because of the diameter of the tap wrench.
Note that each of these (which are probably pretty good, in that they still have the protective wax over the cutting parts) have a section where the shank is the diameter of the full size of the thread before going to the extended reduced shank. This means that you *cannot* tap a hole any deeper than you could with a normal tap. You can simply reach a hole which is otherwise awkward to reach, but you can tap no deeper.
Why do you need deep tapped holes, anyway? Normally, you don't really need any more than the diameter of the thread worth of thread length for full strength. Any more simply adds to the wear of the taps.
If you are after small diameter threads, you want taps and possibly dies in a sliding die holder. And single point threading is not going to work for deep holes anyway -- even with larger holes.
The external one is probably better for your use than an internal one. I do have one special internal one small enough to (barely) manage internal threading of 1/4-20 or perhaps 1/4-28. And I would do that only on the little CNC lathe, because you can't see enough with internal threading that small to do it manually -- except perhaps with a steep learning curve (e.g. many broken inserts.)
[ ... ]
Cobalt. It costs more, but it is tougher. It is what I use for most parting.
It uses the Torx screws which I mentioned, The hex ones are the ones to be avoided. You can usually tell (even if the photo is poor) by the wrench having a plastic flag molded over it, usually with a straight extension for spinning the screw down until you get to the point where you need to actually tighten it, at which point you shift your grip to the flag.
Forget single point threading with insert tools for your 1/4" thread.
Is there any reason why the hold can't be drilled clearance diameter for part of the way, and threaded only part?
Not for a lathe. Those are milling cutters -- and not even end mills, given the orientation of the inserts. You won't need them until you get a stand-alone milling machine.
Those *do* have the screws which you want.
However, they are for use in a boring head in a milling machine. And one large enough so I suspect that you'll never get the machine to fit it upstairs. Those have 3/4" diameter shanks. Too big to fit in the normal tool holders for your quick change toolpost. (Though perhaps in the boring bar holder.) Yes -- you said that that will accept 3/4" shanks.
Of course, there is no clue who made them, or where.
Yep - avoid.
Hmm ... without knowing what thread your boring head will need? And a boring head is not useful in the toolpost or in the tailstock. It needs to be rotating, which means that you will need it to fit the headstock spindle taper (which I *think* was MT-3, not MT-2).
[ ... ]
And here, you are locked into a single vendor, until you can find the proper designation, and find them in MSC or elsewhere. (Or can luck into a bag like I did -- but that was a couple of hundred dollars, IIRC.
[ ... ]
But the relative lack of rigidity can exacerbate the problems. It can cause the insert to dig in and lean into the workpiece, thus stressing the carbide insert to failure.
I will proably not answer for a while. I am reaching burnout answering your questions -- and seeing you buying things without the proper accessories -- such as the toolpost without the modified compound.
Yes. The compound modification will be my first project.
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Yes, I had to type with the keyboard on my lap and had to keep grabbing and putting the MSC catalog to the side also. :-) Anyway, I just posted those to show what I was studying. I've learned a lot and now will use the as a reference for inserts. Btw. There is an eBay seller(samscarbidetoolclub) in my area that seems to deal in a lot of tooling inserts.
Cest La Vie.
These threading holders look nice though(7589501316). And I might consider an Aloris tool holder with the cartridge that locks in 12 different positions. I'm not sure which is the correct number because presently two eBay sellers are referring to them as #20 and #30.(7597347922 & 7600122977).
"Considered" may be a strong word. I saw them but didn't have time to find out what they were before the auction ended. The seller's list of auctions are basically non-tool related and I did want to take chances on his statement of them being NOS anyway because the auction pics were so bad.
The reason is because a couple of my projects will involve using threded rods to positively move components over a 2-1/2" to 3-1/2" travel.
For the projects I mentioned, I was thinking that I might have to thread both ends separately. But the screw rod would always have to be in contact witht he threaded portions at both ends, regardless of where it is in the travel.(I'll look up "sliding die holder").
Ok. So I guess that means that by the time I go through a single cobalt blade, I would have gone through more $ in HSS.(All factors taken into consideration).
Because the screw rod will be turned via gears and I'll need ridigity at both ends of the travel.
So I guess that set is still a possibilty.
As for the other two, I've decided against them because in the first set(7586286270) I'd only be able to use two of the bars. The 5/8" and
3/4". The second one(3868312551) has bars that wouldn't work for me because they are all 1/2" shank.(I didn't notice at first because of the inconsistent way the seller writes out the bar dimensions).
-snip-
My error. I meant to say MT3. The MT3 was the reason I bid on them in the first place. And for the price I got them for I figure it would be worth it.
That said, *after* I won them someone e-maile dme asking if I would sell the MT2 shank to him for $10 plus shipping, and I said yes.
*After* that I stumbled into this:
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the site indicates will fit my lathe.
Perhaps I can get that lucky, eventually. Thanks for the MSC reference. It has helped a lot and as a result I can do better eBay searches.
Actually that was a joke. :-) The idea is that I'm forced not to try the things you can do on your lathe.
I've learned a lot. That was the best option for getting the tool post without having to pay MSC prices. And the compound mod is well known with the mini-lathe owners who frequent mini-lathe.com and a couple of Yahoo Groups.
The modification is documented here:
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->
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->
QCToolPost.PDF
As I've said, you've helped me a lot already. And I just wanted to tie up the loose ends. I hope I covered everything satisfactorily.
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