Introduction: Powered Wheelbarrow Trommel
A great way to separate rock from dirt. It's perfect for gardens or in my case landscape rock!
I needed to install a french drain to redirect the rain from the front of my house. The problem was that my house is surrounded by rock beds! I ended up building a powered wheelbarrow trommel to save me from separating the river rock from the good dirt by hand. The trommel will also come in handy for getting all those pesky rocks from my wife's garden. The most novel thing about it is that the trommel sits on top of my wheel barrel so that dirt is dispensed right in the wheelbarrow for easy transportation. Oh, and I built the thing for less than 90.00.
Step 1: Building the Frame and Track
Dimensions
If you'd like to build one for yourself, you'll have to make up the dimensions as you custom fit the frame for your wheelbarrow. Rather than describing whats in the pictures, I tried to just take good descriptive pictures so that you could copy the design from them.
Specs for the basic parts
- Gear reduction motor (125 rpm, 1/10hp, 12v, 12 amp)
- 3/4 inch pulley with 5/8 inch bore, but any size pulley will work
- 10 amp manual battery charger
- 1/4 or 1/2 inch wire mesh screen fencing from any hardware store
- The tops of three 5 gallon buckets (two for wheel tracks and one for pulley)
- 8 castor wheals that fit in the track of the bucket rims
- (optional) Rubber floor mat to use for funneling the load into the trommel drum
Tips
If you are going to use a garbage can to catch the rocks as they come out of the trommel, you'll find that the wheelbarrow will tip backwards. I shifted my wheelbarrow's legs back 6 inches. The easiest way to keep the cross plate that gives the legs their stability is to turn the legs around before remounting them. If you'd like to save 15 or so dollars you could forgo the mesh screen and bolt two 5 gallon buckets together and then drill "a lot* of 5/16 in holes in buckets to simulate a screen. It works. I tried it, but it won't perform as well as the mess screen. Get a wheelbarrow with two wheels! I overloaded the wheelbarrow a few times and almost it.
Step 2: Creating the Drum
I moved to a new house with lava rock and found myself wishing the wire drum was 1/2 mesh than 1/4. The orange drum's 1/4 square mesh worked really well for separating river rock from dirt. This blue drum with 1/2 inch mesh is more aggressive. It will let more dirt through, but if you are confident that you don't have any pebbles in your pile you are good.
Shopping list
- 3 five gallon buckets
- 1 five foot role of wire weld fencing
- 28 half inch pan head screws (the fatter the head the better.)
- Depending on how fat the heads of your pan head screws are and how big of holes your fence has you may need to get 28 washers to help hold down the wire.
Steps
- Cut two of the buckets about 1.5 inches below the bottom most channel. I used a sawzall, but a hacksaw works too.
- Cut the third bucket just below the bottom most channel. Use this one for the middle of the drum.
- Slide the middle bucket rim onto the drum. Then slide the two other bucket rims onto the ends of the fencing.
- Starting with the outside bucket rims, screw the fencing down to the inside of the first rim.
- Once you have one rim on, dry fit the drum on the trommel and line up the other end rim with the track wheels. Then screw the fencing down to the second rim.
- NOTE : Remember this thing has to turn. Make sure that you screw the rims on straight so that your wheels run smoothly in the channels. Use washers with the screws if the heads of your screws are not wide enough to grab a hold of the fence.
- Once you are confident in how the drum turns, line up the middle rim with the pulley from the motor.
- Attach the belt to the pulley.
- Screw down the fencing to the middle rim with just four screws. Then give it turn using the belt. Adjust the positioning of the rim until the drum turns with ease using the belt. It should not seam like it struggles. If the drum turns like it's an off balance egg then you've got some more tuning to do.
- Once the drum turns like a dream, screw fence down to the middle rim with the remaining screws.

Finalist in the
Wheels Challenge
18 Comments
7 years ago
Nice design. Where did you source your motor?
Reply 7 years ago
I got it on ebay. It was a motor from one of those motorized shopping carts.
7 years ago
Sure thing. Here you go.
7 years ago
Hello, I hope you're still checking the comments on this post. Do you still have this trommel? Is it possible for you to take a picture of the pulley itself? idk anything about pulley so idk what that 3/4" you're talking about is :( And this is the last item I need to make this. Thank you!
8 years ago on Introduction
I've been looking around for cheap Bicycle rims to make the Popular Mechanics trammel, with no avail... I didn't even think of using Painters buckets, great idea!! Mine will be a little longer and have a greater pitch to it, so I can work more material. But your idea for a wheelbarrow mounted unit is smart engineering!4
Reply 8 years ago on Introduction
All those are great ideas. Bike rims would be ideal. I just had buckets lying around. So I went with the less expensive route. I'd thought of creating a funnel so that I could just drop the dirt in verses shovel it it.
I'm from Madison, WI. If you are looking for used bike rims, try Dream Bikes. It's a non-profit bike shop that deals only in donated, used bikes and gear. They hire from the Boys and Grils club to create opportunities for kids to learn how to sell or be mechanics. Anyway, the one here just got a large shipment of used rims. Call them up. If you aren't from the area, hopefully you can find a shop like it. They are a great organization to support
Reply 8 years ago on Introduction
I just moved to a new, smaller, city and haven't found the good spots for parts! Keep up the good builds
10 years ago on Introduction
I gotta ask, where did you source your 3/4" OD x 5/8" bore pulley? I have been looking for one, and I cannot find one for the life of me.
Reply 10 years ago on Introduction
Ace Hardware was where I got mine. They had a great selection.
11 years ago on Introduction
Very nice! I can't tell from the pictures, do you have the drum slanted, or how do you make the rock travel down and eject into the trash can?
Reply 11 years ago on Introduction
Good question. The drum is mounted level on the wood platform. The wheelbarrow is what puts it at an angle. I found that the longer the rock/dirt stayed in the drum the cleaner it got. So at times I used blocks to raise the back end of the platform so that it is slanted by about 5-10 degrees (the video shows no blocks because the wheelbarrow was already adjusted by the way it was positioned on the ground) . It's all about finding a good speed to angle ratio for loading the drum efficiently. The drum spins fast enough to move the rock through by the time I filled my shovel and was ready to load the drum again. Depending on your motor, if you find that it doesn't spin fast enough just put a bigger pulley on the motor.
11 years ago on Introduction
use it for gold mining dude get gold mmm gold fever
11 years ago on Introduction
Nice! Time to go to Alaska.. No guts.. no glory!
11 years ago on Introduction
I like it! Any idea how long it'd run on a car battery? It could be taken into the "field" and used for gold prospecting.
Reply 11 years ago on Introduction
That I couldn't tell you. There are too many variables to consider. The motor is actually rated for 12 volts and 12 amps. You could plug it into your car without a problem and just leave your car running to charge the battery which powers the motor.
11 years ago on Introduction
What a good idea!
Reply 11 years ago on Introduction
Thanks Rimar2000. It's saved me lots of time. I was able to move a 20X10 section of river rock in one day.
11 years ago on Introduction
What a good idea!