12 INCH TROMMEL BUILD

[AzViper]

Images of the process of cutting, fitting, and welding the base frame. The three holes are the mounting hole of the Unistruct. I am using 3/8" bolts and locknuts. On the underside I enlarged the holes so that I could get a socket to tighten the locknuts. I did not want to use bolt completely through the tubing due to crushing the tubing. Its better to pull the Unistrut tight to the frame using the method shown.

 

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[DizzyDigger]

Your one hellofa fabricator Az...

 

[AzViper]

Your one hellofa fabricator Az...

Thanks Mike. Been building things all my life. Very seldom do I buy when I know I can build better. Had I not lost my connection of a sheet metal shop I would have built my drywasher. My buddy lost his shop due to a nasty divorce. The trommel is slowly coming together. Working on it in my free time. Keith

 

[AzViper]

 

[Goodyguy]

Excellent Build!!!

Superior welding.
I suppose you are planning on welding a back flow preventer ring onto the front end of the drum?
I've seen diy's that overlooked that step. Even though the exit end of the drum will be lower than the front end, a slurry will still manage to run out the front end making a mess of whatever is underneath and possibly even loose some gold in the process.

Just my 2 cents
GG~

 

[jcazgoldchaser]

Excellent Build!!!

Superior welding.
I suppose you are planning on welding a back flow preventer ring onto the front end of the drum?
I've seen diy's that overlooked that step. Even though the exit end of the drum will be lower than the front end, a slurry will still manage to run out the front end making a mess of whatever is underneath and possibly even loose some gold in the process.

Just my 2 cents
GG~

Very good point, I'm not sure if the internal spiral would completely eliminate the need for one.

Watch this video to see material coming out the wrong end!!!!!

1:58, 2:35, 2:42, 3:48, 3:56,


{edit} watching a few more of his videos, I had the thought that if your funnel (thingy that catches the classified material) ran all the way up to the base of the hopper (thingy where you dump the dirt in), you'd also catch that backwash (stuff coming out the wrong end).

 

[Goodyguy]

That video certainly showcases my point. I believe it's easier to do it right the first time than to have to do it over.
I once saw one that had the slurry spilling all over the engine!

Doubtful the spiral will totally (if at all) eliminate back flow out the front end of the drum, mostly due to the surge of slurry as water and material is introduced to the already fluidized drum from the hopper.

And yes you could add a sheet metal trough to send the slurry down to the sluice, but the ring would eliminate that need plus the trough may get clogged unless you added a water source to it.

GG~

 

[KevinInColorado]

Keith does the cool down period = the time to enjoy a beverage? ;-)

 

[Clay Diggins]

Nice work Keith!

 

[AzViper]

Excellent Build!!! I suppose you are planning on welding a back flow preventer ring onto the front end of the drum?
GG~

GG I do just undecided how much of a ring. I want as big of an inlet as possible. Thinking of a 1 inch ring.

 

[Goodyguy]

1" should be fine.
That's what I used on my 15" drum with no problem.

GG~

 

[AzViper]

1" should be fine.
That's what I used on my 15" drum with no problem.

GG~

Will cut the back flow preventer from 1/8" flat plate using a template and cut it with the plasma.

 

[greenerlumber]

"Will cut the back flow preventer from 1/8" flat plate using a template and cut it with the plasma."

Dewd!! Next time I'm in Cali gonna look you up......I wanna come and just "play" in your shop!! LOL.....
Nice Freekin' Rig Buddy!
RP

 

[AzViper]

"Will cut the back flow preventer from 1/8" flat plate using a template and cut it with the plasma."

Dewd!! Next time I'm in Cali gonna look you up......I wanna come and just "play" in your shop!! LOL.....
Nice Freekin' Rig Buddy!
RP

Well I am in Arizona... I believe your a woodworker. Here is a circle cutout jig I made to cutout holes for cup holders on poker tables. The router pivots on the 1/4" pin. and the size of holes are adjustable. This is what I will use to cutout the template for the back flow preventer. Also the CNC router in action...

 

[goldenIrishman]

That thing looks awesome Keith! You're doing a great job on the Trommel and from what I've seen so far it's very well thought out. Don't you just love it when you can score parts like the bearings for the rollerblade wheels like that!!! Your use of unistrut is great too. It never hurts to have some adjustment room built it. Can't wait to see it in action out at the gulch. I'll e-mail you the map info we were talking about earlier.

Jeff

 

[AzViper]

Decided to try to work on the top side of the trommel. Kinda undecided if I want the two top side rail to be within 1.5" below the top of the cylinder so that I can incorporate the cross tube that will support the spray tube or have the side rail much lower. With the spray bar running the length of the trommel the cylinder will not be removable. To transport the trommel to the field will require to strap the cylinder to the frame. If I make the side rails lower will require me to weld uprights at each corner to support the cross tube at each end and make 16 - 45 degree cuts, more welding and grinding.

 

[jcazgoldchaser]

Initially I was going to suggest a template which allows the outer diameter with an offset to cut the inside diameter first.

But then I was thinking of the circle cutters for routers and torches and thought you could make a circle cutter out of a piece of strap and drill 2 holes for the outer/inner diameter and a small hole to rotate about the center.





You could get fancy with a magnet or clamp down plate for the center point



But I would just drill 1/4" hole for the center. Use a 1/4" bolt to hold the jig to the plate.

Then I would cut the outside diameter and STOP. Make sure it fits the trommel. You can adjust the outer diameter down with a grinder, using the same center hole to rotate the plate until the blank fits the trommel. Then go back and cut the less critical inner diameter. You can adjust it when the trommel is running.

 

[AzViper]

I decided to cut and weld while keeping the side rail lower. Little more work but worth it. Helps having a saw that cut true 45 degree cuts.

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[jcazgoldchaser]

I decided to cut and weld while keeping the side rail lower. Little more work but worth it. Helps having a saw that cut true 45 degree cuts.

.... and now yer just showing off...

Hard to tell from some of the shots, but I assume you're watching the chain clearance to the frame and scooter wheels.

 

[AzViper]

Hard to tell from some of the shots, but I assume you're watching the chain clearance to the frame and scooter wheels.

Plenty of room for both. Sprocket is 14.69" and the inside frame measures 15.5".

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