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A significant portion of my work is carving archtop plates, and strangely, this has led me away from a mechanized approach, like a duplicarver or CNC setup. Since i spend a good portion of my time doing this, i want that time to be enjoyable, and standing in front of a duplicarver or programing and running a CNC machine are not my ideas of a day well spent. Instead i have developed a carving routine that is fast and efficient, and leads to a nicely shaped arch without spending a lot of time "correcting" lumpy archings. I am demonstrating with a mandolin top, but the process is the same for archtop guitars, les paul style solidbodies, violins, or whatever.

The first thing i do is adjust my purfling cutter for a cut that is a little bit thicker than my final edge thickness
And use it to mark the edge thickness around the perimeter of the plate, you could just mark it with a pencil also.
Next i take a plane, a scrub plane would be perfect but almost anything will do, and facet the plate, so that it is sort of pyramid shaped, this gets rid of a lot of the waste and starts to establish the long arch
I then quickly and aggressively carve down the edge with a large gouge, carving across the grain starting at the edge and carving towards the middle. I am not really worried about the shape of the arch at this point, i just want to get the edge down so that the safety planer used in the next step does not need to work too hard.
Next is the classic safety planer trick we all learned from Bennedetto

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Jordan Aceto
Ithaca, NY

After the edge thickness has been established with the safety planer, i switch to a flat plane, a stanley 100 1/2 or similar works well, and use it across the grain to establish the long arch, so that when looking from the side there is a nice gracefull arch from neckblock to tailblock
Then i switch to finger planes, the 12mm ibex is my favorite, and start to actually work on the arch proper. I use lots of strokes starting in the middle of the plate and radiating downhill, working in this way helps to avoid puffy archings.
Then a quick scraping so that i can better see what still needs work, i look for lumps, hollows and uneven archings at this point
Adjust as neccesary, and clean up with a scraper and sandpaper.

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Jordan Aceto
Ithaca, NY

Amazingly helpful!

Now what do we do on the other side? I have been wanting to make an archtop....and have no clue...

Stephen

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www.ziegenfussguitars.com

Now for the "other side"

I start by removing the bulk of the waste with the gouge again, carving crossgrain, using mostly long strokes from one side of the plate to the other
I then setup a depth stop on the drill press, like Bennedetto shows, and drill a series of holes so that when i carve to the botom of the holes, i will have an even thickness that is skightly thicker than my final desired thickness. I use drill bits to set the depth
I like to carve the bulk of the waste away before drilling, because i find it harder to carve with all those little holes, the plane or gouge kind of jumps and stutters through them. If there is not too much to remove after drilling, its a piece of cake to carve untill the holes just dissapear
At this stage, while the top is still a little bit thicker than it will end up, i cut the soundholes, which will be the next installment.

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Jordan Aceto
Ithaca, NY

Great post, Jordan! How refreshing to see some no nonsense hand tool work (well, mostly) for a change. It seems more and more people are moving to more mechanized methods for plate carving.

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Rian Gitar og Mandolin

Good stuff Jorden (outside pics a bit dark though). To my mind, this is the way it SHOULD be done, at least at first, 'till a builder gets a feel for what's happening. It's interesting to note that the "drilling the inside" method (although without the stop pin) goes back several hundred years to early violin construction (ie drill down with a spoon bit & keep measuring 'till it's the right thickness, then do another.......yes Mr Stradivarious)

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Dave
Milton, ON

They are a little dark, sorry.

I have been thinking about making one of these http://www.darntonviolins.com/images/gradchopper.gif
its a graduation punch like the old school (old testament?) guys used to use.

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Jordan Aceto
Ithaca, NY

Nice to see the use of hand tools!

Here is my puncher. They work very well. I make double basses so I need a big one.

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Ken

Thanks for the technique, I'll be sure to try it on my first LP.
What is a desirable thickness at center?
If you had a .25" edge would you want a .25" thickness at center?

Really great tuto !!! Thanks Jordan

I like to work with hand tools, you have time to see a mistake's comming...

I enjoy a lot hand carving the top of my second electric guitar... so quiet and peaceful...

Thank you very much for sharing, I look forward to learning here at OLF

When cutting the soundholes, you can just use a knife and files/sandpaper sticks if you want to stay amish. If you are doing more than a few of them though, it is nice to plug in.

I use my binding machine, which is a modified polaroid land camera, as a mini pin router.
I just clamp a piece of scrap mdf or plywood to the base, chuck a 1/4" or 1/8" bit in to the router, and plunge a hole into the scrap table, then i press a 1/4" or 1/8" steel pin into the hole i have just made.

I then clamp the top to a template like this
this one is setup to do either oval or F holes in A or F style mandolins, the guitar rig is the same, just bigger.

If my top blank is long enough, i leave tabs at the neck and butt ends, which are drilled to accept the bolts sticking up out of the jig. This mando blank was on the small side, so i just cranked on it with over sized washers, hopefully the picture will be self explanetory. Basically, any way you can secure the top to the pattern will work fine.

Then i just plunge through the top and cut away, riding the pin on the pattern to give me the desired shape. Notice the high tech depth stop in the first picture (it's a C clamp)

That all! Notice that the top is still quite thick at this point, now that the hole is cut i can start to graduate the plate down to its final thickness, and add any binding/purfling to the hole.

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Jordan Aceto
Ithaca, NY