Trying to find a source of a compariosn of current adhesives and a guide to which ones work with dissimilar materials (Delrin to styrene as an example).
Try this link for a list of magazine articles: http://index.mrmag.com/tm.exe?opt=S&sort=D&output=3&cmdtext=%22ADHESIVE%22 It should run from the most recent (very recent), back to 1966. Note that a couple of the articles are by Mike Rose. If you go here http://www.mrhobby.com/ and click on the first link below his contact information, you can get the story on the Cyanopoxy System. I think it'll attach pretty much anything to pretty much anything else. In an effort to become more "sophisticated" in assembling things, I got some Cyanopoxy, *and* various applicators for applying *small* amounts of adhesive. Haven't stuck myself to anything for awhile now. (Well, okay, maybe that's the nitrile gloves.<G>) Hope this helps. -- Doug C. "Honey, I need to borrow your nail polish remover again!" Message 3 Date: Thu, 20 Feb 2003 10:32:36 -0500 From: "Andrew S. Miller" <[EMAIL PROTECTED]> Subject: Re: Adhesive compariosn chart or guide Try: http://www.thistothat.com/ -- Regards, Andy Miller Message 5 From: Tom Persoon Subject: Re: Adhesive comparison chart or guide Dennis, IIRC, there was a chart or article published in Model Railroader a few years ago. There are basically 3 kinds of adhesives for modelers use: Solvent cements, such as Tenax 7R and Plasticweld. These work by the solvent or solvent mixture dissolving the surface of the materials to be joined. Then the solvent evaporates and the two materials are bonded by an "intermingling" of the molecules at the surface. Tenax is pure solvent and Plasticweld contains a small percentage of a filler. They will work only on materials that will be dissolved by the respective solvents. Generally, they work only on plastics that contain one or more of the "ABS" polymers - Acrylonitrile, Butadiene, Styrene. Delrin is a polyacetal so would not likely be dissolved by the common solvent cements. Solvent-based adhesives, such as Walthers Goo and other hobby cements. These contain an adhesive material dissolved in a solvent. When applied, the solvent evaporates and leaves the adhesive which then binds the materials. These adhesives are generally good for dissimilar materials. They have two advantages: 1)The adhesives act as a filler, so the surfaces to be bonded to not need to be perfectly smooth or matched. 2) The adhesives tend to be flexible so the bonds can withstand a shock without breaking. There are two disadvantages. 1) If one of the substances being joined is attacked by the solvent, it will be damaged by the adhesive. 2) The bonds are not as strong as with polymer adhesives (see below). Polymer adhesives include alpha-cyanoacrylate (ACC) and epoxies. These work because a chemical reaction occurs in the adhesive that causes it to harden and bond to surfaces. In the case of ACC, the reaction is initiated by water vapor in the air or on a surface (that's why they stick to your fingers so fast). With epoxies, the reaction starts when the two components of the epoxy are mixed. In both cases, the adhesive needs some time to "set". Most ACCs set within a matter of seconds, while epoxies can take anywhere from 5 minutes to 24 hours. Polymer adhesives generally work well with dissimilar materials and usually won't damage the material because they contain no solvents. Another advantage to polymer adhesives is that the bonds are stronger than those of solvent-based adhesives. But, they have disadvantages, too. 1) The bonds are brittle and cannot take strong shocks. Some polymer bonds become more brittle with time. 2) ACC requires very flat surfaces to bond well (although the gel-types get around this somewhat). 3) Epoxies require more surface area to form a good bond. Bottom line - there is no universal adhesive, you have to choose the right one for the job based on the materials, required bond strength, and flatness of surfaces to be joined. For Delrin to styrene, I'd probably choose ACC if the parts are small and epoxy if the pieces are large. Delrin was designed to be a metal substitute. It is solvent resistant (hence solvent cements won't work). For more on delrin see: http://heritage.dupont.com/floater/fl_delrin/floater.shtml http://www.interstateplastics.com/meta/fmdel.htm ===== Ted Larson __________________________________________________ Do you Yahoo!? Yahoo! Tax Center - forms, calculators, tips, more http://taxes.yahoo.com/ S-Trains list sponsor: http://www.americanflyertrains.com All the Flyer you desire...books and accessories too! To UNSUBSCRIBE from this list send a note to [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
