The consistency of your putty is completely dependent on your preferences. Mix some linseed oil with the whiting until you get to a workable consistency like Play-Doh or if you are a baker, actual dough.
I find that adding about 1/3 cup of zinc to 1 quart of putty does the trick. You can also add Zinc Oxide to help control mildew growth on your putty if you live in a region that is particularly hot and humid like we are down here in Florida. Whiting is a little scarce these days, but I do sell it in my store if you can’t find it locally. Using boiled linseed oil will result in a faster curing putty, whereas raw linseed oil putty results in a longer lasting flexibility with the putty, so, there is a trade off. You can find linseed oil at most hardware and paint stores. Traditional linseed oil putty was made from only 2 items.
Glazing putty doesn’t keep forever, so just make a batch large enough to handle what you plan to glaze in the next week or so and then make some more if you need it later. Or maybe you are one of those hardcore DIYers who like to make everything yourself. The commercial putties on the market like Sarco MultiGlaze that we sell are a little better than homemade recipes and always more consistent, but the homemade stuff can work great when you just need a little batch. You may have thought that you can only buy glazing putty from us here at The Craftsman Blog, but did you know you can make your own glazing putty in a pinch? That’s right! It just take a couple basic materials available at home improvement or paint stores and you can make traditional glazing putty just like the old timers did.