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David Myers
04-26-2009, 10:21 PM
I'm nearing the completion stage on a potting bench for my wife. Since I'm new to the neander way I'm using this project to work on some fundamentals.

So today's question(s):
When should I stop with the #5 and start with the #7 (how flat is 'good enough' for the jack)?

When should I transition from diagonal plane strokes to lengthwise ones?

Thanks in advance,
David

Fidel Fernandez
04-26-2009, 11:36 PM
Your first question:
When the side your are planning does not rock anymore. It must be flat, "good enough" is not enough in my opinion.

Second question:
I use diagonal planning when I test the wood with winding sticks (2 pieces of wood flat. Placed at opposite ends of a board, they accentuate any twist.) and I see one side is higher than the other (twist).

When there is no twist then I use my jointer lengthwise, and when is flat, I finish it with my new LV LA BU Jack Plane.

I can tell you this works. I finished this weekend my workbench top (flatten out) and prepared the jaws (ash wood) for my vise with that technique and it works.

A lot of work but I have a flat and level workbench, and I will install my vise tomorrow.

Danny Thompson
04-26-2009, 11:38 PM
Blind leading the blind, but I believe the answer to both questions is:

When you can take a full length shaving.

Others, chime in.

David Gendron
04-27-2009, 1:51 AM
What I do is i use the #5 to remove any bumps(hi spot) if there is no twist in the top. If there is twist then go from one corner to the other (hi corners) use your #7 for that since the sole is longer it wont follow the low spots as easely! go back to #5 and remove all hi spots usualy working across the top(traversing)keep track of your progress with straight edge and when it look some what flat you switch to your #7 and go with the grain to remove all the scalops made by the crown blade of your jack plane and then if you realy want flat, get your #7 realy sharp and take some nice long shaving and finish with tin shaving to get you final finish!
that sond like a long process but it fster than you think!
How big is the top? What is the wood?

phil harold
04-27-2009, 2:12 AM
it is a potting bench?
one that is going to be used for potting plants?
one that is kept outside in the elments or in a shed contact with water, potting soil and fertilizer?

or

is this a potting bench that is a piece of furniture?

RickT Harding
04-27-2009, 8:35 AM
I've been working hard on flattening my first tabletop by hand tools. I've had to do it a couple of times because I didn't go far enough with the jack before moving to the jointer and then it was taking forever.

I'm with Danny, keep going until you get full length shavings. When I finally got it working I started out with the jack going across the boards, then diagonal, and finally with the grin across the boards.

David Myers
04-27-2009, 11:46 AM
Thanks for ther responses.

To answer a few questions:

1) The top is made from cedar, about 20 inches wide by 5 feet long.

2) Yes its going to live outside; it was flat enough for its final use after the initial glue up; I'm doing this to learn how to flatten large surfaces in preparation for a real workbench hopefully later this year.

Fidel Fernandez
04-27-2009, 11:56 AM
IF you have a chance to get a scrub plane for you next task, I would recommend it. It will make your life easier.
I use the scrub plane as my first plane, to make the piece flat. It will make you work less and will save you time. Its rounded blade and light weight makes it easier to handle, even with one hand.

I follow with my jointer and LA Jack plane or smoother.

David Keller NC
04-27-2009, 12:12 PM
"Yes its going to live outside; it was flat enough for its final use after the initial glue up; I'm doing this to learn how to flatten large surfaces in preparation for a real workbench hopefully later this year."

Regardless of how flat you get this now, it won't be after just a little while outdoors, but your thought makes sense - it's good practice for flattening large panels.

I can offer a couple of tips; the first one is important:

1) Use penciled scribbles to show you where you're planing. It's very, very easy to cut a hollow in either the width or length on a big panel if you don't do this, because it's really easy to overlap strokes to the point where more is removed in the middle (either width or length) than on the edges. Once you make a pass with the jointer, scribble all over the top again, regardless of whether your last pass removed all of the previous scribble marks. Don't make a complete pass, then go back and make a couple of more strokes on the part that still has scribbles - that will take you farther away from your goal of a flat top, not closer.

2) Use the side corner of your jointer plane to assess the flatness of the top as you go - they make excellent straightedges to show you the condition of the top. However, don't make the mistake of assuming the top's way out of flat based on just the fact that you can see daylight between the edge of the plane and the top - just one or two thousandths is more than enough to look like a large gap, and trying to get it absolutely perfect over the entire width/length will be difficult - you're shooting for flat within about 5 thousandths over the width, and about 10 thousandths over the length.

3) I think you've already discovered this, but heavily chamfer the edges before you start. Cedar's really brittle, and will "spelt" badly on the edges when the plane's run horizontally across the grain.