I'm missing practical knowledge of the relative benefits and disadvantages of mounting RC papers up to 17x25 on foam core or gator using dry mount or cold laminating.
If you pre-press both the print and the mounting substrate to drive out moisture, I am pretty confident that dry mounting will out last laminate mounting by quite a bit. I adhesive mounted zillions of RC prints in the 70's, not a single one of the surviving lot is still attached today, or even ten years after the initial mounting. The worst attachments were RC->aluminum panel, ouch! But my 55 year old drymounted-in-high-school prints are still firmly attached to their highly non-archival Crescent mounting boards.
OK, RC papers... Not every dry mount tissue is RC friendly. After a lot of experimentation I finally found a tissue that worked great for RC->foamcore, and it wasn't the industry standard Colormount tissue which IMHO only works with extremely fast temperature rises which precludes the use of a substantial cover sheet. Sadly, that magical tissue is no longer available. So you need to experiment! Trying to peel up mounted RC prints may not sound like a lot of fun, but it can be a real eye-opener. When I did that stuff, I found that the time/temperature/pressure requirements for a good mount were very narrow, and that it was wise to err on the generous side of the parameters.
Could go on and on. Temperature accuracy is also extremely important. Most old presses with mechanical thermostats swing their temps way too high and way too low. Presses with electronic controls are much better. At around 220F RC paper will start to blister, so whatever else be sure your press doesn't go past that in its manic-depressive temperature gyrations. But RC papers can withstand up to 200F pretty much indefinitely. If you're buying a used press, be aware that it probably served a stint in t-shirts-at-the-mall Hell, where it was left permanently at the highest possible temperature by insensitive, loutish, teenage hooligans. Such presses will have several missing sections in the heating grid, and the platens will be trashed. OTOH, my pristine and enormously heavy 550-TX press is a joy to use and nobody may touch it but me even though I haven't done that in quite a few years.
How do test platen temperature? There are numerous non-contact infrared thermometer devices available on the net, some of them are small enough to insert under a fully opened platen. I bought one about 2" long from Harbor Freight, alas doesn't seem to be a stock item any more. Don't burn yourself. You can also heat up a thick piece of mounting paper, and read it the instant it emerges from the press. Be sure to test for evenness of heating, you may have dead sections in the heating element. You can also test with silly little overpriced test papers from some framing suppliers, the meters are miles ahead.
