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I will be making a Krenov-style cabinet for my daughter’s wedding gift - so you know it has to be pretty good. She owns her own guitar repair shop (brooklynlutherie.com) and loves 20’s and 30’s instruments. Many of these were built with “fiddleback” curly maple and I will make the carcass out of it. The back will be spruce with a sunburst so you see it when you open the doors.

So I am going to attempt a coopered door in curly maple. This would be no problem to get the outside and inside radiuses correct if the wood were straight grained, but I am worried about the curly maple grain giving me hell. Does anyone have any tips for planing and scraping this wood? I know my tools need to be “sharp”.

Thanks

Ed

Ed is your daughter Mamie Minch? If so then she has a great deal of respect from me.

On planing figured woods. Yes your tools do need to be sharp, but a few things I've found to be helpful. And if you know all this then I apologize for patronizing you.

Make sure your edges have a *very* slight convex to them. This helps to prevent tearout and also will prevent leaving "tell lines" in your work. Light passes are required, dont ever try to take off a big thick shaving, figured wood tends to make you pay you go just a bit too deep with a pass.

"Trick" the grain. On the crazier pieces turning the plane to an angle other than 90' to the grain can really help. The same goes for scrapers if you have a really good sharp burr.

Other than that just make sure you never go against the grain and you'll be fine. Patience and lots of light passes and you'll be in great shape.

You can put a small bevel on what would normally the flat side of the plane iron of 10 degrees. This will increase the cutting angle presented to the work from 45 degrees with a standard flat back iron to 55 degrees with a back beveled iron. This mimics a high angle plane and will reduce tear out. The back bevel can be very small 1/32" or so. What a wonderful gift!

_________________
Jim Watts
http://jameswattsguitars.com

Set the chip breaker very close to the edge of the blade. You won't be able to do that if you do the back bevel though. Going more across the grain certainly helps.

Ed, As mentioned elsewhere (where it's hard to post pictures), I usually deal with highly figured wood with a high angle plane, if I'm looking for a finish. In the pic below, I've just moved from a standard angle plane (45 degree cutting angle) to a high angle plane (60 degree cutting angle). You can see some tear-out on the panel left by the standard angle plane and the continuous fine shavings ( = no tear-out) as I finish with a high angle plane.



This next pic shows the result of cross planing ribbon grain EIR. A standard angle plane is pushed at 90 degrees to the grain. You can get rid of wood quickly by doing this, without tear-out, but you don't get a nice finish. So you have to move to a scraper, a high angle plane or a ROS. For me, the high angle plane used in line with the grain gives the best results.



The final pic shows the finish left on figured wood by a high angle (60 degree) plane. It's about as good a finish as you can get irrespective of technique. The pic was taken to avoid reflections, but this is a pretty glossy finish (think finely planed spruce).



My weapon of choice is a modified #6 (frog tilted to 60 degrees) shown below with a standard angle #3 in the foreground to compare the frog angles.



Probably the easiest way to get into high angle planes is to use a high bevel angle (40 degrees) blade in a standard bed angle (20 degree) bevel up block plane. To be worth doing, you need at least 60 degree cutting angle. To work well, you still need all the other stuff going on; well tuned plane, super sharp blade, crescent edge, finely set etc. etc.

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

http://www.goreguitars.com.au

Hi Trevor,
How did you modify the #6 to make it a high angle - put a shim under the frog?

Thanks all

Lots of good information with the only common thread being "sharp". Yes Trevor, how did you alter that plane?? Lie-Nielson offers a range for their planes:

https://www.lie-nielsen.com/nodes/4132/high-angle-frogs

The interior of the curved door will be more difficult than the exterior because of the concavity. Below is the assortment of tools that I have that I will try-

Upper left is a flea market cherry smoother that I radiused front-to-back and side-to-side for chair seats - it has a nice double iron and works like a scrub, so I will have to play with the blade a bit. Upper right is a travisher, a curved spokeshave that is good for hollowing, and I have used it on some knotty wood with good success. Bottom right is another fleamarket find, a thick scraper blade that was already radiused on the right side, too thick to bend. It is a Stanley made for the 12-series of scraper planes, I think, and they are sharpened with a 45° angle on the cutting edge. I have used it with and without a hook with success. Bottom left is a Stanley 20° block plane with a blade sharpened at 45° for a 65° cutting angle. I have used it for chamfering edges with success.

Of course there is always electrickery. I could hang a router from a pivot and do the interior arc much like the fretboard radiusing jigs I have seen.

Thanks all for the input. I recently bought a used thickness sander and look forward to giving it a workout on this piece.

Ed

Violin makers tend to work cross grain on the arches on the back, whether planing or scraping. The plane is toothed, and used primarily as a roughing tool.

A lot of wood removal is done with the scraper, and this is where a heavy scraper really shines. I learned about these from Carleen Hutchins, who picked up the idea from Saconni, who said that this was the type of scraper that Strad used. My favorite one is about 1/10" thick, made of M-2 tool steel that is fully hard. The surfaces have been lapped flat and the edges are ground to a 90 degree angle. The burr from grinding is the cutting edge: with steel this hard you can't turn a burr. One of my students has been making these and selling them through the usual outlets. The thick metal doesn't heat up the way a thinner card scraper does, and the hard steel holds an edge longer. You can also use these one-handed: you sure can't spring them!

You can also put a very short bevel on a normal block plane iron to get close to a 90 degree cutting angle, and use it as a scraper plane.

If you look at the pics of the planes, you'll see how I drilled straight through the cheeks of the #6 plane and inserted a round bar which sits exactly on top of the frog seating. The frog bolts down on top of the bar to its original hole locations, drilled out and re-tapped for larger, longer bolts. I used M8 socket head cap screws. (I've never been able to figure out the thread sizes on Stanley/Bailey planes).

The flat bar with the couple of screws you can just see under the frog are stop screws to help set up the frog and get it square. The flat bar is bolted to the plane body where the standard frog adjuster normally goes. I used a Lie Nielson aftermarket blade which was so thick that the blade adjuster wouldn't reach through to the cap iron, so there was a mod required there, not required if you use a blade closer to standard thickness.

The bench planes I use mainly are 5, 5 1/2, 6, and 7. I also have a 3 and 4 1/2 which get virtually no use. All except the 3 and 5 use the same size blade, which can be sharpened to the same bevel angle, so they are interchangeable, which can be handy. I bought the #5 when I was 21, (a couple of years ago!) the #7 was a gift and the rest are flea market.

Regarding the lower angle high angle frogs (50 degrees, 55 degrees) on the figured woods I tend to work those angles don't seem to make much difference. In my experience it all seems to happen between 60 and 65 degrees. Above that you move rapidly into scraper plane territory.

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

http://www.goreguitars.com.au

Thanks Trevor - clever with the plane.

Ed