Author Topic: Square Grinders  (Read 5970 times)

0 Members and 0 Guests are viewing this topic.

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Square Grinders
« on: December 01, 2012, 05:52:01 pm »
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 **** 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.


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.

 
 
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Social Buttons


Offline Cut4fun .

  • Administrator
  • Nitro Hotsaw
  • *******
  • Posts: 18266
  • Karma: 346
  • OHIO REDNECK Saw Repair Getter Done
    • Redneck Chainsaw Repair
Re: Square Grinders
« Reply #1 on: December 01, 2012, 06:31:55 pm »
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?
REDNECK Saw Repair Getter Done

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #2 on: December 01, 2012, 08:28:15 pm »
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.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #3 on: December 01, 2012, 08:34:58 pm »
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?

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.
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #4 on: December 01, 2012, 08:41:25 pm »
This is my old style 1979 Silvey Swing Arm grinder as purchased.

I'll try to get my camera going with some current pictures?
We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline stihlbro

  • 4 cube
  • **
  • Posts: 70
  • Karma: 8
  • Location: virginia
Re: Square Grinders
« Reply #5 on: December 01, 2012, 09:06:16 pm »
Wow! Cool pictures.... Does it have a stand?

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #6 on: December 01, 2012, 09:38:06 pm »
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.

We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Offline stihlbro

  • 4 cube
  • **
  • Posts: 70
  • Karma: 8
  • Location: virginia
Re: Square Grinders
« Reply #7 on: December 01, 2012, 10:12:08 pm »
I really like the concept of the swing arm.

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #8 on: December 01, 2012, 10:39:32 pm »
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?

We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

Online 660magnum

  • Global Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 6387
  • Karma: 231
  • For The Love Of Chainsaws
  • Location: NCO
Re: Square Grinders
« Reply #9 on: December 01, 2012, 11:09:05 pm »
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.

We should share what we know... someone may learn...
That knowledge can live after us... and that "Pays It Forward".
Be all that you can be . . .

 

Related Topics

  Subject / Started by Replies Last post
177 Replies
4392 Views
Last post March 04, 2016, 04:45:17 pm
by dutchsawdoctor
3 Replies
287 Views
Last post October 26, 2012, 05:14:03 pm
by Playinwood
22 Replies
439 Views
Last post January 02, 2013, 07:03:13 pm
by mdavlee
2 Replies
386 Views
Last post February 10, 2013, 08:09:53 pm
by Al Smith
26 Replies
555 Views
Last post October 26, 2013, 10:51:48 pm
by HolmenTree
14 Replies
373 Views
Last post December 25, 2013, 01:07:42 pm
by Cut4fun .
2 Replies
240 Views
Last post May 03, 2014, 12:47:51 am
by 660magnum
20 Replies
218 Views
Last post December 20, 2014, 06:12:22 pm
by 660magnum
28 Replies
711 Views
Last post December 14, 2015, 12:05:10 am
by Philbert
3 Replies
181 Views
Last post December 13, 2015, 11:47:19 pm
by Philbert