84Engineering - Plunge Platen

(2 reviews) Write a Review
Gift wrapping:
Options available

Bulk discount rates

Below are the available bulk discount rates for each individual item when you purchase a certain amount

Buy 2 or above and pay only $149.00 each
  • 84Engineering - Plunge Platen
  • 84Engineering - Plunge Platen
  • 84Engineering - Plunge Platen
  • 84Engineering - Plunge Platen
  • 84Engineering - Plunge Platen
  • 84Engineering - Plunge Platen


84Engineering Plunge Platen for slow-speed grinding

** See options to select either 6 or 19 mm wheel diameter **

  • replaces the standard, flat platen
  • used to grind plunge lines 
  • Run at SLOW SPEED
  • adjust angle until sanding belt breaks over back corner of platen - no gap between sanding belt and platen to avoid stabbing blade through belt for a bad day
  • for best result: read the instruction PDF and move the bracket to the right holes for your grinder model (2x48" or 2x72" 84Engineering grinder)
  • Can also be used upside down, running the grinder in reverse.

The 84 engineering 6mm or 19mm plunge platens make the otherwise intricate task of grinding plunge lines and rounded corners simple and repeatable.

Our plunge platens use either a 6mm roller or 19mm small wheel rather than a radiused edge for reduced friction. This equates to cooler grinding and increased belt life.

Designed to provide the best finish on your knife, there is minimal gap between the roller and the radiused edge of the platen.

The result of this is that the 84 Engineering radius platen will leave no discernible transition between the wheel and 215 mm flat platen, keeping hand sanding to a minimum if required at all.

We recommend the 6 mm plunge platen for thinner blades and the 19 mm for integral bolster style blades. Our plunge platens use our standard 19mm spigot, so will easily swap out with the included platen on either the Shop Mate 48” or Shop Master 72” belt grinders – using the standard tooling arms. You can also use the plunge platen with a 84 Engineering small wheel arm, resting the back of the platen on the 2" idler wheel. Threaded holes on either side of the plunge platen allow for the spigot to be mounted to either side. This means the plunge platen can be used with the platen facing up or down depending on application or preference.

Please note, due to the size of small wheels they should not be run at full speed on variable speed grinders. On our Shop Mate and Shop Master grinders they should only be run in the slow, green zone of your speed controller.

We recommend the use of light backed belts with these small wheels as heavy X and Z weight belts do not easily bend to such a tight radius.

 Plunge platen PDF instructions: LINK

The instructions: The plunge platen or "waterfall platen" has a bracket that goes into the tooling arm.

The bracket can be attached in 3 different locations - it comes in the middle position.

For best results, move the bracket to the front holes closest to the wheel for 2x48" Shop Mate and to the back holes further from the wheel for the 2x72" Shop Master grinder. (see photos on this product page, or the PDF instructions linked to on this page)

View AllClose

2 Reviews

  • 5
    Plunge platen

    Posted by jai on 25th Dec 2023

    84 Engineering knock it out of the park again. These things massively reduce handsanding and give crisp, consistent plunges. Huge fan.

  • 5
    Great tool

    Posted by Jack on 25th May 2023

    This has cut hand sanding time down even further and is very useful for clean radiused plunge lines. I Highly recommend it. As always, postage was fast, great work.

View AllClose