Re: ShopTalk: Coffee can oven

[Bernie Baymiller]

Bud,   Here's an old post from GS Tech dept. to DT with a table that might interest you:     "Date: 10-DEC-99 Author: Golfsmith Technical Dept. (Golfsmith) Subject: Re: Re: Epoxy and cold weather "Dave: "Here is some information we obtained from the our epoxy supplier. "All room temperature (ambient) cured epoxies can be accelerated by moderate heat (66C-82C) to speed the reaction between the epoxy resin and hardener. However, curing these systems at very high temperatures may adversely effect bond strength because of the following: The heat from the reaction exotherm combined with the externally supplied heat may char the epoxy system or cause outgassing and bubble formation, resulting in poor strength. Premature system gelation or interlocking of molecules restricts mobility of the molecules within the matrix and may result in an incomplete reaction. "On the other hand, most room-temperature, cured epoxy systems give better bond strength at moderate heat cure as compared to room-temperature cure. This is because of the better "wetting" of the substrate because the surface energy of the mixed epoxy is lower and the viscosity is lower." Our standard 24 hour shafting epoxy cures to a shear strength of 3500 PSI at 18 hours at 25 C. When the temperature is increased to 82C (180f) for one hour, the strength is 3650 psi. At 66C (150f) for two hours the strength is increased to 3800psi. "As a table (DMT added): Temp*C Temp*F Cure Time Shear Strength 25 77 18 hr 3500 psi 66 150 2 hr 3800 psi 82 180 1 hr 3650 psi I hope this helps. Mark Ehly"   Bernie Writeto: [EMAIL PROTECTED]  ----- Original Message ----- From: bud and marie To: [EMAIL PROTECTED] Sent: Sunday, September 08, 2002 9:42 AM Subject: ShopTalk: Coffee can oven All    I've been getting a ton of great ideas and experience from you guys.. now it's time for me to pass something along  that perhaps you might find helpful...if you haven't stumbled on this idea already..   was wanting to accelerate the epoxy curing of a driver head I had put together for use the next day.. from what I have learned approx. 100 deg.. is a good temp to heat the head for that purpose... so I experimented and stuck the driver head in a 3 lb. coffee can and laid a drop light on top of the can face down with the bulb pointing towards the can opening.. ..not shoved in.. but just laying on top..  first a 75 watt bulb heated the inside of the can to 140 deg... too much.. went to 40 watt bulb and it reached 120 deg... went down to 25 watts and the inside temp of the can stabilized at 103 deg...  that was done at room temperature.. left it over night and the club worked fine...   FWIW   Bud