Direct-Glue Horseshoes – Assuring Adhesive Bond Joint Quality
While virtually all polyurethanes can be painted and/or bonded, coatings do not adhere to every resin system in the same way. Therefore, before attempting to bond/glue any polyurethane surface, several steps must be taken to properly prepare the part for bonding. The quality and durability of an adhesive bond to a polyurethane surface is directly affected by, at least, three factors:
- Proper resin/hardener mix ratio and curing – Sound Horse controls this in factory production processes
- Cleanliness of part surfaces
- Abrasion or etching of bonding surfaces (Flexx shoes have factory prepared bonding surfaces)
NOTE: If cured polyurethane parts are oily and “slippery”, rather than clean & dry, attempts to bond these surfaces will be futile. A typical cause of bonding problems is improper mix ratio, incomplete curing or residual release agent.
CLEANING: Remember: Saving time via “shortcuts” is a fast way to produce reject parts and failed bonds!
Part surfaces must be thoroughly prepared before adhesive bonding. Release agents found on a urethane part (horseshoe) are production lubricants that will contaminate any surface that is touched while handling. SOUND HORSE has added a parts cleaning step to remove residual contaminants, including release agents that have been used on production tools when manufacturing our FLEXX horseshoes. For this cleaning process, we use an aqueous process with appropriate detergents that are particularly effective in removing release agents, grease and oils from polyurethane horseshoes.