Replies

1. 
   Samson | May 27, 2009 04:59pm | #1

   A slight camber works fine for both applications.  In fact, some, like David Charlesworth contend that a slight camber is advantgeous for edge jointing as it allows you better control as you take down high sides and such.  Remember, the camber is really really slight.  It really just means that the shaving occurs at the middles of your blade first.  But you would be hard pressed to notice any scallop when looking or even checking with straight edges and feeler gauges.

1. 
   papiburrus | May 27, 2009 10:24pm | #4

   Thank you all very much for the responses, I'll hone the blade with a very slight camber and start practicing. 

   By the way, this was my first post/question despite a couple of years of reading the website/magazine.  Thanks also for the rapid responses.  Cheers!

   Edited 5/27/2009 3:26 pm ET by papeburrus

1. 
   Samson | May 27, 2009 11:57pm | #7

   Forgive me if you already know this, but I drew a quick picture as I feared the description in words seemed unclear.

   
2. 
   gdblake | May 28, 2009 01:55am | #8

   papeburrus:

   I want to second what Derek shared with you.  Match planing boards requires an iron that is straight across, no camber.  To match plane two boards, you put their faces together in the vise and line up the edges to be joined so that you plane the edges of both boards at the same time.  Any lean will be cancelled out by making the edges mirror images of each other. 

   If your plane is not wide enough to dress both boards at the same time, then a slight cambered iron will aid you in planing both boards to have edges that are 90 degrees to the face as others have told you.

   gdblake

2. 
   RRusso | May 27, 2009 06:05pm | #2

   Ditto what Samson wrote. You don't need a separate blade, and you definitely should not buy another of the same tool. Since you're just starting out, use that money to add to your basic set. You haven't mentioned what else you have, so I won't make recommendations.

   Regarding the main topic of the camber of the blade...

   I don't know of a "proper" camber, at least not in terms of the radius. When "properly" (for lack of a better term) rounded, it's not very noticeable when viewed alone, and barely noticeable when held against a flat surface with a light source behind.

   Samson mentioned David Charlesworth in his post. I highly recommend his books and/or DVD's. I worked for years before knowing who he was (is). After reading his books and watching his videos, I've changed many of my (bad?) habits and methods of work. For starters, I'd recommend his sharpening and hand planing videos. They're available through Lie-Nielsen's website (probably through David's website as well), and possibly through Woodcraft (not sure though). When you look at it with a training viewpoint, I think you'd be hard pressed to find a better bang-for-your-buck value. I'm not associated with L-N, Woodcraft, nor Mr. Charlesworth, btw.

3. 
   flairwoodworks | May 27, 2009 06:24pm | #3

   While as the other posters suggested, a slight camber will work for both purposes, if you don't like that idea, you could simply lightly radius the corners. That would eliminate plane tracks and still provide you with a flat surface.

   Chris @ www.flairwoodwork.spaces.live.com
   and now www.flairwoodworks.com)

    - Success is not the key to happiness.  Happiness is the key to success.  If you love what you are doing, you will be successful. - Albert Schweitzer

4. 
   derekcohen | May 27, 2009 11:10pm | #5

   I will go against the current stream and argue that you need two blades.

   One blade with a slight camber to effectively turn the jointer into a panel plane (i.e. a long smoother). This is for flattening wide boards, such as for a table top.

   The cambered blade may also be used to edge joint boards (ala David Charlesworth ... although I believe he may argue for a slightly greater degree of camber in a jointer than one used for a smoother).

   The second blade needs a straight/flat edge if you plan to match plane boards. You cannot do this with a cambered edge.

   Regards from Perth

   Derek

1. 
   philip | May 28, 2009 10:35am | #10

   Derek,
   "The second blade needs a straight/flat edge if you plan to match plane boards. You cannot do this with a cambered edge"
   Actually you can, but it merely introduces another slight complication for a beginner.
   I would advise Papeburrus to get another blade and see which he prefers.These blades are cheap-even free at times, so it would be a cheap lesson learned on the fly.
   I prefer to edge joint with a straight blade with equal projection then I can concentrate on where material needs to come off and not which part of the blade I am to use.Philip Marcou

5. 
   Samson | May 27, 2009 11:37pm | #6

   Just to further clarify in light of Derek's post.  Typically, when used to true up the face (flatten) wide boards or panels, the 7 is not intended as the last plane to touch the piece - i.e., a jack or at least a smoother follow.  As such, camber, to the extent is bing used to avoid plane tracks is not really even necessary.  I introduce camber on my bevel down blades just by a few extra strokes with appropriate finger pressure placement as I work the blade on my waterstones.  A few extra passes as the blades extremeswill make a minute camber.  I like how this makes my blades shave, but the plane would work for the flattening, jointing, and match planing operations pretty much the same with a dead straight grind.  In short, you don't need to obsess about this. 

6. 
   TMitchell | May 28, 2009 06:00am | #9

   Since the post was started with the expectation that you are beginning, I'll propose a simple decision point you can use to get you moving in A (not THE) right direction until you gain enough experience to know when all the other approches apply.

   Decide if you are going to A) use this for smoothing a large surface or B) for jointing two boards at once that will be glued together to create a larger panel.  I wouldn't expect a beginner to do more than just cleaning up a machined edge of a board not mating to another similar one, and this simple clean up of single edges can really be done with either flat or cambered blades. 

   A) If you are going to smooth surfaces, put in a slight camber to avoid track marks as you work across your surface.

   B) If you are going to joint two long-ish boards at the same time sharpen the blade straight and use it for that purpose. 

   For a beginner, I wouldn't recommend trying to joint a single board edge without any machine to first get it square and true.  If you were to go native on a piece of wood and do it all by hand then you do really need a cambered blade to finish the job as mentioned in the post above. 

   In reality I keep my #7 ground square for jointing two long edges at once so I can create a slight spring (this is a great trick that is worth another post/thread).  I keep my #5 and #4 with a camber.

   My #5 has a more aggressive camber and is set for a heavier cut for flattening boards larger than my jointer before running them through the planer (another well documented process in FWW and probably various threads on this board).  Basically using it as a Jack.

   Finally, my #4 is set with a camber so slight, you’d be had pressed to notice it without very close examination, and the slightest blade projection I can get.  I use this for removing machine marks before final sanding.  Basically using it as a traditional smoother.

   Honestly, of the top of my head, I can't remember the last time I did more than a quick clean-up pass or two to get a nice jointed edge (assuming it wasn't going to be edge-glued to another).  Most often, single edges are going in a floating frame groove or exposed completely with some profile and chamfered corners.  In this situation it will be virtually impossible to tell if the blade were straight vs. cambered blade once final sanding is done.

   Bottom line, make one good and simple decision at a time and you can't go wrong.

     - Terry

    

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   Edited 5/27/2009 11:09 pm ET by TMitchell

   
   

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   Edited 5/27/2009 11:12 pm ET by TMitchell