Trommel Barrel Cog

[y4k]

Am thinking of attempting a trommel build now that ive finally got my welder was looking through some old posts for ideas on gearing etc which i think ive got sorted out with pushbike cogs and chain but im stuck on actually turning the barrel and where to find a cog big enough to surround it. Obv the size of the barrel will depend on the size of the cog i can find, hope im making sense because im confusing myself as i type it haha but ive seen builds where the chain goes around and over the actual barrel which i imagine would be as easy as cutting the centre out of an existing cog and welding it to the outside of the barrel but the only cogs ive been able to find (motorbike sized) would mean the barrel would be fairly small. Im not looking to build something huge but maybe 20ltr bucket size...any ideas of where i could find a cog that size?

 

[AtomRat]

Get the cog to rotate a scooter wheel or something that the mesh can rotate on?

Old flywheel?

Use a band around the whole mesh?

Keep in mind to hold both ends of the rotating mesh to prevent it jumping off the system you make. Ive seen many where only near the gear is fixed

 

[AtomRat]

When your making a large ring or gear, remeber it doeant have to be one whole piece 360' around. You can make it out of 4 or 8 sections the same to join as a big ring

 

[AtomRat]

If chains are an issue, use pulleys and belts mabey too

 

[y4k]

Hadnt thought of using a smaller wheels to drive it AR, i like that idea. Picked up a heap of cheap wheels on ebay that id planned to mount on some sort of hinged bracket which would close over the barrel and bolt down to hold the barrell in place, if i could get drive to one of those might work, cheers mate

 

[y4k]

When your making a large ring or gear, remeber it doeant have to be one whole piece 360' around. You can make it out of 4 or 8 sections the same to join as a big ring

Had thought of trying to make 'one big cog' out of several but wasnt sure how it would go as i imagine it would be hard to get it matched up evenly and if it wasnt it would be jerky and the chain would probably jump off?? Im not that mechanically minded so im kind of winging it lol mostly reliant on what ive seen on other builds and friendly advice

 

[AtomRat]

Cool mate, have a look at pulley driven rock tumblers. One shaft usually rotates from main motor and a belt rotates the other. Barrel sits on top both rotators and then the barrel is held down with 2 clamps over the top half of the mesh

I think another way to do it with bike gears is weld a shaft off the gear centre that you then have rollers on or eccentrics and magneto.. oh sht..thats stationary engine

 

[AtomRat]

Yeah..im not a welder or much experience in these sorts of builds..im more a hack for now, but know a few designs.

If you can include a reverse helix spiral, your on the money

 

[y4k]

Yeah..im not a welder or much experience in these sorts of builds..im more a hack for now, but know a few designs.

If you can include a reverse helix spiral, your on the money

Im a shocker for taking the easy way out mate hence the trying to source a ready made cog, i fear a reverse helix spiral might be beyond me lmao. Is plenty of vids on utube showing the cog completely around the barrel and they 'appear' to be a single unit so must be out there somewhere....but definately like the sound of the smaller drive wheels so will keep searching for the elusive cog while working on the wheels theory and see which one reaches the finish line first.

 

[AtomRat]

Can u post a vid that shows the full cog mate, ill see if i recogise them

 

[limpalot]

Lay some chain around the barrel and have a drive cog on your motor.
Cheers LL.

 

[AtomRat]

Personally, i would prefur to roll it on wheels than use a cog / chain system as i like my fingers where they are.

Does this help at all:
http://www.google.com.au/search?q=t...off&hl=en&tbm=isch&q=trommel+build+chain+gear

 

[y4k]

Lay some chain around the barrel and have a drive cog on your motor.
Cheers LL.

Would it grip the barrel enough that it didnt slip? or would it need some teeth welded on the barrel?

 

[Nightjar]

Y4K,
Wrap a chain around the drum tack weld it in place then use gears to drive it.
Opposite to above photo.

 

[AtomRat]

Haha..yeah thats are better way lol

To prevent the slipping, use rubber

 

[y4k]

Personally, i would prefur to roll it on wheels than use a cog / chain system as i like my fingers where they are.

Does this help at all:
http://www.google.com.au/search?q=t...off&hl=en&tbm=isch&q=trommel+build+chain+gear

https://www.prospectingaustralia.com/forum/img/member-images/3111/1449095602_trommel_sprocket.jpeg

Yeah mate it all helps i might need to go back to the vids and look more closely its possible that they are infact made up of sections of cog instead of one larger one and i just couldnt see it because of the chain

 

[y4k]

Y4K,
Wrap a chain around the drum tack weld it in place then use gears to drive it.
Opposite to above photo.

I knew there would be a simple solution...did i mention im not very mechanically minded? Lol tks for all the input guys, greatly appreciated.

 

[AtomRat]

Having trouble keeping up with the thread there y4k lmao :lol: :lol:

Got plenty o answers!

 

[y4k]

Doesnt take much to confuse me AR lol that and i tend to make things alot harder than they need to be! My biggest problem now is there were so many good ideas i dont know which way to go...a fleet of Trommels perhaps?

 

[AtomRat]

The reason its taking me soo long to make a new sluice is because i want it fully designed on paper before building and make it as customizable as possible and able to clip on, clip off sections for each scenario i dig at. Trying to make a machine for all areas the best i can and keeping it light too.