To scrub or not to scrub?

[ro]

I've been reading this fantastic forum for a month or so now and wondered if I could intrude and ask a (hopefully simple) question.

I'm about to start work on building a chest out of oak, which is going to require a fair bit of gluing and smoothing boards.

I'm planning on using a Record No 5 plane for the initial levelling and then a Stanley No 4 for smoothing afterwards (both of which were picked up for about 2 quid and have had their soles flattened and blades sharpened).

Would I find it easier to do the initial levelling if I ground a blade for the number 5 into a scrub profile? Does this make it easier to take larger cuts?

If so, where could I pick up a spare blade and cap iron?

Thanks for all your help

 

[Racers]

Hi,

Welcome

You have two planes that have the same size blade, so camber one and leave the other one straight.

Pete

 

[Paul Chapman]

It really depends how much material you want to remove. A proper scrub plane has the blade ground to something like a 3" radius and will remove a lot of material very quickly and leave a series of deep furrows and maybe some tear out which will all have to be cleaned up. If you are working with sawn wood and just want a fairly easy way to get it smooth, a far gentler radius might be better.

Personally, for this type of job, I've gone over to using a toothed blade

You can remove a little or a lot of material depending how deep you set the cut, you get no tear out and can flatten boards with just a light criss-cross pattern left which is easily removed with a normal plane. You can get the toothed blades for bevel-up or bevel-down planes.

Here's a clip of Deneb from Lie Nielsen using one

http://www.youtube.com/user/LieNielsen# ... pxKo1vjOwA

Cheers :wink:

Paul

 

[ro]

Ah, excellent idea about using my existing blades and swapping them between planes - I don't know why i didn't think of that

What kind of radius would be good for levelling sawn wood? About 6"?

That toothed blade looks really good - are they as easy to sharpen as normal blades?

Thanks so much for helping a clueless newbie with all this!

 

[Jacob]

If you are just doing typical new sawn boards then "scrub" doesn't come into it. A scrub plane is for deep scooping cuts on bad surfaces e.g. cleaning up old joists - the deep cut is mostly in the cleaner wood underneath, leaving the grit, old paint etc in the shavings- so minimising blade wear. Or for rapid removal of rough timber to something more level. Basically an (inferior?) alternative to the axe or adze.
The difference between a 4 and a 5 isn't a lot so to make it meaningful you could set up the 4 as a smoother i.e. very sharp, close up mouth, fine set and steep bevel if there is tear out. On the other hand, as a beginner this might be too much, so perhaps just get them both sharp and use them alternately, to get your hand in with planing practice.
Either way a bit of a camber on the blade (nearly all plane blades IMHO) is a good idea.

 

[woodbloke]

I've just bought a new scrubber from Deiter Schmidt and I've been amazed at just how quickly they'll remove material. As Mr Grim rightly mentions, the cut is narrow and very deep and is ideal for removing the top surface of a new board or an old surface which might be engrained with dirt or grit. There isn't any reason why you couldn't keep on going to get reasonably close to the finished dimension, but there is the danger of 'tear out' which isn't too important if your some way from the finishing line. The way to remove lots of timber (if you have to plane by hand) is to use a woodie:

with a cambered blade so that it'll take off a decent thick shaving...then use your No5 with a straight blade (corners knocked off though) to refine this surface and finish on the line. The pic shows a woodie with a convex sole and a pile of shavings that took 15 minutes to remove...try that with a toothed blade!

Toothed blades work well, but there are other alternatives just as effective, but Paul is right, it does depend on how much you need to remove and how quickly you need to do it - Rob

 

[Jacob]

Hmm Rob and others keep agreeing with me, I must be losing my touch!
I wouldn't do straight edge with corners knocked off though, it just means less obvious tramlines, but still lines. Camber every time.

 

[Alf]

Hell's bells, Rob, you should have checked that board as you planed - gonna take you ages to get it flat now... :wink:

As regards the amount of camber, bear in mind the more you have for one stage of the planing process, the more you'll have to remove with the lesser camber in the next stage. So if you give your jack a really aggressive camber, moving straight to the negligible camber of a smoother will give you a lot of work before you're taking full width shavings.

 

[Paul Chapman]

That toothed blade looks really good - are they as easy to sharpen as normal blades?

Yes, easy to sharpen. Just hone the bevel side as you would a normal plane. Best not to wipe off the burr on the flat, toothed side, as you don't want to wear away the teeth. I just wipe the edge through a piece of softwood to get rid of the burr.

If you use one in a bevel-down blade, shavings will get trapped between the blade and the cap iron because of the gaps caused by the teeth. I overcame this by setting the cap iron back a fair way as you can see in the picture

In order to maintain normal adjustment of the blade, I had to grind a little from the end of the cap iron.

I bought my blade from Dick in Germany http://www.dick.biz/dick/product/703160/detail.jsf


Cheers :wink:

Paul

 

[woodbloke]

Hmm Rob and others keep agreeing with me, I must be losing my touch!
I wouldn't do straight edge with corners knocked off though, it just means less obvious tramlines, but still lines. Camber every time.

There are occassions Jacob when I do agree with you, but they don't happen very often :wink: :lol:
Without straying too far from the OP's point, the pics below:

show a veneered oak surface planed with a LV BU smoother using a straight blade with the corners nicely rounded off. Although it may be a little difficult to see from the pics, there are no tramlines. A slightly cambered blade will give the same effect, however the straight blade will do the same thing provided a dead parallel shaving is removed.
However, if the blade's not set correctly, you're in trouble :shock: - Rob

 

[ro]

Ok, so a slight rounding off on the edges if a normal blade is good. Would I be aiming for relieving the edges by about 1 mm?

I do have a wooden jointer too (I almost typed I have a large woody but I resisted the urge). What kind of camber would be good for flattening surfaces, not gouging through loads of bad wood and paint?

 

[woodbloke]

Ok, so a slight rounding off on the edges if a normal blade is good. Would I be aiming for relieving the edges by about 1 mm?

I do have a wooden jointer too (I almost typed I have a large woody but I resisted the urge). What kind of camber would be good for flattening surfaces, not gouging through loads of bad wood and paint?

Rounding the corners on a straight blade by around a mm is about right. Describing the camber on a blade is difficult, but it's sufficient when sighted along the sole of the plane to see that it's definitely curved as opposed to straight, but quantifying by just how much is tricky...if one were to say that it's higher in the centre by around .5mm that might be coming somewhere close to the mark - Rob

 

[Jacob]

I've just bought a new scrubber from Deiter Schmidt and I've been amazed at just how quickly they'll remove material. As Mr Grim rightly mentions, the cut is narrow and very deep and is ideal for removing the top surface of a new board or an old surface which might be engrained with dirt or grit. .....

I worked that out when I realised I'd been "scrubbing" with my PT: I use a lot of reclaimed timber and trying to shave off a painted surface through a thicknesser blunts the blades in no time. Instead I set it deep to remove a good thickness including all the paint (or grit etc) and a few mm of cleaner wood, in one pass.

 

[ro]

Rounding the corners on a straight blade by around a mm is about right. Describing the camber on a blade is difficult, but it's sufficient when sighted along the sole of the plane to see that it's definitely curved as opposed to straight, but quantifying by just how much is tricky...if one were to say that it's higher in the centre by around .5mm that might be coming somewhere close to the mark - Rob

Wonderful! I'll give it a go tonight. Thanks to everyone for all the great advice.