Thread: LV Honing Guide Mk II – Second Impressions: Chisels

It is my intention to post a series of mini-reviews on the LV Honing Guide (Mk II) as I gain experience with it. The initial post a few days ago were First Impressions from observations made at a recent sharpening workshop I ran in Perth. The Mk II was only used on plane blades at that time. While the opinion of all participants, including myself, was very favourable, the use of parallel sided, wide plane blades is a fairly safe test for honing guides. It is the narrow, wedge-shaped chisel blades that offer the greatest challenge: will they fit, will they remain square, how thick a blade can be used, how narrow a blade can be used securely, how short can one go, and what angles may be honed? These questions are examined here.

The chisels on test

I have included a selection of chisels I own, chosen to challenge the Mk II. They include:

Japanese chisels: bench, dovetail and mortise chisels
Western paring chisels: Witherby and A E Berg
Western mortise chisels: Ward
Firmer chisels: very short Japanese chisel, very large Woodcock chisel.

Measurements

Measurements included the length of the blade, its width, thickness at entry and exit to the guide’s hold down, and the bevel angle employed.
Since all the chisels had no difficulty in being held in the Mk II for honing, and at the desired bevel angle, the defining evaluation was a rating of the stability with which the blade was secured in the hold down. Ratings of 0-5 were employed, with a 5 being the best rating (rigidly stable), 4 next (can be moved with much force), then 3 (can be moved with moderate force), 2 (can be moved with mild force), 1 (can be moved without force), 0 (cannot be secured at all). Note that all the rating are subjective (i.e. I did not measure the force applied). In my opinion, a rating of 3 is just satisfactory, a rating of 4 is good, and a rating of 5 is excellent.

Notes about the Mk II

All these chisel blades had one thing in common – they tapered. Some tapered more than others. The Mk II hold down attempts to manage this by being able to pivot as it is tightened, thus being able to provide even pressure across the full width of the blade’s face. There also appears to be a plastic lining (non-slip) inside the hold down. My feeling is that this material was not working optimally since some blades could be made to slide around (unless high levels of down force was applied through the screws). Perhaps this plastic could be made from a softer material?

The other observation is in regard to the hold down itself. I have previously noted the importance of maintaining equal pressure at each end (via the screws) as otherwise the blade will be skewed in the holder. This becomes more critical as blade become increasingly narrower. Maintaining equal pressure is achieved by eye. I found that unbalanced pressure would lead to the blade pivoting more readily in the holder, and that this would be a sign that the screws needed to be adjusted.

Results

The overall conclusion was that the greater the “wedge factor”, the more the blades were at risk for movement in the hold down. All the blades were considered to be held satisfactorally, but some were only just satisfactory.

I have included details of all measurements below for reference.

(1) Japanese chisels:

18mm wide bench chisel

60mm long blade, 30 degree bevel, 6mm entry to hold down, 6.5mm exit from hold down. Rated 3/5

42mm wide bench chisel

60mm blade, 30 degree bevel, 7mm entry, 7mm exit. Rated 5/5

3mm wide dovetail chisel

63mm blade, 30 degree bevel, 7mm entry, 7.5mm exit, Rated 5/5

6mm wide dovetail chisel

63mm blade, 30 degree bevel, 6mm entry, 6.5mm exit. Rated 4/5

9mm wide mortise chisel

65mm blade, 35 degree bevel, 11mm entry, 11mm exit. Rated 5/5

(2) Western paring chisels:

¼” Witherby - 90mm blade, 25 degree bevel, 5mm entry, 6mm exit. Rated 3/5

½” Witherby - 90mm blade, 25 degree bevel, 4mm entry, 4mm exit. Rated 4/5

¼” A E Berg - 90mm blade, 20 degree bevel, 5.5mm entry, 6mm exit. Rated 5/5

½” A E Berg - 90mm blade, 20 degree bevel, 4mm entry, 4mm exit. Rated 4/5

(3) Other Mortice chisels:

¼” Ward - 130mm blade, 30 degree bevel, 11mm entry, 12mm exit. Rated 3/5

(4) Firmer chisels:

3/8” Woodcock - 125mm blade, 25 degree bevel, 4mm entry, 4mm exit. Rated 4/5

¼” Japanese – 37mm blade, 30 degree bevel, 5mm entry, 6mm exit. Rated 4/5

Summary

A wide range of chisels were examined, extending from the flatter Western pairing chisels, to shorter Japanese bench chisels, triangular dovetail chisels, thick mortise chisels, and even a very short Japanese firmer chisel. Bevel angles included 20, 25, 30 and 35 degrees.

All chisels were managed satisfactorally, however it was noted that the greater the wedge shape, the greater the risk for moving out of square. With narrow chisels, the Mk II hold down requires careful adjustment to prevent this occuring. I'm sure that experience will provide further insights into its use (since I am likely missing something here).

Picture below of the chisels used here.

Regards from Perth

Derek