Rapid Prototyping involved creating a working model of various parts of the system at a very early stage, after a relatively short investigation. The method used in building it is usually quite informal, the most important factor being the speed with which the model is provided.
There are water-and solvent-based -- also called oil-based -- polyurethane varnishes. Water-based polyurethanes are more environmentally friendly and safer to use than solvent-based, but they are not as resistant to wear and tear as solvent-based products.
Urethane Vs Polyurethane. Water Based vs. Oil Based Polyurethane. Polyurethanes, on the other hand, leave hard and durable coats that are best used for hardwood floors. There is not much difference between polyurethane vs. varnish since polyurethane also has some of the advantages and disadvantages of varnish. Polyurethane is newer than varnish, so some old-timers may advise against using it. However, itâs so easy to use that even a beginner could apply it correctly.