A Simple Sharpening Guide

Some time ago, I purchased a roller ball, inserted in a cylinder and having a screw for fixing it into the wood. I tought to a sharpening guide like Record 161, and today, finally, I decided to realize it.
Construction is easy and requires little time.
Necessary:

Two hardwood pieces cm 12x4 ca., one piece cm 10x4 ca., 1 cm thick.
Two M5 or M6  brass coutersunk bolts and their wing nuts and washers.
Bore together, onto half line, one 12 cm piece and the 10 cm piece, so to have a 8 cm distance between the holes. Countersink holes in the 12 cm piece.

The bolts are blocked by gluing the third piece.


 

When the glue is dry, the roller ball is screwed at center, under the guide. That is!
This guide can hold skewed blade and, having only one point touching the surface, allows to sharpening cambered blades, like scrub plane blades.

For setting the wished angle it is useful to have a reference board, by which is possible to find the searched value simply laying the front of sharpening guide on the board edge.

If the chipbreaker does not adhere to iron....

Is ......
likely that the thin chip is stopped between the two irons with
resulting plane mouth clogging. It is therefore necessary to carefully flatten the surface portion  of the chipbreaker that 
adheres to the blade and ensure a perfect fit between the parties. The problem is that sometimes (if not frequently) the chipbreaker is not regular and after the iron screw has been tight the
blade may show non contact areas, despite having flattened with
care.  Being soft iron, we can try to straighten the chipbreaker in the vice but this is a little difficult job. 
Another method is to create a burr on the chipbreaker edge, by which we can close any (small) residual gap. The procedure
plans to keep the chipbreaker with an angle respect to a flat surface on which we attack a sheet of 150 grit abrasive paper. Move repeatedly backwards until the metal burr forms. So
use a small screwdriver (electrician models have
the right thin measure) and pass it along the contact line between the two iron until they adhere perfectly.
The process takes few minutes!

   

Sharpening a Scrub Plane Blade

The  scrub plane blade has an arc-profiled cutting edge, with  more or less  marked radius according to the job required. This profile makes it more difficult to sharpening by guides so many people prefer sharpening it by hand.

I'm not very good at this job, so I searched for sharpening guides available that could serve the purpose. The Record 161 is a guide which is easy to find on ebayUK for few  pounds. It has only one central contact point (a rolling ball in the middle) and this permits to incline to the right and left allowing to follow the cutting edge profile easily.

The  blade is held firmly in place by a clamp screw that allows unrestricted iron orientation, useful even if it was necessary to sharpen skewed blade. The  dark side is that you have to ensure the correct blade position by hand.

For bigger curves the guide can be moved to the sides of the sharpening stone to allow for greater tilt, as seen in the short movie. The result was satisfactory with 35 ° bevel. To re-sharpen exactly to the same  angle I'll use a simple self made jig.

Plow Plane Blade Sharpening

After years of woodworking by hand and using hand tools, I’ve realized that the variety of blades requiring sharpening is so broad that relying on a single guide is impractical. In short, there’s no such thing as a universal guide! So, I’ve acquired several different devices that allow me to securely hold most blades during sharpening. For plow plane blades, I prefer the Stanley guide. Its rear support compensates for the narrow width of the cutting edge, preventing the device from tilting to one side and ensuring a perfectly square edge—which is essential for this type of blade."

"However, the Stanley guide was originally designed for chisels or wider blades. Metal plow blades are thin, making it difficult to tighten them securely. To solve this problem, I place a small wedge between the blade and the lower part of the guide. This provides a firm grip without compromising the stability of the setup during sharpening.