Aligning Radial Saw?
bwasson
could find to no avail. I'm trying to set-up and align an older
Craftsman Radial Arm Saw (probably 70s to early 80s vintage), and am not
sure how to best make adjustments (it's close to square, but not close
enough...). Do I basically just fiddle with the table and backstop until
I get it square, or can I adjust the arm itself using the mounting bolts
or whatever?
Any help or pointers to online RAS resources would be helpful.
And, yes, I know Craftsman RAS's aren't the necessarily the greatest,
but I got it for a good price and it's in perfect condition.
Many thanks,
Brian Wasson
Abington, Pa.
Edriese
allignment, I have never been successful. My problem seems to be the mechanism
that removes "play" between the column and the arm. Perhaps the wedge is worn.
Hope you have some luck finding help.
By the way,as in all Sears radial arm saws, the motor is special, and housed in
a unique configuration to accomodate the various angle settings. The motor has
failed. Sears parts & service people tell me the replacement part(s) are no
longer offered. In reply to my inquire as to what advice they might have, they
responded, "Buy a new saw." As the saw is perfectly good in all other respects,
I am reluctant to give up. Any ideas? ecdr...@ieee.org
Tim Pham
There is a specific methodology you must follow in order to get it aligned
just right. You can check out/buy a book on RAS and follow the
instructions. There are typically three adjustments that are made on a
RAS. Trying to describe on newsgroup would be very difficult, but here's a
condensed version.
1. Align your saw blade to 90 degrees from your tabletop
2. Align your blade to 90 degrees to your backstop
3. Align your radial arm to 90 degrees to your backstop
Good luck
jack_el...@my-deja.com
costs $4 or $5 to download but it is fairly straight forward. But you
should align the arm to the fence not the other way around. Also you
have to make sure the table is flat relative to the arm. then the blade
has to be square to the table and fence. If you can get an owners
manual it should have the sequence of aligning the saw and would be
more specific to your saw, but if you can't get one then I would try
the Wood Mag. guide
Sent via Deja.com http://www.deja.com/
Before you buy.
Praising Jesus
make the table top parallel to the arm, you need to align the frame to the
arm. So first, I remove the top and turn the saw 90 degrees so I can use the
end of the arbor. I then assure that the arbor has an equal space when the
saw is fully extended and fully retracted on the right and left side (use
feeler gages between the arbor and the frame. Once the frame and are arm are
parallel, Install the table and make the same adjustment. This time, move
the table top instead of the saw arm (using the set screws in the frame).
This assures the frame will remain stable as well as aligned. Some folks
just align the top without assuring it is aligned to the frame and as the
frame settles, the saw moves out of alignment.
---Mike
<jack_el...@my-deja.com> wrote in message
news:8pblnv$nac$1...@nnrp1.deja.com...
dwil...@wcta.net
>,;I'm sure this has been covered before, but I've searched what archives I
>,;could find to no avail. I'm trying to set-up and align an older
>,;Craftsman Radial Arm Saw (probably 70s to early 80s vintage), and am not
>,;sure how to best make adjustments (it's close to square, but not close
>,;enough...). Do I basically just fiddle with the table and backstop until
>,;I get it square, or can I adjust the arm itself using the mounting bolts
>,;or whatever?
Try www.sears.com or www3.sears.com and look for your model number.
You may find the manual and or the alignment procedure.
>,;
>,;Any help or pointers to online RAS resources would be helpful.
>,;
>,;And, yes, I know Craftsman RAS's aren't the necessarily the greatest,
>,;but I got it for a good price and it's in perfect condition.
>,;
>,;Many thanks,
>,;Brian Wasson
>,;Abington, Pa.
Ed Bennett
Hi Brian,
I read through the other replies and saw that a number of points weren't
mentioned so I thought I'd add my comments. This is long and detailed. I
hope it's useful for you and many others.
Many of the alignments on a Radial Arm Saw (RAS) are dependent upon eachother.
That's why it's important to do them in a specific sequence. Your current
situation comes from trying to make one alignment without addressing the
alignments that come before it. Also, the accuracy of each alignment will
determine the accuracy of subsequent alignments. So, doing the process by
trial and error is nearly impossible. You won't discover your error until the
end of the sequence and then you won't know which step was off so you'll have
to start all over. This is why many people give up and say that the RAS is
hopelessly inaccurate. I've used a '80s vintage craftsman RAS to do some very
accurate work to within thousandths of an inch.
I sell a products for aligning radial arm saws (RS-Aligner/TS-Aigner).
However, the process that I'm going to describe below does not require you to
purchase these products. Because accuracy is so important, I do suggest that
you use a dial indicator to make many of these adjustments. You can get one
from almost any of the woodworking catalogs for $15-$20 and you'll find it
pretty handy for many other things around the shop. There are other ways to
accomplish the measurements but keep in mind that accuracy is paramount.
Here's the sequence:
1. Remove play in the carriage and the arm.
Before you get started aligning your saw you should try to remove excess play
in both the carriage bearings and the arm angle lock. Aligning your saw will
be much easier if you take time to remove excess play. On most saws the
carriage bearings are found underneath the arm cover. They are adjusted by
loosening locking nuts and turning an eccentric. Be careful not to
over-tighten the bearings. This will reduce the ease of motion of the
carriage and also promote accelerated wear on the bearings. Removing play in
the arm angle locking mechanism is generally done by adjusting two set screws
in the side of the arm.
2. Set the table support brackets.
Remove the table top to reveal the table mounting brackets. Another poster
described this process using the end of the arbor and feeler gages. I like to
attach a dial indicator to the carriage. I point the stylus of the dial
indicator downward so that I can take measurements from the surface of the
table support brackets. The idea is to adjust the bracket surfaces so that
they are parallel to the *travel* of the carriage and level to eachother.
3. Level the table top.
Even though the table brackets are aligned, the table top may not be perfectly
flat and so your cuts won't be accurate. Therefore, most manufacturers have
adjustments for leveling the table top as well. Typically, adjusting screws
are supplied to push up or pull down on the center of the table.
Note: As you move the dial indicator across the surface of the table, the
needle on the dial indicator will probably jump around quite a bit. It is
registering the smoothness of the table surface and also the smoothness of the
bearings in the carriage.
It's best to check the flatness of the table across as much of the surface as
possible. Realize however that you may not be able to make it completely
flat. A good compromise is to make sure that the table reads roughly the same
in the center as it does on the edges. It's not completely unreasonable for
the table to be out by as much as 0.010" - 0.020" across its entire surface.
If the table is much worse than this, you should consider replacing the table.
Don't give in to the temptation to adjust the table brackets to compensate for
a warped table surface. For more demanding applications you might consider
replacing a wooden table with one made from more stable solid surface
material.
4. Setting the zero point of the arm.
Most radial arm saws have a detent when the arm is supposed to be at 90
degrees to the fence. For general work, this detent comes in quite handy.
Most saws allow you to adjust the angle of the arm relative to the position of
the detent. A common mistake that many people make is to align the blade
before setting the zero point on the arm. Be careful to make sure that the
arm is aligned before you proceed to align the blade.
Many people use a framing square for this. I don't believe that a framing
square is accurate enough. I suggest using a dial indicator with a large
indicating square. Such a square is pretty pricey ($90 - $120) so you may
want to try a framing square first to see if it's good enough for your use.
Place the square on the table with the beam against the fence. With the dial
indicator attached to the carriage, place the stulus so that it rides on the
edge of the square. Adjust the arm on the saw so that it is locked in place
at the 90 degree detent. Move the carriage down the arm and observe the
reading. Changes in reading indicate how far out of square the arm is with
the *travel* of the carriage. If you don't want to use an indicator, you can
check to see if the tip on a blade just barely touches the square at both ends
of the travel. (It's a "feel the rub" technique that I dislike but some
people can make it work well.)
On most saws, there are setscrews in the column that ride against a square way
with gibs. These setscrews can be adjusted to change the angle of the arm
even though it's locked at the detent. These screws also affect the stiffness
of the blade elevation mechanism so they must be carefully adjusted. If they
are too tight the blade elevation mechanism will be difficult to operate and
there will be excessive wear. If they are too loose, then there will be play
allowing the arm to move side to side. So, you must adjust them with two
things in mind: angle of the arm and motion of the elevation mechanism.
When there is no change in reading on the dial indicator as the carriage is
moved down the arm, then the arm is square with the fence.
5a. Aligning the blade (vertical heel adjustment)
Before you begin this procedure, you must make sure that the arm is perfectly
square with the fence. If it isn't, your blade alignment won't be accurate.
The whole carriage assembly is usually designed to rotate for rip cuts.
Typically there's a detent at both the crosscut and rip positions and there's
an adjustment to make sure that the detent positions provide adequate blade
alignment. Make sure that the carriage is locked in the 90 degree detent for
crosscutting. Adjusting the carriage usually involves loosening the bolts
that connect the carriage and the yoke and moving the pivot points side to
side.
Start the alignment procedure by moving the carriage somewhere near the middle
of it's travel. Fixture the dial indicator so that it remains stationary on
the table surface and the stylus is against the blade. Now move the carriage
and observe the reading on the dial indicator. Ideally, a perfectly aligned
blade will show no change in reading along it's surface as the carriage is
moved. However, if the blade isn't flat then you'll be measuring blade warp.
You can avoid this by rotating the blade as you move the carriage so that you
take your second measurement at the same spot on it's surface. Use a pen to
mark the spot and avoid confusion. Adjust the carriage to eliminate any
change in reading from one end of the blade to the other. Don't adjust the
arm angle to compensate for blade misalignment. This is probably the biggest
mistake that people make with the RAS.
An alternative method that doesn't use a dial indicator involves placing a
square with it's beam against the fence. Hold up the other end so that the
blade of the square goes across the saws blade. You want to adjust the
carriage to remove any gap between the edge of the square and the surface of
the blade. The problem with this method is that it can be affected by the
blade not being square with the table. So, if you use this method, then do
step 6 first, then come back to step 5.
5b. Aligning the blade (horizontal heel adjustment).
The axis of rotation for the blade tilt mechanism must be parallel to the
table surface. If it isn't, then your blade will move out of alignment when
it is tilted. Do this by rotating the motor so that the arbor points
downward. Attach a dial indicator to the blade and point the stylus downward
so that it contacts the table. Then "sweep" the table by rotating the blade
and observing the reading on the dial indicator. It should be the same all
the way around (with allowance for table surface roughness). If it isn't,
then losen the bolts that connect the carriage to the yolk and move the pivot
points up and down. Obviously, you might disturb the vertical alignment
during this process so go back to 5a and re-check it.
You could do this without an indicator by attaching a pointed stick to the
blade and "feeling the rub" all the way around. Again, I dislike "feel the
rub" techniques but some people can make them work. Seems to me that $15 is
well spent on a dial indicator!
6. Squaring the blade with the table surface
Now you're ready to make sure the blade is square with the table. Again,
there's generally a detent for this 90 degree setting so make sure your yoke
locked in this position.
The adjustment is usually made by loosening the bolts that connect the yoke to
the motor. Place an accurate square so that the beam is on the table and the
blade is against the saws blade. Adjust the motor tilt to eliminate any gap.
At this point, your saw can be used for accurate woodworking. Setting
accurate arm and blade angles can be done by trial and error or using a
precision instrument. If you need further assistance, please don't hesitate
to send me email or visit my web site.
Thanks,
Ed Bennett
e...@primenet.com
Home of the TS-Aligner
Visit my web site: http://www.primenet.com/~ejb
bwasson
of great info was provided. I don't have the manual, but will give Sears
a call to see if they still stock it. I got it pretty close this
weekend, but will double-check the table in relation to the arm when I
get home tonight.
Thanks again,
Brian
Walter H. Klaus
Walter H. Klaus
William Prisavage
and each adjustments' success is predicated on the adjustments made prior to
it.
"Walter H. Klaus" <wkl...@gulftel.com> wrote in message
news:39C2B54C...@gulftel.com...
> ShopNotes had an article on this last month.
> Walter H. Klaus
>
> bwasson wrote:
> >