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I'm pretty good with my hand-planes and want to thickness with them. In the past I've hand planed my mandolin sides and had a lot of trouble holding them during the process. I clamped them at one end and swapped the clamp as I planed. With these much larger pieces of wood, what's the best way to keep them still?

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Hutch

Get the heck off the couch and go build a guitar!!!!

Thicknessing is totally doable with handplanes. If you're using western style planes for this job I'd suggest a #5 size. Start with a cross grain cut and then transistion to a diagonal cross grain cut. Once it's down to about 1/32" from the thickness you want I'd transition to scrapers for the final few passes. This will take off the plane marks and give you alot better control over the final product. A light set on the cut and *sharp* blades help reduce tearout alot, especially on the cross grain cuts.

As for work holding, bench dogs are really the most accurate and fast way to plane wide thin boards. If you don't have a setup like this and you're going to do lots of sides I would highly suggest investing the time and effort.

Look up carving benches for some other ideas.

I have all of that, I guess I just need to try it on some scrap. Thank you

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Hutch

Get the heck off the couch and go build a guitar!!!!

Some people use a bench hook with a stop about the same thickness as the finished panel will end up.

Tape and CA glue work, too......tape to bench, CA on tape, tape to bottom of work, mate, plane. I use two or three. Peel tapes apart, done. Not my idea, but have used it with success.....

Or just use double stick tape?

That's what I've done in the past and it seems to work fine. I don't like having to move dogs and or being careful not to hit them and a back stop of .09in is a bit too small to hold it down.

What kind/brand of double stick tape? Can I get it in wide rolls?

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Hutch

Get the heck off the couch and go build a guitar!!!!

OK I found some 1 1/2" XFasten removable no residue tape. It even states "used by luthiers". Sounds perfect.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I just get 3M double stick tape at my local hardware. I'd be careful using the wide stuff because some of it is so strong you might have difficulty removing it. Though that says removable so I don't know.

If using double stick, get the thin stuff....otherwise wood bends using the foamy stuff. I started with foamy double stick and then evolved to masking tape/CA......

It's easy to use too much double stick tape and make it hard to pick up your piece. One piece of tape at the tail end of the plate would do it. Also, get yourself a Stanley 80 (or equivalent) scraper holder. Makes quick work of final scraping

Ed

Thin stock - particularly sides being thinned to 0.085" or less - will buckle if placed in compression during planing...such as when dogged to the bench. Keeping sides in tension works better, and can be accomplished with the already mentioned double stick tape or using a holdfast at the near end to lock it in place. As mentioned, scrapers are useful and there are few things in luthiery that are as much fun as peeling off long, thin scraper shavings from a Brazilian rosewood side or plate...smells like double chocolate brownies made with Dutched chocolate baking!

For tops and backs, which typically run over 1/8" for top 'rosetting' thickness and closer to 3/32"" for backs, as well as being 10" or so shorter than a side, buckling is much less of an issue, and box nails or keeper strips on a carrier board dogged into the bench can do the job, as well as double stick tape. Mr. Cumpiano has a decent treatment of hand planed prep of sides, back, and top that is worth reviewing, although he does not get in too deeply with regard to technique.

Finally, the thing that makes the most difference for me in the outcome from my little Stanley #3 (thanks again, Mr. Minch!) or my cabinet scraper is starting with a very sharp blade.

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For the times they are a changin'

- Bob Dylan

I've been using Scotch 3M removable poster tape (3/4" wide double stick tape) for years for many things. It works really well and it is best used sparingly, particularly with thin pieces like sides if you don't want to risk breaking them when unsticking them. It can be bought singly or in multi-packs.

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Once in a while you get shown the light in the strangest of places if you look at it right - Robert Hunter

The trick of masking tape and CA glue is better than double-sided tape in my experience. It holds better, is more easily removed, is flatter, and cheaper. If you haven’t tried it yet, google the you-tube video by Ben from Crimson Guitars in the UK, which demonstrates it quite nicely. This will change your life for the better!
Here is the link:
https://m.youtube.com/watch?v=ub6PsY4cgwg

Keep in mind that on thin, flexible stock such as mahogany, maple, walnut, and ash sides, double-stick tape or tape + CA will result in some reduction in stock thickness where the tape is used, as the plane will produce a flat surface despite what is in that area an uneven substrate. Plan on losing up to 0.004" for double-stick and up to 0.010" with masking tape + CA (twice the tape thickness plus 0.0005-0.001" for the glue).

Here are the thicknesses of common shop tapes used for temporary fastening:

Scotch brand Blue Painter's Tape: 0.0085"-0.009" (2x 0.004" plus glue line thickness)
Scotch brand Delicate Surfaces: 0.0065" - 0.007" (2x 0.003" plus...)
Fasten brand double-stick: 0.003"
Shurtape brand fiberglass scrim double-stick: 0.003"

Double-stick tackiness and holding power can be controlled with fine wood dust, making the usual adjustment and re-positioning of stock a little less fraught in terms of risking cracks or splits. Naphtha provides a near instant release for fiberglass and some paper-scrimmed double-stick tapes, and is very handy when working more split-prone stock. We also use it on the 1/64" aircraft plywood backers we use on some rosettes to guarantee an easy release after milling.

On box nails - they are set into the carrier board so that the head is below the desired final thickness of the stock to be works...one trick is to use a bit of steel 0.015" shim stock under the head of the nail towards the work...this leaves a nice gap between the carrier board and cocks the head a bit to better engage the stock. We have a few bits of stray bending slat that do nicely for the job.

If your box nails have an especially thick head on them, or simply too dull to hold the work, a quick touch on a belt or disk sander will thin and sharpen.

_________________
For the times they are a changin'

- Bob Dylan

I clamp a 20in L mdf 1 by 3 across the back an sides on a large cabinetmakers workbench , and do 1/2 of each side and then rotate. For the sides I copied a jig off youtube that sits in a shoulder vise its a 1 by 6 by 36 in ply board with a block of wood with sandpaper backing underneath at 1 end an 2 de staco flip clamps that lock down the side, so that I can use a LV cabinet scraper or number 80 scraper to smooth the sides in preperation for bending or laminating the sides. The youtube video luthiers name I forgot ?? but it was a younger man with a spanish surname , it was a great video for those who want to prep their T,B and S using hand tools only .!

Another method not yet mentioned is to tack the stock to a carrier board with hot melt glue (just run a few small beads along the edges). By knowing the thickness of the carrier board you can determine the thickness of the work piece (total thickness - carrier board = stock thickness). The hot melt glue can be released with denatured alcohol after the final thickness is achieved.

So many ways to do this that I didn't think of. Now I wish I hadn't ordered the double sided stick tape.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

Double stick is broadly useful for everything from rosette milling and assembly to holding bridges for shaping...the tape and CA trick is used occasionally here, but the rolls of double stick get used far more frequently, probably as much because of all the template work we do as for actual on-guitar work.

_________________
For the times they are a changin'

- Bob Dylan

That sounds like a lot of scraping!

I originally learned to drill a small hole in each corner of the plate and tap in a little Brad and secure it to the work board so that the head is below the target thickness. The plate, and Brad, come up quite easily with a chisel pry.

I've also used the clamp method (remember on thin sides, always plane away from the clamp. DAMHIKT) and shop made perimeter dogs of sorts. Lately I have made a lot of om, so I made this vacuum jig. It works great.

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Pat

Yup, if you have a good strong 112 or other variety of scraper plane it goes fairly quick. A nicely burnished blade helps alot as well

And the beat goes on. It's incredible how many different methods are used to accomplish the same thing. I posted this on 3 different forums and got valuable info from all three. I think one of the most interesting is hot glue. I've got to try it.

_________________
Hutch

Get the heck off the couch and go build a guitar!!!!

I might use a scraper for the last few thousands. But 1/32" is like 20 to 30 passes with a plane taking off 1 or 2 thou per pass. How thick of shavings are you getting with a scraper?

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Pat

I haven't measured them. My 112 gets pretty thick ones with a VERY lightly cambered blade, I use it for leveling out softwood like pine. I honestly prefer my japanese planes for dimensioning anything thin these days. Especially handy for things like patches and cleats.

Setting the cap iron to have full influence is the ultimate solution for tearout free planing.
Look up David Weaver or David W on youtube, as he has done the most work on putting this information out there.
It is a night and day revelation when you learn to use the double iron.
No tight mouth needed, so frog set all the way back flush with the casting, or the plane won't work.
Here's the link
https://www.youtube.com/watch?v=9pAVgfSPMN0

Tomas