Replies

1. 
   Midnight | Sep 20, 2005 10:05pm | #1

   Two questions: (a) Any thoughts on what the problem is, how to avoid it?

   It sounds like the grain's changing direction in the areas you're having probs with... Refer back to rule #1... always plane with the grain... It might help to increase the angle of attack on your blade; hone a 5 or even a 10 deg micro-bevel on the back of the blade. Alternativly switch to a card / cabinet scraper...

   Mike Wallace

   Stay safe....Have fun

2. 
   Willie | Sep 20, 2005 10:08pm | #2

   Houston,

   The text below is copied from Lee Valley's web site. This will solve your problem.

   If you wish to finish the table as is, you would either have to use a filler, or a self leveling epoxy.

   In a bench plane, the blade is used bevel down, so the bevel angle has no bearing on the cutting angle. This is determined by the angle of the bed which, in this case, is 45. In the past when steeper cutting angles were desired, particularly for smoothing, special planes were produced with bed angles of 50 or 55. However, the same net effect of altering the cutting angle can be achieved by introducing a back bevel on the face of the blade. In this way, a 5 back bevel will yield an effective cutting angle of 50 (commonly known as a York pitch). A back bevel of 15 will yield a cutting angle of 60 (see Figure 5); this will result in an entirely different cutting action from the standard 45, producing what is known as a Type II chip (or shaving) as opposed to a Type I (reference: The Complete Guide to Sharpening). With this type of chip the wood shaving fails right at the cutting edge, eliminating tear-out and enabling the working of difficult grain patterns. This type of cutting action is similar to that produced by a scraper. The higher cutting angle increases the force necessary to propel the plane and is not required when working with the grain. However, when you have to work wood with widely varying grain (e.g., birds-eye maple) its handy to have a back bevelled blade at hand. Changing blades has the same effect as using a high-pitch plane.

   We recommend a back bevel of 15 to 20 for most difficult planing situations, which yields a cutting angle from 60 to 65. Note that even within this range, there is a significant difference in how the plane performs. At 60, the plane will cut well against the grain, except around knots and the more dramatic grain swirls. Increasing the angle to 65 will all but eliminate tear-out, even around knots and rippled grain such as found in birds-eye or curly maple. The 5 increase will, however, make the plane noticeably more difficult to push. We therefore recommend beginning with a 15 back bevel to produce a 60 cutting angle, and only increase it by another 5 to 65 if you still experience tear-out. It is also important not to skew the plane in use when a back bevel is employed as described here as this has the effect of reducing the included angle.

1. 
   HoustonHeights | Sep 20, 2005 11:28pm | #5

   I am actually reading Lee's book on sharpening right now.  Looks like I'll get to put that knowledge to use right away.

   As for fillers and epoxies -- what do you all recommend?  What is the least visible, most finish compatible method?

1. 
   sapwood | Sep 20, 2005 11:44pm | #6

   You can fill with clear epoxy (I use 5 min. epoxy) or thick super-glue. Or finish then use filler sticks applied with a hot knife. Mohawk makes some that are very easy to use. The problem with tearout is the rough surface that can be still seen through the clear filler. I've been successful in hiding these by smoothing the void with a small carving gouge before filling. Use a satin sheen finish and the fills will blend right in.

3. 
   CajunDan | Sep 20, 2005 10:51pm | #3

   I had the same problem with an African Mahogany tabletop I was making. No matter what I tried, or how sharp the blade was it always tore out a little.

   That weekend was the Houston Woodworking show, where I asked the Lie-Nielsen demo rep how to plane figured mahogany. He demonstrated with their low-angle jack plane, and still got a little tear out. "Sometimes tear out is unavoidable, and you have to clean up with a scraper," he told me. So there you have from a pro.

   I am guessing by your name that you live here in Houston?

   Regards,

   Dan

1. 
   HoustonHeights | Sep 20, 2005 11:26pm | #4

   Thanks, I appreciate your response.  Looks like I've got some quality time with my scraper coming up. 

   Yes, I am in Houston.  I take it from your response that you are too.  Have you found any good woodworking clubs/groups in town? 

4. 
   Rich14 | Sep 20, 2005 11:46pm | #7

   Houston,

   "Two questions: (a) Any thoughts on what the problem is, how to avoid it?

   (b) Is there a way of filling the small tearout areas to achieve a smooth top that won't be blarringly obvious?"

   a) The "problem" is that there are situations and conditions where a steel blade, no matter how well sharpened, angled and otherwise "tuned" cannot shave the wood tissue cleanly and some tearout is inevitable.

   You can avoid the problem by avoiding the failed technique.

   A cabinet scraper correctly sharpened and bowed between the thumb and fingers is a joy to use in such situations. It takes a little experience to properly sharpen a scraper's edge and LN, among others sells all the equipment needed (the scraper itself and a hardened burnishing tool) and good descriptions how to do it. Once learned, it is very easy, and takes just a few seconds.

   Also, have you heard of sandpaper (sarcasm alert)? This will also do a beautiful job, used properly.

   b) No! Any "filler" you use will ultimately be visible as a departure from the surrounding wood texture and grain pattern. Which brings us back to either the scraper or sandpaper. You will need to bring all the surrounding wood down to the level of the deepest tear out in order to "remove" it. A cabinet scraper is best used to provide the final surface on wood already prepared by planing. It is not meant for heavy wood removal. But it is up to the task with lots of resharpening. Be prepared for fatigue in your thumb and hand muscles. And lots of HEAT!

   Sandpaper can also do the job. Start with VERY coarse and don't rule out using a belt sander. But a ROS will do a very good job. Get the entire top perfectly level and free of tear out holes with the coarsest grade FIRST. Then the rest is easy, using progressively finer grits to remove the scratch pattern of the previous until you're satisfied with the result.

   Rich

5. 
   jazzdogg | Sep 21, 2005 06:19am | #8

   HH,

   In addition to what others have already contributed, I'll add a recommendation that you wet-sand the top.

   I typically wet-sand with Liberon finishing oil, but it's the underlying premise that's important to understand: after you've scraped and sanded the surface fair and flat through 220-grit, wet-sanding will create a slurry of oil and sawdust that will pack the pores and areas of mild tearout. Since you're not introducing a foreign substance like epoxy, and you'll be wet-sanding the entire top, it will have a uniform luster and texture when you're done.

   I've attached a snapshot of a piece of wet-sanded African mahogany if you're interested.

   Good luck,

   -Jazzdogg-

   "Don't ask yourself what the world needs. Ask yourself what makes you come alive, and go do that, because what the world needs is people who have come alive." Gil Bailie

   
1. 
   philip | Sep 21, 2005 10:59am | #9

   Houston, Jazz got it in one.
   You can also get the same result by wet sanding using mineral turpentine-dries out chopchop so you can follow with a sealer like the Zinsser Bulls Eye de waxed shellac followed by whatever.Philip Marcou

1. 
   HoustonHeights | Sep 21, 2005 06:59pm | #10

   Thank you all very much for all the feedback and advice.  I'll post a follow-up message to let you all know what I did and how it turned out.