single surface vs. double surfsce planer

[Adam Grills]

I have been woodworking many years. Unitl now I have a question of what a purpose. What purpose does a double surface planer serve? Do you not have to joint a reference point first anyway?
Grillzy

[Jim Heagney]

Adam,

I assume your talking about a planer.

A planer will give you a surface that is parallel to the reference surface.

Yes, you still need to joint one face or create one flat surface before you try to run the second side through the planer.

HTH,

Jim

[keith ouellette]

Its my understanding that a double surface planner is also called a molder. It makes both sides smooth and leaves the wood a determined thickness but does not do what a jointer does. Only an off set table can flatten the side of a piece of wood.

[Jim Heagney]

Looks like I'm the one that doesn't understand. Sorry for the wrong response. I have no knowledge of a Double surface planer.

Jim

[J.R. Rutter]

A double sided planer is what mills and lumber dealers use to plane both sides of a board in a single pass. The bigger/better machines have a jointer type infeed to do some flattening followed by a planer type head to make the top side parallel. They might even have a carpet type feed system with spring loaded fingers pushing the board over the jointer head. Entry level machines won't be capable of doing much flattening. Here's a link to one that has a video:

http://www.extremausa.com/planers_dsmagnum.php

Usually a moulder refers to a smaller capacity machine capable of shaping profiles other than straight and flat. Right now I'm shopping for a small 4-head moulder to run S4S as well as shaker groove rail/stile parts. Jointer type infeed, right side, left side, top planer head. This is the entry level for moulders and you really need 5 or more heads to efficiently run mouldings. Here's a video of the machine I'm leaning towards right now:

http://www.youtube.com/results?search_query=quattromat&search=Search