Best tool for turning large logs with big "air"

[bob drake]

Hi, I was trying to turn some found wood recently, large pieces 12-16" dia that were very irregular. I went thru pretty much all my turning tools and beat myself to death, but found that my small circular carbide scraper (12mm dia?) on a small (3/8" dia?) round shank seemed to give me the least physical "beating". I turned at various angles, which seemed to allow stock removal without too much of a beating. I'm wondering what tools others have found best to use to rough out odd shaped wood into bowl/vessels? I was thinking a stouter shank, maybe 5/8" or 3/4" would stand up better, and maybe a slightly larger carbide bit might be better, or at least faster? BTW, my small carbide has relief next to the cutting edge, chipbreaker I think it is called? Most of the bigger bits are flat carbide, I would think those wouldn't cut as well? It seems all the large commercially available tools with round carbide bits have a flat bottom on the shank, which I think presenting the cutter straight into the wood would beat the heck out of my arms? Any comments or experience would be appreciated!

[Chris A Lawrence]

Instead of trying to turn it round maybe use one of these https://www.harborfreight.com/22-too...isc-61638.html to get it into a rounder shape while it isn't spinning.

[Thomas Canfield]

I turn a lot of natural edge and other found wood often with large air space. I use standard 5/8" bowl gouge with swept back grind or on larger pieces (15"+) will use my 3/4" Thompson bowl gouge. There is a lot of getting beat, but a sharp tool and gentle feed helps to minimize the beating. I don't think about using anything except bowl gouges.

[John K Jordan]

I think the smaller and sharper the cutter the less the beating. Lisi Oland turned 40" bowls with 1/4" wide scraping bits, similar to what is often used for hollow forms. I sometimes even use a stout scraper with a single point - removes wood easier but tears it badly.

I usually use a Hunter carbide tools when cutting "air". These are not flat topped cutters but are dished with an extremely sharp edge, almost as sharp as a spindle gouge. I cut in the "bevel rubbing" mode, just like using a gouge, and take light cuts. You can use the same tools as scrapers too - very easy wood removal at the expense of a rougher surface. The Hunter Hercules is my favorite tool for cutting air - the shaft is very stout. I think the cutters are closer to 6mm. I suspect 12mm is trying to take too big a bite.

Another thing I do when cutting air is get the speed as high as safe. I often cut pieces with wings and the combination of light cuts with the small diameter Hunter cutter and higher speeds does wonders.

JKJ

[Bob Bergstrom]

Start with an electric chainsaw. Lock the spindle and carefully trim off the high spots (chains don’t like hitting the banjo of the lathe). I use a 3/4 Thompson with a ground back 40/40 grind. The flute is rolled over to a 3 o’clock position. If there is a lot of air, I will drop the handle and roll the fluet to 11 or 1 o’clock in the direction of the cut.

[Marvin Hasenak]

I have used a 4 1/2" grinder with a 40 grit disc on it. I slowly turn the wood by hand while shaping it round. I made a mount for my grinder that fits in the banjo. I move it closer as needed until I think I can turn on the lathe and use a chisel.

[Leo Van Der Loo]

Large logs that are rough and not round yet I have turned often enough, I find that where you start and the way you hold the tool makes a big difference.

Like in this picture I have started in the center and cutout to the side cut after cut, holding my ⅝” bowl gouge so it does cut, large curls rolling off the gouge, I din’t even bother to round the piece nicely round, as it does cut round easily this way, and trying to manhandle large pieces on a bandsaw isn’t easy.
rough turning large log.jpg


Having openings in the wood only ask from you that you do not shove the tool into an open part, taking the time and again having the gouge cut with ease so you can control the tool into the direction you want to go.
turning large bowl inside.jpg

Turning smaller pieces are much easier where you can speed the lathe up some, but still keep it safe, these pieces here below show that when going at it properly, it is quite easy to turn 10” - 12” bowls from wood that has pieces missing, just make sure you hold your tools so that they are cutting.

larger Oak burl bowl.jpg Figured Sugar Maple.jpg Large Acer Negundo burl bowl.jpg Tuja root burl vase.jpg

[Mike Nathal]

I like the "pivoting cut" described in this video by Brian Havens

https://www.youtube.com/watch?v=lexrdkV_cG8

[Steve Schlumpf]

Bob, I have 3/4" and 5/8" bowl gouges and prefer to use the 5/8" for almost everything. The key to success when turning larger forms remains the same whether the wood has voids or is solid and that is to position the tool rest close to the wood (minimizes overhang), rotate the gouge so that it slices the wood (Bill Grumbine's method of 45* - 45* - 45*), lock the handle to your 'turning muscle' and shift your weight to move the cut. The one key element to the 'turning dance' is to keep it slow and under control. You won't have any problems turning voids if you lock your position and shift your weight to move the gouge. Problems arise when you use just your arms for turning and you end up pushing the gouge into the wood when trying to rub the bevel.

[Prashun Patel]

I haven't turned nearly as many as these folks, but I was much more prone to getting a "beating" earlier on. It ultimately hurt my shoulder, elbows, and lower back enough that I couldn't continue.

I focused on gentler, higher speed cuts. Being too aggressive was causing me to push into that negative space. Be patient and gentle, and the tool length becomes less important.

My biggest tool is a 5/8" gouge, but I do most of my roughs with a 1/2" now.

[Reed Gray]

I don't turn pieces like that often, but prefer a gouge for that kind of work, and I use scrapers on every thing else bowl related. Finding one spot where you have the piece round all the way around, and use a pivoting cut from there and round it as you go rather than trying to nibble off down the whole outside, or inside of the bowl. You can not hog off lots of material on pieces like this.

I will have to check out the Brian Havens video above, his videos are pretty good.

Yup, pretty much what I do, well, when I use gouges. I do start near where the tailstock hits the wood and level that out to the rim. Mostly because the wood is moving slower there, so there is less impact.

robo hippy

[chris cullers]

1/2 or 3/4 bowl gouge with a fingerail grind would me my choice for that. light touch and keep the tool rest close. Light touch will allow you to control the cut.