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I have a nice stash of my favorite local hardwood that's been air drying and is now ready for further processing. It's thick and will need resawing for most purposes, including making guitar sets. So I've lately been cogitating alot on resawing and getting that game on.

Not suprisingly the OLF has been a wealth of great resawing information, especially this thead, and especially fryovanni's post towards the bottom of page 1 made lots of things gel for me. The other excellent site anyone who's interested in resawing should check out is Borson Precision Resaw. He uses a sliding table carriage to ensure straight, repeatable cuts in precious hardwoods. The sliding table concept itself is not unique, but much of his very cunning setup seems to be, and I have flagrantly stolen (or misunderstood!) the concepts for my sled from Mr. Borson. I recommend hiring his services if you have critical resawing to accomplish.

My design uses plywood and some linear guide blocks and rails from McMaster (i.e. part# 6723K12 etc.). Here is a gallery of images of my design, exported from Sketchup, and here is probably the most explanatory one:



Before I blow the cash and build this, I'm very interested in critiques from the esteemed company here at OLF

The version of the sled shown would have a ~37" stroke, sufficient for guitar parts, and cost about $300 in hardware. For an extra $100 worth of rails, one could have a ~55" stroke. This is more expensive than I would have hoped due to the linear motion components, but anything else I came up with was pretty clunky and ate much more resaw height. It is justifiable for me because I have quite a bit of resawing to do:



These are 3 1/4" thick slabs.

Thanks in advance for your input!

Peace,
Sanaka

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...imagine there were no hypothetical situations...

Really neat jig and all but honestly, I think it's overkill and I'm not that big of a fan of the indexing method (though it should still work)

I'm not a high volume re-saw guy but I've gotten very good results with a home made plywood fence that cost less than $5 in plywood (see pic). By very good, I mean that I can easily get 4 slices from a 4/4 piece of wood.

To set thickness, I usually will just cut a little kerf into a piece of some junk wood I've got around. I mostly adjust for drift by adjusting the blade on the tire until it's just about gone.

What I haven't done is make a feather board type of thing but so far, I've been successful at cutting 11" wide boards that are quite uniform in thickness. If you've got a lot of wood to process, making a spring loaded feather board would in my opinion, the best area in which to spend your time and money.

What I mean by that is some kind of spring loaded device that would maintain pressure on the boards at the top, middle and bottom of the boards to be re-sawn that you wouldn't have to re-set for each cut as the board gets thinner. I don't like the shim method of indexing because you need to make a new full set of shims for any and every thickness you're trying to saw.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I love this design. I also think the linear bearing idea is great. Can probably find one fairly cheap on craigslist or ebay. I know they are very expensive. One other think that I thought about was having the fence itself be a vacuum surface so the would be held to it by suction. The other idea I had was a second piece of equipment made from rubber coated bearing wheels and spring loaded that would hold pressure against the board being resawn in place of one's hand. If you want to work on these ideas, please be my guest. I have found little information on building a vacuum table but I might be looking in the wrong place.

I am planning on doing a lot of resawing. So I want an effective and efficient way of doing the job. Your information is great and I plan on using it.

Thanks
Ken

Sorry if anyone was reading this and the images weren't showing in my post. I forgot about one setting in the host gallery thingy and it should be good now.

Andy, if you're confident in reliable consistent results resawing 10"+ with a regular fence, I can sure see not wanting to hassle with an elaborate sliding rig! I think you'd be in a minority however. The usual problems are the board not staying flat as it gets thinner because internal stresses are released, and the irregularities of the cut compounding as you reference each new cut surface to the fence. These both necessitate rejointing every so many cuts to keep things flat. And this is probably fine in most cases, or if you're fine with 4 slices out of a 4/4 board. For really precious wood though, getting 6 slices from a 4/4 board means a whole extra instrument set and possibly hundreds of $$. And to have any assurance of that, the ideas of gluing the workpiece to a stout backer board to keep it flat and referencing the cut off a straight rail seem like a good way to go. See Borson's site where he gets 6 slices at .135" from a barely fat 1". I don't mind making bunches of shims - it's fiddly but there's only so many different thicknesses I think I'd end up resawing at.

Ken, thanks. The idea I stole from Borson about keeping the workpiece flat to the fence is to glue it to a thick, flat backer board, which is in turn fastened on to the fence with screws. So there's no need for lateral pressure to register the piece as with a regular fence. I thought about vacuuming the piece to the fence instead of gluing it to a backer board, but I'm not sure vacuum would be strong enough to keep a thick board flat that is wanting to warp from its own stresses. Plus it's a whole 'nuther system to incorporate.

Peace,
Sanaka

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...imagine there were no hypothetical situations...

Got ya on the vacuum. The gluing to the backerboard is a great idea. Now I just have to find me that cheap linear bearing out there in cyberspace.

Ken

I've done six slices with a fence a few times for clients with big bricks of BRW, but it takes a lot of effort and I'd spend a solid hour setting up my saw before each time I did it. I'll be making a sled system before I start offering sawing again. Borson has a well thought out setup; it's not the only way to do it, but it's one that's been shown to work well for someone which makes it worth imitating.

Four slices to the inch makes your wood effectively 50% more expensive, and usually anything worth resawing yourself ain't cheap. I wouldn't consider it acceptable. I do five to the inch with woods that are cheap enough that the laziness is worth the loss

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

I'm with Andy. I resaw a lot of 2" thick Mahogany and I easily get 10 slices from it using the fence that came with my Jet 18" band saw. The real key is a VERY sharp blade and like Andy said getting the drift out by adjusting the blade on the tire. I use a 1/2" 3 tpi Wood Slicer from Highland hardware and get good results. Take it at a steady pace - not too fast or too slow, either is bad - and you'll get the hang of it.

Good luck,
Chuck

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"To live a creative life, we must lose our fear of being wrong"
- Joseph Chilton Pearce

Not really Bob, have you ever priced 10" wide run of the mill curly maple from a tonewood supplier? It's much cheaper form me to find a 4/4 piece on eBay and resaw. It's cheaper to the point that going for 6 slices isn't worth the risk of having pieces too thin. I think I paid around $50 for a pice that yeilded 4 sets of reasonable quality curly.

At that price, it's simply not worth my time to get that one extra set....I suppose it depends on your volume etc.

Getting 5 pieces per inch on a 4/4 board doesn't really make any sense. If you're getting 5/" on an 2" board, sure makes sense, but if you can't get 6 out of a 4/4 piece, you may as well just do 4.

_________________
http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

Right with you Andy. No point in getting half a back...

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Alain Moisan
Former full time builder of Acoustics, Classicals and Flamencos.
(Now building just for fun!)

Another alternative would be to pay the $$ for a Driftmaster fence (Laguna) and run your wood through that by hand, after gluing your board to a backer, if you want.
It's pretty easy to cut 'on the outside of the board' with the Driftmaster. There are some videos on Youtube showing off the fence.

Cheers
John

I'm quite impressed with you guys going at this with a regular fence. Makes me realize I have more to learn and attune to about the bandsaw. So it's hard to argue about woods that are not especially expensive or hard to cut. I guess I dream about big billets of Brazilian and Ziricote. My stash of slabs is a lot harder than maple, and I guess I dream that it will be quite valuable too. The 'big' wood I'm likely to come across locally is of course Koa, where fine curly sets are running $400 these days. So I guess I'm mentally geared to the idea of maximum possible yield, where netting extra slices would pay for the sliding jig right away.

Ken if you come across the discount linear motion components, let me know! I've been looking a bit, and so far the McMaster stuff in my drawing seems pretty reasonable compared to what I've found. And its nice low profile simplifies the design.

Anyone care to chime in with problems or improvements on my sled design?

Peace,
Sanaka

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...imagine there were no hypothetical situations...

I still don't like the idea of using shims to index depth. Think about an acme screw or something like that with perhaps a cheap caliper for a DRO.

The issue is that using shims, there's no way to fine adjust for variables in your setup e.g. Blade thickness, backer board thickness, slice per inch etc.

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http://www.birkonium.com CNC Products for Luthiers
http://banduramaker.blogspot.com

I have two re-saws, one I use for spruce and the other for hardwoods. I run my stock against the fence on both saws, always. I recently processed a 10" wide 48" long piece of quilt maple for one of our members and got him full size slices that were .160 thick with a .080 veneer left over. I did make a device to hold the wood tight to the fence while sawing.

When I move my big saw into the new shop space I have linear bearings that I will rebuild my sliding table with. At present I use a sliding table only to square up billets of spruce and cedar. Once they are squared I remove the sliding table and install a fence. Works for me but I am not cutting BRW all day, but if I were I would not deviate from my system until it proved that it no longer worked. Then I would probably pony the dollars for a proper horizontal resaw which is designed for this purpose. With the current economy they are only a few thousand dollars for a decent used one...

Shane

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Canada

I too like the idea of a caliper type adjustment between cuts instead of shims. But shims seem to work for
Borson. Maybe he has different sets for various thicknesses of wood. I would be he uses the same blade brand and style for all his recutting, so various in the kerf would be minimal. And he does cut a very thin kerf.

I think the design presented here is a great one and I plan on using it. I have more wood to resaw than any one human being should be allowed to have and still getting more. On vacation this week and stopped by to purchase some great curly hard maple. It never ends.. My wife says that instead of "American Picker" I am the "American Wood Picker".

Ken

My feeling exactly. Shims are kind of conceptually perfect, but if I can devise an accurate and reasonably simple screw feed or some such, I certainly would.

Another approach I thought of would also use a sliding fence, but in the normal position left of the blade and set at the desired cut thickness. The fence would be perforated and equipped with vacuum to hold the workpiece onto itself. At the completion of cut, it would be the thin resawn piece that is stuck to the fence. Then you'd release the vacuum, remove the cut piece, then suck the remaining billet onto the fence again for the next cut. This would obviate the need to reset the fence width for each cut, and also the need to reset any featherboards/hold-ins. But this relies on each freshly sawn face staying flat enough to be suctioned on to the face of the fence (again I'm not sure vacuum is strong enough to keep a billet flat against its will as it is cut thinner). It could of course still be glued to a backer board to keep it flat. The complexity of devising the vacuum part of this, and the Borson method being known territory, is keeping me away from trying it for now.

Shane, do you think keeping everything registered and going properly is more difficult the harder the wood is? Part of what seems to drive Borson's setup is that he's routinely cutting very hard rosewoods and such. Good point that a Baker can be had cheap these days... MMmmmmm, luckily I don't have the shop space to waste time thinking about that right now!

Peace,
Sanaka

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...imagine there were no hypothetical situations...

I am not an expert on resawing to the level Borson probably is, I have only cut a few hundred hardwood sets, mostly maple, mahogany, bubinga and birch with the odd bit of everything else thrown in once in a while. I have cut also many thousands of spruce and cedar sets. I own two resaws and woodmizer (which I often use as a horizontal resaw, it is just a bit slower). My take is that some woods are indeed harder to cut than others but I think that indexing is not the issue. If your saw is set up right and the blade is up to the task it will track true and you will get a nice cut off a fence reference or from gauge block system. If your blade starts to wonder it does not matter which system you use you have problems. Both of my systems are included in threads here:

http://www.luthiersforum.com/forum/viewtopic.php?f=10101&t=27431

Kent Chasson's design is here as well.

Here is some info on my bigger saw with the sliding table:

http://www.luthiersforum.com/forum/viewtopic.php?f=10102&t=8316&hilit=+harvest

On both saws I reference off of a stationary fence to make the slices.

Again, these are just my systems that have evolved from use. There are many ways to slice wood but I try to keep it simple so I know that I am in control of the variables because if something all of a sudden is not working right (I had band the other day with too little set, it wondered like crazy) then I can quickly trouble shoot the problem, fix it and get back to work.

Hope this helps!

Shane

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Canada

Shane you are so totally Da Man. As top wood is concerned you are right up there with Steve McMinn. I managed to miss both of those threads before. Seeing your field work and your resaw process I am even more stoked about my 10 pack of Lutz tops I got a while back My resaw musings are now obviously blazing a well worn trail. As per usual I am way hypothetically overextended, and need to start cutting in order to learn a whole lot else that's useful. But I am glad to see both you and Kent Chasson using linear bearings/rails for your sliding rigs - to know I'm on a workable path with that. Your air ram hold-in is something I'll be contemplating a bit for sure - seems that sawn face to fence can indeed be a good cut reference under the right conditions Thanks!

Peace,
Sanaka

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...imagine there were no hypothetical situations...

Really, Andy. You'd have gotten 50% more sets out of that brick of curly for the same price if you'd been able to do a precise resaw; the price from a tonewood supplier is irrelevant.

Anyone who can't get five slices to an inch, also can't get three fretboard blanks to an inch. An orphan side is a lot of headplates or pickguards, and if wanted then I could also get two sets and a chunk thick enough for fretboards out of a full inch. Waste is waste.

FWIW, the sawing I've done this way was done on the stock fence that came on my Laguna so it isn't a matter of an elaborate jig if you're very careful with your setup and your method. Still, I'd say that the time to make a proper sliding jig would be saved within three resaw sessions if you've got your plans drawn up.

_________________
Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services