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GENERAL DISCUSSIONS => Building Materials => Topic started by: ear3 on May 31, 2017, 10:04 AM

Title: Edging material for douglas fir plywood
Post by: ear3 on May 31, 2017, 10:04 AM
I've been commissioned to build a large bunk bed assembly.  The client has a very particular vision that involves the use of douglas fir plywood as the principle sheathing/cladding material.  The plywood edges will be hidden for the most part, but there's one element -- a platform bed on the ground level (to be constructed essentially as a large mitered box) where the plywood edges along the top of the box will be exposed, and will therefore require some sort of cap. 

My question is what would be the best wood to use for that edging -- one that comes reasonably close to matching the douglas fir in color and/or grain, but is durable enough so that it won't dent/chip with the slightest bump (pine would be too soft IMHO)?  The unit will be finished with a stain, so absolute color match is not a requirement -- but I do want something that doesn't create too rough a transition between the plywood and the cap.  The unit will be finished with a stain, so that gives me some leeway on any color discrepancy.

Off the top of my head I was thinking about experimenting with Red Oak, Ash and Birch.
Title: Re: Edging material for douglas fir plywood
Post by: tjbnwi on May 31, 2017, 10:46 AM
If the doug fir is straight grained, QSWO T&G'd to the plywood. Or going the other way with Sapele.

Tom
Title: Re: Edging material for douglas fir plywood
Post by: Michael Kellough on May 31, 2017, 10:49 AM
Rotary cut DF ply has extremely variable figure from somewhat like plain sawn oak to psychedelic patterns. It will help if you can select the ply piece by piece.

The construction grade 2x material sold in our area is usually Doug Fir. It won't be dry (unless you go through the stack and find some old stuff) but since you'll be ripping it down (and ideally quarter sawing it so you'll more likely have late growth protecting the edges) it might dry fast enough.

Otherwise (unless you can order some dry DF) I'd use white oak. Similar figure to red oak (and ash) but less porous. Birch figure is too subtle.
Title: Re: Edging material for douglas fir plywood
Post by: clark_fork on May 31, 2017, 12:51 PM
Consider edge banding. This one is 250'.  Smaller quantities are available and some have no pre-glue if you want to use a strong epoxy if there is a heavy use concern.

http://www.oakwoodveneer.com/fir-edgebanding-douglas.html

Additionally, the maximum width of 18 mm/ 3/4 plywood is about 36' to avoid sagging. You may have to think about battens to keep surfaces flat and straight  if the runs are wider than 36".

Title: Re: Edging material for douglas fir plywood
Post by: ear3 on May 31, 2017, 01:33 PM
Thanks -- the 4 sided mitred box will actually be on its side/edges (like an open casket), so no weight is going on the actual ply, and there will be an internal structure on which the slats/sheets for the bed actually sit.  The design also involves making the box sides 1 1/4" thick, so I'm laminating 3/4 and 1/2 marine grade doug fir ply to achieve that -- but that means I have to use true hardwood for the caps rather than edge banding.

Thanks for the other comments -- I'll add white oak, both plain and quarter sawn, to the experiments. 

Consider edge banding. This one is 250'.  Smaller quantities are available and some have no pre-glue if you want to use a strong epoxy if there is a heavy use concern.

http://www.oakwoodveneer.com/fir-edgebanding-douglas.html

Additionally, the maximum width of 18 mm/ 3/4 plywood is about 36' to avoid sagging. You may have to think about battens to keep surfaces flat and straight  if the runs are wider than 36".
Title: Re: Edging material for douglas fir plywood
Post by: Joseph C on June 11, 2017, 01:55 PM
We have a lot of clients in this area that like to use ABX marine plywood (rotary fir).  With this material I use a lightweight wood filler to fill pores in the exposed edges and simply sand smooth - the aesthetic is raw.

one thing to be careful with is that the cut edges tend to flake up - put a 1/16 chamfer or roundover on right away, and be prepared for fun splinters and a little cussing.
Title: Re: Edging material for douglas fir plywood
Post by: ear3 on June 11, 2017, 03:25 PM
Thanks.  I've ended up going with ash.  Getting reading to flush trim the edging right now.

We have a lot of clients in this area that like to use ABX marine plywood (rotary fir).  With this material I use a lightweight wood filler to fill pores in the exposed edges and simply sand smooth - the aesthetic is raw.

one thing to be careful with is that the cut edges tend to flake up - put a 1/16 chamfer or roundover on right away, and be prepared for fun splinters and a little cussing.