Speed up your gold processing work and increase gold recovery with the Mountain Goat Portable Trommel. This machine is aptly named because it can eat almost anything and is light enough to carry up a mountain! This machine is a real workhorse -- it can eat up as much as 2 yards of placer gravel and spit out as little as 10 pounds of concentrates in only 8 hours! Scroll to bottom of this page to read 2016 Field Test review.
The Mountain Goat Gold Trommel is a reverse helix system built on the same principle as the huge mining trommels used by large placer mining companies all over the world, but this is light (16 lbs) and portable, so one person can carry it out into the field. It is a miniature version of the huge trommels used by most major placer mining companies for the last 100 years. It is not to be confused with gravel pit trommels, though, which are designed to classify gravels.
The 4-inch Mountain Goat Trommel is very efficient because the spiral riffles inside of the tube turn and bring the heavy materials up to the high end of the tube while allowing the lighter materials to flow out of the back of the tube as tailings. This system makes the trommel self-cleaning, which eliminates the need to break down for clean-up as is necessary in sluice box type equipment.
The spiral riffles in the trommel tube are .25 inch deep and spaced .75 inches apart. We suggest your placer material be screened to .5 inch or less. There is a nugget trap at the low end of the tube which should be checked regularly for nuggets larger than .25 inch. Do not put rocks larger than half inch into the hopper because the larger rocks can jam the riffles against the spray tube and cause you to have to shut down to clear the jam.
Metal retractable legs adjust to 3 heights (see example below). Handle is molded into the trommel body.
The Mountain Goat can be used directly in a stream and is a very sturdy machine designed to take a lot of wear and tear! When using the Mountain Goat Trommel away from a running water source, we suggest you purchase a concrete mixing tub (the large size) and a bucket from your local home improvement store such as Home Depot or Lowes. The taillings bucket must be emptied before overflowing to keep gravel out of the water supply. You should also slip a sock over the pump to help keep the the spray system from clogging up.
- Length: 32 inches with hopper installed
- Width: 16 inches at bottom
- Height: 24 inches with adjuster legs
- Weight: 16 pounds
- Spiral Barrel: 4 inches in diameter
- Power: 12-volt battery NOT included
- Pump: 750 GPH INCLUDED
- Capacity: 2 yards per day
- Water Requirement: 5 gallons
- Motor Starting Amperage: 4
- Motor Running Amperage: 3
- DC Voltage Required: 12
- Pump Starting Amperage: 3
- Pump Running Amperage: 2
- Step-by-step instructions & Trouble-shooting tips shipped with trommel
We recommend you use a 12-volt battery with at least 17 amperes or more, which will run the machine about 3 hours at the right speed. The larger the battery, the longer the machine will run at the right speed. Always make sure that the red clip is on the positive (+) side of the battery. If you revers the clips, the barrel and the pump will turn backwards and no concentrates will be generated. It is not recommended that you run the trommel directly from a battery charger without a battery in the circuit. The trommel is designed to operate on 12 volts, but most battery chargers give out 18 volts, which will cause the Mountain Goat to run 150% the normal speed and kick out the material too fast to be concentrated.
TIPS: Use a wetting agent in your water supply to prevent fine gold from floating out into the tailings. If you are running oily beach sand, add a tablespoon of 409 cleaning solution to your water supply.
The Mountain Goat Gold Trommel is shipped via UPS Ground in the continental USA. Includes a manufacturer's 1 year warranty against defects of materials and workmanship for a period of one year from the date of purchase. The Mayfair marine bilge pump that is INCLUDED with the machine is covered by a separate warranty from the manufacturer. Warranty info. is shipped with each machine. FREE SHIPPING in continental USA! Larger trommels here.
EXCERPT FROM FIELD TEST REVIEW conducted by Kevin Hoagland, host of the GPAA-produced TV series Gold Trails, appears below. Be sure to read the complete Field Test published in the November/December 2016 issue of Gold Prospectors magazine or download the 6 page .pdf here.
"... The Mountain Goat Trommel is not new to the prospecting industry by any means. Invented by the late great Angus Niccolls, it has a long history of excellent gold recovery and easy of use. It will handle .5 inch minus material with the optimal recovery being material that has been classified to .25 inch. It’s best to use wet material when you use a wet system such as a trommel. It has been aptly named the Mountain Goat because “it eats anything and goes anywhere.”
The Mountain Goat is a variant of the Archimedean Screw, which is a tube surrounding a rotating screw used to pull a column of water up a grade. This makes it possible to easily lift water. In the Mountain Goat, the outer tube is lined with the screw, and as gold-bearing material is stratified by a stream of water and run through the tube, the heavier gold-bearing material is deposited into the reverse screw and brought to the top of the unit. The lighter waste material is continually washed and pushed through the unit into the tailings.
In other words, when material enters the hopper, the gold goes one direction and the water goes the other. It’s really no different than huge commercial grade trommels, except that the Mountain Goat does all of this in a unit that weighs less than 20 pounds, and recirculates about 10 gallons of water all day long. And if set up properly, the manufacturer says it can handle about two yards of material in a long day of running.
The Mountain Goat is cleverly designed. It’s compact and almost completely assembled when you receive it. The carry handle is molded into the unit, making it easy to transport (especially if you are riding a quad or other such vehicle). The trommel tube is pre-mounted to the unit with the nugget trap installed, needing no further assembly. The legs are collapsible and can be set to two different heights. Plus, the front legs are further adjustable to allow you to fine tune the unit to the material you’re working.
The pump is 12-volt, and the flow rate was chosen to offer the best recovery possible. It is recommended that you use some sort of filter on the pumps inlet side to assure that trash is not drawn into the system where it can cause clogs and lost time. The recovery trap sits on the unit and does not require any mounting tools. The hopper slides into the trommel and uses wing nuts mounted to stabilizer bars that quickly connect the entire assembly together. Set the Goat in a large tub if you’re using it as a recirculating unit, add water, hook it up to a battery and you are almost ready to run material.
Before you use it for the first time, or if it has sat unused for a while, be sure to clean the unit with hot water and a little plain, unscented dishwashing soap. Hook up the unit and allow the soapy water to do its job of removing the release agent that comes on just about any molded product. Sponge down all surfaces exposed to water and the outside of the unit, too. This simple cleaning step can prevent gold loss. You might want to clean the machine outdoors as the soap bubbles end up everywhere!
As you use the Mountain Goat, continually test the tailings. You should not see any gold. If you do, you may need to increase the angle of the unit by turning the screws on the front legs. It’s a bit of trial and error, just as it is when setting up a sluice in a stream. The Mountain Goat can be paired with the Desert Fox for a complete two stage concentrator and final recovery unit."
Download the complete Mountain Goat Field Test here (6-page .pdf).