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Searcher7 Searcher7 is offline
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Default Import BXA toolpost experience

On May 31, 1:11*am, "DoN. Nichols" wrote:
On 2010-05-30, Searcher7 wrote:

On May 21, 6:51*pm, "DoN. Nichols" wrote:
On 2010-05-21, Searcher7 wrote:


* * * * [ ... ]

* * * * This is why I ask about the locking angle for one of the
supplied holders tried in both stations. *Normally, you should have the
same fit in both stations.


Yes. the supplied holders fit the same in both. In others words the
travel of the locking bar is about the same, regardless of which of
the two sides I use.(About 90 degrees, regardless of the supplied
holder I use).


* * * * From the most CCW starting position in both cases?


???

And when on the side it does fit on the swing distance of the locking
bar between locked and unlocked is only about 10 to 15 degrees.(Though
I don't know how important that is).


* * * * Given the starting angle, I consider it quite important, as the
lever will be over the tailstock -- and perhaps hitting a drill chuck or
live center mounted in it.


Ok. Since I don't have it mounted I can't be sure what will be in the
way.


* * * * *I* can -- from the photos alone.

* * * * Ideally, the unlocked position should be something like 3:00
o'clock (parallel to the bed, pointing towards the tailstock end of the
bed), and the locked position should be with the lever pointing out at
the operator.


Ok. With the tool post mounted 45 degrees from square(diagonal),


* * * * No! -- No! -- No! -- No! -- No! -- No! -- No!

* * * * The sides should be parallel to the chuck face and the bed,
*never* at an angle. *You can't do parting with it at an angle, even if
you can sort of make other things work.


I was just going by how it would have to be positioned in order for
the locking bar to, as you said, point toward the tailstock in the
unlocked position and toward the operator in the locked position.
(Don't worry. That is not the way it would really be mounted). :-)

The first two pics show the toolholder in it's proper relative
position opened and closed. Open would be more like 1:30 and closed at
7:30. (At about 5:00 I can still slide the supplied holders on).
http://s290.photobucket.com/albums/l...slander/Tools/

In the correct position
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *that
is the way it would be with one of the supplied tool holders on it.
Without a holder the locking bar will point toward the headstock.


* * * * Which means that it is likely to be hit by a swinging chuck jaw
and the knob be shattered. *(*Always* wear safety glasses when using the
lathe or mill.)

* * * * [ ... ]



* * * * If you have two lengths of round rod of the same diameter (e.g.
drill rod), set the lever in the fully locked position and try measuring
the width of the two dovetails. *Do this using the rods as follows
(view with a fixed pitch font like Courier to avoid distortion):


* * * *______________
* *( ) \ * * * * * */ ( )
________\ * * * * */_______


(the rods should be bigger, but that is the biggest that I can show
using ASCII graphics.


* * * * Anyway -- place the rods into the Vs of the dovetails, and
measure the width across the outside of the rods (using a caliper or a
larger micrometer).


* * * * The measurement across the rods should be close to the same on
the two dovetails. *If it is not so, then one of them is improperly set
on the threads.


I'm not sure what "close" would be but I just measured both sides with
a ruler.


* * * * I'm talking about measurements with something which reads out in
0.001" increments or better.

* * * * *And the measurements are 1-21/32" on the right side, and
1-2/3" on the left.


* * * * What kind of ruler do you have which reads in thirds of an inch?
And if that is correct, they are just a bit out. *1.6563" vs 1.6667"
(giving fractional sizes with different denomenators leads to confusion.
Convert to decimal fractions *first*.

Ok. The ruler was actually normal one that shows 16ths.(Though it is
still easy to judge 1/32).

Anyway, it should have been written as 1-21/32 on the left and 1-20/32
on the right. Nevertheless I don't yet have any drill rod. Just drills
and taps.(And I still have to clean off the cosmolene).

* * * * And measuring with a ruler, without the rods is no way to
measure it, because the edge of the wedges has been "broken" to avoid
sharp edges, and there is no certainty that the same amount has been
ground off of each.

* * * * * * * * * * And I just noticed that the left wedge has some
play when the tool post is in the locked position. But in the un-
locked position it is the right wedge that has a slight amount of
play.


* * * * This is with no holder in place, I presume?


Correct.

And which are you
calling left and which right? *


From the perspective of viewing the tool post from the corner as show
in the third pic.

One should be the front (the side towards
a long workpiece) and one should be the side (on the left, towards the
chuck).


Yes. When on the compound rest..

* * * * Now -- just for the fun of it, do the same kind of measurement
*inside* the dovetails on both the supplied holders and the genuine
Aloris. *I suspect that you will find a somewhat wider measurement on
the supplied holders based on your fit experiments.


No doubt. I measured using the ruler and got 1-13/32" for the Aloris
and 1-14/32 for the supplied holders.


* * * * Again -- without the rods, you are measuring were the edges of
the dovetail were rounded off, not where the actual clamping forces
occur.

* * * * None of the photos show your post from the needed angle. *Look
at the toolpost diagonally from the corner between the two dovetails, so
you can see both wedges at the same time -- ideally with the viewpoint
at a level about half-way up the toolpost.


I took a another couple of pics, but it is difficult,because my Canon
G2 Powershot porduces washed out pics when flash is used or is too dim
when I don't use flash. The only good shot are outside when it's a
sunny day.
http://s290.photobucket.com/albums/l...slander/Tools/


* * * * O.K. *A trick is to put a white card in front of the flash to
bounce it up to the ceiling -- or if the flash is in the wrong place of
this -- bounce it to a side.


That is what I did. With the two newest pics I just covered the flash
with a double sheet of paper.(That worked out pretty well).

* * * * If you can easily see that one wedge is higher than the other,
you have one started on the wrong thread -- an assembly problem at the
factory. *You *can* go back to the vendor and see if he can supply you
with a replacement one.


I don't know about it *easily* being seen, but the right wedge is
*slightly* higher.


* * * * *I* can see it easily in the photo. *And that position may be
forced by the screw.

* * * * Take it apart as I described before and see whether you can
re-align the wedges. *And see whether the screw can be removed while you
are about it.


I'll be doing that today.

* * * * But what *I* personally would do is to disassemble the toolpost
to the point of removing the wedges (I described how to do this in an
earlier article today) and re-installing them so you get both starting
at the same time, and so the lever angle winds up more reasonable.


* * * * Note that if you do this, you will probably void the warranty,
so if this is important to you, try the vendor route first.


I got this tool post years ago, so that is not an option. :-)


* * * * O.K. *So fixing it is the only reasonable choice.

* * * * I seem to have already deleted the model number from the
toolpost, but do I remember it starting with something like "250-"? *If
so, that is not an AXA size. *The AXA should start with "100-" based on
the Phase-II system of marking. *Are the holders starting with "200-" as
well? *If so, you have a BXA toolpost, and it will never properly fit
the Aloris AXA holders. *And -- it will be too large for your lathe, as
well.


This guy on eBay is auctioning the exact set I have. 260608805552

(But he says 9 to 12" swing). ???

Here's an Aloris AXA that only says 12". 230481378998

And I assume this is the import knock-off of that also. 360260794079
(Which is what I have).

This is starting to become confusing. I e-mailed the original eBayer
to ask what the number is on the box for the AXA toolpost set.(Mine
has 250-100).

Here is one more. 310216774478

The dimensions of the square body of the toolpost are 2-23/32" tall,
and measured across the top is 2-15/32" by 2-2/32"(which is also the
diameter of the circular cap).

* * * * And if it turns out that the screw is not present in others, it
might be that the screw caused the wedges to be put in with this offset.