I was in Home Depot today and I saw a tube of Bondo Polyester Resin Hardener. It is a liquid not a paste like the red or blue hardeners used with glazing putty or body filler. This hardener is designed to be used with the Bondo Polyester Fiberglass resin.

All glazing putties and body fillers that I'm aware of are polyester based.

Are all polyester resin hardeners interchangable?

In otherwords, can I use the liquid Bondo Polyester Resin Hardener in place of the red or blue paste type hardeners.

The reason I ask is that I only use very small amounts of glazing putty and estimating how much paste type hardener is rather imprecise. The instructions on the bondo polyester resin hardener say to use 10 drops per 2 ounces of resin.

I can weight the resin then add the appropriate amount of hardener.

Thanks