I also use an convection style (no fan) heater - propane in my case - in my shop and hardly notice any smell. It doesn't set off the smoke, CO and gas detectors. At 35,000 bthu it heats quickly so I turn it off after 10 - 20 minutes and use a small electric heater to maintain the temperature.

I find that an insulated garage holds the heat well - it is still noticeably warm the next day, expecially if I have been working for a few days, even in a Canadian winter.

If you have to leave epoxy to set for a few days you can cover the work with a tarp and use an incubator lamp for local heat; a dimmer switch would give you a range of heat. Work safe!