Lube your coring groove

[Bob Bergstrom]

I core many of the bowl blanks that I mount on the lathe. I’ve found that a real plus in reducing stalling is spraying oil like WD-40 into the groove. The oil will lube, cool the cutting action, and assist in removal of the chips. As you watch the video listen to the sound without oil and with the oil spray.


https://youtu.be/2mSNgzAmbmg

[Pat Scott]

I've heard of this doing before, but all I can think of is what a mess it must make with WD-40 being sprayed all over, not to mention wasting a lot of expensive WD-40. I've also heard of using water, but again I'm thinking what a mess it must make with water dripping and being slung all over.

[Peter Blair]

So what happens to the wood where it is soaked with WD? I would think it would stink and possibly be difficult to finish?

[Bob Bergstrom]

Nope. The cores are rough outs. When finish turned, all surfaces are new wood. Water would swell the fibers much like it is doing when it stalling.

[Bob Bergstrom]

The wood was already wet. That’s steam coming out of the grove. There not that much oil being sprayed. The guy spraying may have been doing too much. The chips in the grove are aborning oil and lubing the grove as they evacuate from the grov. I haven’t found any evidence of oil being slung anywhere. The guy was being hit with chips when he raised his hand

[Peter Blair]

Thanks Bob!

[Stan Calow]

Do you think this would this work with a forstner bit?

[Reed Gray]

I used to lube the gate/fingers that keep the blade from twisting, but didn't find lubing the inside to help at all. Biggest problem with the McNasty is how it drifts to the outside during the cut. I tweak the tips in just a hair, and that takes care of it. Other alternative is to open up the kerf as you go in. If you don't, the blade is one curve and the kerf is another, which is what causes the blade to bind up during the cut.

robo hippy

[Bob Bergstrom]

Do you think this would this work with a forstner bit?
Works metal. Should work with wood. Any clear light oil would help cutting. I take it you would be hollowing after.

[Bob Bergstrom]

I used to lube the gate/fingers that keep the blade from twisting, but didn't find lubing the inside to help at all. Biggest problem with the McNasty is how it drifts to the outside during the cut. I tweak the tips in just a hair, and that takes care of it. Other alternative is to open up the kerf as you go in. If you don't, the blade is one curve and the kerf is another, which is what causes the blade to bind up during the cut.

robo hippy
Reed, isn’t that bending on your YouTube feed? I believe that is why many keep pulling the tool to the left trying to keep it tracking. The newer blades are poorly made and need attention.

[John K Jordan]

Do you think this would this work with a forstner bit?

Stan, long ago I hit on a way to drill with a Forstner bit. I direct a stream of compressed air into the hole while drilling. This not only cools the bit but clears the chips which also cools the bit and eliminates repeatedly backing the bit out of a deep hole.

I've used this method every since except for very shallow holes, say when drilling a shallow recess to hold a bowl/platter blank.

JKJ

[Reed Gray]

I can't remember if I put bending the tip into that video or not. I did show how to bend out the twist that happens to them much use and abuse/catches.... I have argued with Kel about the bends on his blades, and he insists they are 'spot on'... Maybe I will have to make my own... Bending that last bit near the tip is the problem if you are starting with straight blade stock. Next to impossible to get enough leverage to make that part follow the curve. Still experimenting.

Biggest problem I have had with forstner bits is trying to drill with them when they are dull. Like all bits, if you are drilling a deep hole, you need to clear the chips before they clog it up....

robo hippy

[John K Jordan]

Biggest problem I have had with forstner bits is trying to drill with them when they are dull. Like all bits, if you are drilling a deep hole, you need to clear the chips before they clog it up....


Keeping chips clear was the point of the compressed air - it magically clears as I drill. I started using this after a burned my finger on a bit that was hot from not clearing the chips.

To keep the bits sharp, I keep two sets. For woodturning and other holes where the smoothness doesn't matter so much I have sets of carbide bits, inch and metric. I've been using the same bits for at least 15 years and they still cut well. On the occasion where I need a smoother hole I use good quality steel bits.

[Brice Rogers]

When I'm using a Forstner and it seems to be getting too hot (steaming), then I sometimes squirt in some WD-40. It helps. Also, I haven't noticed any finishing problems. But I use primarily oils and solvent-based finishes rather than water-base.

[Don McClure]

I use acompressed air stream all then time when coring using the One Way system. It not only removes all the chips it cools the wood and cutting tip. And no mess.

[Dale Bonertz]

Bob,
I have been wanting for years to add this caveat to the video I have on youtube on the McNaughton system. I have been doing this for years and it does slick the wall to help with chip ejection. It also does not do anything to the wood as far as the finishing. I spray it as the bowl is turning and the tool is in the kerf. It does not gum up or have a chance to penetrate the wood to cause finishing issues. I am glad you posted this since it also helps cool the blade. As we know when steel gets hot it expands and the DW40 helps cool the blade therefore assisting in the advancement of the tool. I am typing this before I watch the video. I will now go back and see how you are spraying it to see if you do it similarly.

[Dale Bonertz]

Yes very similar except I spray it myself while coring. I spray out of the can with the straw nozzle. It gives it more of a direct hit and no splashing. Your system seems to work just fine. Good job.

[Peter Blair]

I'm gonna try that Don, thanks!

[Bob Bergstrom]

Yes very similar except I spray it myself while coring. I spray out of the can with the straw nozzle. It gives it more of a direct hit and no splashing. Your system seems to work just fine. Good job.
Dale, usually I do the spraying very similar to what you are describing. I relax the pressure on the tool and spray a stream of WD- 40 into the grove above the tool point. This video was taken at our club’s shop. I found a good spray bottle at the big orange store ($7) which has a good pump that shoots a good stream of oil like the straw on the can. I suppose it wouldn’t be too difficult to affix a straw to it. Usually there are chips above the tip of the blade point that absorbs some the oil and will rub against the wall of the cut. I can buy a gallon of WD-40 for $18. Thanks for the comments. I recommend your video to all that ask me about coring. It is so well done.