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Hello,
I was wondering if anyone could share a surefire technique for keeping the back of the neck flat while carving. For instance, the shoeshine works for making it nice and rounded, is there a corresponding technique to getting it flat? Currently I shape the first fret curve, the 10th fret curve, and then join the two planes as best I can with a spokeshave. But I still find I need to flatten out little dips and grooves with a sanding block afterwards.
Any tips?
Thanks

I simply get it close, then do the shoe shine with a 6 inch wide piece of 80 grit cloth backed sanding belt - it does the rest . The cross grain action looks dofferent than the lenghtwise shaped marks left by reasping/spokeshaving, and it will be flat between the nut and 10/11th fret ...

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

I'm assuming you are talking about a guitar. Several suggestions here, rather than itemize I'll just mention the process I use:
- thickness the neck to the proper measurements at the 1st and 10th keeping the profile still rectangular and the flat of the back parallel to the FB
- draw a center line down the flat of the back
- use a farrier's rasp or other preferred tool to shape the sides till they are almost to the FB keeping them square to the flat of the back.
- measure up on the sides 1/8" above the FB and draw a line. Now measure 1/2 the remaining thickness on the sides and draw that line. Finally on the flat of the back mark 1/2 the width on each side of center line and draw those lines. These lines will tape from the 10th to the 1st.
- use a spokeshave, or better yet a farrier's rasp, and remove the wood between the 1/2-way lines keeping the surface flat. Check with a 6" steel rule as you go. This is where the big flat non-tapered farrier's rasp really shines.
- now got back and draw new 1/2-way lines on the new flats
- using your tool again take off the peaks to make even smaller flats.

you get the idea, you just keep making progressively smaller flats till you end up with a rough round. But the process keeps the 1st -> 10th areas nice and even. You can see this process on my web pages
http://dunwellguitar.com/
Click on the Luthier's Pages button and go to the Let's Build A Guitar and page 8. I kind of skipped over the step of rasping off the sides of the neck but you can see the result in the first photo.

FWIW,
Alan D.

I use a Wagner Safe-T-Planer. It's quick and accurate.

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Ken Franklin
clumsy yet persistent
https://www.kenfranklinukulele.com

Yeah, I use the wagner safety planer too to get the thickness within about 1/2mm of final between first fret and heel then I have that as a datum which just needs to be rounded over leaving the centre untouched except for final sanding.

I start with the Saf-T-Planer, as mentioned. I drawn marks across the centerline of the back. I make a cross section gauge for the first and tenth fret positions, and I gradually work the neck down with shaves and rasps to just a little thicker than those profiles. As the neck acquires roundness, I always leave a narrow remnant of my reference marks all down the center of the back
(no wood removed there). When I'm close to where I want to be, I switch to a long sanding block, held parallel to the neck, but rubbed perpendicular to the neck. This block is just a bit shorter than the desired flat length of the neck back. This smooths out the facets left by the shave or the rasp and file marks. Then you can use the shoe shine method, blend in the head stock flare and the heel, and final sand with the grain. And it goes without saying that I constantly check my progress with my cross section gauge.

Let me clarify...
I start out with the old safety planer first as well (so so much better than the edge sander drum that I used to use)...
So the neck is tapered appropriately for thickness at the nut and heel end. Then I carve the curvature at the 1st and 10th frets and try to join them. However, the spokeshave doesn't necessarily carve in a dead straight plane, so there are usually little dips that need to be sanded flat. Maybe I'll try a wider piece of paper for the shoeshine step...

Though the long flat sanding block across the grain is how I usually resort to getting rid of the dips as well, I wonder if there's an 'aha' for flat like the shoeshine is for roundness...

Are you using a flat bottom or a rounded bottom spokeshave? The flat sole works better for keeping the profile straight. The rounded one works better for carving things like Queen Anne legs. The little dips are most likely being caused by not keeping the sole of the spokeshave perfectly parallel to the work, ie you are most likely slightly rotating the spokeshave front to back while drawing it causing it to take an uneven cut. A good way to gauge how even your cut is while shaving is to watch the width of the shaving coming out of the tool. If it is a nice even width you are taking a nice straight, even depth cut. If the width varies you are taking a deeper cut when the shaving is getting wider and causing a dip or valley. Concentrate on nice steady, even pulls from start to finish. This combined with the quadranting already mentioned should get you better results.

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Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

What about using a block plane instead of a spokeshave?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

small spokeshave (lee valley, chinese spokeshave) to join the 1st and 10th fret profiles works best for me. AND I always use a short(8" , flat cork-face sanding block with 80 grit paper prior to any 'shoe-shine' action to eliminate any bumps and/or dips. I find that even if your spokeshave skills are very good, any slight variation in the density of the wood can induce a dip or bump. This is less of a problem with spanish cedar, but often a risk with mahogany. Just take you time.

The length of the sole will most likely be a problem , a spokeshave was designed with this type of work in mind.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/

Actually Robert's video said to use a block plane because it helps in keeping the carvings straight. He said with a spokeshave you risk carving a concave into the neck. I used it and the size isn't a problem.

_________________
Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Me keep a beaver under me work bench.
every so often me throw him a neck and say,
Here chew this.

He does a pretty good job now that I got him trained.



blessings
Padma

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Audiences and dispensations on Thursdays ~ by appointment only.


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There are smaller block planes. One of my favorites is a Stanley #101. The older cast iron ones, not the sheet metal version.
Here are my two favorite planes....a #3 'no name' on top, and a Stanley 101 on the bottom.

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John

I tried my little LV green squirrel tail and that worked well too. As well as my handy Boone planes...
Still found myself sanding with a flat block. Certainly not the end of the world but somewhat time consuming...

yes that is true, but with practice, patience you will develop a feel for the proper use of a spokeshave. Even a small plane like the 101 has a sole 3.5 in long, so your starting and ending profiles must be long enough to seat the sole or you will not lead in or finish straight anyway. You also run the risk of the plane running off and the nose making small dents in the heel or hyoid curves of the head depending which direction you need to cut. I prefer a spokeshave for these tasks, but if I was to use a plane I would most likely pick up my #90 bull-nose. In the end though you should find the technique that works best for you.

_________________
Brian

You never know what you are capable of until you actually try.

https://www.howardguitarsdelaware.com/