Minimum thickness on a planer

[Countryside Workshop]

I have a steel city 13" planer with helical head. What is the general rule of thumb on the minimum thickness I can plane down to?

I have a 9" wide board that I want to plane down to ⅛".

[Janello]

It should be stated in the manufacturers manual for that planer. If you don't have it, you should be able to find it online searching that model. That said, there is another way to find out. Stand clear (AS YOU SHOULD ANYWAY) and let it rip!

[Jfitz]

+1 on read the manual. My dewalt can go down to 1/8" but yours might be different. You could also run the board through on a thicker base (like a length of MDF) if the planer cannot go that low but you need to be careful about the board getting so thin that it falls apart.

[TerryMcK]

Mine goes down to around 3/16". You really have to watch what you are doing on those thickness's though as you can end up with just a pile of splinters on some species.

I normally use double sided tape and stick the stock to a backer board. That way you do gain a little support from the backer providing the adhesive is strong enough. Then you have to try and prise it off the backer without breaking it. Been there done that!

 

Ahh just read that's what John said.

 

+1 on what John said 

[wdwerker]

+2 on backer board w double face tape. Don't get carried away with the tape, use segments not continuous . Just enough to stop rattle and slipping. Slide a putty kinfe under carefully to remove.

[RPCV_Woodworker]

If the manual says you can't go that thin, you could always make a sled to raise the wood.  Raising the material effectively makes it so that you can bring the head down to whatever thickness you want without bottoming out your adjustments.

 

That being said, not all woods are a good idea to plane thinner than 1/8".  If it has any figure, tearout could destroy the board. I know you have a helical head, but I'd still be worried about a board that thin chattering and breaking up in the planer, even with double sided tape and a sled. I go down to 1/8" on my Dewalt, but only on nice flat long-grained boards. I had some poplar with a spot of curl in it once, and the shorter grain blew out and ruined the piece.

 

Ideally, I'd go find someone with a drum sander instead.

[Brendon_t]

I feel that using only increments of tape would depress the not taped dost under the roller pressure and push the other part up getting an uneven thickness across the length.