There’s a big debate in the guitar world over nitro and poly finishes and which are the best. In this article I’ll be comparing nitrocellulose, polyurethane and polyester finishes and discussing the pros and cons of each type.
The Quick Answer
Polyurethane guitar finishes are more durable and less susceptible to fading, chips and scratches compared to nitrocellulose finishes. Nitro finishes are typically seen on older or high-end guitars. Poly finishes are more common because they are cheaper and easier to apply and better for the environment.
Nitrocellulose are predominantly used in high-end guitars, however are less commonly used today compared to in the ’50s and ’60s where both Fender and Gibson utilised them. Currently, Gibson still use nitrocellulose gloss and satin finishes for both the necks and bodies on most of their guitars, whilst Fender typically only use them on custom shop models.
Nitro finishes are more time-consuming and labour intensive to apply. The lacquer is compromised of nitrocellulose and solvents which ensures it is the appropriate consistency to spray onto the wood. The finish is applied in multiple layers over several days. Once dry, it is buffed to a gloss or satin finish.
The nitro finish is slightly porous compared to poly finishes, which means it’s softer. This makes it easier to damage but also easier to repair. Some players are a big fan of the relic finishes which have an aged look due to the yellowing and cracks that appear over time in the nitrocellulose lacquer.
Nitro finishes are rarer today due to both the laborious application process and safety issues. Nitrocellulose is a high-VOC which means its use is strictly regulated as it poses a risk to the environment and manufacturing personnel.
- Ideal if you want a “relic” look
- Easier to repair if damaged
- Easy to chip and scratch
- Harder to apply
There are two types of “poly” finishes: polyurethane and polyester. Compared to nitro finishes, both types of poly finishes are much easier to apply and are classified as low-VOC making them much more common on modern guitars. Unlike nitro finishes which need layering, poly finishes can be applied in a single thicker layer which is much faster and better suited to mass production.
One significant advantage of poly finishes is their durability. The finish is very thick and hard, meaning it will not damage as easily and don’t fade as much over time. This also means that it is not possible to achieve a true relic effect with a poly finish.
Now back to the two types of poly finishes: urethane and ester.
Polyurethane finishes are seen on more premium guitars and are used on most American Fender models today. On more affordable guitars it’s likely you’ll find a polyester finish, for example of most Mexican Fender guitars.
Polyurethane finishes are softer and thinner which to some players feels nicer, but they are also softer than polyester finishes which are less susceptible to dings and scratches.
- Not prone to fading
- Unlikely to cause scratches and chips
- Hard to repair if damaged
- Can feel “plasticy” if the finish is very thick
Does the Finish Affect the Tone?
Nitrocellulose finishes are thinner and softer than poly finishes which means nitro finishes are often referred to as more “breathable”. Some players believe that nitro finishes sound more resonant and have better sustain compared to poly-finishes, however it is very hard to notice the difference.
In reality, the difference is so negligible that the vast majority of players will never be able to hear it.
The conception that poly finishes sound “bad” because they aren’t as porous comes from their initial release where they were typically applied too thickly. Nowadays, the poly finishes are applied more carefully particularly on higher-end guitars which means they are far from inferior tonally compared to nitro finishes.
Check out this blindfold challenge on the Andertons YouTube channel to hear some Strats with polyurethane and nitrocellulose finishes being compared. If you want to take part in the challenge, then start the video at 1:23.
Look and Feel
Some players criticise poly finishes for feeling “plasticy” because they are applied in a thicker layer. However, both nitro and poly finishes are in fact plastic. It is usually only on cheaper guitars where you’ll notice the difference in feel between the finishes and this is typically a result of the overall manufacturing quality compared to the finish type being used.
Poly finishes are slightly glossier than nitro finishes and will retain this glossiness for longer compared nitro finishes which are more prone to fading. Aside from this, poly finishes are less likely to get scratched and chipped.
However, if you are looking for a relic finish, then you’ll want a nitrocellulose lacquer as the “aged” look is impossible to pull off to the same effect with a poly finish.
Which Guitars Use Poly and Nitro Finishes?
- Fender Mexican
- Fender American
- PRS Core
In the market for a new guitar? I’ve written a complete buyer’s guide for electric guitars which takes you through all the things you need to consider and a step-by-step method to narrowing down your selection and choosing the best option. Here is a link to the article.