Hi David, It is hard to comment on this particular situation without seeing the problem, but I agree with most of the comments expressed so far, especially Tony's.
The one new thought that I have that has not been mentioned yet is that I would take a two step approach. The first thing I would do is focus on joining the loose piece (if it is actually loose) to the main piece with high attention to detail and accuracy from a cosmetic/functional standpoint...then I would worry about backfilling the gap. I have done jobs in the past where I was trying to "blind glue" a loose piece without disassembling the whole job, and I have wound up with a big mess due to applying the volume of material necessary to backfill a gap before I had the loose piece secured in the desired position. I would tack it first, then be able to focus my attention on the backfilling job without having to worry about the positioning of the loose piece. Silicone is good, but may not fill all of the gaps - but that might not even matter. Epoxy is good too, and will soak into the porous stone and create a good bond, but it is typically quite brittle and does not lend itself to applications where thermal movement is expected...and on a vertical application could make a mess in the amounts necessary to fill a large void. Also, the chemical reaction that takes place as epoxy forms its matrix creates a LOT of heat if a large volume of material is used at once. Once again, without being able to see the piece, I would use a small amount of cyanoacrylate or aliphatic wood glue to secure the piece, then look for something to fill the air gap behind it. If you are worried about this "backfilling" material running out of any cracks, use silicone. If not, look into the possibility of using a thin cementitious floor leveling compound or somesuch material that will have a similiar expansion coefficient as the stone itself. Take care and good luck, Jim Tallman Sr. Designer FX Studios 513.829.1888 ----- Original Message ----- From: "John Carmichael" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Monday, November 25, 2002 9:14 AM Subject: Re: flaking sundial > Hi David: > > I agree with Tony that injection through a hole could cause a hydraulic > effect that could actually widen the gap. Also, these glues and silicones > are so viscous that they probably wouldn't fill the entire gap. > > Bonding agents work best when thin coats are applied to both surfaces and > when pressure is applied until the agent dries. > > I know this sounds radical, but I think your best bet would be to carefully > make a clean cut or break into the uplifted stone sheet so that it could be > removed from the stone. Then it should be fairly easy to coat with adhesive > the bottom of the sheet and the top of the stone for rejoining. I'd press > the sheet down onto the stone with even pressure using a flat board so the > sheet doesn't crack and let it dry. I'd use 50 year silicon from a glue > gun. > > John > > John L. Carmichael Jr. > Sundial Sculptures > 925 E. Foothills Dr. > Tucson Arizona 85718 > USA > > Tel: 520-696-1709 > Email: [EMAIL PROTECTED] > Website: <http://www.sundialsculptures.com> > ----- Original Message ----- > From: <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Monday, November 25, 2002 12:14 AM > Subject: flaking sundial > > > > Object - a vertial south sundial of 1700, in a sandstone type of material. > > It is 24 inches square. with carved numerials and hour lines. > > > > Went tapped, an area about 12 inches diameter sounds hollow where a thin > surface area is detached from the backing of the 1.5 inch thich dial. > > > > Does anyone know how to secure this loose area to the sound stonework > behind ?. > > > > I quesstimate this loose area is about one eighth of an inch thick. > > > > Perhaps maybe drilling a tiny hole, and injecting some bonding agent. > > > > It is planned to do this work next year in warm weather. > > > > Your help much appreciated. David. > > > > > > _______________________________________________________________________ > > Freeserve AnyTime, only £13.99 per month with one month's FREE trial! > > For more information visit http://www.freeserve.com/time/ or call free on > 0800 970 8890 > > > > > > - > > > > > - > > -
