My lathe has a round toolpost and a couple of lathe bit holders that
look like they are for 3/8 inch bits. Maybe I am really wrong, but it
seems like they are not big enough for this large lathe? Am I missing
something? Can I use 5/8" bits without the Armstrong tool holder?
The tool needs to be adjusted to have the cutting tip exactly at the
centerline of the work. Hard to do that with square tool bits and no
Bite the bullet and buy a quick change tool post. You will want the 200
or BXA series. Aloris is the top brand, Phase II works well. Wedge
holders are better, piston types are fine. Enco and others have regular
Part number 505-2172 at
No flames but perhaps some cold water.
The type of work done on the typical home/hobby lathe does not
require or justify the jumbo tool bits and inserts used in a
heavy machining production environment.
In a production environment, time is money, and a few minutes
saved on each part times 5 or 10 thousand parts quickly justifies
the more expensive tools/tooling.
In the home/hobby shop, it is very seldom that more than one or
two parts are run, thus a few minutes saved is meaningless unless
you are really turned by heavy blue chips and lots of smoke from
the cutting oil.
The typical hobby/home shop the lathe is either older but won't
turn fast enough to fully utilize the more expensive coated
carbide tooling, or it is newer and faster, but lighter weight
and not rigid enough to fully utilize the more expensive tooling.
Unless you are *WEARING* the tools out it is generally a waste of
money to go for the large premium / high-cost tools. In general
these tools, while harder and more heat/wear resistant, are also
more brittle and subject to chipping and cracking. They are also
frequently more susceptible to thermal stress which is a problem
with the typical paint brush or drizzle can coolant application
in the home shop.
Compare the prices for the 1/4, 3/8 1/2, etc. tools and you can
see a fairly steep increase in prices with very little if any
So unless you are turning full size train wheels or axles, try
smaller rather than larger inserts/bits. The smaller brazed
carbide tools are cheaper and the smaller HSS blanks are both
cheaper and easier to grind. Again unless you are actually
wearing the tools out rather than chipping, the premium HSS
blanks with 5% or 10% cobalt are simply *MUCH* harder to grind,
more expensive and are more brittle. The super premium TanTumg
HSS tools are even harder to grind and even more brittle than the
Even for Acme threading, a 1/4 square toolbit should cover most
home shop requirements, although a 5/16 or 3/8 bit may be handy
on occasion. The larger square tool bits do however make fine
parallels, and you should have several pairs for set-ups.
If by "round post" you mean the traditional American style
lantern tool holder, while these are slower to change out tools,
these have turned out enormous amounts of high precession work
over the years.
I would consider 1/4 square tool holders to fit the lantern style
holder. These come in two types, one called "carbide" with no
built-in back rake but usable with HSS tools and necessary for
threading to get the proper profile even with HSS tooling, and
the HSS type with built-in back rake [typically 15 degrees] that
simplifies tool bit grinding because you don't need to grind in
back rake. I have found the HSS holders to be quite acceptable
for use with brazed carbide tools for most home/hobby shop use.
For insert carbide tooling the front clearance my be a problem
and you may have to use a 0 back rake holder.
Most mill supply stores will have the lathe tool holders but as
an example click on
The key to using these holders is to get the tool set exactly on
center and an easy way to do this is to keep a new sharp dead
center just for tool setting. Put the dead center in the tail
stock and set the lathe tool to just touch the tip of the center.
There are also plans [or at least pictures] on the web for tool
[about 1/2 way
FWIW -- if you decide to use 1/4 HSS blanks as standard, buy 30
or 40 as it looks like the prices are shooting up like everything
else and these are cheaper by the 10 pack. [watch for sales]
price comparison between sizes see
Good luck and let the group know how you make out.
Unka' George [George McDuffee]
He that will not apply new remedies,
must expect new evils:
for Time is the greatest innovator: and
if Time, of course, alter things to the worse,
and wisdom and counsel shall not alter them to the better,
what shall be the end?
Francis Bacon (1561-1626), English philosopher, essayist, statesman.
Essays, "Of Innovations" (1597-1625).
adding my 2 cents - the genuine ALORIS stuff is quite a bit better than the
Chinese copies - get a real ALORIS tool post (used if you want to save $)
and a couple of BXA-1 and BXA 2 holders. you can get some cheap chinese
ones too, but they don't work nearly as well ** Posted from
If you have the cash to buy a BX knock off then by all means you should also
get some replacable carbide type holders and inserts... Quality, (not top
of the line but made in America) Holders are under $50 each from Enco, and
the import inserts are under 2 bucks each.
I'd suggest some C2 (for brass,cast iron) and C5 (for steel) TNMG inserts
and 3 holders, an MTENN (thats a "straight" one), and a MTANR and MTANL,
those are "sight" and "left" handed.
For under $200 you can have a pretty classy setup :-)
Here's a few Enco part numbers.
these 2 are import and I forget the tip radius.. you can look them up
344-3212 TNMG C2
344-3215 TNMG C5
these are 5/8 shank holders and should fit the BX just dandy fine.
422-2954 MTENN 10-3B
422-2958 MTANR 10-3B
422-2961 MTANL 10-3B
They way cool thing about these is when you break/dull a insert, when you
replace it the machine stays in calibration..
As Iggy said... Flame Away.. :-)
William, being a little pompous aren't we? I have been using the
"cheap chinese" on 3 of our bigger lathes here for about 9 years. They
still hold less than 0.001" when changing inserts. I can't see how an
Aloris could be any more accurate than that.
They are repeatable to within 0.001" when changing tools in the
holder. One lathe here does 3 different diameters on a production
shaft and the cross slide dial has not moved off a single setting. It
must have made 20,000 small shafts in it's time. Sounds accurate
enough to me.
If you or anyone else wants to waste money then have at it, but don't
knock stuff just because it is not stupidly expensive.
Enco has 1/2 shank tool holders too that take the T*** inserts. The AX takes
1/2 doesn't it?
FYI those holders I spec'ed for Iggy ( and I recently bought for the 5914
and *MY* BX knock off) were manufactured by Dorian and are VERY nice... The
lists them for $52 and Enco sold them for
$44.... hey that's almost 20% off :-))
STAY AWAY from any of the holders that take the TT inserts ( Enco and others
sell sets for SUPER cheap), they are made in India and are pure junk..
Hit the Enco site
and run the numbers I gave Iggy, all
the holders are on the same page.
Learning to grind tool bits from HSS blanks is a good thing too,
because there will be things which you can't find insert tooling for --
or can't afford for only one or two uses.
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Yes -- 5/8" shanks are the max size for standard BXA/Series-200
And -- you don't have to purchase a new insert right away. Each
insert Of those suggested (negative rake with a chipbreaker groove which
makes the effective rake positive) you have three corners, each
providing a cutting tip, and you can flip it over and get another three
cutting tips if your original ones have just gone dull. If you've
crashed and broken them, you will have damaged the other side too, so
you can't use the flip side tip.
And -- for much of your turning, a single holder, the Aloris
BXA-16N will hold two inserts at the same height. One is used for
normal turning along the length of a workpiece. The other is used (with
the holder mounted on the other dovetail) for facing work. And, they
will use the same inserts already suggested. This will take the place
of two of the three insert shanks suggested, leaving just the straight
ahead one (which produces a nice angle for chamfering/deburring the
edges of a workpiece.
So far, I have not found a clone of one of the BXA-16N holders
made by anyone else, and have not found the holders on eBay at a
reasonable cost (when the eBay price for a used holder is past 80% of
the *new* price, I choose to pay the new price, which is what I did with
the BXA-16N which I have.
Eventually, you will want other holders and shanks -- such as
ones for threading insert tooling. And the holder which I find nicest
for the threading insert tooling is the one which provides an extension,
so the shank is well supported while you have enough extension so you
have a better chance to thread something supported by a live center
without hitting the center's bearing housing with the toolpost's other
Gotta agree with DoN on the threading tool holder too, I just didn't want to
brag/confuse the issue.
I have the "mini-thin" one (Enco part number 359-5020). It's extra long and
as DoN points out it makes it nice if you have to hang it out for what ever
reason. You can get threading tips and VERY thin groove/cut off tips, my
fav for cutting brass tube is the .019 cutter. The tips have 2 cutting
edges on either end.
Besides 3 "normal" tool holders I've also have the cutoff blade, the boring
bar, the knurling tool which will mount a regular tool holder too but is on
the "backside" that I usualy mount a facing tool on, and a genuine BXA-5 #2
morse taper holder which I have yet to find a use for.. LOL.. I'd buy a
16N but it's too much cash, and all these holders came with my BX when I
bought the Lathe.
And yes I learned how to hand grind both regular and threading tools from
cobalt and use a "rocker" (lantern) tool post and holders in high school,
these T*** just make life too easy.... :-)