Thread: Smoothing with a Low Angle Jack

Hi Andy
You're on the right trail. Imagin trying to "level" a football field with a rake, you can easily get it smooth but you will have some hills and hollows (if it rails you get mountains and lakes. The rake is your smoother!
If you "level" your footy field with a tracktor with a wide blade its going to be way better and the hills and lakes will be smaller. Thats your Jack (LA or otherwise).
If you level it with a ground plane (realy wide lump of steel towed behind a tracktor then you will get it realy level, no hills or lakes. Thats your jointer (6,7 or 8).
The blade angle just stops tearout etc
Hope that helps put things in perspective. On a table top or door etc I start with my jointer then LAJ and then smoother, often the jointer does the lot, depends on timber type and how cranky the grain is.
Good luck

PS if its cranky then the last step is the scraper plane or hand scraper.

Andy

The thing is that wood moves, and then it is not as flat as it might have been even only a couple of hours before.

Regards from Perth

Derek

Thanks for the replies

I'm still a little confused to why a smoother will create a better finish than a LAJ with the same irons?

I'm very painful arnt I ?

I get your confusion ! Perhaps the texture/roughness of the timber wont be any different but the longer plane will produce less highs and lows ?

If the surface is level I don't think it will make any difference as long as the mouth on your jack or jointer is closed up to a similar mouth as your smoother.
Maybe this is the diff between a normal jack etc to a LA's, you get the added benifit of an adjustable mouth.

The surface only appears level and flat. In reality it is not.

Both have to get to the valley. A long jointer will be forced to ride the peaks, and have to remove more wood to smooth the bottom of the valley than a short smoother.

Both can smooth a board, but a jointer requires a flatter surface than a smoother to do so.



Once the board is "flat", both planes could conceivably do as good a job as the other. The smoother is preferred to the jointer for this purpose since it is more efficient. Further, smoothers being dedicated to smoothing are often built with just that purpose in mind, so they can offer a preferred cutting angle, while the jointer more often tends to be oriented to flattening, and the cutting angle is less an issue.

Regards from Perth

Derek

It's making more sense...
Thanks for the diagram Derek

I beleive we are being confused between flat or true and smooth.
A smoother will give a better finish becaust the iron is at a greater angle. Your low angle plane is good for end grain but it is possibte for it to get under the grain and lift small pieces out.
Rowley.

Originally Posted by Rowley

I beleive we are being confused between flat or true and smooth.
A smoother will give a better finish becaust the iron is at a greater angle. Your low angle plane is good for end grain but it is possibte for it to get under the grain and lift small pieces out.
Rowley.

I got a 38 degree iron in my LAJ which is the same as a LA smoother.