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#Post#: 13238--------------------------------------------------
Square Grinders
By: 660magnum Date: December 1, 2012, 4:52 pm
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I recently purchased a older used Silvey Swing Arm Grinder. It
was made in late 1979. It appears that the grinder has sat
around unused since the 1980's? It had gone though a couple
hands between the original owner and when I got it but they
didn't use it or harm it.
The grinder has sat around for years and apparently at the
original location got spritzed with little speckles of something
that appears to be brown mud or something from a cow when it got
up? This swing arm grinder was originally a bright red on the
main body and the arm was anodized gold. Most of this color is
gone now. Part of the pivot bearing on the swing arm was broken
by uneven pressure from a split type lock washer? I got new
bearings for the swing arm from the local Grainger outlet as
they were 1/3 the price of the local Applied Industrial
(Bearings Inc). I removed the split lock washer and replaced the
5/8" retaining nut with a self locking nut like is on the
current Silvey swing arm grinder. I replaced all the bolts with
Allen head bolts and got new springs for the stops at the local
hardware store down the street. Running the motor, the bearings
sounded good and the new grinding wheel I bought from Silvey ran
true.
The swing arm pivot bolt has adjusting set screws at the top to
cock the arm left or right. I attempted to set these screws so
the arm would be the same height from the grinding wheel on both
sides. I started to dress the wheel and one of the wing nuts
where you turn the diamond dressers (in and out) came off
because the dresser was hard to turn. The wing nut was just
attached to the dresser with J-B Weld. I put a collar on it for
now. I dressed the wheel to the angles that the dressers were
set at. They appeared to never have been moved in years and the
resulting angle on the grinding wheel came out realistic
according to what I had read.
I then made a 60DL 72LGX square (3/8" X 16"). When I swung
around to do the left hand cutters, I had to adjust the chain
stop about 1/2 turn. I was apprehensive about this but cannot
measure any difference left-right on the chain teeth. The chain
stops on this grinder are just made from 1/4" square key stock.
But many years ago, some kid messed with the grinder and ruined
the left stop by running it into the wheel along the inside edge
back about 1". I dressed the ends of the stops some with a raker
file but you cannot go back 1". So I have to hold the stops over
towards the wheel to get them to hold the chain cutter in the
right place. So it is on my list to make new stops for the
grinder some day?
The resulting chain turned out nice with a 18 degree outside top
angle and 88 degrees on the side. The inside was around 43-44
degrees. This is within the realm of acceptability for a square
chain. I measured a factory Oregon 72CL chain and I got 16
degrees on the top plate, 86 degrees on the side, and 55 degrees
on the inside top. So the Oregon 72CL as a little more lead on
the vertical and the cutting edge is more blunt. I then measured
the dressed grinding stone and the top angle was 25 degrees and
the side angle was 75 degrees from horizontal. These were the
dresser settings on the grinder when I received it and appeared
to have been in that position forever?
This swing arm grinder is a Silvey "R". There is just a minor
difference between it and and the original Simington 450
grinder. The differences are the chain holding disk has a hub
instead of a thick washer on the Simington and the squareness of
the arm's pivot bolt is adjustable on the Silvey. They have the
same motor and the stop mechanism is identical. The motor is
just a 1700 rpm open split phase Dayton motor from Grainger but
it is ball bearing.
Sometime in the later 70's, Elmer Silvey sold the Silvey Swing
arm design, patents and all, to Jack Simington. So from 1982
until this century, Silvey did not make a swing arm grinder. And
. . . Silvey doesn't have any parts for the early version either
unless there is some part from the current design that happens
to fit like the grinding wheel or the stand.
Simington went on to also make a variation of the Simington 450
that works like a Silvey Razur Sharp. Later, Simington sold the
grinder business and it went through several hands. The last
model is the 451C and the 451's have a more sophisticated arm
design. There are a few other subtle changes to the stand mount
and a hex seat for the pivot bolt head. You can still buy new
Silvey's except for the Pro Sharp. Simingtons, I understand are
made by Salt Creek Industries in Lakeview Washington but I have
not seen any new ones advertised?
At one point when Simingtons were not being made and the patents
had expired, Silvey brought out a new swing arm grinder. At
first glance, the only difference is new chain stops on the
swing arm but Silvey tells me that the center to center
dimensions are all different and the major parts will not
interchange.
I get the idea that there was never a tremendous market for
square grinders with a probable volume of a half dozen/year for
the swing arms at its peak?
The Swing arm grinder is simple. The early ones - except for the
two main castings, everything is simple to replicate or purchase
from many sources. The mounting flange for the grinding wheel
can be raised or lowered to effect different angles. The
dressing angles on the wheel can be changed to effect the top
plate angle or side plate angles. The position of the chain
holder can be moved forwards or backwards to effect the interior
vertical as well as the wheel raised or lowered to affect the
interior angles. If you study and think about all these and
perhaps write down the inter-relationships, you can make a race
chain or a work chain or change back and forth. However, there
are no degree or position markings on anything so you will have
to measure and document your angles with a angle finder.
I bought this Angle Finder at Lowe's some 25 yrs ago for $4 and
it is close enough for setting your grinder.
[IMG]
HTML http://img.photobucket.com/albums/v11/jamesirl/toolsplus_2240_35285721.jpg[/img]
If you read Masden's or Silvey's literature on the different
grinders, they refer to the Swing Arm Grinder as a entry level
grinder and if you want to make all different kinds of angles on
chain, you need the Pro Sharp. With the Pro Sharp, The angles of
the dressers have markings as does the height of the chain
holders. So with your personal documentation, and a nice angle
finder, you can also do what ever you want to with the swing
arm? The more expensive grinders have a high parts count. The
ones with sliding chain holders have potential wear points that
must be kept up with? After studying the different grinders, the
swing arm is the K-I-S-S system. If you always do the same
grind, it is a set and forget situation with nothing to wear out
except the wheel. The chain stops on these more expensive
grinders are better in that they have a notch in the end that
fits the top corner of the cutter rather than the bottom. This
serves to hold the front of the cutter down when you contact the
grinding wheel.
All the operator's manuals are available on the Silvey, Madsen's
and Bailey's websites as .pdf's. If you read the one for the
swing arm it is rather skimpy. Actually what is said is concise
and what really matters but if you are new to swing arm
grinders, you will want to know more. Have a look at the manuals
for the more expensive grinders as they go into a little more
detail and what might interest you is how to dress the grinding
wheel. Be easy with the dressers and start from the corner out.
When the corner looks dirty, it is time for a light dressing of
the wheel. Some of the cause and effect relationships are
explained in these other manuals.
If you want to get into square chisel chain grinders, you need
to be a person that studies and documents all the cause and
effect relationships
with your own grinder and the chain. Know what works and what
doesn't. Don't be like the kid at the chain saw shop that grinds
away half of every chain at the same angles and has no concept
of what he is doing and could care less.
#Post#: 13239--------------------------------------------------
Re: Square Grinders
By: Chainsawrepair Date: December 1, 2012, 5:31 pm
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Man, Thanks for all that leg work and info. 8)
Have you tested any of your square off the grinder against a
known square off something else yet?
#Post#: 13246--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 7:28 pm
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Dennis Cahoon's Simington 450 swing arm square grinder. The
picture is from the Internet.
What Dennis is pointing to in the first picture is where someone
before him milled a slot in the arm so you can change the inside
angles on the 450.
They also put a slot in the mounting plate in the second picture
to raise and lower the chain relative to the grinding wheel.
#Post#: 13248--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 7:34 pm
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[quote author=Cut4fun2 link=topic=1333.msg13239#msg13239
date=1354404715]
Man, Thanks for all that leg work and info. 8)
Have you tested any of your square off the grinder against a
known square off something else yet?
[/quote]
No I have not but measuring angles and comparing with a 20" loop
of Oregon CL that came from you, I see no reason why it would
not run good.
#Post#: 13250--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 7:41 pm
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This is my old style 1979 Silvey Swing Arm grinder as purchased.
I'll try to get my camera going with some current pictures?
#Post#: 13251--------------------------------------------------
Re: Square Grinders
By: stihlbro Date: December 1, 2012, 8:06 pm
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Wow! Cool pictures.... Does it have a stand?
#Post#: 13256--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 8:38 pm
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I bought an original stand from Silvey.
The later Simington 451's have a socket cast into the main frame
to receive a 1 1/4" water pipe with a 1/4 - 20 set screw to hold
it in place.
this makes a stand simple for you can just take an old wheel rim
or even an old tire and fill it with concrete with the pipe
square in place and you have a stand.
The Silvey Razur Sharp and Swing Arm as well as the Simington
450's just have a 1/2" bolt hole in the main frame so you need
something flat and about 4" sq and 3/8" thick to bolt the
grinder to. I didn't have any steel plate and arc welder handy
so I just bought a genuine Silvey stand. I had a stand on hand
but the top plate is only 1/8" and there was no way to get
inside the pipe with a nut.
#Post#: 13259--------------------------------------------------
Re: Square Grinders
By: stihlbro Date: December 1, 2012, 9:12 pm
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I really like the concept of the swing arm.
#Post#: 13261--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 9:39 pm
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Old Simington 450's. Take notice that there is almost no
difference between it and the early Silvey swing arm grinder
In the second picture, the grinder is mounted on a HD camera
tripod which may have cost as much as the grinder when new?
[IMG]
HTML http://img.photobucket.com/albums/v11/jamesirl/simington450.png[/img]
#Post#: 13263--------------------------------------------------
Re: Square Grinders
By: 660magnum Date: December 1, 2012, 10:09 pm
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Simington 451A that some one butchered by cutting around the
motor bolt holes so the motor could be shimmed up or down to
change the cutter angle.
You can just raise and lower the arm to do the same thing or the
wheel can be raised or lowered. To raise of lower the wheel, you
have to remove the wheel and there is a set screw in the hub.
The hub will most likely be stuck and you will have to heat it
and use a puller to get it started moving. Keep up with where
you are at with the wheel position.
Notice the different detail on the arm whereby it can be raised
or lowered or the chain can be moved forward or backward. The
arm can pivot up and down with the bolt down underneath.
You can also see the socket for the 1 1/4" pipe of the stand.
[IMG]
HTML http://img.photobucket.com/albums/v11/jamesirl/Simington451A_B.jpg[/img]
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