The duration varies; however, using a standard tumbler (C1 Rock Tumbler) typically requires about 4 to 5 weeks of continuous operation. The process consists of four steps: coarse grinding, medium grinding, pre-polish, and final-polish, with each step taking roughly one week.  

Yes, tumblers are an excellent way to introduce children to the lapidary hobby. The process is straightforward, and although it takes time, kids enjoy the final results. It’s a great way for them to learn about the natural world. For more details on starter kits, check out this blog post.

In addition to a tumbler, you will also need silicon carbide grit, appropriate rock polish, and a selection of rocks. Silicon carbide comes in various grits, from coarse to fine. Our rock tumblers come with all the accessories a starter needs! All kit components also can be purchased separately for restocking. You can easily find rocks at beaches, rivers, or local gem shows. Tumblers are available with optional starter kits or as part of complete packages—browse our selection of rotary tumblers in various sizes.

Some users opt for coarse river sand instead of silicon carbide grit, but this method is slower and offers less control over the grinding process. We do not recommend it, as silicon carbide grit is inexpensive and much more effective.

While vibratory tumblers can be quite loud, KoolStone Rock Tumblers have solid rubber barrels designed for quiet operation.

NO. Because grit gradually breaks down as you’re tumbling, you cannot reuse it. We recommend that you thoroughly wash your rocks before putting them in polish – you also need to wash the barrel. Failing to do so will hinder your final polish results.

We recommend approximately 2 tablespoons of grit per pound of rocks. A rule of thumb is that, if you see grit at the bottom of your barrel after one week, you are using too much grit.

These models serve different purposes; for beginners, a rotary tumbler is often recommended due to its ease of use and lower monitoring requirements. While vibratory tumblers work faster and require fewer consumables, they need to be checked twice daily for slurry consistency. Rotary tumblers operate more quietly and can be left unattended between stages. For more detailed information, see our comprehensive article. 

We suggest you put rocks mixtures of anymore between 1 to 1.25 inches, the maximum size of the stone should not exceed 1.5 inches. Moreover, we do not recommend tumbling any medium that is less than 1/4" in thickness/length. 

There are two basic rules that you should follow about the sizes of rocks that you load into your rock tumbler:

1) Load the barrel with a mixture of rock sizes.

2) Tumble rocks no larger than about 1/2 the barrel diameter.

The first rule is one that everyone should follow. The second is for people who want to make "monster" tumbles. 

1) Always keep the outside of your barrel clean. 

2) Apply a very small amount of lubricating oil to the bearings every 30 days of operation. 

3) Make sure the drive belt has the proper level of tension – not too tight but not too loose.

Like anything else, the more you take care of your rock tumbler, the longer it will last. 

KoolStone provides comprehensive warranty support, covering tumblers for 12 months, handled at our warehouse. Often, we can assess issues remotely and provide parts. In rare cases, you may need to return the machine for evaluation, but warranty concerns are infrequent as our machines are durable and reliable. We maintain a complete inventory of spare parts and accessories.