Comments on: HomeMade Rotary Trommel Screen

By: KEN BANGERTER

KEN BANGERTER — Mon, 26 Jul 2010 03:07:39 +0000

40×80 YARDS 1 FOOT DEEP TOTALS 1067 CUBIC YARDS, ABOUT 90 TIMES WHAT I ENDED SCREENING. I DID ALL THE SHOVELING BY HAND, MOVING THE MATERIAL BY GARDEN TRAILER AND LAWN TRACTOR, PLUS THE POWERED WHEEL BARROW I ENDED UP BUILDING. THERE WAS NO RUSH IN COMPLETING THE JOB, SO MY ROTARY SCREENER WAS FINE. IT WAS ALSO USED FOR MANY HOURS BY TWO OTHER HOMEOWNERS WITHOUT A CHANGE OF THE 1/2″ MESH SCREEN.

FOR A 1000 CUBIC YARDS, IF I COULDN’T RENT A COMMERCIAL SCREENER, AND I WANTED A SHORTER COMPLETION TIME,I WOULD HAVE BUILT A COMMERCIAL STRENGTH SCREENER WITH LARGER WHEELS FOR THE DRUM SUPPORT WITH A VERTICAL AXIS WHEEL TO KEEP THE DRUM IN PLACE. I WOULD HAVE USED USED 1/2 INCH EXPANDED METAL FOR THE SCREEN, LONGER BARS SEPARATING THE DRUM HALVES, AND A FEEDER CHUTE THAT COULD ACCEPT MATERIAL FROM A BACK HOE OR FRONT LOADER.

By: Ian

Ian — Mon, 26 Jul 2010 00:32:23 +0000

I love this idea of a rotating trommel as I have a large area of garden to clear of weeds, broken glass, stones and bits of cars in our new house’s garden. How can I improve on this to help clear such a large area to a depth of around 12 inches?
The garden is 80 yards by 40!

By: KEN BANGERTER

KEN BANGERTER — Tue, 23 Mar 2010 03:53:38 +0000

MY RED ROTARY TROMMEL, SHOWN, IS POWERED BY A 1/4 HP 120 V INDUCTION MOTOR, THE 55 GALLON DRUM SPEED IS ABOUT 27 RPM, GIVING A SCREEN SURFACE SPEED OF ABOUT 175 FEET PER MINUTE. USE BELTS AND PULLEYS TO REDUCE THE SPEED, RATHER THAN REDUCING THE MOTOR SPEED ELECTRONICALLY. DRILL MOTORS COULD BE USED, BUT THE MOTOR NEEDS SPEED TO FAN COOL ITSELF.

THE UPPER MOTOR, WHOSE PULLEY DRIVES THE DRUM IS A 1/3 HP DRYER MOTOR, HOWEVER, IT TURNED THE DRUM AT ABOUT 55 RPM, FAST ENOUGH TO LIFT THE STONE NEARLY TO THE TOP, WHEREUPON IT FALLS AND HITS THE SCREEN. THIS IS VERY NOISY AND CAN DAMAGE THE SCREEN.

CLOTHES DRYERS RUN THAT SPEED TO ALLOW AIR TO GET TO EVERY AREA AS WELL AS TO FLUFF IT. I WANTED A SPEED THAT WOULD RAISE THE STONE ABOUT HALF WAY UP, SO IT WOULD SLIDE DOWN AND GRIND ANY CLUMPS OF DIRT. THE LOWER SPEED ALSO REQUIRES LESS POWER.

IN IT’S FINAL FORM, THE 1/3 HP MOTOR IS USED AS AN IDLER SHAFT AND IS DRIVEN AT ABOUT 1/2 SPEED BY THE 1/4 HP MOTOR.

IF YOUR DRUM IS LARGER THAN THE 55 GALLON DRUM, YOU MIGHT NEED MORE THAN 1/4 HP ONLY IF YOU ARE FEEDING THE DRUM FASTER THAN ONE MAN SHOVELING.

MANY COOLER MOTORS ARE SHADED POLE MOTORS THAT ARE ELECTRICALLY INEFFICIENT, HAVE LOW STARTING TORQUE AND NEED TO RUN AT FULL SPEED FOR THE COOLING FAN TO MOVE ENOUGH AIR TO COOL IT IF RUNNING AT FULL LOAD.

By: DAVE BARKER

DAVE BARKER — Mon, 22 Mar 2010 19:39:24 +0000

I am incredibly impressed with this rotary trommel screen. I have built my own (with a few modifications that makes it a little more heavy-duty and a little safer) but I am not good picking motors it seems. What’s a good HP motor to use? I can dial down the speed with a dimmer switch if I go over, but I have burned out a used 1/3 & a 1/2 HP swamp cooler motor so far.

By: KEN BANGERTER

KEN BANGERTER — Tue, 12 May 2009 22:23:28 +0000

I FORGOT TO MENTION THAT BY SIMPLY LOOSENING THE BELTS AND SLIDING THEM OFF THE DRUM, THE DRUM COMES OFF SO THE MACHINE FITS NICELY IN A VAN.