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To be clear and if anyone read my post I never said one was better than the other. Just like glues, different methods have their place. I never implied one method was better or whatever, I objected to the statement that hand planing and sanding were the same. BTW chatoyance has nothing to do with hand planing. Chatoyance is a characteristic of the particular wood. Hand planing rather imparts a sheen like a sharp gouge or knife does. It is not magic, one can demonstrate it to ones self easily on end grain. Cut end grain with a sharp knife and sand end grain, file end grain and observe the results. They are just different, it is up to everyone to decide what method to use when.
L.

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Cut to size.....Beat to fit.....Paint to match.

This is the reason for this thread and my interest in working tops with planes and possibly scrapers. Its a look you cannot get with sandpaper.

I really like the look of wood smoothed by a plane. I made my first 3 with hand planes... Then I bought a drum sander and have never looked back.

Unfortunately - the guitar world is accustomed to and demands flat, smooth, shiny finishes of the sort obtained by sandpaper...

While tangential to the topic at hand - I found I like a plane better for jointing if for no other reason than the planed surface doesn't lie about whether it's true or not. Sanding leaves a mush behind.. This mush squishes - and it can give a false sense of the perfection of the jointed surface.... Are these sanded joints inferior? US Government tests on wooden propellers say yes - though I have not had a top or back joint fail - either planed or sanded. I have had the wood around the joint fail because I picked inferior wood (too mushy and bug eaten).. But that's no fault of the jointing method.

I planned down two spruce tops last fall that had light curl. I stropped the blades with the leather strap after sharping, but I got fine tear out. So I sanded them down. I know I can get great results with sanding and plan a French polish finish.
I love the hand plane look but it is very difficult with curly grain. I see It as a risk with thin work in general. Hence my post.

Very sharp is a good place to start.

"I love the hand plane look but it is very difficult with curly grain. I see It as a risk with thin work in general. Hence my post."

I agree BOB,
A less than perfectly set hand plane can tear out wild grain. A drum sander can accurately thickness a top with less trouble. If you like the "hand planed" look you can get pretty close using a card scraper on the sanded surface. It may not be exactly the same because the thickness sanding will be a bit more uniform than what most of us can achieve with a hand plane.

All done with a well set up, sharp, high angle plane. Top thickness is something less than 2mm (Smallman style CF lattice bracing).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

May I ask, Trevor, what are you seeking to convey with your post, where you quote Bob's decision to play it safe with his work?

Andy

Quote from Bob:

Some encouragement for Bob, in that if he wants to use edge tools, that it's entirely possible to plane very curly grained wood to low thicknesses successfully and with no more risk than normal with the right tool for the job; namely a well set up, sharp, high angle plane. That's how I thicknessed all the panels on the Koa guitar shown. I don't have a thickness sander. Ultimately, of course, it's up to Bob to choose whichever method he's most comfortable with.

A bit more back story:

All the front and back panels for that guitar were consecutive slices from the same billet, so the back looks just like the top. The wood was supplied by the customer and there were no replacements for panels that couldn't ultimately be used. When you start into a thicknessing job like that, you have to know that you will come out the other end successfully. I'm as risk averse as the rest of you! And the chatoyance seemed to work out OK, too.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

"Some encouragement for Bob, in that if he wants to use edge tools, that it's entirely possible to plane very curly grained wood to low thicknesses successfully and with no more risk than normal with the right tool for the job; namely a well set up, sharp, high angle plane."

It's always nice to see what can be done with the right tool and the expert hands using it. It gives us something to strive for, even if not something to try as a novice.

Note that Mr. Gore stated that the plane he used was high angle. In gnarly grain it helps tremendously if the blade angle is 50-55° and I have seen higher - a standard frog is 45°. It used to be that you had to get these planes from ENgland or make your own, but Lee Valley now offers these:

http://www.leevalley.com/US/Wood/CustomPlane2.aspx

Another option would be to but a shallower bevel on a bevel up plane like a block or a Stanley 62 or 64 equivalent, but I have never tried this and don't know how it would work.

Ed

If you control tear out with an extremely close cap iron setting on a bench plane (.005"-.015") you will:

1) not have to buy a bevel up plane.
2) not have to put back bevels on your irons.
3) not fight the extreme cutting resistance high cutting angles produce (especially important on thin work).
4) your edges will last longer.

Tight throat openings are not necessary.

Put a 30 degree edge on a bench plane and get the light just right so you can set the cap crazy close.
You will no longer fear wild grain.

My weapon of choice is a "garage sale" Bailey #6 which I modified to 60° blade angle. I also have a bevel up Veritas which I run at 62°. Thanks for alerting me to the Lee Valley frogs.


With high angle planes used for smoothing, you're never taking deep cuts, so the cutting resistance isn't a problem. I've not noticed a difference in blade life (but I use harder after-market blades) other than I'm normally using high angle planes on hardwood rather than softwood, which does affect the edge life.

Most of the heavy stock removal on curly woods I do with a standard angle plane, planing cross-grain. Even with pretty heavy cuts this leaves a tear-out free surface, but not a "chatoyant" surface. You have to plane in-line for that, and that is where the high angle planes come in - just to put the "finish" on.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

The Japanese are the keepers of knowledge on planing wood
Enjoy.
https://vimeo.com/158558759

Thanks David. I checked the video out again to see if my recollection of it was the same as last time. Basically it was. My "take-aways" were:

1) A cap iron doesn't make much/any difference for cuts of ~ 0.05mm and less (his #1 conclusion)
2) For a cap iron to help with tear-out when taking a 0.1mm shaving, you have to set it to an accuracy of 0.1mm or better (not too near, not too far away from the cutting edge) and at a particular angle to the top of the blade, namely ~ 80°.

In my world of planing panels, I'm usually looking for a thickness accuracy of +/- 0.05mm (i.e. uniform thickness to better than 0.1mm; cube rule of stiffness and all that). I can't get that sort of accuracy by taking approach cuts of 0.1mm, so I'm approaching target thicknesses with cuts of 0.05mm or less, having done the roughing out by planing cross grain. According to the video, that would mean I don't need a cap iron at all and can use a standard angle plane, at least for that species of wood. For the usual species of (figured) wood we use, I know (as most people do) that not to be the case. Standard angle, typical cap iron position, doesn't cut it. I've tried the close set cap iron approach but found I got better/more consistent results with a high angle plane, where (having tried a few different angles) high angle means at least 60°. Maybe I wasn't setting the cap iron accurately and repeatably enough when I tried it, I don't know. It was a long time ago. With a high angle plane, I only need a setback of the cap iron of between 1 and 2mm, an easy tolerance to hit on a busy day.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

That is a beautiful guitar, great job. I know it took a lot of skill. I have been building with wood all my life. In the early 90's I became fascinated with collecting and making tools. Planes were my focus. I had great satisfaction working with them. I moved on and now I am making 3 guitars at the same time. My first ones. So many jigs and molds; make several. I love grain, so I re sawed boards and ran them through the planner to get them cleaned up and about 1/8" thick. Then the testy part to dress a finish side. I used the belt sander. Took a while but I got them there. I started on this last July, reading and making jigs, bending, breaking, dressing wood, breaking. Got two sets of usable sapele sides by October.

You have to pick your battles all through life. Right now it is finishing my first guitars. I thought of getting a drum sander and a second band saw, but I'm low on space. I'm going to sell one of my three lathes but that space is for assembly bench. I got a 14 tooth bs blade and just change out all the time. my current obsession is making my perfling, banding, and back strips from the veneers I acquired years ago for jewelry boxes; and bought this month from the store. Also, sound holes and all the you tube videos to watch about them. One of the guitars is a Weissenborn and I had to make fancy banding for it. I got a full plate so planning down my figured tops with the plane will come way down the road, if ever. I'm sticking with sand paper at this time.

Today I am tuning up my spoke shave and sticking a Hock blade in. It is thick and only fits one of them with a very narrow throat for fine work. Then I'm going to clean up my first complete sound box, so I can start with the final finish. I planed down the fret board last week and it is ready for fret slots. Plenty to do and so little time.

Now my daughter wants me to make her a get of birdcage windsors... half size; to go with the table I made my granddaughter last fall.

Mr Gore's observations and comments parallel those of my shop mates and of Mr. Frank Klausz, a gentleman that I have had the good fortune to observe a few times running through his plane tune-up and smoothing demonstration. For smooth plane shaving thicknesses of .001" or less (.025mm), the cap iron would have to be set no more than two to three times the chip thickness (depending on the stiffness of the timber) behind the cutting edge, or about .002"-.003" - the commonly cited 1/128th of an inch measurement for a fine-set cap iron is 2-3 times that value.

The thinking in our shop is that cap irons are useful for jack work, with those much thicker chips thrown up by the well-radiused blade, but are of value in dedicated smoothers primarily as a support for the section of the blade beyond the frog to prevent chatter and deflection. Modern smooth plane blades from Lie-Nielsen, Lee Valley, and from aftermarket suppliers like Mr. Hock are quite a bit thicker than those historically used by Stanley (~.075") or Record (~.080") - our bench planes in the shop show .125"-.140" thick blades - so the presence of a cap iron is much more evident on my WW2 era #3 than on the Lie-Nielsen #4 that I usually favor in the shop. We have a range of bevel-down smoothers available for use, with blade pitches from common to middle (45-55 deg). At practical shaving thicknesses for smoothing work in figured woods (.001" or less), edge sharpness - rather than any combination of cap iron setting or pitch - seems to be the primary determinant of surface quality...most of the time.

The mantra here in the shop seems to support Mr. Gore's and others assertions with regard to edge quality as the essential ingredient for success in hand planing wood - 'Start with sharp - little else matters without it'...which is true right up until the timber becomes so challenging that a high angle frog DOES make a difference. Our samples of Aussie timbers provide most of the shop's 'devil' woods - so called because they are used to bedevil us mere students, and to highlight our foolishness in believing our edges are truly sharp.

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We have become a civilization that elevates idiots, prostitutes, and clowns. Am I still to defend it? Yes, for its principles. Yes, for what it was. Yes, for what it still may be.

-Mark Helprin, The Oceans and the Stars: A Sea Story, A War Story, A Love Story (A Novel)

Hey Trevor, you obviously have a method that works well for you! LOL.

I offered the video partly for interest and entertainment but also because it was somewhat instrumental in my own move away from high angle planing.

Back in the early 90's, I picked up an unusual, large, used Japanese machine jointer ( 12+"wide, labeled Shimohora on the side). For a long time I couldn't understand why it consistently planed Douglass fir without tear out. It was annoying to joint a wide face perfectly, then run it through my freshly sharpened Powermatic thickness planer and have tear out. At the time, Brian Burns was just promoting his methods of high angle sharpening and I jumped in with both feet. As you can attest, it does work. I thought the cutting angle must be the secret of my jointer. I was surprised to discover, however, both my machines had the same cutting angle, cutter speed, etc.
From a desire to get a better finish off my thickness planer, I started putting a back bevel on the knives as Brian and others advocated. It was a bit of a sharpening hassle and the machine motor labored heavily under the increased resistance but it did let me plane Doug Fir without a brutal sanding regime afterwards. Still, nothing like the ease of my jointer. I never could figure out what the difference was.
I also adopted the high angle program for hand planes and figured the sometimes epic increase in force required was just the price of planing difficult wood without risk.

Fast forward to a discussion I stumbled on, about the video I linked to on a woodworking forum a couple of years ago. In the discussion, some were claiming great success and advocating a re-examination of the cap iron to control tear out. Not the close setting most of us have always heard about, but a really close setting. Hard to see close.
I tuned the cap iron on my #4 Stanley that I had little use for since buying a Lie Nielsen bevel up smoother. The leading top edge was sharpened to 45-50 degrees( not 80 as in the video) and a fresh,30 bevel put on the iron. I chucked up a nasty piece of swirly grained maple on the bench, braced myself for the expected heavy resistance and took a swipe. Unbelievable!

That experience gave me an idea. I walked over to my jointer and looked at the blade and there it was! Under my nose the whole time. The gib that holds the cutter in the head is extremely close to the edge. The Powermatic thickness planer's isn't and is not designed to be. The Japanese had this figured out decades ago.

To be clear, the close cap setting is not just a stand in for a high cutting angle. Separating the cutting of the fibers from the chip breaking by that tiny distance does something miraculous. And it works for thicker shavings too.

If anyone is interested, I encourage them to hunt down the discussions of the technique, scattered over the last few years at the Neanderthal forum section at Saw Mill Creek or wood central.
Just try it!

I'm not going back. I've pulled my old bench planes off the sell pile, The Lie Nielsen bevel up is gathering dust.

It seems to me that - based on the fact that the stiffness of the chip increases as the cube of the thickness - the chip breaker effect would increase with chip thickness...which begs the question as to why - with a chip that is no stiffer than a single ply facial tissue - there is any observable effect that is not an artifact of the chip breaker supporting the blade (versus turning and fracturing the chip before it causes uncontrolled telegraphing ahead of the edge).

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We have become a civilization that elevates idiots, prostitutes, and clowns. Am I still to defend it? Yes, for its principles. Yes, for what it was. Yes, for what it still may be.

-Mark Helprin, The Oceans and the Stars: A Sea Story, A War Story, A Love Story (A Novel)

High angles work. I use them all the time on small planes that don't have a chip breaker. But, when a plane is big enough to sport a breaker, I find it more practical than a bevel up plane since I've learned to set the breaker super close.
Removing saw or 80 grit sanding marks, straightening up an edge on a shooting board, or getting a small piece to dimension, I don't have to worry anymore about perfect sharpness or gossamer thin shavings.
Getting through band saw marks without tear out at .001" a pass is some slow going.

Here are some shavings more than .003" thick with a blade straight off a 20yr old 1200grit diamond plate. No tear out. Works for me.


Trevor, are you saying the guitar in the photo is a planed surface under the finish? No finish sanding after the box was closed up?

Over the last 8 months or so I actually have used planes a lot as I have burned through wood as honed my luthier skills. The first guitar was a Weissenborn. I prepared and broke 4 sets of sides before I mastered bending, all in July and August. I used my smoothing plane and belt and ROS sanders in various combinations . I used sapele I had re sawed for wood. The grain was interlocked and planning only worked on the inside face where tearout did not matter.

I have 3 block planes that I keep razor sharp and the adjustable throat set small. I used them on the sound hole and finishing up bindings. I have 2 OM acoustics coming along also and finally got the bindings fitted successfully last Friday. I had to remove them twice because of gaps.

Then I got out my block plane and leveled the bindings up . Here is a picture showing the mess I made. The spruce top is THIN ; 5/64 - or so here at the tear out. There is no wood to sand it out.

I thought I was careful but 3 spots look like this.

I will sand out what I can with 220-320 paper.

Did you note the run-out direction before this Bob?
I've accidentally planed in the wrong direction and experienced similar tear-out

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

Top and back finished mainly by planing, with a little scraper work on the bindings; sides thicknessed with planes, bindings leveled with scrapers. Binding edges rounded over with sand paper. I try to avoid sanding because of the atmospheric dust it creates and because sanding dust gets packed in the pores, which then has to be removed to get any sort of chatoyance back. Grain fill was epoxy, which was scraped and sanded level, finished in nitro in the typical sort of way (which includes sanding).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

No. I sanded it smooth first and turned it over and thinned it out from the back. Most planning was across grain. It has fine curl figure. I slipped up when tired.