Rough texture of maple grain

[Warren Grill]

I am a novice (< 1 yr) turner making small bowls and vases on a 1967(?) Craftsman lathe that I inherited from my grandfather.

My current project is to turn a small tray from a maple crotch (2 months drying outside) from a limb that came down in my friends yard.

While some of the grain turns beautifully smooth, other areas are very rough (please see photo). I tried sharpening the carbide that I am using, as well as using a very sharp scraper, but same problem persists.

I would appreciate any suggestions.

Thank you

 

[Brian Gustin]

Tear-out. You need sharper tools, ideally. The wood grain is too soft & dry (silver maple?) - you'd see the same results with Pine and other relatively soft woods, as well as punky areas of harder woods.. Only way I have ever had luck with those is getting my tools properly sharp, and using a very light touch on the cut... and a scraper is not gonna do the job, it needs an actual bowl gouge cutting edge (and most carbides are actually scrapers as well) (Hint: if your cutter is sharp enough to shave with, it still ain't sharp enough... it needs to be sharp enough to slice the fibers cleanly before they tear loose.. basically it'd be so sharp that if you cut your finger on the edge, you'd barely even feel it...)

At least that's my thoughts on it..

BTW, Probably posted to the wrong forum - this is announcements, rules & help, you'd get better results if it moved over to general discussion..

 

[Clifton C]

Sometimes punky wood is punky wood and might be past its expiration date. Super sharp tools, slicing cuts and extremely light cuts seem to help. Scraping has never worked well for me.
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[Emiliano Achaval]

The thread was moved. Forum technical support is for problems like how to post a picture, etc. My best advice will be to join a club if you have one close by. If not, the next best thing is to go to a class with someone like Jimmy Clewes in Las vegas or Ashley Hardwood in Charleston. A few days with either one would give you the knowledge and skills to keep practicing at home, safely and be able to have more fun.

 

[Bill Boehme]

I agree with Clifton. The gray color indicates to me that the wood has decayed and the tear-out is another indication that the wood has gone past its "best by" date.

 

[hockenbery]

While some of the grain turns beautifully smooth, other areas are very rough (please see photo). I tried sharpening the carbide that I am using, as well as using a very sharp scraper, but same problem persists.

I would appreciate any suggestions.

Getting a nice surface until you get past the mid point of the endgrain.

I suspect 2 main issues. 1 - the direction of the cut. 2- soft maple doesn’t scrape well.

Your big tearout area is on the back side of the end grain. A problem area in most turnings.
Cutting uphill downhill is all about having a longer fiber behind the one being cut.
When cutting toward the ways or scraping toward the ways there is only air behind the fibers on the back side of the endgrain so the fibers tear instead of cutting.

If you can cut toward the high spot ( down hill on the grain with the top of the hills being at the head and tailstock ends you will get much cleaner cuts. Easy with a gouge. Doable with some of the Hunter carbides.


If the wood is punky you may still get some minor tearout cutting in the proper direction. Thin shellac or thinned lacquer will probably stiffen the fibers enough to get a clean surface.

 

[robo hippy]

Yup, 2 problems, a soft maple, and scrapers for finish cuts. I don't like to turn our big leaf maple because it tears out more than a lot of other woods. A scraper, and even a NRS/negative rake scraper, will not leave a nice clean surface. You need a gouge for best results. I also use a shear scrape which works some times, and not others. Some times getting the wood damp and then, taking very light cuts, cut off the damp wood. When all else fails, break out the 80 grit gouge, aka sand paper...

robo hippy

 

[JeffSmith]

Seconding the soft maple comments - I turn a fair amount of Big Leaf Maple and end grain tear out is a problem in the softer maples. As Al shows, cutting direction -towards supported fibers - is critical, but there can still be areas that just won't respond, like the crotchwood where grain direction varies along the cut path. Sharp tools are a must - and remember that tool is only sharp for a few seconds after you've started your cut. Scraping - even shear scraping has not been a solution for me. Light cuts with a sharp 3/8" gouge ground to a 40-40 grind works best for me. A little misting with a water/soap mix can help but often there will be a very small amount that needs a hand scraper (off the lathe) or the good old 80 grit gouge to remedy.

On the plus side, soft maples give you the opportunity to try any and all tearout relief strategies until you find one that works for that one piece of wood - great way to practice tool control and get time at the grinder making sure your tools are scary sharp.