Customer Reviews
Rock Tumblers

 Home » Thumler's » Rotary Tumblers » MP-1 Kit

The Perfect Rock Tumbler Kit for the Beginner


Small, Economical, Quiet, Easy and Fun!

Thumler's Tumbler MP-1
This is what you receive when you purchase the Thumler's MP-1 Rock Tumbler. The kit includes the tumbler; a rubber tumbler barrel for quiet operation; a booklet titled "A Guide for Rock Polishers"; a grit pack that contains the grit and polish needed to tumble one batch of rocks; a package of rocks that are properly sized for this tumbler; and, a packet of jewelry findings that will enable you to make a necklace with pendant, a keychain, and a pair of clip-on earrings using some of the tumbled stones that you will produce. More photos below.

Age Recommendation
For use by children ages 14 and up
with close adult supervision.

Find out why.

MP-1 Rock Tumbler Kit

MSRP $119.11
Our Price: $99.99

Tumbler and Supplies


MP-1 Refill Kit


MP-1 refill kit
With this kit you get all the rough
and grit needed to tumble and polish
another batch of stones.

Only $19.99

Thumler's MP-1 Rock Tumbler



Here's what you get in this MP-1 rock tumbler kit...



    - A Thumler's MP-1 rock tumbler with a durable
      plastic base that encloses the motor.
    - Two-pound barrel (tumbles about one pound of rock).
      The barrel is made of soft rubber for quiet operation
      (see video below for sound comparison).
    - Rough rock to produce one batch of tumbled stones.
    - Grit & polish to process one batch of tumbled stones.
    - A booklet: "Guide for Rock Polishers".
    - A jewelry kit to make gifts from your tumbled stones.
    - Thumler's Tumbler Warranty.


Product Description - Who is the Intended User?



The MP-1 is a beginner's grade tumbler that is a perfect rock tumbler for a person who wants to try rock tumbling without making a big investment. It is not a toy tumbler with a plastic barrel that will stop working before it tumbles a few batches of stones.

In our opinion, the MP-1 Tumbler is the lowest-priced tumbler on the market that is quiet, easy-to-use, will last through many barrels of rocks, and will last the average user for many years. Because of its small size, it has a low operating cost for rough, grit, polish and electricity.

This tumbler is recommended for users who are age 14 and up. If you have a child who is interested in rock tumbling, this is a project that you should always do with your child. The tumbler has an electric motor, moving parts, and the barrel requires a little strength and practice to open and close.


This is an Entry-Level Hobbyist Tumbler, Not a Toy



Many department stores and websites sell toy tumblers with a hard plastic barrel. If that hard plastic barrel is not lined with rubber, it will make a LOT of noise when the rocks are being tossed around inside. The MP-1 has a soft rubber barrel that is durable and quiet. See the video below for a demonstration of its noise level.

The MP-1 is durable enough to tumble many batches of rocks. In our opinion, it is well worth the small increase in price over plastic-barrel tumblers. Unlike the toy tumblers, MP-1 replacement parts are available to keep your tumbler running smoothly for years.

MP-1 grit pack
Tumbling rocks in the MP-1 tumbler is a four-step process. First you tumble them for one week in "coarse grit", then one week in "fine grit", then one week in "prepolish" and a final week in "polish". The tumbler comes with these materials in premeasured packages. Refill kits are always available here.
We could sell thousands of plastic-barrel tumblers. We do not sell them because we know that our customers would be disappointed, and we would get a lot of returns. That's no way to run a business.

If we are not willing to use a product ourselves, we do not sell it.

We bought one of the first MP-1 tumblers in 2009, and we still use that same tumbler today. We have tumbled dozens of batches of rocks in it. It has the original barrel, motor, drive shaft, idler shaft and pulleys. We have replaced the belt once.


Everything You Need to Get Started



The MP-1 tumbler kit has everything that you need to get started. It includes: a tumbler machine, one soft rubber barrel, a package of rough rocks ready for tumbling, a four-step grit kit, a jewelry kit, and a book to guide you - "A Guide for Rock Polishers". Refill kits with all rough rock and grit needed to run the tumbler are also available.

The kit will enable you to tumble one batch of rocks from rough stones to finished gems. That process requires four or five weeks. You will need to stop the tumbler, clean the rocks and barrel, and recharge it with fresh grit and water every week. Once you have a little experience, you can do that easy job in a few minutes. Many people do that job on Saturday morning, and every four to five weeks they have another batch of beautiful tumbled stones.

The MP-1 rock tumbler is a durable machine that you can use to tumble many batches of rough rocks into finished gems. To tumble a batch of rocks, you will need about 1 pound of tumbling rock and about two to three level tablespoons of grit or polish for each of the four tumbling steps.

MP-1 jewelry findings
The tumbler is also supplied with a small jewelry kit that you can use to make gifts from your stones. The kit allows you to make a keychain, a pair of clip-on earrings, and a necklace with a pendant. You can always purchase additional jewelry finding kits here.
The kit contains enough rock to tumble one batch of stones. After that you will need to supply grit, polish and tumbling-grade rocks. Refill kits are available with pre-measured grit, polish, and rough rock. The rough rock (mostly agate and jasper) is already properly sized and prepared for tumbling.


What Does it Sound Like?



This video compares the sound level of the Thumler's MP-1 with one of the inexpensive toy tumblers with a plastic barrel and a tiny motor. To learn more about tumbler noise see our article: How much noise does a rock tumbler make?



Answers to Common Questions From Customers



Where Can I Get a Refill Kit? We sell refill kits designed especially for this tumbler. They contain the right amount of rock, sized perfectly for the small barrel of this tumbler. They also contain, in premeasured packages, all of the grit and polish that you will need to produce one batch of tumbled stones. Just open them and dump them in. Step-by-step instructions are included. Get a refill kit here.

Where Do I Oil the MP-1? The motor of the MP-1 is enclosed in the case and does not require lubrication. The tumbler has four bearings, two on the ends of the drive shaft and two on the ends of the idler shaft. The bearings and drive shafts should be wiped clean with a soft cloth and be given one drop of oil after each month of operation. Learn exactly where to oil the bearings here. Household oil or SAE 20 oil is recommended for the bearings.

Why is the Barrel Shedding Particles of Black Rubber? This is normal and will decrease with time. As the tumbler barrel rolls on the shafts, it sometimes rubs the barrel guides. This can wear a small amount of rubber from the edge of the barrel. This will eventually decline to a negligible amount.

Why is the Barrel Lid Getting Thin? As the tumbler barrel turns, the rocks and grit are continuously rubbing against the inside of the lid. Over time this will wear the lid thinner, and eventually a hole will develop in the center of the lid. You don't want this to happen when the barrel is on the tumbler and full of water, grit and rocks. So, each time you open the tumbler or load the barrel, you should press on the center of the lid to see if it is flexible. That signals that it is getting thin. If you can detect that the center of the lid is getting thin, replace the lid before you load the tumbler. If the lid wears through while the tumbler is running, the muddy water from the barrel can leak out and make a mess. Lids usually last through many batches of rocks.


A Rock Tumbler Story:



My father bought a small Thumler's Tumbler in the 1960s and gave it to me as a Christmas gift. I still have it, it still works great, and it has polished hundreds of batches of rocks. Now, over fifty years later, that tumbler is still in service. We use it regularly to test some of the tumbling roughs that are sold on this website.

We keep it clean and oil it regularly. In fifty years it has needed a few new belts, a few new lids, two sets of barrels, and two new motors. The service that we have received from that tumbler convinced me that it has been a durable machine that was made to last a long time.

My father didn't realize that his gift of a tumbler would one day result in a family-owned and operated business that today employs his son, daughter, granddaughter, grandson, and daughter-in-law.

The Thumler's A-R1 and A-R2 tumblers sold on this website are almost identical to the tumblers that were sold 50 years ago. In fact, all of the replacement parts sold today still fit those original tumblers! Very few products persist so long in the marketplace without major changes. Many of our customers are using A-R1 and A-R2 tumblers with their grandchildren that they received as a gift during their own childhood.

The Thumler's MP-1 tumbler, a "beginner's" grade tumbler, was first available for sale in 2009. We bought one of those early MP-1's in 2009 and we are still using it today. It has tumbled dozens of batches of rocks and is still going strong. It still has its original barrel and it still has the original motor. You will not get that kind of service out of a "toy tumbler".

Hobart King
Owner/Manager
RockTumbler.com