Need Refresher, All UltraConservationists


SGF, Supreme Grumble Framer
Founding Member
Jul 30, 1997
Leawood, Kansas USA
I'm doing the good stuff. Using BB Artcare Alpharag 4-ply, two mats, lining frame rabbet with Lineco tape, making sure it's far away from art, Nori hinging art, booking the mats. Mount to what, please?

I know we had a dust-up about needing to mount to Artcare, then back with Artcare foam. Am I correct in thinking we don't mount directly to Artcare backer? and if so, why?

So sorry they didn't want Museum glass: CC just isn't as gorgeous, but...
Artcare foamcore or Artcare Alpharag?
Both products are in BB's Artcare line...just means that the Zeolites are present.
I believe that tradition holds that the mount should be to 4 or 8-ply ragboard (depending on size). The support board has traditionally been acid free corrugated (the blue stuff). With the introduction if substrates such as Ployflute and the various foam centered boards, there have been greater choices of better products which have muddied the waters somewhat.
When I do a "Museum" mount, I hinge to ragboard and back with polyflute. For items that don't need that high a degree of conservation, but the client still wants an archival environment, I will hinge to BB acid free (Artcare) foam board. Tradition may be the greatest influence in my decision making, that and hedging against future studies showing that long term degradation of the foam in foam core is damamging to artwork.CYA.
I'm either hinging to Artcare Alpharag or Artcare foamboard. And since I'm giving this the royal treatment, I guess I'll hinge to the Alpharag and back with another Alpharag. These are small enough that the backer of rag is strong enough. (unless someone doesn't think so.)

I just remember a big discussion that the mount board of alpharag and then a backer of alphafoam was overkill....and some of the posters were the knowledge base we all love.
The advantage to polyflute as a support is that it is unaffected by changes in humidity (ahygroscopic?), is less gas permeable than the other options, and can act as a vibration dampener (transit).
yes. Coroplast is a brand name for fluted polypropylene. aka polyflute, aka corrugated plastic.
it's about time Orton checked in here again.
Something tells me he doesn't have time to read the G.
It's been so long since Orton was here that his last post is in the archives!! I went looking for him and found the last post to be way back when Ron and Markg1 and I took the imfamous road trip to Atlanta and I commented on the ASAP tapes that we bought. Orton had run some tests on them but never got back to tell us what the results were.

BTW, I still use their ATG tape and still think it's the best for holding together matboards and installing dust covers. It just never seems to let go!

My understanding is that you would hinge to matboard because the way it expands or contracts with changing humidity levels should be simalar to the expansion or contraction of the art. (That is, presuming your art is made of paper and not polyflute or foamboard.)
Hi Cathy,

I hope Hugh sees this one, but IMO part of the problem is nomenclature - mount, support, backer, filler, backboard...yikes!

I call what goes directly behind the art the backmat. The art is hinged to that, whatever you call it. Ideally, that will be alpha cellulose or rag matboard, 4 or 8 ply depending on size. That is because it helps buffer changes in Relative Humidity.

I suggest people use the Artcare with zeolites when the art itself is most likely generating harmful volatile acids, peroxides etc. So for a watercolor on good quality paper I probably wouldn't bother with Artcare backmat, but for something with poor quality paper, or oil based inks/paint, I would.

Coroplast "filler" I think you call it - I call it the "final backboard" - is great because it is a good moisture barrier. But the edges need to be sealed. What I have seen work well in moderate water exposure is Coroplast, that really heavy brown tape at the edges (pressure sensitive, probably full of nasty stuff but VERY strong and water resistant,) with a strainer screwed into the frame at the reverse.

Of course for the best protection, you have to use Hugh's Marvelseal method.

There are so many variations....

BTW for my nice but not terribly valuable or semental stuff I have it hinged to "acid free" foam board, alpha cellulose window mat, and leave it at that. For the good stuff, it's the works.

A preservation mat package comprises a 4-ply window and a 4-ply back mat, hinged together with
water-activated linen tape along the long side.
The backing board, whether it is foam-centered or
polyflute should be a separate component. This is
for three reasons: the board, to which the art is hinged should have some possibility of expanding
and contracting, as the paper would, the mat package should be something that can be stored
separately from the frame (this is hard to do if
the window and back mat/board are not the same),
those who take the frame apart, in the future,
should not be surprised to find the art is hinged
to the backing board, since museum practice would
preclude this.
This does impose an added expense on those who
follow this standard, but preservation framing
can not be done on a cut-rate basis.
The public should be warned, "Never look for a
speedy conservator or a cheap framer."

I want to point out that I have been backing everything with RAG board for a while now.

Not bragging, just want to point out that it doesn't have to be expensive. I buy a 4-ply discontinued rag (creme colored) for less than $4 a sheet.

If you want to do it right, money should not stop you. Ask your distributors. Mine sells it in boxes only, but since I back everything (except for posters to foam) with it, I actually buy it a couple of boxes at a time.
Originally posted by Rebecca:
...Coroplast...I call it the "final backboard" - is great because it is a good moisture barrier. But the edges need to be sealed...Rebecca
What is the purpose of sealing the edges of the fluted polypropylene reinforcement? Are you concerned about harboring insects or something like that in the air gaps between the flutes?
I think she meant the edges of the coroplast to the frame, Jim, not the edges of the coroplast themselves.

Taping the coroplast edges to the frame would provide a good moisture barrier if done correctly with the proper tape.

Thank you Framerguy, yes, that's what I meant. The tape runs around the perimeter of the Coroplast and laps over onto the back of the frame.

Gotta love all this. So, I'm doing what I said: double 4-ply Alpharag mat, art hinged to Alpharag which is used as my backer, then another 4-ply "filler" to finish. The only reason the "filler" board is another 4-ply instead of coroplast or something is because the pieces are only 13 x 11 and I'm beginning to compromise the rabbet.

I'm awaiting the answer on sealing the coroplast edges as well. Rebecca, I took it to mean you were wrapping the edges of the coroplast itself.

What fun.
Thanx to Hugh, Rebecca, and all you other CPrs.
Originally posted by preservator:
A preservation mat package comprises a 4-ply window and a 4-ply back mat, hinged together with water-activated linen tape along the long side. Hugh
Further, according to PPFA guidelines, that long side would be the top edge for landscape orientation, or the left side edge for portrait orientation.

If that seems like nit-picking, points were deducted from the MCPF exam score for one of my portrait-oriented test frames, because I had the audacity to place the linen hinge on the right side instead of the left side.
Now I simply must ask...and I'm a rule follower: what in the world difference could it possibly make on which side of a portrait orientation you placed your tape??
I believe the idea is 1. for consistency and 2. because it's to open like a book, which is usually bound on the left side.

(If in a country where reading is from right to left, perhaps the right side would be bound.?)
No difference, just consistency. We westerners are used to opening a book with the hinge (spine) on the left.

maaaannnnn....gotta work on my typing speed. Uh, what Amy said, yep.
Let me get this straight, not to sound stupid, it's just sounds so simple.

When museum backing, you use Just plain ol' Artcare mat board from say, Bandbridge?

Does it matter what color, and I am assuming you use the colorless side, right? Or does it have to be the 4ply and only in the white or cream?

What again is the problem with Acid Free Foam core, or did you answer that already using a different namebrand?
Ref hingeing mat/back mount - What Jerome said,

When you open the 'book' it makes sense to position the artwork with your default hand and hold the 'book' open with the other.

With bottom weighted mats I have sometimes hinged on the 'wrong' side and I simply cannot position the artwork correctly with my 'wrong' hand, I have to turn the whole thing upside-down.