All too often novice woodworkers don't realize the power of wood putty. No doubt, they have heard about it and perhaps worked with it once or twice but had poor results. Chances are they either used the wrong product or the wrong application or maybe even both. It is sometimes referred to as wood filler or wood patch. It may be a water base or a solvent based. Solvent base has probably been the favored choice in the past. The water-based products have really made some excellent strides in their performance and are now being used more.
There is nitrocellulose-based putty. This dries very fast. To clean up all you need is some diluted acetone or lacquer thinner.
A gypsum-based putty comes in a powder form and you have to mix the proper ratio with water. If you clean up while it's wet, it's simply done with plain water. If you let the gypsum dry and try to clean up with water, it just isn't going to happen.
Finally, an acrylic based putty will clean up with water as well until it dries then after that you will need to clean with acetone or toluene.
There are advantages to working with water wood-based fillers because they don't have the heavy fumes to them that the solvent-based ones do and they are easier to work with. What woodworkers like about it the most though is how easy it is to clean up. It is also more economical for storage as it doesn't' dry out as fast as the solvent-based putties do.
All wood putty is really is a glue mixed with material such a sawdust or gypsum for example. It creates a binder that holds the filler together.
Once you get used to working with wood putty ideally, you will want to keep both on hand if you are an avid wood worker or do it yourselfer.
Knowing which putty to use in the beginning may be a bit of a challenge. You want one that is going to stick and not shrink once it has dried. Another attribute about a good filler is you should need to sand it a great deal and it should have a satin finish to it afterwards.
Woods like poplar, rosewood or walnut just to name a few have very large pores and open grains. You can use wood filler to even out some of the grains in these types of woods.
Another good feature about wood putty is that it comes it different colors, which makes it much easier for blending. Ideally, before you use any of the colors check it on an unobserved piece of the wood to see what the end result is going to be. It may come out lighter or darker than you intended. If you are new to using wood putty ask your local paint supplier which seems to be the favored by most of their customers. This often gives you a good indication on how good and effective a product will be.