Spalted Maple top...several questions

[Dr Ron]

Hi,

I have a mahogany ESP Body and I bought a Spalted Ambrosia Maple book matched  top 3/8" rough sawed.

I loved the look of the wood, only now am I realizing that I bought one of the most difficult woods to work with (figures).

 

Okay I know the wood is decomposing wood. I have a few questions:

1) The pesky arm contour...First of all do I apply the Minwax wood hardened before I bend the wood? My plan for bending is to rout slots in the back, and use an iron for the glue up.

2) Should I use Minwax Wood Hardener, or epoxy? I saw a video where a guy poured epoxy on the top and spread it around then used a blow torch to rid of bubbles and the milky film. The result looked like glass after a few coats. It seems like that would be more durable than a traditional finish? ...and hold the wood together?

3) I know it is a sin, but I would like to finish the top like the image I attached, what color dye(s)  did they use? Would I dye the wood before the epoxy...or hardener?

 

Any instructions advice or comments would be greatly appreciated,

 

Ron

[Prostheta]

Hi Ron,

Firstly, I wouldn't use a hardener since they're more designed for exterior wood products. I've been helping a colleague with advice to restore an old wooden house in Pori. They're designed to solidify the wood so you can use filler and then paint over it. That's not what you're going to do here, right?

The most common method of stabilising spalted wood is with superglue; specifically a water-thin type which has a far lower surface tension than any epoxy will have. The spalted wood will absorb that and become like glass. The downside is that it will not accept dye. It is what it is.

The forearm contour will be a challenge, definitely. Wood can easily crack instead of bending. It is possible to use heat to relax the wood, however you should probably practice this first instead of practicing on your workpiece. Water helps diffuse the heat around and stops scorching.

I would say that the top you posted was likely a burst of toner coats. That is, not dyes in the wood but slight tints added to various clearcoats being shot over the top.

We can help you get through this pesky guitar-building affliction Ron. 

Post photos of the body and the top and we'll figure out what's next, plus a what to do, and what not to do, etc.

[ScottR]

What he said.

In regards to your questions of color, I would say that is Amber, Mahogany brown (or similar) burst  and a black burst around the edges.

SR

[Dr Ron]

I just got the top today....yay! It's beautiful!

i see right away it is rough sawn so I'm going to do the router sled jig and get the boards thicknessed. I also see that I'm going to have to spend some time on the shooting board to tighten the book matched edges.

there is a nasty bark inclusion which is just within the neck pocket...it is a neck through body.

so dying the wood before super-glue is a no-no? Do they sell large sized superglue amounts? Is there any particular size? ...manufacturer?

 

 

[Dr Ron]

https://www.dropbox.com/s/z5z7zjsowcg85k9/Photo Jun 08%2C 4 19 42 PM.jpg?dl=0

[Prostheta]

Can't see the photos. They'll be private on Dropbox so you will be able to see them since your signed in. We can't!

[Prostheta]

I'm unsure about dyeing prior to stabilising. I couldn't say either way. Toner coats is how that burst was done.

How soft is it anyway? If it's punky and crumbling, you can't avoid stabilising it. I've found that some soaked pieces are no softer than say, Koa, and you can obviate stabilising. If it's still strong and doesn't need it, you can dye the wood.

Not sure of sources other than LMI or StewMac in the US. I'm sure it's available online from other places too.

[Dr Ron]

Sorry about the pictures issue 

They should show up now.

Im not sure what pinky is but there is that rotted knot at the top...luckily the neck cutout will eliminate that.

 

[Dr Ron]

https://db.tt/tJ6NvPKu

[Dr Ron]

[Prostheta]

The whiter areas tend to be the softest. Bear with me and I'll go into this in more detail. I have to go toy shopping for my current projects!

[Dr Ron]

Okay...thank you! Happy shopping!

[Dr Ron]

I want to get started this weekend so for step 1...I want to use a routing sled to thickness the wood.

Should I do the CA or epoxy?

Should I do that before I thickness it? (seems like I would be just routing throughout the epoxy/CA?)

Im not fearing chunks because I'm going to do some Turquoise inlays on the top. If the top holds together do I just carve some "fake" splits to fill with the epoxy/turquoise?

 

I'm going to keep the top as thick as I can and mill the body down so that when I add the top it results in a body that is the same thickness as the original body.

[ScottR]

Water thin CA will soak in the deepest and therefore do the most stabilizing. As far as before or after, it depends on the condition of your wood, but it is very common to need to stabilize before you can do anything at all to it.

If you go with CA you may get a spot of two where is soaks in deeply and flashes off. It will smoke and bubble and crackle and pop generally be a big surprise when it happens. Don't breath the fumes. When it's done go ahead and fill it again.

And yeah, if you don't really have any voids, did out some of the punkiest areas for filling.

SR

[Dr Ron]

Thank you for your reply!

 

Is there a CA I can buy at Home Depot or Lowes?

 

How much will I need?

[ScottR]

I usually use the thin version of this stuff from Rockler, but the medium works too.

http://www.rockler.com/quick-set-glue-4-5-oz

Home Depot has Locktite brand, or maybe titebond CA and the thin versions work as well  A 4.5 oz bottle should be more than enough.

SR

[Dr Ron]

Thank you...I really appreciate it!

To bend the wood for the forearm contour I am going to route grooves in the bottom. Will the super glue help or hurt the bending process?

[ScottR]

Well.........I don't recall ever seeing anyone bend a spalted top. Given that CA is more flexible than you'd expect, and softens with heat, and that spalted wood could just as easily break as bend, I'd say the odds are better that it would help. On the other hand, it is not going to let any or much hot water or steam penetrate the fibers, so maybe it's 50/50 either way?

Sorry, that's not much help.

SR

[Prostheta]

Sorry I took so long to respond. The way I would approach this is only my own opinion. I've not done a spalted wood forearm contour, so this is simply my train of thought.

Firstly, I would not use a hardener prior to bending. Brittleness in any form is not ideal. I'd want to use the wood in a form that it is most workable in. Heat is the key, however the bend should be done slowly and carefully. If the wood doesn't want to go, it'll be happy to tell you that. Routing relief lines in the back to encourage the bend might work, however it has failed on me more than once. Simply, it gives the wood a quicker route to crack.

I would clamp across the top prior to the bend with a caul  and encourage the bend closest to the folding point. Slowly. It's right at the end of the night here so I'll have to check in on this again tomorrow. This can be managed, however it has to be done right. Don't rush into it.

[Dr Ron]

That is  A conundrum.   I have to mill the spotted maple first so I can get it to the appropriate thickness but I'm afraid to do that without using this CA glue first . 

[Dr Ron]

 And that'll take at least an eighth of an inch off of my 3/8  sickness… What should help in the bending process 

[Dr Ron]

 Is there anyway to test to see if the wood is going to bend?  Preferably before it breaks? 

[ScottR]

Sure. Layout your pattern on the top and see where the scrap will be. Cut off some of it and test your milling and bending on that.

SR

[Dr Ron]

What if I use a vacuum pump? Will that do a better job? 

[ScottR]

Depends on it you can use it in increments. My understanding is the bend requires water-heat-steam, bend a little, heat-steam some more, bend a little and so on.

SR