Larger Picture Frame Backing Options

[PittTrack]

Over the past few years I have made various picture frames.  Generally I make the 8x10 ones (and smaller) not as deep but the 11x14 and 16x20s usually are made thicker.  I've made 16x20s in the past and used 3/16 foam board for the backing of those as the frame thickness is usually around 1.125 to 1.375 thick.  This allows me to get the frame to lay flat on the wall and still look good.  Typically I use turn buttons (recessed) and some D-rings which take up some space.  Anyway this year I decided to forego the router table and went with a simple yet elegant approach which caused the depth off the wall to be a mere 3/4".  I am going with a 1/4" setback from the front before I start the rabbit.  Add the glass and the back and it could get to where I don't have room to hang it w/out it leaning away from the wall.  I'd like to not cut keyholes in the back as I usually don't use Hangman double-headed bear claw hangers but generally use the hooks that get toenailed to the drywall.  


For my smaller size frames I use a thin yet strong back (some have legs, others don't) as shown here https://craft-inc.com/collections/easel-...-x-14-back but unfortunately they don't make the backs in a larger size than 11x14.  I've looked all around and anything thin that I found was thin mentioned also doubling as mat board which leads me to believe it's not too strong.  I've toyed using 1/8 hardboard available at HD/Lowes but wanted to see what else I could source (exp if it's as thin as the backs I mentioned)

Thanks for any insight that you can provide.

[Cooler]

I used to be a picture framer and having the images tilt a bit did not bother me.  Larger pictures are generally hung higher and the modest tilt is an advantage. 

I would not use wood for a backer as the lignins in the wood are harmful to most art.  A PH neutral backer board is much preferred.  These are generally marketed as "archival".

[FS7]

For what it's worth over the years I've never used anything besides 1/8" tempered hardboard commonly available at the big box stores. I only use them for printed photos, not paintings or anything, but I've never had any sort of problem with that approach. Easy enough to make whatever size you need.

[MichaelMouse]

I used to be a picture framer and having the images tilt a bit did not bother me.  Larger pictures are generally hung higher and the modest tilt is an advantage. 

I would not use wood for a backer as the lignins in the wood are harmful to most art.  A PH neutral backer board is much preferred.  These are generally marketed as "archival".

Well, you can easily isolate the wood from the art by using an impervious acid-free backer.  FWIW, though I will NEVER again admit I can make frames among those needing them, you don't need a full backing, a ~3/8 X 3" stiffener in the lengthwise dimension seems to work for 2-3 feet distance keeping things aligned.  

Little shellac wouldn't hurt, either.

[Cooler]

Really large frames with small profile mouldings can be an issue.  The horizontal frame members can bow under the weight.  For those, I would glue up a mat board to keep things straight.

I would follow up with a dust cover made from craft paper glued to the back of the mouldings.  I used adhesive transfer tape for that. 

A light misting of the dust cover with a light wipe down with paper towels will leave the dust cover uniformly wet.  As it dries it will shrink and leave a drum-tight and very tidy appearance.  It looks "professional" and makes a nicer package especially if it is a gift.

[OldGuyDrummer]

For decades I would build picture frames the classic way, heavy/thick around the outside, thinner/lighting around the inside. 
About a dozen years ago I flipped the profiles, thinner outside, thicker inside and it significantly reduced the weight of the frames. 
Have never had issues with bending/warping. 

I just use matted boards for framing picture and backing. The largest picture frame to date was 24"x36". All the miters are reinforced with small dominos. 

   

   

[Cooler]

I framed several thousand pictures and the only miters to give me an issue were the ones over 2-1/2" wide moldings.  The seasonal movement would eventually work the joint loose.  We used an underpinner so this rarely became an issue as the underpinner provided a mechanical fastener. 

Certainly wide moldings are subject to miter failure.  Much less once we went from white glue to Corner Weld (a very fast setting version of Tight-bond.  I recently tested the strenght of Corner Weld vs Tightbond III and found them to be about equal for miters.  The Corner Weld would start to setup in under a minute, so it could be handled in a couple of hours.  Other than that I see no advantage.  But it was a huge leap forward over white glue, which was the industry standard up until that time.

If you do the math on a 3" wide molding you will see that the inside will be 6" shorter than the outside of the miter.  T

Basswood is the most common wood for most pre-finished mouldings.  I don't know the expansion rate for that specific species.  But it is enough that a 3" wide molding can pop the glue joint.

[fredhargis]

It's not my favorite, but I've been using the 1/8" tempered hardboard. It works well, the thing I don't like s the weight. So I was looking at the place where I get my Matboards made, and they have all manner of backing boards. If you feel you want to go pro, take a look at this stuff. My frames have mostly been less than 20" in any direction, almost certainly if I make a larger one for some reason I'll try the other stuff.

[John Mihich]

2 things.  I use 1/8 hardboard and then I use brown paper that I glue to the frame on the back.  It's easy to do and adds rigidity to the frame.  This is what pro's do.  I have a friend that did this for a living and he showed me.  Just PVA glue and brown paper.

[Stwood_]

Brown paper.......