# Thoughts on wood types for CNC routing



## Cncest (Apr 26, 2020)

Just wanted to start a discussion on types of wood for CNC routing. What gives the best finish with the least post processing.
Personally I get excellent results with walnut, cherry and maple.
I won't use hickory, too stringy.


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## kp91 (Sep 10, 2004)

Interesting topic, but it depends a lot on the type of woodworking you are doing.

I don't usually get to pick what I use. My 3 favorite woods are: Free, Cheap, and whatever the customer wants. I am not in the 'high end' business, I make a lot of props and decorations for School plays and events, Church events, Scouts, and donation items for the Dog Rescue fundraisers. As a result I am scrounging reclaimed materials, getting donations, or buying hardwoods cheap at auction. When I do get a paying gig then I get to use "nice" material (unless it's going to be painted by the customer). I have had to de-fuzz a lot of MDF over the years, but the finished projects look great.

I do like cutting Corian, but I have cut everything from MDF and construction lumber to Mahogany. My workspace isn't climate controlled, so I think that plays as much of a factor in what woods require a lot more sanding at different times of the year. I know everyone hates Poplar for some reason, but I have had great luck cutting it and made many engraved benches and signs from it. 

I cut a lot of mystery wood (free tables from Craigslist or the side of the road) with mostly good results. Some of the glued up tops from cheaper furniture will have huge differences in grain between the individual pieces and I have to watch the machine really closely as it goes from dense wood to easy cutting wood.

Use sharp bits, watch your speeds and feeds and have the wood dry enough and you should be ok. (except with the construction lumber, that just is absolutely horrible to work with....)


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## difalkner (Jan 3, 2012)

Probably 90% of what I do is Walnut with some Cherry and Maple mixed in, at least as it relates to the CNC. Discounting all the Longworth chucks I cut out of 1/2" BB, of course, but those are just flat pieces cut, no engraving.

David


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## MEBCWD (Jan 14, 2012)

Dan, walnut, cherry and maple cut well and are good for most projects as you have found and can be found for a decent price. The important thing is to make sure they are not something freshly cut from a sawmill. They do need to be well dried to get good results for CNC use. Actually, each and every board can present anywhere from great carves with very little cleanup to poor carves with a lot of cleanup time involved.

Construction grade lumber might be kiln dried but not to the same levels as hardwood lumber. It is also softwood and tends to cut poorly, often leaving a lot of strings and small tear-outs. I don't even recommend it for test cuts.

When you get into the hard exotic woods, some like wenge can pose a problem if using dull bits or bits with the wrong geometry. Wenge is often dry and brittle and tends to split but when cut but using sharp tooling will need very little cleanup. It is a good wood to use if you are looking for a very dark to black color but can often hide fine detail because of the dark color. It is a good wood to use for contrasting on-lay work.

Then there are heavy, hard exotics like Cocobolo, normally very high in cost, that contain a lot of oils. Projects are almost polished when cut, brush off the dust and chips and it is ready for finish. I love using it for small intricate 3D carves but can't justify the cost for medium and large projects.

I think the biggest consideration when picking wood for CNC use is the cost. 

If you are just a hobbyist and hang most of your projects on your own walls then you might want to branch out and use anything you see that catches your eye for one reason or another. You might like the color or maybe some really squirrely grain of some exotic burl. Or you might be trying your hand at Intarsia type projects where you mix a lot of different colors and grain patterns for your project. It is different if you are giving you projects away to family and friends, I'm talking about the everyday experiments and test cuts you make, not projects you make for special occasions.

If you give away a lot of projects then you might want to consider the cost of the wood you use. Choose something decent that cuts well so cleanup doesn't take forever and make the project a pain in the neck, instead of a fun to make gift.

If on the other hand, you are making projects to sell, you will want to use expensive exotics and burls only as small projects like jewelry or separate elements of larger projects. That brings you back to the standard native woods that are readily available and affordable. You don't have to buy wood from a store or reputable mill you can often find table leaves or whole tables at garage sales that make blanks for project. Don't pass up an old dresser made from hardwood that needs work, pull it apart, and use the parts for projects. If you have the room to store it and equipment to process raw lumber then you might consider that free choice of project wood.

The big thing to remember is to use sharp tooling and don't be afraid to test cut new-found materials, you might find a new favorite wood or material.


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## Cncest (Apr 26, 2020)

Has anyone tried other materials. Like plastics, ivory, bone, ect?


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## MikeSibley (Aug 11, 2020)

I have a great source for mahogany and use a lot of it for traditional woodworking. Has anyone had significant experience with mahogany? I tried to cut some pocket hole plugs out of it and that was a disaster as it fuzzed and splintered. I used the Kreg plug cutter, so when my machine arrives (tick, tock, tick tock .. waiting) I'm looking forward to trying it. I'm planning to develop some small v-carve projects and some small 3D items to run on different woods and see how they turn out, somewhat as a test. 

I have been accumulating bits in the same manner, one cheapie, one good one of the same type (tapered ball nose, end mill). My experiments will lead me forward. Maybe the feeds and speeds modification might find the best method of cutting different woods. Since I am new to the CNC world, I know it will be a challenge since rpm and manner of feed on my regular router table makes a huge difference on my router table. I'm concerned too about going to slow and burning the material and overheating the bits. If I ruin a $10 bit, I wouldn't like that but it is way better than destroying a $60 bit!

I am just guessing that you learn as you go, but the combined knowledge base of this group is wonderful so if you have any material suggestions, I'm all eyes or ears or whatever you say on a forum!

I think that i mentioned this previously but I have the materials to make the AvidCNC dust shoe out of HDPE. Can I use a regular 1/4 inch upcut end mill to rout that? I'm assuming slower spindle speed for heat and melting purposes. Any advice frome someone who has done it?


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## difalkner (Jan 3, 2012)

MikeSibley said:


> I think that i mentioned this previously but I have the materials to make the Avid CNC dust shoe out of HDPE. Can I use a regular 1/4 inch upcut end mill to rout that? I'm assuming slower spindle speed for heat and melting purposes. Any advice from someone who has done it?


Use an O flute made for plastic; it'll work great. I keep the spindle at 18k rpm and the feed rate around 125-175 ipm when I cut plastic, depending on depth of cut and the actual material being cut.

David


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## Cncest (Apr 26, 2020)

difalkner said:


> Use an O flute made for plastic; it'll work great. I keep the spindle at 18k rpm and the feed rate around 125-175 ipm when I cut plastic, depending on depth of cut and the actual material being cut.
> 
> David


I'll have to try out an O flute bit.


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## Oscar36 (Feb 23, 2019)

Here are my experiences. Like most folks I have gotten excellent results with walnut, maple, and cherry. 

Oak does well for me as well. I've done a half dozen family crests and many small trinket boxes using it with good results. 

African mahogany worked well. Only one really stringy cut out of dozens of projects.

Alder carved okay. Only limited projects with this species. Not a lot of issues but can be stringy. 

Cedar was hit or miss based on the tightness of the grain but generally okay results.

Purple heart is awesome to carve. You have to be careful handling it since the carved edges can be razor sharp. I've sliced myself in the past with it. Needs a sharp bit.

Padauk carves wonderfully as well. Also needs a sharp bit. 

Pine is all over the place from smooth as silk to straight to the firewood pile (mostly firewood pile). 

And all of my test cuts are in poplar. Fuzzies but easy to clean.

For an example of a pine carving that destroyed my preconception. I meant to carve this model in maple but wanted to test carved it in pine (construction lumber) first but the resulting carve was so pretty I used it instead for my project. Stained the surrounding rock to make the figure stand out more and framed the carving with mahogany and black walnut for back and base. One of my favorite pieces.


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## MikeSibley (Aug 11, 2020)

difalkner said:


> Use an O flute made for plastic; it'll work great. I keep the spindle at 18k rpm and the feed rate around 125-175 ipm when I cut plastic, depending on depth of cut and the actual material being cut.
> 
> David


Single or double flute? I don't want to melt it. Saw some post about bits melting plastic. Just asking!


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## MikeSibley (Aug 11, 2020)

Oscar36 said:


> Here are my experiences. Like most folks I have gotten excellent results with walnut, maple, and cherry.
> 
> Oak does well for me as well. I've done a half dozen family crests and many small trinket boxes using it with good results.
> 
> ...


My source is "real" mahogany whatever that means. It is not the African variety, I believe that is called sapele. I have a source with a really good price. I'm going to experiment, after all, if it is an experiment I cannot screw it up, right?


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## difalkner (Jan 3, 2012)

MikeSibley said:


> Single or double flute? I don't want to melt it. Saw some post about bits melting plastic. Just asking!


The one I use is a 1/4" single flute spiral and cuts like a hot knife through butter on cast acrylic and HDPE. It produces shavings with no hint of melting.

Here's a video I made about 3 years ago showing the bit cutting some thick Plexiglas. Today I would cut this much more aggressively but 3 years ago I was still very conservative in my feed rate and depth of cut.

Go to about 3:24 if you want to see the bit up close - 





David


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## difalkner (Jan 3, 2012)

MikeSibley said:


> My source is "real" mahogany whatever that means. It is not the African variety, I believe that is called sapele. I have a source with a really good price. I'm going to experiment, after all, if it is an experiment I cannot screw it up, right?


'Real' Mahogany is Honduras Mahogany, also called 'Genuine' Mahogany, Latin name is Swietenia Macrophylla. African Mahogany is a substitute for Genuine Mahogany but it is in the Mahogany family. Sapele is in the Mahogany family, as well. We see all three in the acoustic guitar world with Honduras Mahogany being the most sought after and hardest to find in decent quartersawn billets or pieces.

David


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## Oscar36 (Feb 23, 2019)

David, is on the money but it does get complicated. 

This is one of the best videos explaining all the Mahogany naming issues.


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## kp91 (Sep 10, 2004)

Cncest said:


> Has anyone tried other materials. Like plastics, ivory, bone, ect?


Lots of Corian, it is awesome to cut


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## MEBCWD (Jan 14, 2012)

I have cut Abalone shell for inlay work for some guitars. I used bits made for cutting it, shallow passes slower feeds per their recommendations. https://www.precisebits.com/products/carbidebits/shell.asp

I also agree with Doug Corian is great to work with, machines cleanly with little clean up most of the time.

I have also used a lot of Sapele for jewelry sized 3D items and it machines well and cleans up easily. See the router tie tac bottom center.


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## honesttjohn (Feb 17, 2015)

I use a lot of pine, in premade blanks from Brazil, as well as New Zealand 5/4 select pine -- both available from Menards. Construction grade s++t from the big box stores suck. And their finished boards are usually too expensive with a lot of crap.

I also got a lot of glued up birch, oak, aspen, poplar, and maple boards usually in 1 or 5/4 x 12 x 48. Using the glued up boards prevents most warping and bowing. They are factory finger jointed and pretty much defect free. But you have to keep an eye out when they are available. The birch is probably my favorite (I've used over 300 of these boards so far), followed by the oak. Maple carves great but is harder to come by for me. The Aspen and Poplar are pretty much for text signs only as they leave too many fuzzies to clean up. They Vcarve cut easy and finish pretty good as well as being cost effective (cheap).

I've even taken logs, sliced them with a chain saw and made some pretty good things. 

You just have to constantly keep your eyes open and jump when the opportunity presents itself. And stock up when you can.

You can also glue up your own stock. If you're carving them then the seams don't have to be perfect - just a good snug fit. Clamps and glue can make some nice material to work with.

But like said earlier keep an eye out for free and cheap. Always be on the lookout and ready to pounce when something pops up.

You'll soon have a preferred list of materials you like to work with. Everyone is different.

And keep your cutoffs and scraps. They can be used until they are almost dust and chips.

Don't be afraid to experiment.


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## marecat3 (Nov 30, 2010)

for 3d carving mostly use oak and some cherry. All depends on what the customer wants.


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## jreed983 (Jan 9, 2017)

honesttjohn said:


> I also got a lot of glued up birch, oak, aspen, poplar, and maple boards usually in 1 or 5/4 x 12 x 48.


Where do you get these boards from?


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## honesttjohn (Feb 17, 2015)

jreed983 said:


> Where do you get these boards from?


I usually get them from Menards. I have established a relationship with one of the wood buyers at their WI HQ. He usually lets me know when they have a "special"coming up and can most often scrounge up some things when the stores are sold out.

They have a relationship with several mills here and in Europe and will, from time to time, buy several carloads of glued up boards that the mills put together once or twice a year (probably their saved up scraps) and offer them on a one time basis as a discontinued item. You just have to watch for them to come up and then pounce. I've bought out the 3 stores near me several times just to try and keep material on hand.


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## Brand new (Jan 10, 2022)

MEBCWD said:


> Dan, walnut, cherry and maple cut well and are good for most projects as you have found and can be found for a decent price. The important thing is to make sure they are not something freshly cut from a sawmill. They do need to be well dried to get good results for CNC use. Actually, each and every board can present anywhere from great carves with very little cleanup to poor carves with a lot of cleanup time involved.
> 
> Construction grade lumber might be kiln dried but not to the same levels as hardwood lumber. It is also softwood and tends to cut poorly, often leaving a lot of strings and small tear-outs. I don't even recommend it for test cuts.
> 
> ...


Dan, I know you posted this awhile ago. I am just in the process of setting up a cnc router and a separate laser. The answer you gave was so helpful as I have never done cnc before. Could anyone tell me if I can use black walnut, that has only been dried for one year, to use for routing or laser? Thank you


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## Cncest (Apr 26, 2020)

Black walnut cuts very well in a CNC router. I would say one year curing should be ok. You'll have to try some to be sure. I don't have any laser experience. But it should be fine also.


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## Brand new (Jan 10, 2022)

Cncest said:


> Black walnut cuts very well in a CNC router. I would say one year curing should be ok. You'll have to try some to be sure. I don't have any laser experience. But it should be fine also.


Thank you, I appreciate your quick response.


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## old55 (Aug 11, 2013)

Welcome to the forum @Brand new


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## Brand new (Jan 10, 2022)

old55 said:


> Welcome to the forum @Brand new


Thank you, it is great knowing you can get a quick response to an issue. Because this is my first time doing cnc routing and laser, (having both is a long boring story) I will appreciate the help. After I figure out how to turn on this computer I will be set to go.😁


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## TimPa (Jan 4, 2011)

closed grain woods seem to fair the best when cutting on the CNC, and light colored woods provide the best contrast when engraving with the laser. e.g. laser on walnut is difficult to see...


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## difalkner (Jan 3, 2012)

Brand new said:


> Could anyone tell me if I can use black walnut, that has only been dried for one year, to use for routing or laser?


How thick is the Walnut? Do you have a moisture meter?


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