Thread: $2 scrub plane

I have recently started to find a use for a scrub plane, and found Paul Sellars video a little while back:

Making a Scrub Plane - Convert your Stanley - with Paul Sellers

I have a couple of useless Russian "I can't believe it isn't a #4" planes that I am considering converting to other uses, and can do so without feeling bad about ruining "historical" value or some such.

I've also been admiring a friend's Carter #1C (Stanley #10ish) plane that I might convert one of my Russian clunkers using some advice from a fellow called Stumpy Nubs.

Craig

Originally Posted by chook

...... I suppose that if I spent up and bought a shiny new scrub plane from LV or LN then it would work even better but for what it is and what it cost it is fine......

Chook, I used a scrub just like yours for many years and was pretty happy with it, too. Why I bought a new LV, I'm not quite sure, but I think it had something to do with a sudden rush of blood to the upper part of my anatomy at the precise moment I had a bit of discretionary cash jingling in my pocket.
I think the dedicated scrub is a bit of an advance over a modified #4 (but not until I replaced that abomination LV call a tote, with a proper handle!). Given the outlay on your conscripted #4, I reckon you are getting vastly more bang for your (2) buck(s)!

Before I got the LV scrub, I had intended to replace the blade in the #4 with the thickest blade I could find. These planes operate with a lot of blade overhanging the support, which is a great way to induce chatter in a thin blade. The thicker the blade, the less of a problem this should be. I reckon a very thick blade should bring the performance up to just as good as any dedicated scrub. You may not be able to use the depth adjuster if the cam can't reach through to engage the cap iron slots, but it's a pretty minor inconvenience, since these are generally 'set & forget' planes. I didn't get around to trying a very thick blade, so it remains just a theory until someone does the necessary experiments.....

Cheers,

I just checked what I wrote. I meant 3/32 inch not 3/16 inch. It is a plane not a chain saw.

Secondly I was motivated to make a little scrub plane for three connected reasons.
Need. I have some camphor slabs which are too wide for my planer and I would be sad to cut them.

Then at a saw making day at Ian's house I saw that he had already done a conversion and it looked good to me.

Then I saw the Paul Sellers video.

My my tool budget is destined for a scroll saw next week so lashing out on a LV plane was out of the question at the moment. But to be honest I can see no reason why I would now pay for a new one.

Chook, with a 7" radium, that is more of a short jack plane than a scrub plane. Try regrinding the blade to a 3" radius ... THEN it will be a scrub plane!

Regards from Perth

Derek

Three inches! I would have modify the chip breaker substantially or the blade will extend way out of the sole of the plane. Three inches? I will find an old blade and see what happens. I thought 7 was radical.

I thought Paul Sellars recommended an 8 inch radius. I'd expect a 3 inch radius would cause a converted plane to chatter like a chimp with a caffeine problem!

Craig

I thought he said 7 1/4 inch. But whatever it was it was not 3 inches. What Derek says about three inches is not possible in a converted Stanley I think. Möbius is correct. With the standard thin blade chatter would be a problem.

Dedicated scrub planes have no chip breaker and a blade much thicker than my plane has. If I put a three inch radius on it the chip breaker would sit way back from the edge. Not only would chatter be a problem, but without major surgery the blade would extend far beyond the sole of the plane. Even at 7 inches I had to take a bit off the corners of the chip breaker.

On his excellent site, Derek has much to say about the advantages of a true scrub plane over a mongrel like mine. After his "3 inch" post I found it and read it with interest. Maybe I will reconsider and get a dedicated scrub. I have not had enough time with my new toy yet to say if it will satisfy me.

Originally Posted by chook

I thought he said 7 1/4 inch. But whatever it was it was not 3 inches. What Derek says about three inches is not possible in a converted Stanley I think. Möbius is correct. With the standard thin blade chatter would be a problem.

Dedicated scrub planes have no chip breaker and a blade much thicker than my plane has. If I put a three inch radius on it the chip breaker would sit way back from the edge. Not only would chatter be a problem, but without major surgery the blade would extend far beyond the sole of the plane. Even at 7 inches I had to take a bit off the corners of the chip breaker.

On his excellent site, Derek has much to say about the advantages of a true scrub plane over a mongrel like mine. After his "3 inch" post I found it and read it with interest. Maybe I will reconsider and get a dedicated scrub. I have not had enough time with my new toy yet to say if it will satisfy me.

Well Chook, I think the old adage 'suck it & see' applies here. The plane I showed you & which had served me well enough til I bought the LV had the blade radiused to 3". Yes, there is a lot of exposed blade, but there was surprisingly little chatter, and I didn't alter the cap iron, just set the blade so that the edges were level with the cap iron. My 'mongrel' had no trouble handling Ironbark and other bone-hard woods it was applied to, & it positively ate Camphor laurel, removing chips ('shavings' is hardly appropriate for the chunks a scrub plane rips out) around 1/4" deep at the centre, with ease.

The thicker blade on my dedicated scrub plane does feel a bit more solid, but as I said, the difference isn't as striking as you might expect - you may have trouble picking which is which blindfolded, if both are sharp & set for a reasonably heavy cut.

Cheers,

Derek says 3. Ian says 3. Then 3 it is. It is off to the grinder I go.

I think the radius needs to suit the width of the blade. Just how much wood can a mere mortal scoop out. On a No4 3''radius would be cutting quite deep. A proper scrub is a narrow plane so 3'' radius is ok there. An old stanley No3 would be a closer to a scrub plane width. If you have any more old blades perhaps try one with a tighter curve and see how it goes. I made one from an old German style horned woodie. Not sure the exact radius as I just eyeballed a curve when I ground it. Has no chip braker so less of a fiddle there. Works fine and cuts as well as a real scrub plane. I later picked up a secondhand stanley scrub and with it's propper handle is easier on the hands to use although does not do any better a job than the converted woodie. The cost of a new LV scrub is a tad on the steep side so converting an old clunker ticks all the boxes and has to be in line with the shed code.
Regards
John

Originally Posted by orraloon

I think the radius needs to suit the width of the blade. Just how much wood can a mere mortal scoop out. On a No4 3''radius would be cutting quite deep.

Nope, John, radius is radius. The tighter the radius, the easier it is to scoop out chips.

With the converted #4, I took approximately the same width & depth of chip as I do with my LV "son of sixty two". You simply expose the right amount of blade to cut the chip size you want, or more realistically, what you and the plane can cope with. It will be roughly the same size whatever the blade width, you'll just have more blade inside the plane that doesn't get used. Perhaps it would help if we don't think of a scrub plane as a plane in the ordinary sense, but as a depth-restricted adze. Like an adze or gouge, it works best cross-grain, parting the fibres & chewing out big chips, which are more or less continuous, instead of the many scoops an adze or gouge leaves.

Cheers,

Originally Posted by IanW

Nope, John, radius is radius. The tighter the radius, the easier it is to scoop out chips.

True, but the wider the blade, the higher up the 3" radius hits the sides of the iron. And when you're dealing with a plane with a cap-iron, that becomes a problem, as the cap-iron can't be located too high up or you loose the use of the depth adjuster.

Maybe the answer is to radius the central 1" to 1.5" (the width of a true scrub) and then run the rest of the edge at a tangent. After all, very few of us would be cutting with more than the central inch or so, on a 3" radius iron...

Cheers, Vann.

Vann, the issue is that to remove waste rapidly one must take thick shavings. The thicker the better. A large radius blade will take a wide shaving, and this limits how deep one can go. Wide = shallow, narrow = deep.

The question is "do you want a jack plane or a scrub plane"? A #4 with a jack-style blade is neither jack nor scrub. Too short to be a jack and too wimpy to be a scrub.

So, if you want a scrub on a #4 body, then sacrifice the chip breaker - grind it shorter and to the same curvature. As it happens, I did this with a #5 1/2, which has a 2 3/8" wide blade. That was my scrub plane until I got the LV.

I actually do not use a scrub plane very often. I am more likely to turn to a jack plane with a 8" radius blade. Note, however, that this is 15" long.

One I built (with a 2" D2 blade that is 5/16" thick!) ...



and a Bed Rock I restored ..



Unless you are removing a lot of waste, I think most would find more use for a jack with an 8" radius blade.



If you are going to remove 3/8"+ of board thickness, and are not a confirmed dyed-in-the-wool-neanderthal, then use a bandsaw!

Regards from Perth

Derek

I have a band saw and a table table saw with a 12 inch blade. If I have to do any serious thicknessing I use machinery. All I wanted was a plane to flattened boards a bit faster. I can get 3/16 inch shavings easily with the little plane and that will do me.

For wider boards I take a 100 mm cut on both sides with my table saw and cut out the middle with a hand saw. Then I clean up the panel with hand planes. But this is a rare event. How often do in get hold of boards wider than 300 mm that my little thicknesser can handle. Not often. Sometime though it is fun just to plane timber regardless of the available machinery. My workshop time is limited so I mostly do what works fastest.

I really cannot justify the expense of dedicated scrub plane that would sit I around unused for weeks at a time.