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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 $166.75
Our Price: $119.99

Tumbler and Supplies

MP-1 Refill Kit


MP-1 refill kit
With this kit you get all the rough, grit, and media needed to tumble and polish another batch of stones.
Only $19.99

Thumler's MP-1 Rock Tumbler



What you get in the MP-1 rock tumbler kit...


  • A beginner's tumbler that is quiet and long-lasting.
  • Tumbling rough for one batch of tumbled stones.
  • Grit and polishing powder to process the stones.
  •      (refill kits available here)
  • A kit to make three jewelry items with your stones.
  •      (keychain, necklace with pendant, earrings)
  • A booklet: "Guide for Rock Polishers".
  • A soft rubber barrel for quiet operation.
  •      (see the video below for sound comparison)
  • A durable plastic base safely encloses the motor.
  • The tumbler processes about one pound of rock.
  • Thumler's One-Year Limited Warranty
  •      (Warranty begins on the date of purchase.)

    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 one of the lowest-priced tumblers 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 under 14 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.

    MP-1 review
    Read a complete review of the MP-1 rock tumbler, written by an expert with decades of rock tumbling experience.
    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.

    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.



    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.

    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, rough rock, and media. 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



    MP-1 Refill Kit


    MP-1 refill kit
    With this kit you get all the rough, grit, and media needed to tumble and polish another batch of stones.
    Only $19.99
    Where Can I Get a Refill Kit? We sell refill kits designed especially for the MP-1 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 and a small amount of ceramic media are also included.

    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 that tumbler. It still works great, and it has polished hundreds of batches of rocks. Now, almost sixty years later, that tumbler is still in service. We use it regularly to test the tumbling roughs that are sold on this website.

    We have kept it clean and oiled it regularly. In nearly sixty years it has needed a few new belts, a few new lids, a few retaining rings, two sets of barrels, and two new motors. The service that we have received from that tumbler is convincing. The Thumler's A-R2 tumbler is a very durable machine that is made to last a long time. We have sold thousands of Thumler's A-R2 rock tumblers to customers all over the United States and have received very few complaints.

    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. Our business operates RockTumbler.com and publishes Geology.com - one of the most popular Earth science websites on the internet.

    The Thumler's A-R1 and A-R2 tumblers sold on this website are almost identical to the tumblers that were sold 60 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. If you have an old Thumler's Tumbler from your childhood, a good cleaning, a few drops of oil, and a new belt will likely make it run as good as new. Just follow our cleaning and oiling instructions. Your children might be delighted to be using the same tumbler that you enjoyed as a child.

    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 hundreds of barrels of rocks and is still going strong. We have changed the belt a few times, changed the barrel once, and replaced the motor once using these replacement parts. You will not get that kind of service out of a "toy tumbler".

    Happy Tumbling!

    Hobart King
    Owner/Manager
    RockTumbler.com