Questions on carving 1x12 pine

[pn14427]

I have done 2 carvings on 1x12 pine from Lowes.
Both signs have started to cup toward the face. about 1/4 inch any ideas on how I can stop or limit the cupping. Even to use hardwood I have notices a little cupping.
Here is the latest carving I am doing for my sister-in-law.
I would value any advice

[fwharris]

Pine is probably the worst for cupping. My guess is you probably had to even sort through the stack at Lowes to find one that was close to straight.

One tip shared here was to seal the end grain on the boards when you get them home to your shop. This prevents the board from taking in any moisture.

Caring to deep and removing large areas of the board will also lend itself to cupping and warping.

[bergerud]

Would it be better to carve one side Vs the other? It seems like carving on the convex side would be better. As it dries in reaction to the carving, it would straighten out?? When sorting through the wood pile, I would look for the boards which are closer to 1/4 sawn as opposed to plane sawn. (End grain perpendicular to the board as opposed to end grain parallel to the board.)

[Geomoo1]

The wider the board the easier it will cup be it pine or any other species. Some just more than others. The trick to minimizing cup on any wide board is to rip it into smaller (say 4" wide) boards and glue them back together to whatever width you need. A 12" wide board will warp and/or cup no mater what. It's just the nature of wood. Also, as bergerud said, quarter sawn wood will have less of a tendency to cup than the others.

[lynnfrwd]

Does poplar warp like the pine does?

[mtylerfl]

Does poplar warp like the pine does?

Yes, it sure does...and so does Oak, Maple, Birch, Beech, etc., primarily in widths over 6" to 8".

Wood will tend to cup towards the side that the carving was done on (i.e., any wood removal on just one side of a board will promote warp/cup). Sign makers who deal with large dimension wood have a number of techniques to minimize this. One common technique is to do a shallow pocket carve on the backside of the board to help compensate for the difference in moisture content between the two sides. It's this difference that contributes most to the cupping, and the backside pocket cut evens out the moisture content from front to back.

BTW, I had a carved box lid cup terribly once (by about 1/4"), so I carved another from an older board which did not cup as much (hardly noticeable), and used that one instead for that project. A few days later, the original box top I had was almost perfectly flat again, all by itself! It just had to have a chance to "even out" the moisture content...and that one did NOT have a backside pocket cut into it.

Now, another thing to pay some attention to is placing the topside of the board to be carved in a certain orientation. To describe this is not as good as showing you a photo. I'll go out to the shop and take a pic of a clipping out of an old woodworking book. I keep this taped to a countertop next to my CNC machines as a constant reminder. Placing the wood this way will also help minimize the cupping tendency. Hold on while I go out to take the photo...

Ok, here's the photo. You'll see I have marked the word "UP" on the top illustration...this is the side that faces up for carving when I place it into the CW or onto the ShopBot bed.

[dehrlich]

The pine you get from home centers is generally higher in moisture content than normal. If you can find a hardwood supplier in your area it's better to buy from them. I get my pine from such a supplier, it's drier and generally more stable. It's not always true that wide boards will cup, I have used oak, walnut and other species nearly 18" wide that stays flat... it all depends on how it's sawn and dried. It is better however to rip the boards down and glue them back. Even if you glue it back the same way it was it helps because you limit the stress. About the only way to deal with a board already cupped is rip it down, flatten it and glue it back. I have tried carving on the convex side as was suggested, to see if the resulting cup would make it flat. The only way to do this is use a sled, as the edge will lose contact with the tracking wheel.

Even using narrower boards, or glued up panels, you will sometimes experience cupping from the carving. The whole trick is getting stable material to start with, storing it properly and making sure it's acclimated before you carve it. If there is time, I will clamp or weight the board so make it stay flat after carving and let it be for a few days, so that as it adjusts to the missing material it will stay flat. Seems to work but there is not always time. Dealing with wood movement is one of the most tricky problems we have to deal with. I am fortunate that here in Kansas the climate is such that wood doesn't move much once finished if built properly to begin with.

Bread board ends are another option, works great and looks good too. It all comes with experience. Good luck and keep at it!

[mtylerfl]

That is good additional info, Darren. I also do all of the above and more. Wish I could find a nearby place to get quartersawn wood...almost no issues with cup, etc.

[mtylerfl]

I have done 2 carvings on 1x12 pine from Lowes.
Both signs have started to cup toward the face. about 1/4 inch any ideas on how I can stop or limit the cupping. Even to use hardwood I have notices a little cupping.
Here is the latest carving I am doing for my sister-in-law.
I would value any advice

Be sure to avoid the "cheap pine" section...go for the kiln dried Select Pine. Select Pine can/will cup too, but will not have as much tendency as the "wet" stuff they sell on the other side of the aisle. I pick through the Select Pine pretty carefully when I shop...I lift each board, the lighter boards "win" because this is an indication (not a guarantee) the lighter boards will have a lower moisture content.

My hardwood source does not allow anyone to "pick" their wood in the warehouse. You place an order at the front counter, it's picked by a warehouse guy, then drive around to load up. If any of the boards are not acceptable, they will go get another (and another) until you are satisfied. Not an ideal situation, but that's the way it works for us here.

WoodCraft (one an hour south of me and another an hour north) has their wood on display in front and you can pick out what you want...but, the prices are fairly outrageous, so I had to eliminate them as a source a long time ago. I do much better with the source described above.

[James RS]

I had this happen on a project that i mounted my carved board to. I had glued it up and clamped it, when I came back the next day
it had cupped. I did some searching and found a video where a guy showed how to fix it . So I did what he did and ran the board through my tablesaw
cutting slots on the back approx 3/4 way through. Then a cut strips to fit and glued them in and clamped it flat, it now hangs flat on the wall hanging our coats.

[RogerB]

Grain stress. This will also cup a board. Removing a lot of wood from 1 side. Glue up your wood in strips 3 to 4 inch flipping the grain is the best way to fix this. You can also glue Baltic Birch plywood to 1 side router the edge and fill the end grain. This is also used for thin carves 1/2 to 1/4 inch to strengthen for apliques.

[Elmo Sr]

That is good additional info, Darren. I also do all of the above and more. Wish I could find a nearby place to get quartersawn wood...almost no issues with cup, etc.


they might have quarter sawn where we picked your wood up, I have never asked, I will call and find out. If we can cut this cedar tree down in my yard I will git sawn up only problem is the boards will only be 6-8'' wide

[mtylerfl]

they might have quarter sawn where we picked your wood up, I have never asked, I will call and find out. If we can cut this cedar tree down in my yard I will git sawn up only problem is the boards will only be 6-8'' wide

Thanks, Lonnie. Please let me know what you find out.

[dehrlich]

My nearest hardwood supplier lets you pick what you want... from what they have on the rack anyway. The price on Select pine here is such that I am better off buying red oak. When I had my hardwood supply really going I did two things; I would buy the bulk standard stuff from a wholesaler and I would get what they sent on the truck, usually good stuff. I would also go to a large saw mill and get some specialty lumber, like sycamore and hackberry. I would also pick through the piles of rough sawn walnut, cherry, oak and maple to find special boards that were figured or super wide. I would sometimes spend a whole day going through the warehouse and bring home a pickup load of really cool boards to sell. I still have some of the really unusual ones in my personal stash.

One suggestion I would make, on the US forestry website for most states, they have a listing of people who run sawmills, small and large. See if you can find ones that are in your area and check it out. You can find nice lumber and a fraction of the price they home centers charge. A lot of them will surface it for you. If they don't offer that, check with your local high school and see if they teacher will let you use the equipment to mill your lumber... most will if you ask nice. I donate lumber to low income students to build projects every year, and that buys me the chance to use the 24" planer or 37" sander when I need to.

[pn14427]

Thank you gentlemen for your input. Since this is a freebe for my sister in law i am using cheaper wood
We haveba couple of chainsaw mills around here i will ask around for quartersawen lumber.
Thanks for all your help and advice