Making tumblers is a fun and exciting way to dig into your creative side and end up with a great product that can make you some excellent side monies. Most people, however, hate one part. But here, I am going to show you how to prep a tumbler two ways. First, the hard way. Second, the way that will blow your MIND.

Why do you have to prep a stainless steel tumbler?

Making epoxy tumblers is a really fun and profitable side hustle. But you have to make sure you do all the steps to make sure your end product is beautiful and long-lasting.

Stainless steel tumblers come with a coating that helps to protect them from rust and corrosion.  It also repels water, as you can see in the picture below.  Also spray paint is not commonly water-based, this coating can also cause your cup to repel the spray paint.

But do you absolutely have to prep a tumbler?

I won’t lie and say that I’ve never heard of people skipping the prep step and going right into spray painting.  People do it and people have had luck with it.  I, however, don’t understand skipping a step that obviously will help your cup’s beauty in the long run.  Especially when that step only takes a few minutes of extra work.

What do I need to prep a tumbler?

There are two ways to prep tumblers that I am going to go over in this post.  One involves sandpaper and LOTS of elbow grease. The other involves a liquid chemical prepper.

Sanding a tumbler to prep it for painting

Prep A Tumbler: Sandpaper Method

• Tumbler
• Sandpaper block (I love the blocks more than the regular stuff)

This method just requires rubbing all surfaces of the cup with sandpaper to give it a good scuffing.  There isn’t really a hard and fast rule about the exact time you should sand.  Just make sure you get the entire outer surface of the cup, including the bottom.

Once you are done sanding, just make sure you wash the cup well and then touch in with your bare hands as little as possible, as the oils in your hands can affect not only the spray paint, but the epoxy as well.

Prep A Tumbler: Chemical Method

• Tumbler
• Klean Strip Concrete and Metal Prep
• Water
• Sponge brush

This is the method of sanding I recommend.  I am able to sand 20 tumblers in under an hour without giving myself tennis elbow.

All you have to do is mix metal prep and water in a 1:1 ratio, brush it onto cups with a sponge brush and let them sit for 30 minutes.  Then you wash them with soap and water and then try not to touch them.  

Prepping tumblers without sandpaper is so simple.  I highly recommend it.  Also, the bottle of metal prep is huge, so it will last you a while.

But those are my two recommended ways to prep a tumbler.  If you’ve found a different way let me know.

If your curious about more tools I use to make tumblers, check out the resources page.