I know the following plane doesn't 'look' ideal, but its the concepts behind it that are, I feel.
Because the ideal plough is yet to be made in my opinion, I've modified an old 45 in an attempt to own one. And its turned out to be the most reliable plough I've ever used....ie. no annoying surprises. Consistantly works how I want it to. No stuffing about.
Here it is, along with its modified blades, and setup tools. I've labelled the mods.
Its all about obtaining an accurate plough cut. A common cut, but yet still quite tricky to get them spot on with a regular plough plane. Which tends to make the powered router attractive eh.
More often than not my results are substandard with a regular plough....ie. those shoulders arn't crisply cut at 90 and the plough floor isn't square. and its not entirely my fault ! .....the plough plane designs are to blame as well.
Seems the best way to try and describe what I think is the 'ideal' plane, is to run through how I tuned this old 45 ..... Hopefully, I'll be clearer that way.
First, I'll introduce this setup block I recommend you make. Or something like it..... It allows you to easily check your planes settings.
Add a deep fence face first....A deep fence face I've found when rubbing off a deep timber face will provide excellent stability.
Fence setup now......Now have to make sure the skates both run perpendicular to your new fence. Often there a little off, which will only affect accuracy.
If theres a gap anywhere between the skates and block, you've got a problem... I think you should really lap your planes skates square, until its all gapless.
The technique I use is with a squared block of thick timber......spray adhere the sandpaper down.....and whilst running that fence tight against the wood(always), the skates run on the grit,,,,taking the high spots off, just like lapping a bench plane..
Fence and skates ok........now the blades.
Flaring the blades
IMO all plough blades should flare. Meaning, the width of the blades edge should be wider than the rest of the body further up.... Really makes all the difference I've found.
Old wooden plough plane blades seemed to have it....but modern ploughs like my 45 seemed to skip the concept unfortunetly.
Without it, you've got a caustrophobic environment for your plane.
I feel you can understand the problem better by relating it to what it feels like using a hand saw without enough set. There prone to bind up in there own kerf. To fix the problem you put more set on the teeth and the saw will work better because the width of the cut (kerf) is wider than width of the saw body above it.
Well, I see a plough cut as being similar to a saw cut in that respect. A plough blade that doesn't flare; thats just a rectangular blank, is like trying to handsaw without enough set.
Flared blades wouldn't improve things I'd imagine, if we all moved like robots. But we don't. And particularily when we are pushing the plane with the fence rubbing a thin edge(or using a very wide blade), we're prone to wobble the plane off vertical a little. Like this sort of thing.
For combination planes, with multiple skates like the stanley 45, 50..etc flared blades I've found are a godsend....because the skates grip the blade closer together. This tends to solve a lot of those fiddly alignment problems of fence and skates. The plane just has more freedom to move.
If you decide not to to use flared blades you must be extra careful to ensure skates and fence are all in parallel with one another. Even say 1mm askew and you risk a jam up...so use callipers.
Anyway, this is how I ground my plough blades flared.
more next post...