I have a Plastruct square channel (styrene) and am trying to attach a different type of plastic (don't know the name) piece that is softer and a bit pliable. Actually, this other type of plastic is used as a needle cover for for diabetic supplies. It can easily be cut and sanded, and painted with solvent-based paints or spray can paints. I used regular styrene cement in my first attempt- it held after drying overnight, but then the part came off easily when I pulled it. I also experimented with CA cement, but with the same result after drying. Short of using a clumsy epoxy syringe from the hardware store (such as might be used for larger broken objects), does anyone have some alternate glue suggestions?
Have you checked the Plastruct website? Their products are made of several different types of plastic (ABS, styrene, butyrate, acrylic, copolyester, etc.) and they have specific glues to function on the different types. Once you know the type of plastic you can determine what type of glues will work.
When using pure solvent cements like Tenax 7R you get poor performance bonding dissimilar plastics. Plastruct General Purpose Plastic Weld has an additional binder in the solvent that helps for a better bond when joining ABS, Styrene, Butyrate or Acrylics to each other.
It is a tough go that won't respond well to epoxy. Rough up the surfaces with sand paper and use a small amount of a two-part epoxy. I think that will be a good solution, and reasonably quick if you have any handy. I always keep a small bit of the two parts around so that I can do odd little jobs, including such things as handing decorative plates that don't come with a proper method for hanging their weight. I drill carefully, epoxy metal pegs into the holes, and then use wire as one would for a picture frame. That stuff is hard and durable!
Loctite has a relatively new CA that is for difficult to glue plastics. I used it to glue diabetic needle covers to styrene when neither Tenax nor regular CA worked. The diabetic needle covers that I have (2 kinds, one of which glues just fine) look like some sort of HVAC vent or cooling unit. Is that what you are doing with them, TampaRon?
Larry: They actually look like large commercial light fixtures that might be used in a high-ceiling industrial or maintenance bldg. (I am cutting them down to resemble a light cover that an LED will go into, so as to not heat the plastic) Novofine is the needle brand. I am thinking that the plastic cover might belong to the poly-XXXX family of plastics, perhaps polypropylene, due to it's softness and flexibility. My next attempt is to buy 2 separate expoxy tubes in a set, rather than those "syringe-type mending kits"; then blend an inch of each (or as per instructions) and use a toothpick to apply the epoxy mix to the two plastics- advice received today from a guy at my LHS.
