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I've had a quarter of a spruce log for about 10 years, it's well aged and stable. I've been waiting for the right occasion to cut it up, and it just so happens that I'm building an archtop. The wood would be perfect for that, I figure I can get at least two violins out of it as well..

The rub is I've never cut something that large, my bandsaw will do it, but I'm not sure how to approach it.

Any advice?

Thanks
-Paul-

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-Paul-

Patriot Guitars

I get my spruce in hand split wedges about 3"+ across the inside, and double that + on the outside. I'm sure there's vids somewhere on the process to split logs.

I joint one section of the wedge on the outside (bark), towards one of the faces, then start resawing. When it starts to go ever so slightly off quarter, I do the same to the other side and work my way in. If I were doing an archtop, I'd see if I could split off enough so that one cut down the middle would make my two sides.

By the way, the first cut off the split face could be considered waste, but I cut it wide enough to make brace material. Depending on how big the face of your log is, you may be able to take a chunk out of the "inside" of the log for brace material, which also gives you a flat "top cutting surface" so your saw can be adjusted to one height effectively.

What are you using to split it?, I'll post a picture of it tonight. I'm wondering if I wax up a large and old sharp saw I have (it was my grandfathers), if I could use that and a wedge to cut it down the middle...

Thank You...
-Paul-

_________________
-Paul-

Patriot Guitars

I cut billets radially. It's a simple ratio between the inside width and outside width. Put a tall fence on the band saw and tilt the table until you get the right dimensions. I have an appliance on my planer that allows me to joint pieces up to 12" wide so I can start with an absolutely flat side but it could be done with careful hand planing. The other option is to make a tilting fence or you could make a one-off fence out of scrap that's tilted to the correct angle. There are many options but radial cutting guarantees perfectly quartered tops.

Can I come over...



I'll work on it tonight, but it makes me nervous, it's just about perfect at this age

Thank You

_________________
-Paul-

Patriot Guitars

The first few cuts on a large billet can definitely test your arm strength .

Sorry for the confusion, my billets come in already split, so I can radial cut it like John.

Also, as John mentioned, the basic process would be to bandsaw the 1/4 down, either by making a sled, or jointing a flat edge.
I mention splitting it for a couple of reasons:
-easier to resaw a smaller piece
-your instrument will be built with a hand split spruce top

Just a different means to the same end.

Please post pics of the process, if you can. Having trouble imagining a pie shaped wedge on a bandsaw.

Thanks!

The next billets I'm cutting (Red Cedar) are out of a tree so huge I just squared them off. No need for radial cutting so photos would be a waste of time.

Err ... wrong.

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George :-)

Get yourself a musclebound helper.


Split into pie sections w/wedges.


power plane off the bark and create flat side.



plane straight edge on bark side for fence.


Tilt bandsaw to keep rings on quarter and make sure you have a surly expression while you cut!

If you're going to store the billets for any length of time make sure to remove the bark and a layer of wood just below it. That's where the boring beetles lay their eggs. I lost a small stack of Engelmann spruce once when I neglected to do this.

Good advice on removing the bark, but note that will promote cracks on that surface. Sealing will help prevent cracks, but sealing in the moisture will promote blue staining in the sapwood, particularly in the summer. For those reasons, it is best to cut the wood and dry it as soon as possible.
The illustration of the sawing is similar to my method. I flatten the bark surface on the jointer, or by sawing on the bandsaw. The first cut is through the middle, guided by the flattened edge of the split surface at the bark. This assures no runout at the bark edge of the tops, which is normally the edge that is joined.
You can saw 3/16" guitar tops, or saw 1" boards that can be resawn into four slices once dried. Sawing 1" boards is faster. This is particularly important if time is short. You must work faster in the summer, because that is when borers and blue stain are most active.
3/16" guitar tops are placed on 1/4" dry sticks and a box fan is placed on the stack. The tops will be dry enough to prevent staining in 2 or 3 days. 1" boards take longer....over a month, usually.

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John

Perhaps the biggest benefit of going from tree to guitar top at least once is you are unlikely to ever feel topwood is overpriced from a supplier. The energy required is astounding.





Cutting parallel to the split where the center join will be is especially important with the Engleman growing (and mostly dying )around here. It tends to grow with the grain wrapping like a barber pole.

It was from your post and pictures at UMGF that I learned this important detail. Thanks again John Arnold

We used to make semi-annual trips to the Bitter Root Mts. in Montana to harvest Engelmann. I would take days to find the right tree since it had to be damaged in some way (leaning, lightning strike, etc.) and not a "twister". I would guess only about 1 in 20 Engelmann trees grow straight probably fewer. Nowadays I'm much too old to be packing billets up and down mountain slopes to get back to the pickup but I always looked forward to the trip. The scenery and wildlife was amazing!