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  1. #1
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    How to reduce tearout when planing?

    I am in the process of laminating 3/4 inch Ash boards (various lengths) into a bowling alley style bech top. There is no way to keep the grain running all the same direction, although I will try and do my best to get most of it one direction. I need help on how to flatten it. What tools to use etc. Initial cutting shows I will run into trouble without help. Maybe I should just take it in and get it sanded after I rough it out. Cutting across the grain is even starting to worry me. Which plane would work best? Thanks for your help and ideas.

  2. #2
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    Pat, wide glue-ups are always problematic to flatten, short of running them through a widebelt sander. Any knife-type planer, even if wide enough, will cause some tearout against the grain. Even spiral-head planers are usually 20" wide or less.

    A router attached to a sturdy "sliding bridge" can be mounted atop straight-edged boards on either side of your slab, and used to make repetitive cuts back and forth to level the top. It is basically like screeding a concrete walkway. The going is slow, but it is low-tech and it works. A ROS can then smooth out your router marks. Here's an old how-to:

    Rouer levelling Jig.jpg

    For hand plane solutions, you will have to ask over at Neanderthal-Haven.
    Necessisity is the Mother of Invention, But If it Ain't Broke don't Fix It !!

  3. #3
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    I'm running into the same problem with QS ash..the reversing grain within each board makes it almost impossible to plane without tearout. Once I use up what ash I have I don't think I'll ever use it again

  4. #4
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    Depending on how much material you have to take off you could always hand plane using a #7 or #8. Just make sure that you appropriately sharpen the blade using a micro bevel at say 5 deg if you are using a standard angle frog or pick up a HAF. I am jointing/planing maple tops for two benches right now and with straight blades in a machine they need to be brand new and sharp and that is still no guarentee. At least when you use a jointing plane you have more control and can make a decision to stop if you are not getting the result you want with a couple pushes. Once you start feeding the slab through a machine it is tough to make the decision to stop. You could take to to a cabinet shop and they may have a large spiral head in their planer but it is just as important that they have one in their jointer.

  5. #5
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    Just out of curiosity Pat, have you tried planing it by hand with a well-tuned and newly-sharpened #7 or are you just getting your information gathered before doing the actual work?

    I'm curious because I'm looking at doing a bench myself and I always assumed that a well-tuned hand plane would be just the ticket.

    Quote Originally Posted by Stephen Pereira View Post
    ...Once I use up what ash I have I don't think I'll ever use it again
    It would appear that this won't be a decision you'll have to make:

    Stop the beetle!

  6. #6
    I just did a project like this in cherry. I spent $50 to have a mill flatten it on the drum sander. WELL WORTH IT. Then I sanded.

    If you have new blades on a benchtop planer, you can do the slabs in 2 halves, run them thru the planer with really light passes, and then glue them back together.

    If you are determined to do this by hand, then you'll get best results with the sharpest possible blade. You will minimize tear out as you increase the cutting angle. A scraper or scraping plane or cabinet scraper can also give good results, albeit with more sweat equity. You can also try a toothed blade.

    Oh yeah, plane across grain for the initial flattening.

  7. #7
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    This is what I have used successfully for planing without tear-out:
    http://www.japanwoodworker.com/produ...&dept_id=13602

    It is the Mujingfang High Angle (62.5) Rosewod that tied for second in this well-known high angle plane comparison by Lyn Mangiameli.
    http://www.woodcentral.com/bparticles/haspc.pdf

    At $56 it is the only low cost new plane I recommend.

    If the board are not glued up yet I would also recommend test-planing each one on the exposed face to see which direction does not tear out and marking that direction with an arrow.
    Veni Vidi Vendi Vente! I came, I saw, I bought a large coffee!

  8. #8
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    Jan 2011
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    Drum Sander.

  9. #9
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    I'm reading up on the planes you suggested Brian. Maybe I will find a solution there - I don't have any planes nearly that steep of an angle. I am trying to check the grain on each piece before I glue it in place, but the trouble is the grain direction reverses in a piece then no matter what I end with some going the wrong way. First I need to get the boards approximately flush to each other. Is there some kind of across the grain technique that will work good enough to finish with a RAS?

  10. #10
    Going across the grain should virtually eliminate tearout. However, this won't flatten the table in lengthwise.

    You can use a belt sander to do the same thing. You just need to check your work more often than with a jointerplane, since the BS is more aggressive and has a smaller reference plane.

    If you can alternate the cups and bows and warps in yr individual strips, you might find (like I did) that they cancel each other out. That is, you might end up with a surprisingly flat end product that doesn't require too much flattening.

    Glue up the strips one-at-a-time so you can take lots of care to keep all the pieces close to flush. You can also scrape up squeezeout before it hardens.

  11. #11
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    Fine WW had a piece this month on using differing angle and toothed blades in a low angle jack plane to control tear out - Lee Valley, LN and the like sell them and they are not too expensive.

    As above you can also grind a micro bevel on the flat face of the blade normal bevel down hand plane, and also on power planers. Fine cuts also help.

    I've never done it, but David Charlesworth had a piece years ago in one of the UK mags where he described a method of grinding a very short 10-20 deg micro bevel on the leading/flat face of both hand and power planer blades.

    This he says can be dressed on to the blades in situ on most power planers using a slip stone wrapped in tape to protect the drum, but it increases the cutting force a bit.

    The methods for both power and hand planes are published with drawings on p. 39 in his soft cover Furniture Making Techniques, The Best from Furniture and Cabinet Making Magazine. 1999, ISBN1 86108 125 1 Published by The Guild of Master Craftsmen Publications Ltd. in the UK.

    It's probably available from Amazon and the like, but be careful as there are two subsequent books of his in the series in the same format, and with very similar titles.

  12. #12
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    In answer to Russell's question, I have done enough already as part of cleaning up between laminations to see that I am going to have significant problems with the tearout. Now keep in mind, I'm working in a garage shop inn MN and its been very cold - maybe the wood will behave better when its alll warmed up with my heater. I know my fingers were freezing when I was working on it and noticed the tearout.

    In answer to Mikes comments about using a #7 or #8 jointer plane, I have two planes that are fairly large to do the rough flattening with. One is an old No 5 Stanley/Bailey that I like a lot, but which I hate to abuse right now since I spent a lot of time learning how to sharpen the blade. The other is something similar but not quite as heavy duty, but one that I don't mind abusing . I''m wondering if I were to try and give a slight convex grind to the 2nd tool and use it across the grain as a first step - basically to knock the edges down on the boards that are not sitting perfectly with the others (slightly proud do to no straightness or clamping issues during glue up). I was reading that I should do this in a diagonal crosshatch sort of manner for best results. Then I would follow up with the No 5 to finish the smoothing process as best I could. Maybe at that point, could I turn the plane iron bevel side up to increase the attack angle and help reduce tearout when going lengthwise? I don't have access to a larger jointer style plane at this time.

    I'm going to check around with a couple local places to see if they willl run it thru their belt sander a couple times for me like Prashun suggested also - for $50, if thats what they would charge it might be the best way to go.

    I'm a little afraid this tearout problem is going to put a damper on all the work I have invested in salvaging material, planing, ripping, cutting to length and laminating one row at a time.

  13. #13
    Drum sanding is a sound approach. Just make sure that you sand carefully after it returns. The surface may appear nice and smoothly sanded to 100gt, but it'll likely have roller marks that won't appear until the finish starts to build (DAMHIKT...)

    As for abusing a wellsharpened blade, that's what it's for. You'll increase your chances of tearout (of the wood and your hair) if you try to use a substandard blade that hasn't been sharpened very well.

    I don't believe non-block style (or low angle) planes are supposed to be used with the blade bevel up.

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