# which is a good wood for a relatively large project?



## halfmoon (Sep 29, 2020)

I'm going to be carving a live edge slab into a Celtic Cross- a much bigger project than anything I've done before- and am asking for advice about the wood options at a local lumberyard. They have a good selection of live edge slabs that have been kiln dried. I'm looking to get a slab about 36×25-30 inches and 2 1/2- 3 inches thick. I'm assuming the closer the board was to the center of the tree the less likely it is to warp or cup. These are the selections they have on offer:

Bay Laurel
Black Acacia
Claro Walnut
Deodar Cedar
Eastern Walnut
Monterey Cypress
Sycamore
Valley Oak

The finished piece will be outdoors so a wood that has at least a little weather resistance is preferred. The fact that it will degrade over time is part of the project. Any guidance is greatly appreciated.


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## Unknowncraftsman (Jun 23, 2013)

I have no idea what your answer is. Most will go to the lumber yard and look to the wood for guidance I don't see how a perfect stranger can know.
I do think it's cool that you're lumber yard have Deodar cedar. ( true cedar)

Good Luck


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## ibewjon (Oct 2, 2010)

Sycamore will rot quickly. The cypress in the Midwest is rot resistant, I don't know about monterey cypress.


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## Phil32 (Aug 31, 2018)

Why would you choose a live edge wood for carving a Celtic cross? The outline of the cross should be the edge of your carving. Re: the wood: I have a large outdoor carving that has survived nicely for twenty years. It is "Redwood" (actually Cedar) from a Big Box store. Design the cross and its placement to shed rain water.


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## CaptainKlutz (Apr 23, 2014)

Hmm, Let us look these up:
https://www.wood-database.com/wood-finder/

Black Acacia is generic name. 
If it is ironwood, it is rock hard, tough on tools, and near indestructible outside.
If it is black wattle, has about same properties as walnut - not so good for being outside all time.

Bay Laurel is Myrtle species and not very good outdoors.

Cypress and Cedar have similar outdoor durability and bug likeability. Work OK outside. They are softer and would be easier species to carve on list.

White Oak is great outdoors, but red oak is not very good as it open pores. 
Most of the S. CA oak I have seen is California black oak which is cousin to red oak and listed as not durable outdoors?

Best Luck.


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## drsurfrat (Aug 17, 2020)

I don't think nearness to the center has to do with the cup or warp of a board. I have found that right at the pith is very unstable. The *angle* from the center of the tree is the better pursuit. Radial (i.e., quatersawn) is the most stable.

Will it be inside? outside? planted in the ground? Big differences to the life of the cross.

Useful general guide, (your woods are not listed, though).
https://www.rockler.com/wood-species-guide

for stability:
https://woodwright.net/wp-content/uploads/2013/07/Stability-Wood-Flooring-Chart.pdf

rot resistance:
https://robidecking.com/wp-content/uploads/2017/01/USDA-rot.pdf


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## halfmoon (Sep 29, 2020)

Many thanks for the advice and resources!
I'm using a live edge slab simply because that seems to be the only way to get a single piece of wood wide enough that isn't glued, as I need to avoid glue as it will be outdoors. I live on the central California coast where we get much more sun than rain and it will be under a tree. I may put it under cover when a storm is on the way. I've thought about redwood but don't think it will take as much detail as I'd like to get. I'll either make a separate replaceable stand or make holes in the bottom for stakes to stand it up with.

Thanks again for the help!


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## drsurfrat (Aug 17, 2020)

Ok, if you will put up with more opinion, I grew up in So Cal. I don't think you need to worry about stability, it's a single piece and will move all together.

Rot resistance will be more important, the suggestion of white oak seems like a good one and apparently valley oak is one of them.
from Wikipedia: "*Taxonomy* Valley oak is of the white oak evolutionary lineage, which is officially known as the subgenus Lepidobalanus."

I think the most important part is termite resistance. We had a *redwood* deck turn to powder from them. They are terrestrial "dry wood" termites and can survive in wood down to 3% moisture. Make sure that there is no direct path from the dirt to the wood. Setting it on steel posts works. If you can, seal the bottom with Henry's roofing tar. It's incredibly messy, but eventually hardens to a pretty impenetrable barrier. Your aesthetics will be important, but these things might help it last.


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## John Smith_inFL (Dec 15, 2017)

HalfMoon - welcome to the forum !!
when you get the wood on hand and start your project, please make a project page
for it so we can follow your journey.
will you be carving it by hand, router, or CNC ???
do you have a design or sketch on paper yet that you can share ?

.


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## Phil32 (Aug 31, 2018)

I would suggest not carving the Celtic cross with only vertical grain. Even with the ring, the arms of the cross are cross-grain, making them easily broken.


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## halfmoon (Sep 29, 2020)

Thanks again for the replies. I viewed the slabs today, they're ok but something thicker than 2 1/2 inches would be nice. When I first looked for wood I searched for something 6-8 inches thick and 20-24 inches wide and found nothing, but perhaps I wasn't looking in the right place. I need at least 4 feet. Any suggestions?


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## ibewjon (Oct 2, 2010)

Keep looking. Find a small mill or a woodmizer owner and have the slab cut to order.


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## Lazyman (Aug 8, 2014)

The problem with using a slab that includes the center of the tree is that the juvenile wood at the center is likely to crack and warp. If possible, you would be better off finding a slab that does not include any of the first 10 or so years (rings) of growth. Juvenile wood at the center of the tree shrinks and swells at a higher rate than mature wood and is what causes the worst cracking and warping in wood. Assuming it will be displayed vertically and not in contact with the soil, it will be much more durable than say a table top, especially if it is protected from direct sun and doesn't have frequent wet and dry cycles. Also, with it going outside, you probably don't need it to be kiln dried so you might check on Craigs list or FB Marketplace for local sawmill or even just a guy with a mill selling slabs and see if they can cut you exactly what you want. It is likely to be cheaper than a lumber yard. Air dried wood may be easier to carve as well.


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## drsurfrat (Aug 17, 2020)

https://woodmizer.com/us/Find-a-Local-Sawyer
this list has icons telling who sells slabs.

http://www.woodweb.com/cgi-bin/directories/sdd.cgi

http://portablesawmill.info

https://woodfinder.com/search.php


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## PBWilson1970 (Jan 23, 2020)

> I would suggest not carving the Celtic cross with only vertical grain. Even with the ring, the arms of the cross are cross-grain, making them easily broken.
> 
> - Phil32


I agree strongly with this. Will you add some sort of mechanical fastener to keep the arms attached?

You could also think about using a half-lap, Lincoln-Log-style of attaching the cross piece. A well-fitted joint with Titebond 3 or a marine epoxy (West Systems is a great choice) will withstand the elements. Heck, Epoxies are used in boat construction and will see more moisture than your project will ever see.


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## halfmoon (Sep 29, 2020)

One sawmill has offered a 4-8 inch thick fresh sawn slab, undried. I assume it may split or warp over time, correct?
Plan A was to get a thick dried slab, and have the ends of the crosspiece extend no more than 5 inches out to the sides from the ring. I was thinking after carving it would still be at least 3 inches thick and that would be sturdy enough, despite the cross grain issue. Still a concern?
I was wanting to avoid glue for durability, but it sounds like epoxy may last. Is there any reason (other than cost) to not glue 2 pieces of 2 1/2 inch slab together with the grain running 90 degrees to each other to make a 5 inch thick slab? I would avoid having to notch out a channel for the crosspiece that way, which if it does separate over time would be in a bad aesthetic spot. It would be 2 pieces of slab glued horizontally.
I expect to oil it regularly, rather than polyurethane sealant, if that makes any difference on the durability of glue.

I really appreciate the help y'all are giving here.


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## Lazyman (Aug 8, 2014)

Grain on slabs glued at 90° angles to each other will not hold well with changing moisture content or as it air dries. Wood doesn't expand and contract much on its length but can change dimension significantly on its width. This may cause all kinds of contortions or it may just break itself apart.

If the undried slab has the immature wood from the center it will likely split and warp as it dries. It may not take long to find out how much but a 4-8 inch slab will literally take years to air dry completely, or at least reach equilibrium with the outside humidity levels. The fewer rings from the center you have the better. If it does split on one side but not so bad that it is at risk of breaking apart, you could fill the crack with epoxy and put that side toward the back side if there is one but you might have to wait a while before it dries enough that any significant movement has happened.


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## John Smith_inFL (Dec 15, 2017)

HalfMoon - can you show us a draft, sketch, drawing or plans for this project ?
it seems like we are grasping at straws in the dark to really address your concerns.

.


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## theart (Nov 18, 2016)

> Many thanks for the advice and resources!
> I m using a live edge slab simply because that seems to be the only way to get a single piece of wood wide enough that isn t glued, as I need to avoid glue as it will be outdoors.


Think about it this way, how often have you seen wooden exterior doors that are made out of a single slab? Don't fear joinery. If you start the carving with an assembly held together with mortise and tenon or lap joints it's going to hold up fine outside.


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## Unknowncraftsman (Jun 23, 2013)

Not very often are doors made with a single slab. Not a good idea if your planning on living the the house and using the door on a regular basis.
It's not uncommon to have a great idea for a project. It's also common to choose the wrong material or fall short with the skills to accomplish the idea.
I call it pipe dreams new woodworkers have them a lot.


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## ibewjon (Oct 2, 2010)

Maybe a single slab of mdf or particle board.


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## Phil32 (Aug 31, 2018)

> Maybe a single slab of mdf or particle board.
> 
> - ibewjon


The OP says he wants the cross to be 2-1/2 to 3 inches thick in a single piece. I don't think that is possible with mdf or particle board.


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## ibewjon (Oct 2, 2010)

No, not the project. I was referring to above post about a large one piece door being mdf or particle board. And old woodworkers have the same pipe dreams about projects. Those dreams keep us moving forward.


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## halfmoon (Sep 29, 2020)

Okay, hopefully the sketch shows up. Looks like it's going to be sideways, sorry about that. To think at one time I was destined to be an engineer….

Obviously, a rough sketch, the various parts aren't perfectly to scale. I don't want to put in the time to do the real thing until I have the wood and therefore the dimensions. It will be 20-22" wide, 32-35" tall plus a 4×6 base.

Plan A, if I can get a single piece of hardwood wide and thick enough (at least 4" thick) calls for the outside radius of the ring to be 8 1/2"- 9", inside radius 6"- 7", so the horizontal arms would extend a couple of inches past the ring and be 4" wide (vertical dimension). Knot work to be carved on the front will be 1/4" -3/8" relief on the cross itself, then another 1/4" down to the ring. The center of the ring won't be carved all the way through but will be carved out another1/4" or so in depth. The back will have a different design involving 1/4-3/8" relief over the whole thing. So the carving will result in a loss of thickness of about 1 1/2". Horizontal surfaces will be curved to shed water, and if we're expecting a lot of rain it will be brought under cover, and I'll be oiling it every year. There are two sources who may have lumber 5"x 22" (one is quartersawn), hopefully I'll know soon. So the question about Plan A is, are the ends of the horizontal arms at risk of cracking? They'll extend out from the ring a couple of inches, being 4 inches tall and (hopefully) at least 3" thick.

Plan B, by suggestion, is to notch and glue the cross piece, to minimize risk of splitting and cracking of the ends of the cross pieces. I assume to make the horizontal piece the dimension of the arm where it expends beyond the ring.

Thanks again for the help!


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## Phil32 (Aug 31, 2018)

The risk of cracking is greatest where the end grain is exposed. With your Plan A design, the top of the main member, the upper curve of the ring, and the upper sides of the cross member, but also the inner part of the lower half of the ring. The relief design within the borders of the cross should also shed rain with down sloping edges.

On Plan B the cross piece would be stronger, the ends would be subject to cracking, and the relief design would have to be adjusted for the cross-lapped joint.

All of these matters could be handled by thoroughly sealing the wood, especially the end grains.


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## dschlic1 (Jan 3, 2013)

Gluing multiple boards together with a water proof/resistant glue will work in an outside application. My recommendation is to purchase 12/4 white oak boards and glue then together into the desired slab size. You can also use loose tenons between boards for more security.


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## halfmoon (Sep 29, 2020)

Here is the design I settled on- the bulk of the cross is two pieces of slab glued together with the grain horizontal, with the lower vertical member, also two pieces glued together, notched into it. I scanned the final design but was unable to open it on my computer, hopefully these photos will work. The design on he back may change somewhat- hard to see, but it's mainly sort of a spiral

















My impression is that I now move to a project page.

rosette.

Thanks again for all the help.


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## John Smith_inFL (Dec 15, 2017)

thanks for the update !!!
I was wondering what happened to this project.
looking forward to seeing the process and the tools that you use.

John


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