Simington #451C Square-Chisel Chain Grinder

The Simington #451C is suitable for both experienced and beginning chain grinder operators. Its is based on a simple-swing arm concept, which makes it easy to use, adjust, and maintain. It is also time-tested. Early models, such as the Simington #450, started sharpening square-chisel chain over thirty years ago. Some are still in use. Today's #451C is the newest version of this venerable grinder.

Silvey Swing Arm Grinder
Simington #451C
Square-Chisel Chain Grinder

The Simington #451C Features:

  • Reversible fan-cooled motor with sealed bearings
  • A Sturdy swing arm with needle thrust bearings pivot.
  • Adjustable diamond tipped dressers.
  • Carbide-tipped tooth locator.
  • Die-cast aluminum chassis.
  • Flex mounted work lamp with standard bulb socket.
  • Tripod stand included.
  • Made in USA.


The Simington 451C is a well-made chain grinder that features a die-cast chassis and swing arm. This gives it the fit and finsh of a precision grinding tool. It also features a high-quality 120v motor that is reversible and fan-cooled.

One of the benefits of the Simington design is that it self compensates for wheel wear. It does not require adjustment like the Silvey RII and SDM-4. Its simple swing-arm design compensates for wear automatically.

Compared to earlier versions of this grinder, an improved a carbide-tipped tooth locator stops the chain more accurately. However, it still lacks a sophisiticated indexing mechanism like what is used on the Silvey Pro Sharp and SDM-4. Many operators compensate for this by holding pressure against the stop-pawl. This minimizes the cutter-tooth's tendency to climb during grinding.

Like the Silvey SA and RII, it also has an arch-shaped chain mount. This is a simple and effective way to hold and position the chain, but because the chain is held on an arc, the orientation of the cutter tooth changes as the tooth gets shorter, changing an inside angle in the cutter tooth. The good news is this can be compensated for by adjusting a thumb-screw located on the bottom of the swing arm.

The Simington 451C also has economized wheel dressing mechanisms as compared to those on the Silvey SDM-4 and Pro Sharp. While they are not as stable as the ones on high-end Silvey's, they do an adquate job when the operator makes light passes and dresses in the right direction. This reduces deflection, which improves the shape and cutting surface dressed into the grinding wheel.

The information presented here is intended to make you an informed buyer. The comparisons made to more expensive grinders help you understand the differences and are not intended to discourage your purchase of a Simington grinder. This is a good machine. Hundreds of owners are completely satisfied with its performance and the performance of the chains it sharpens.

Our Advice

The Simington 451C is a good square-chisel grinder and offers excellent value. If you are looking for a new square-chisel grinder, this is it. It is the only new square-chisel grinder currently on the market.

Click here for video on setting up a Simington #451C.

Click here for a Simington #451C instruction manual.