On May 17, 9:34*pm, "DoN. Nichols" wrote:
On 2010-05-17, Searcher7 wrote:
On May 17, 12:04*am, "DoN. Nichols" wrote:
On 2010-05-16, Searcher7 wrote:
* * * * [ ... ]
Yup. I do have the basic tool holders, but they are the cheap ones.
http://www.shars.com/products/view/1...ol_Post_Set_We....
* * * * O.K. *Without an AXA holder I can't verify whether the dovetail
fits the AXA or not. *You do have at least one genuine AXA (14N was
it?), so you can tell quickly.
AXA 12N.http://s290.photobucket.com/albums/l...slander/Tools/
* * * * O.K.
I have it in front of me as I type this. It slid down on the toolpost
about a half inch without use of tools, so I guess it fits.
* * * * Assuming that the locking lever is in the released position,
it should slide all the way on with no difficulty and certainly no need
of tools. *If it only goes on a half inch, then it is likely to not be a
proper fit -- unless your lever is closer to the locked position.
I think I'll e-mail Shars about this. I added a couple of pics with
the tool holder as far down on the post as I can get it. (Without
using a hammer). :-)
It's probably nothing, but If you look at the second pic there is a
screw that isn't *complete* screwed in flush against the bottom.
* * * * At least it is a wedge style toolpost, so it should deliver a
bit more rigidity.
* * * * But the main trick is to crank the compound back so the cutting
force is pretty much over the point around which the compound pivots.
The more you crank it out past that point, the more rigidity you throw
away.
I'm assuming that the diameter of the work piece will determine
placement.
* * * * Actually -- that is handled by the cross-slide leadscrew. *The
compound is usually only needed for feeding at an angle, and the most
common use (other than chamfering) is to feed in for multiple pass
threading, with the compound set at 29-1/2 degrees (for a standard 60
degree thread) to lightly skim the right-hand side as it does most of
the serious cutting on the left-hand side.
* * * * [ ... ]
My meaning was that I wanted to move *away* from the single operation
holder. (And that AXA22 looks really tempting). :-)
* * * * It might be nice for getting uncommon edge angles (in 15 degree
increments IIRC, not *all* possible angles), but if I had one, I would
set it up for one specific useful angle and leave it that way. *Whenever
you change the angle of the cartridge, you lose the benefit of the
indexable inserts and quick-change toolpost, and are back to having to
re-measure and set up for proper position.
But what if you need a consistent chamfer angle between multiple work
pieces? Wouldn't something like the AXA #22 be better than the
conventional H.S.S. bit? The idea is like you said to set it up at the
proper angle and leave it.
* * * * Unless you need a specific angle (say it is called out in the
drawings for the part) what you can do is to simply have a tool which
uses the same inserts you have for the 16N (or 12N) mounted on shanks
which have it point first, so it provides an angle of 30 degrees on
either side. *If you have two of these, mount one in a #1 holder in the
turning position, and another in the facing position, and you can do
either 30 degree or 60 degree chamfering by you choice. *(Your cheap
equivalents for the 16 would also do for that if you wanted a single
holder, but they would not use the same inserts which you already have.
* * * * There are a lot of things which you will eventually want to do
which require other holders and inserts. *You'll need boring bars and
holders for them. *You'll need threading holders and inserts, or plain
holders and appropriately ground HSS bits. *I think that with the lack
of rigidity of your machine, you will not be able to use insets for
threading SS -- and you don't mention *which* SS alloy. *Some are pretty
easy to work (e.g. 416). *Others will fight you all the way home (e.g.
304), but I think that any of them will require too much rigidity to use
carbide inserts with your lathe.
As for stainless. 316 and 416. (I do have some Aquamet lying
around,but know nothing about it's machinability).
* * * * Hmm ... 316 IIRC is one of the fairly nasty ones, but it is very
nice for rust resistance -- if you properly passivate it after turning
it. *Anywhere that it touches steel (e.g. the chuck jaws) will be a
place where rust will start. *And I don't think that you can handle the
passivating chemicals in an apartment building.
Yeah. That is way out of my territory.
* * * * Certainly in a New York apartment building. :-)
* * * * And -- with 316, you are probably in one of the the serious
work-hardening alloys. *If you don't have the rigidity and power to keep
it cutting, as soon as the tool starts to skate on the surface, it will
harden the material so it will be *very* difficult to re-start the cut..
That is why I'd need to get the correct diameters to begin with. It's
the threading of the S.S. that might be difficult.
* * * * And that will be difficult enough with 316 SS.
* * * * I tend to use an extended holder with my insert tooling for
threading.
There are so many tool holders that it can be overwhelming. I'd hate
to get one only to find that there was a better option.So I'm looking
at the "Universal tool holders" to see what is possible.
http://www.aloris.com/catalog/aloris_p10-11.pdf
* * * * Those are nice when you need an edge at a particular angle and
don't want to have to shift the toolpost from its proper
square-to-the-axis position. *But for general use, you would spend so
much time adjusting the angle for different things that would be better
spent dropping another holder in place for the task.
But I figured it would be more difficult to get precise angles when
using the normal H.S.S. holder/bits.
* * * * How are you going to get a precise angle which does not fall on
the standard multiples of the detents of the cartridge? *Re-checking the
PDF file which you pointed to, it moves in 15 degree increments.
I'm not looking for angles in between what can be gotten with this
tool. My meaning involved getting the *exact* same angle between work
pieces.
* * * * In which case, you don't need to have an angle which can be
changed -- just the extra straight-ahead shanks (for the same inserts)
and a plain #1 holder.
* * * * If you want to *cut* a specific angle, you set the compound to
that angle and feed in along that angle. *These could be some help in
that (fitting where you need to go), as long as you don't need an angle
below 60 degrees (the angle of a triangular insert). *For narrower
angles, you'll probably need one of the diamond shaped inserts. *One
common size has a 55 degree angle (not much better than the 60 degree
triangular). *Another is a much sharper angle, but I would have to look
it up to see what it was.
I might need to do some chamfering, so chamfering angle consistency
from one piece to the next will be important.
* * * * As long as you can accept either 30 degree or 60 degree -- use
what I suggested above. *If you want 45 degree, then the adjustable
angle insert may be the way to go.
45 degrees is exactly what I was thinking. :-)
* * * * Having lots of HSS bits on hand, and a bench grinder will allow
you to make tools to fit what you want to do. *Bear in mind that your
lathe will not have enough rigidity or power to handle form tools under
most conditions.
So I guess that turning the end of that S.S. rod *with a ball turner
is out. :-)
* * * * It depends on what you mean by a "ball turner". :-)
* * * * If you mean a tool ground to a specific female radius, it will
be a killer.
* * * * However, if you mean the kind with a tool pivoted on an axis
corresponding to the center of the workpiece, and with a single-point
cutter, you can do it with that.
* * * * The trick is to not take of material from too wide an area at
one time. *A narrow point is what you need.
So I guess that is more in the grinding than the angle.
Speaking of a bench grinder. I have a Ryobi 6" Thin Line Bench Grinder.
(BGH615 120V AC, 60Hz, 2.1A 3600RPM/TR/MN, 1/2" Arbor), and have been
doing some research on aluminum oxide wheels to get for it. *And think
I found a good supplier:http://www.abtec4abrasives.com/
* * * * In the UK? *Shipping may be a killer. *And are you seeing the
price in UK Pounds and mentally treating it as US dollars? *Look up the
exchange ratio -- and take into account the shipping costs across the
Atlantic.
Actually I was thinking in terms of the buying experience of another
who raved about their service and the wheels performance when he got
them.
* * * * [ ... ]
O.D. threading those 3/8" to 1/2" dia S.S. rods are just a single
"extreme" job for this lathe.
* * * * They will be "extreme" all right -- especially the 316..
I probably won't be trying to thread 316, which is only a possible
material. Metal(and sweaty hands) will probably come into contact with
it, so I'll probably use a different type if I can find something in
S.S.
* * * * 416 is not ast stainless, but is easier to machine.
So can I assume this is what you'd use if you were making a one piece
ball-top joystick out of stainless steel?
* * * * 316 was the material used to make the Nikor developing tanks
back in the 1960s and 1970s.
* * * * They were spun from sheet stainless, and resistant to attack
from any of the photo chemicals.
* * * * How long a thread do you need to make? *If it is any longer than
about four times the diameter (e.g. 1.5" for 3/8" diameter) you will
need to support the other end with a live center (which may get in the
way of the threading), and if it is more than about double that, you
will also need a traveling steady rest to keep it from bowing away from
the tool in the middle of the length. *(Do you have a traveling steady
(also called a "follower") for your lathe?)
The threads will only be 1/4' to 1/2" in. Though some future projects
will involve much longer and coarser threads on mild steel rods.
* * * * O.K. *Learn to thread on 12L14 first, and you will then know
that you can do it and what it feels like, and only have to worry about
how much more difficult 316 SS is. :-)
Is 12L14 good for something like a lead screw?
Yes I do have a steady and a follower rest. Both of which I want to
modifying to ball bearings, so as not to mark up the work.
* * * * Hmm ... open to debate. *With ball bearings, chips tend to get
trapped between the hardened roller and workpiece surface, producing
interesting dents.
* * * * The standard non-rotating pushers tend to just push the chips
aside. *A good bronze is the preferred material for such pushers.
Thanks. I didn't know that. So I'll leave the rests as they are.
* * * * * * * * * * * * * * * I was only thinking of insert tooling as
a *possibility* for when/if I couldn't get the H.S.S. bit angle right
for consistent threads. It basically comes down to what would be
easier and more efficient.
* * * * The angle will be right for the insert threading tools, but
unless your rigidity is greater than I expect, you may wind up breaking
lots of inserts. *(And there are no positive rake threading inserts, so
three corners is all that you get per insert. :-)
So I guess that even in mild steel threading would be difficult.
* * * * Depends on how deep a thread. *I think that you can do 12L14 to
20 TPI. *28 TPI or finer would be easier.
Thanks. Standard threads are all I can see myself doing in the near
future.
* * * * As for setting the angle, get a fishtail rule. :-)
???
* * * * Threading plastic should be fine. *Threading a free machining
mild steel (e.g. 12L14) should go fairly well if you don't have too
coarse a thread. *(Your main trouble with those small machines will be
getting the machine to go slow enough to let you disenage the threading
feed quickly enough as you approach the end of the thread.)
And I was about to start a thread on a spindle crank mod. :-)
* * * * O.K. *Not something which I have any experience with, because
the Clausing goes slow enough to be no problem.
(But I do have a bench block and taps).
* * * * Good for threading holes, but not rods.
Yes. I wouldn't try I.D. threading on my lathe or bother with O.D.
threading by hand. (O.D. is all I can see doing in the near future
anyway).
* * * * And if you are going to try to use a die on SS, you will need
some way to grip the rod without marring it. *316 SS, even with a good
choice of thread cutting lubricant, will generate serious forces.
Yes. I'm about to pick up some way and spindle lube via eBay, and will
be looking for a good cutting/tapping fluid.
220604490776
And though I'd never get it I thought this one was funny: 220606254543
* * * * However -- threading Stainless steel is going to be tricky with
your machine. *I've threaded 416 SS without problems. *But I'm not at
all sure what would happen if I tried 316 SS. *I don't have any, so it
does not matter at the moment.
I think that Aquamet might be a form of 316, but I don't know of it's
work properties. (It might have been a propeller shaft of something
similar). But smoothing it up will be all I need to do anyway.
* * * * Well ... you'll find out how it machines, anyway. :-)
* * * * What do you *need* to thread SS for anyway? *I thought that you
were mostly talking about making parts for video games.
Oh, that was the all stainless steel ball-top joystick shaft
project. :-)
* * * * O.K. *Turn a sort step the minor diameter of the thread to help
start the die straight and concentric. *If it is too long, plan to turn
it off when you have the threads properly done.
* * * * Good Luck,
* * * * * * * * DoN.
--
*Email: * * | Voice (all times): (703) 938-4564
* * * * (too) near Washington D.C. |http://www.d-and-d.com/dnichols/DoN.html
* * * * * *--- Black Holes are where God is dividing by zero ---
Thanks a lot. :-)
Darren Harris
Staten Island,New York.