The Framers Forum

Hello guys,I have a couple of questions hopefully somebody can help.
I took a couple of framed prints to a local framer to have the glass changed to u.v. glass.
When I examined them at home the print is flush to the glass.In the past any framing I had done there was always a little space between the print and the glass.The framer said it was fine to be like this because of the u.v. Coating on the glass.
Is this true?,the prints are valuable and I have read elsewhere that the print should not be in contact with glass.
Hope you guys can help.

Regards

I don't think that is fine at all. There is a very real posibility of micro condensation forming on the inside of the glass and therefore adversely affecting the print. All it takes is the right amount of humidity in the air, a difference in temperature and that's when the dew point allows the condensation to form on the inside of the glass. Don't just take my word for it, but look up " dew point" on an internet search engine and see how it works. I am trying hard to understand why your framer would think that the U.v. coating would prevent this. Well I am sorry, but that's not my understanding at all. All it takes is a nice warm room, the right level of ambient humidity and someone opens a door leading to a colder part of the building and the temperature in the room drops.

Room temperature go through a cycle each day and the room cools at night and warms up during the day. This is generally a gradual process, by it has the effect of the air inside your picture frame expanding and contracting and when the air expands some of the air finds it's way out in to the room and when it contracts it sucks air back in from the room. The same thing happens with the air inside your house and the air outside your house. The point I am making is that the humidity in your house will track with the humidity outside your house and the humidity inside your frame will track with the humidity in side your house and all it takes is a relatively rapid change of sufficient temperature difference in a rooms ambient tempature with enough humidity present and the change will produce the dew point and that's what causes the micro condensation on the inside of the glass.

Sorry to tell you this, but your picture framer oughtt to know this and have at least some idea about this. It is generally thought by many people that mounts are added to picture frames for their decorative effect, but mounts were originally added to keep the artwork from touching the glass and this is still the primary reason for using mounts to prevent damage to the artwork from micro condensation being transferred from the glass to the artwork. The potential to use a mount for decorative purposes is secondary in importance to the need to protect the artwork from the long term effects of this micro condensation. there can be an additional benefit to using a mount on larger artworks, where provision can be made to allow the artwork to expand and contract with seasonal variations in humidity, without causing excessive rippling of the artwork, if it is on paper.

I hope this helps.

Thanks for the reply

I'd be inclined to agree with Mark.

I normally tell my customers that I don't recommend glazing directly touching artwork as condensation can form on the inside of the glass, which in turn will be soaked up by the paper.

I don't fully understand the science behind it but this is to do with the thermal properties of glass, so the glass can cool quickly so I don't think UV coating would make that much of a difference to this. Acrylic glass is different as it doesn't heat up or cool in the same way.

If they don't like the look of a window mount, I offer a spacer in between the artwork and the glass.

If you took the artwork to be re-glazed, what was it like before?

Did you discuss it beforehand with the framer?

One of the main manufacturers of UV glass for the picture framing industry is Tru Vue - you could try contacting them to see what they say, although the glass your framer has used may not be Tru Vue.

If there was a spacer in originally, I wouldn't have removed it unless I thought there was a good reason for doing so, and even then, not without discussing it with the customer.

If there wasn't a spacer in originally, I would have recommended to the customer that I put one in, because I'm not aware of UV glass being different to ordinary glass with respect to condensation, although your framer may know differently.

It's an interesting question and I can see why you've got misgivings. If you do contact Tru Vue and get an answer, do post back.

Thanks for the reply very helpful.I will keep you posted certainly.

I believe from your post here and also on The Grumble you now have all the info you need.
Rainbow suggested asking Tru Vue, so here is your contact if needed

Dot Heckle

Director of Marketing

Tru Vue, Inc. | 9400 West 55th Street | McCook, IL 60525 USA

Phone: 708.427.1352 | Fax: 708.485.5980

www.tru-vue.com

dheckle@tru-vue.com

If these prints are valuable and the framer has not taken steps to avoid then coming in to contact with the glass, then has he taken appropriate steps to use framing materials suitable for conserving these valuable prints. Are these prints backed with conservation quality mount board, or only standard quality mount board? Also if these prints are in anyway attached to the under mount if the framer has bothered to include an under mount how are they attached to the under mount. If the means of attachment is not reversable, or not using conservation level attachment methods and materials, how do you know that the value of the prints has not already been compromised.

I've even seen prints hinged with tape attached with tape adhered to the front face of a print, using a hinging tape of obviously non reversible tape and had to tell the customer to take the print to a conservator and get the tape professionally removed, which they did, but when they brought it back to be re-framed the non reversible tape had discoloured the paper and effectively severely compromised the future value of an otherwise valuable print. In view of the very obvious damage I did not want to frame it at all, because I did not want anyone to associate myeas the framer with the poor state of the damaged print.

The customer was very upset about what had happened to the print, because of the ignorance of the original framer, who did not have any idea what he was doing. Unfortunately there is no shortage of amateur framers around who offer framing to the public and simply have no idea of the damage that they are causing. There is a lady who is local to me and frames cross stitches by sticking them down onto board using Evostick impact adhesive and still continues to do so. She is very anti me, because I told one of her customers that a valuable old sampler had been ruined by sticking it down with Evostick. It was then taken to a conservator, who said that the damage was too severe for it to be economically saved.

The lady in question is very popular with customers who want cross stitches framed, because she is so cheap. She uses mass produced ready cut mounts made from cream core cheap mount board and her frames don't properly met at the corners, but she probably frames more cross stitches that me. She used to come to me to get glass and backing boards cut to size at one time.

It is NEVER acceptable to have artwork touching the glass. Or anything else.
If the frame is hung in a stable environment and stays there, then chances are nothing will happen. However, this circumstance
is never likely to occur. The danger comes when there is a sudden shift in temperature/humidity. The frame gets moved to an
unheated room or stored in a shed - whatever.
Moisture will condense on the inside of the glass and migrate to the art. This can cause staining or in the case of photographs, sticking to the glass.
In certain circumstances plastic glazing can be used in direct contact. Plastic has different thermal properties to glass and is safer.

Whatever UV coatings the glass has has no bearing on the issue.

Sorry to jump on this topic, and whilst not Glass related I have been asked about perspex/styrene touching the artwork/football shirt.

I assume that the risk is still there of dew points, but are they reduced given the styrene doesn't change temperature to the same extent as glass?

I've always understood that the risk related to condensation is somewhat reduced when using plastic glazind vs glass, but I have no idea what the relative difference between plastic and glass would be.