End Grain NIP Tear Ou

[Steve Doerr]

I have a large bowl that I have turned from a piece of end grain NIP. The problem is that I am getting some tear out in some of the growth rings. I've tried a lot of different tools, sharping frequently, and have found the best results with a traditional ground bottom gouge. I've also tried using shellac to help firm up the end grain, but it has not been totally effective.

So, how do all of you that turn end grain NIP keep from getting tear out? Since I cored this piece and have three other bowls yet to turn, any help you could give me would be greatly appreciated.

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[Brice Rogers]

What does NIP stand for? I googled it and got explanations ranging from Ethnic slur on Japanese to a portion of human anatomy. PWUTMA (Perhaps we use too many abbreviations) ?

[Steve Doerr]

Norfolk Island Pine

[John K Jordan]

I haven't turned that particular wood (and even if I had your pieces might be different) but I've had the best luck with the end grain on several other species by following the gouge with a negative rake scraper sharpened to about 60 deg included angle with a small burnished burr. I sharpen these somewhat like you might sharpen a skew, in fact, sometimes I use a small skew as a NRS. These are my favorites:

scrapers_neg_rake.jpg

Did you dry thinning the shellac first? I usually douse with shellac sanding sealer (already thinned) and thin it again for the first coat, dry completely (takes a few hours) then use a second or third coat with the unthinned sanding sealer. I have also had good luck with lacquer-based sanding sealer, also thinned for the first coat.

I assume the gouge is shaving sharp and the cuts are very light. I often get better results from a Hunter Hercules tool with very light bevel-rubbing cuts.

JKJ

[Steve Doerr]

John, the shellac I used was the sanding sealer version. However, I did not thin it but did put on several coats and let it soak in. Probably should have waited longer before taking my cuts. I also need to work on taking lighter cuts. When I would take the heavy cuts, it would really produce some large tear out.
Thanks.

[John K Jordan]

John, the shellac I used was the sanding sealer version. However, I did not thin it but did put on several coats and let it soak in. Probably should have waited longer before taking my cuts. I also need to work on taking lighter cuts. When I would take the heavy cuts, it would really produce some large tear out.
Thanks.

I like the term Chris Ramsey (cowboy hat guy) uses: "whisper cuts". Wood prone to tearout needs cuts so delicate that the shavings float suspended in the air! Besides a sharp/sharp/sharp gouge (or Hunter tool), a good NRS with a proper burr will also make whisper cuts on most woods.

BTW, for the sharpest gouges I use a 600 or 1200 grit CBN wheel and hone and even polish the edge - I get the best edge by stropping on the resawn surface of a piece of MDF coated with buffing compound.

I like to let the shellac dry until I can barely smell it.

I forgot to mention, on wood that gives me too much grief I sometimes resort to stabilizing with thin CA glue. I put a little on the wood and wipe it immediately with a small piece of paper towel, wiping with the grain (or figure) to blend so a CA "stain" in that area is not noticeable. A couple of applications of CA will almost always banish the evil tearout demon even in very soft/punky wood! Also, I'm sure you and 98% of turners know this, but turning "downhill" is important.

JKJ

[Reed Gray]

Since you are turning end grain, finish cuts should be, on the inside, a pull cut from the bottom up to the rim. On the outside, you should be pushing from the rim to the bottom. This is to follow the grain orientation. I prefer a shear scrape for this, and I use scrapers for that. Pretty difficult to do a shear scrape with a gouge on the inside of a bowl...

robo hippy

[Kyle Iwamoto]

Dry NIP? Tough. As Robo says, sheer scrape on the outside. Negative rake scraper on the inside. Water helps. You NIP is nicely spalted, and punkiness may have started. NIP goes from spalt to rot quickly.
I sand. Since I actually have no skills in turning.
You may have Cook Island Pine. A close relative. Difference being that that "growth ring" you mention is a CIP characteristic, and the eye knots on NIP are in a plane, this one looks like it is in a whorl, or spiral, another characteristic of CIP.

[robert baccus]

NIP is a very soft weak wood that is very chippy when very dry. I try to cut these when they are still a bit green (15%) maybe. All the above advice is good but I use lacquers as they dry much faster than shellac products. My go to for bitchy wood is a honed, scary sharp, 3/8" short beveled bowl gouge slowly advanced against an "edge".

[BILL DONAHUE]

I've worked with NIP quite a bit and had an article published in Woodturning Design several years ago titled "Translucent Norfolk Island Pine." It included a section about using liquid detergent to soak roughly turned NIP. After a 24 hour soak and then letting it dry, the NIP will turn much easier, almost like green wood. The technique can be found on the site of Ron Kent, one of the best turners of all time. Best of luck.

[Steve Doerr]

Thanks everyone for your advise and help in how to eliminate tear out in NIP. There is a lot good information in this thread, all of which is very good. I pick out a couple pieces of information that were extremely helpful in correcting the problem. The first one was that I was cutting in the wrong direction. Cutting from the bottom to the rim on edge grain was very helpful. As I thought about it, it was obvious that the way I was originally cutting was not getting the support for for the fibers that I needed. The second one was using the Hunter tool. It made all the difference in the world. I did a little experimenting and tried several different gouges but found that none of them compared to the quality of cut that I got from the Hunter.

Thanks again, appreciated everyone's help.