Need dead flat on both faces... Jointer and planer? Do I really need a planer?

[Nick Sorenson]

I have a situation where I need both faces dead flat for machining. I have a planer and sold my jointer a year and a half ago. I make most joints with a table saw and get them as tight as can be with the proper jigs. So I haven't needed the jointer.

But now I'm having a hard time getting a dead flat surface. I would think I could put the peak of a cupped board facing the cutters in my planer and get rid of cupping but I'm not having too much luck. I really need my workpieces to be flat within around .010 (and with no rocking or cup at all) and there are times I'm not getting that. Do I need a jointer again?

[Matt Day]

Try doing a search on here for a "planer sled". There are lots of different versions and ways to make one, but I think it's your best bet without a jointer.

[Bill Huber]

I don't think you can get a cupped board flat in a planner with out using a sled. If the board has a cup to it the rollers will push it down and then when it comes out from under the rollers it will cup again.

With a sled and spacers under the cup it could be done with light passes.

[Rod Sheridan]

Hi Nick, you either need a jointer (easiest and best) or you need a sled for your planer if you want flat material.

A planer only makes objects parallel, not flat or straight.

With a planer sled, you support the wood on little adjustable wedges to hold it in a fixed position as it goes through the planer. This will make things straight, however it's laborious as you have to adjust the sled for each work piece.

With a sled, you also can't edge joint material so you'll need another work around for that.

If you have the space, get a jointer.............Regards, Rod.

[Mike Schuch]

It's a terminology problem. A planer isn't really a planer a planer is REALLY a thicknesser! A jointer is really a planer... it makes a flat plane on a work piece. I don't know how you can do any serious woodworking without a jointer? My $180 6" HF jointer is the second most used machine in my shop and the first machine to be used when starting any project.

You kind of need both machines. A jointer will give you a very flat plane. You can use a jointer to get a flat plane on each side of a board but there is no guarantee the two planes will be coplaner (parallel to each other). You need a planer to get two parallel (coplaner) sides.

A planer sled is an option if you are into a lot of extra work and hassle.

[Chris Padilla]

Mike,

You must be from Europe! That is how they define those pieces of equipment.

As long as one understand what each piece of equipment can do, there should be no problem.

[Nick Sorenson]

space is the main issue for me but sounds like I'll just have to put in a walkway over the planer;)... lol. I may have to bite the bullet and get another planer. But I'll try the jig method first and see how it goes.
Thanks guys!
Great advice as always.

[Erik Christensen]

when it comes to getting a flat surface on the face of a board I find I am using my drum sander more often as time goes on - mainly because it takes a fair amount of skill to use a jointer to flatten a large board and even with a helical head there is usually some tearout so it has to go through the sander anyway so I just toss it through a few extra times and skip the jointer step

[pat warner]

A note on flatness. .010", tho modest whether cup, twist or bow, is enough rock & roll to spoil precision machine joinery. No so for the hand cutters, but jigs/fixtures etc. that see a 10 mil error can't register the same board twice in the same place!
Morover, without granite sanding or hand planing after thicknessing your work, tho perhaps uniform in thickness, may well be cupped or mishapen.
What I'm saying here is don't get crazy about flatness & thickness unless your whole train of tooling (http://patwarner.com/material_prep.html) and machinery is also to that accuracy. E.g., no need to flatten or edge stock to .010" if the next thing it sees can't recognize it.

[glenn bradley]

+1 on planer sled (http://www.finewoodworking.com/SkillsAndTechniques/SkillsAndTechniquesPDF.aspx?id=24118).

[jonathan eagle]

It's a terminology problem. A planer isn't really a planer a planer is REALLY a thicknesser! A jointer is really a planer... it makes a flat plane on a work piece. I don't know how you can do any serious woodworking without a jointer? My $180 6" HF jointer is the second most used machine in my shop and the first machine to be used when starting any project.

You kind of need both machines. A jointer will give you a very flat plane. You can use a jointer to get a flat plane on each side of a board but there is no guarantee the two planes will be coplaner (parallel to each other). You need a planer to get two parallel (coplaner) sides.

A planer sled is an option if you are into a lot of extra work and hassle.

Mike, Very articulate way to describe the problem.

[Andrew Joiner]

Most sleds are heavy and complicated. A thin light sled will work with simple rough cut wood shims. On 8/4 stock I use 2 shims at each end for sure, but it usually just takes 3 or 4 more toward the middle of the board to get flat faces. Almost as fast as a jointer and with power feed!

I have an 8' sled. I used one layer of 3/4"plywood 8'x 13" for the sled. I have an infeed table that is flat and parallel with the planer table to set up the shims. This is the key thing for a thin sled. You could even use a 1/4" thick sled once you get the technique down.
Here's the link http://www.sawmillcreek.org/showthread.php?t=134633

[Curt Harms]

space is the main issue for me but sounds like I'll just have to put in a walkway over the planer;)... lol. I may have to bite the bullet and get another planer. But I'll try the jig method first and see how it goes.
Thanks guys!
Great advice as always.

Nick, you're not alone with space being an issue. That's one of the primary reasons to get a jointer/planer combo machine. A space 2' X 5' gets me an induction motor powered 12" jointer & 12" planer. Yeah they're not cheap but neither are 12" jointers by themselves.