Mixing your own polyurethane is super easy, it will not only save you some money, but you'll also be able to get the exact mixture you're looking for in order to achieve a perfect finish
1. Oil based polyurethane (in the gloss of your choice)
2. Mineral spirits
3. Glass mason jar for storage
4. Something to measure with (I used a solo cup)
Step 1: Identifying the proper polyurethane
In order for this finish to work properly you need to use the proper polyurethane. You'll want to use OIL based polyurethane, not WATER based polyurethane. Water based polyurethane will not thin with mineral spirits.
There are a couple ways to identify whether or not you've got water based or oil based polyurethane.
1. read the back label and it should tell you
2. the look of the polyurethane itself
If your label doesn't indicate the type of polyurethane it's easily identifiable just by the way it looks. Oil based polyurethane will be semi transparent and have an amber color to it. Water based polyurethane is white and milky.
Step 2: Mix up the wipe on polyurethane
Start by mixing up your polyurethane with a stir stick, making sure everything is combined and mixed evenly.
After mixing up the polyurethane measure out the amount you need. Since this process is so fast I like to mix mine as needed. I used a solo cup to measure mine because it has a lot of lines that make it easier for measuring. After filling it to a specific line remembering it pour it in to your glass jar.
The best mixture to start off with is 50/50 see how it goes, and adjust as needed. More mineral spirits for a thinner mix, less mineral spirits for a thicker mix.
After dumping your polyurethane in to the glass jar, measure out your mineral spirits by filling it up to the same line in your solo cup. Pour the mineral spirits in to the jar with the polyurethane, put the lid on, give it a good shake, and it' ready to use.
Step 3: Label your mixture
If I end up with leftovers after the job I like to label the mixture. Sometimes I'll have multiple jars of different finishes so it's important to keep track of what is what.
I like to put a piece of painters tape on top of the jar and write on that so I don't write on the actual top of the jar.
I'll label it with the type of gloss I used and the mixture of polyurethane to mineral spirits.