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Router/Planer in Use
In this case some case-hardened cocobolo slices. After sawing these last year they cupped badly on the outer slices of the 1" boards. Inner cuts weren't bad at all. You really don't want kiln-dried planks for luthierie, air-dried is preferable to eliminate or minimize case-hardening.

So, I've learned to relieve this case-hardening by attacking the outer part of those planks. Another thing is to add moisture to the inner side, allowing it to swell these pieces toward flat. Yes, wet only the concave portion, leave the other side dry.

Enter the Router/Planer, it is relieving this case hardened wood off the opposite side of the bookmatch. Keep the bookmatch at all costs, plane the opposite side only. Well, it's work, what can I say. But this beautiful and, otherwise, worthless to the luthier wood, can be reclaimed.

That said, suppliers of quality flat tonewoods are to be applauded, especially in the more dense and resinous hardwoods similar to Cocobolo or really oily Indian Rosewoods. Could you do this with one of those really small planers, of course. I'm just not sure of how thin it could go.

I took this stuff down to .150 / .170 and then headed to the drum sander. You guessed it, it crapped up the belts and ruined them. But I used to crap up way more than one set. I'm happy with my little Router Planer. And I would like to add one more thing, "Beat Ya, John K." I took about .050 to .070" off in a pass.

Great job Bruce, looks really nice! How bad was the wood cupped before you started? How much wood did you try and take off in the drum sander in a single pass?

Cheers!

John

Nice looking clapboards you got there Bruce. Just seems like a lot of work...

Terry, wait until you see this wood in the set. Looks like Brazilian, but one whiff of this strong cinnamon toxic stench and you'll know it's cocobolo.

A lot of work, but recovering wood I already bought and paid for. This was cut before coming up with my current thrust bearing setup on my big bandsaw. Now it's a snap. You'd still have trouble with these old boards though. No telling how old they were either.

It was cupped and thick and would not pass through the 1/2 inch opening of the router setup. So I took it to the bandsaw starting off for a couple relieving passes. So the router helped two ways, slowly relieving the crown of the cupped side, then by dampening the concave side, the wood relieved from swelling of the other side.

Having dealt with a lot of cupped case-hardened maple, I knew what to do. It works, but you have to be patient and allow the moisture to do it's part. Old-timers may laugh, but when you see it working right before your eyes, it's convincing. Of course when you finish, wisdom says sticker and weight until dry.

so this could be used for thicknessing plates? or woud it be too rough?
I am expecting a wagner saftey planer soon and have no access to a thickness sander.

[QUOTE=Dickey] Terry, wait until you see this wood in the set. Looks like Brazilian, but one whiff of this strong cinnamon toxic stench and you'll know it's cocobolo.

[/QUOTE]

YUMMY! Can't wait to see the pix! This fall or winter?

BTW wouldn't it look nice as an upgrade to vinyl siding? Terry Stowell38583.9338888889

Jag... yes, with a little additional scraper work, or Dual Action ROS, Random Orbital Sander, I think you could. John Kinnaird brought this up again after seeing an article on John Greven making 40 guitars a year with few jigs or big tools like a drum sander.

My main purpose was to remove excessive resinous wood which normally ends up ruining abrasives. A small planer would probably work too for 3 to 4 hundred bucks.

I think I spent about twenty bucks. $20

This router has multiple duties in my shop, it cuts my 5/16" notch x-braces, routes off top and back overhangs on guitar bodies, and other general duties.

matter of fact, with a carbide blade now on my big bandsaw, I get smoother wood right off the saw. So this tool isn't for everyone, but I needed it to help with cocobolo crud on my belts. I love cocobolo except for two things, allergic reactions to skin and respiratory, and crudding up abrasive belts.

Stowell, you build a house out of this and you'd never go inside. You'd just stand out in the yard and say, "Hey, What do you think of my Cocobolo House? Purty ain't it?" Yep, that is one pretty house Stow, one pretty house.Dickey38584.0076041667

John, on the drum sander I usually just barely get it to cutting and send it through at an angle.

By sending it on a bias, the drum tends to sand better, straight on, well it gets hot and resin melds with dust and quickly coats over spots of the drum abrasive.

I don't really know how much I remove in one pass. But I move the adjustment between two and three inches, which equates to ten to 20 thousands in a pass, somewhere in that neighborhood.

I've never sanded cocobolo without gunking up abrasive, so it has to be computed into the cost of the guitar.

there is one noted builder who uses a similar set up to thichness his plates.

   I like that little device. Makes for a fast job on small stuff. I bet you make lots of sawdust. I hate the saftey planer and your method looks much safer.
John Hall

John, I was worried it might climb up off the wood, but the weight of your hand and the router, well it's just right for control and cutting pressure.

The other problem is repositioning the workpiece each 3/4 inch pass. Turns out, by putting torque on the board with your hand and sliding it into the base, contact between board and base is good. Not perfect but good.

I didn't ruin any wood, the twirling router bit tends to push down too as it cuts, helping maintain base contact with the wood. Hold downs would be a plus, especially the type that roll, putting downward pressure but no forward resistance when feeding the wood in. Nice little tool.

I thought longer approach and exits would be great, but would eliminate the ability to torque the wood flat and tight. So with long feed hold downs would be needed.

Check out this image from a guy on MIMF (that's not a dirty word is it?) Anyway, he had fun with my jig by posting this. I thought it was funny.

Dickey38584.5760185185

Hi Bruce & everybody,

In an earlier discussion about this Greven-like solution to thicknessing, I promised you some pics of my hacked-together router thicknessing jig. It's very similar to what you came up with, with a few useful mods.







I used flexible sheet polyurethane as hold-downs in both the intake & outfeed sides. On the intake side, the long solid blue poly hold-down is adjustable up & down approx. 3/16". The out-feed hold-downs (smaller blue poly pieces) are set at approx. 1/16" tall. Since this jig is for thicknessing tops, sides, & backs, the poly outfeed hold-downs are flexible enough to let me push the thicknessed wood through while keeping said wood snug to the backboard. And, of course, one would set the infeed hold-down to the thickness of your raw plate.

One big limitation is that the aluminum tracks are only 1/4" off the backboard. For acoustic guitar plates this is fine but somewhat limiting for electric guitar bodies, etc. Also since the router slides along the aluminum channel, it helps to add a little lubrication.

I made this thing with a routable width of 19" so that I could thickness joined plates.

I hope all that's clear and understandable.

SkipSkip Beach38585.3952430556

HEy Skip, that thing looks nice and simple. Nothing wrong with that. Mine only goes up to 1/2 inch, and it would be nice if it went up to say 1 1/2" for thinning two by fours and such. I guess a quick bolt change on mine and varied thickness of support stock and it could fit a lot of needs. Good job, thanks for sharing, looks like you used the same aluminum angle I did for mine.

hey, you got any of that flexible stuff left? I don't need much, that might just be the ticket.

Hey Bruce,

That blue flexible plastic stuff was cut from a cheap plastic storage bin top ... you know, the ones in KMART or Walmart for $7. I threw away the remaining pieces, sorry. It really does help to have some sort of hold-down scheme, though.

Skip

You are kidding, you threw something away! Okay, that makes sense, I bet I have something that will work with just a bit of tension that's plastic.... hmmm, I saw a couple plastic spatulas at the dollar store....

I hate that. But I really like your sliding solution. The rollers are just a cool idea. I am going to go for wheels on my hold down, so what do you think of that.

Anyway, cool work to both of you guys who have pics here. Looks like very precise work.

Bruce, if you just took that on down to about .125 inches and then used a scraper to get the little lines out you could save ruining any paper.   Just another thought.

John

Disqusting note. I took those really close boards over to the drum sander, well.... successfully crapped up both drum abrasives, then, pop, slap slap slap........... both came off and wrapped all up ruining both sets. Bummer.

I can sand Mahogany, Sapele, Spruce, Redwood, Zebrawood, Red Cedar, and others and the paper lasts forever. Slap a set of cocobolo on there and it's doomed, even with the router planer. Okay, I get it, no more coco in the drum sander.