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View Full Version : LV Mk II Honing Guide: Skew blades and further observations.



derekcohen
29th May 2005, 04:02 AM
As stated previously, I will continue adding new information about LV's new honing guide as I gain experience with it.

The blade clamp

If there is a weakness in the design of the Mk II honing guide I see it in the blade clamp. I recognize that this uses space more efficiently (that is, it extends only when needed) and is less likely to cause the blade to move out of position (as the twisting motion of the screw down on the Mk I can do), but it is more susceptible to placing uneven pressure on the blade, so causing it to be slightly tilted on the base. This would lead to a skewed grind/hone. Careful adjustment (that is, equal pressure on each side) is necessary. Having said this, the issue is more pertinent to narrow blades, such as chisel blades. In practice, I did not experience this to be a problem with plane blades or wide chisel blades (of at least 1” and wider).


Cambering blades

The wide wheel of the guide provides excellent stability (and probably reduces some wear on waterstones) and the blade will not cant over as easily as, say, an Eclipse guide. However, honing a camber on plane blade can still be achieved, and this is done by using downward finger pressure on the bevel.


Registering on right side

The blades register on the right side (bevel up). This suits most planes and chisels. It is ideal for a #140 skew block plane


Setting up for skew blades

While there is no apparent provision made for honing skew blades on the Mk II, I have included a slight modification and related methodology that will made this a doddle. See picture 1, which is the Mk II set up with the blade from my Stanley #140 skew block plane.

After a little experimentation, I determined that the 17° (green) mark coincides with a 25° skew bevel, and the 13° (green) mark coincides with a 20° skew bevel. (see picture 2). To set up the registration guide, the following must be done:

1. Mark a horizontal line across the registration guide with masking tape (picture 3). You can see (in Picture 4) that the skew blade is set up in the same way as any other square blade.
2. Mark off the guide lines for 25° and 20° on the registration guide (picture 5).

Picture 6 demonstrates the final set up.


Chisel vs plane blades

So far my impression is that the Mk II is a superior quality honing guide with plane blades. It is capable of a satisfactory performance on chisels, but narrow blades certainly cause this is to be a more demanding process. This is largely due to the nature of the blade clamp. My experience is that the Mk I is capable of greater down force on the blade, but (and it is a BIG “but”) the Mk I is not in the same league for ease of set up, and the Mk II is capable of clamping a much wider range of plane and blade sizes (both in terms of width and thickness). One differences in design is the width of the bed (I have no other technical term for this part) on which the blade rests, with the Mk I being about twice the width of the Mk II. This may be a double-edged sword since, on the one hand, it may provide less support, but on the other hand it makes it possible to clamp short blades (such as Japanese chisels), which the Mk I does not do as well.

Regards from Perth

Derek

derekcohen
29th May 2005, 04:04 AM
Here is Picture 6.

derekcohen
29th May 2005, 01:20 PM
Rob Lee has confirmed that a separate registration guide will be available for skew blades. The reason for this was to keep down the price of the basic Mk II guide.

Regards from Perth

Derek