Screening Plant Project

[MJPetersen]

Mark,

That looks very nice. That is a job well done!! It looks like you barely have enough lift to carry it. Now Cindy can have her flower beds with nice topsoil.

Mike

 

[SkunkWerX]

That is a beauty!! Good job!
Gives me some great ideas to use for mine.

What is the angle of the shaker tray?
Is there any reason you picked this particular angle?
What would you do differently, if anything, if you had to start over?

 

[akpilot]

[What is the angle of the shaker tray?
Is there any reason you picked this particular angle?
What would you do differently, if anything, if you had to start over?[/QUOTE]

The tray is on it's middle( 24,30 & 38 degree) setting about 30 degrees. I would like to say there was good math or science behind that decison, however, I'm not that smart I think it depends a lot on the material your screening and the size of screen your using, I am losing a small amount of product of the back of the screen, at that setting so today I think I will move it down to the 24 degree setting and try it to see if it makes much of a difference.
What would I do differently? it's a little tall, I would probably shorten it about 6-10 inches as is, I put a scoop of dirt for the front tires to run up on. the screen i'm using now is welded to the frame, so somday I will beef up the frame and make it so I can bolt on different screens, but all in all i'm pretty happy with it. I added a pic to show the angle adjustment a little better

 

[SkunkWerX]

Thanks akpilot, good info and answers. Please know my questions relate to my possible build, I think you did a great job and it looks like it does a great job.

I was looking at building a bed that would accept 1 or 2 screens, and make them removable, interchangeable as well.

From what I am hearing and thinking, it makes sense that the steeper the angle the quicker it will screen, but as you say, if the product moves downward to quickly you can loose the product over the edge before it's `100% screened. That's why I asked if you had any thoughts behind the angles.
Please let us know how it does at the lower 24 degree setting.

I like the angle adjustment mechanism. I was tossing around an idea that would give a variable angle from about 10 degrees up to like 40 or 45 degrees?? Or maybe some fixed settings at 10,20,30 and 40 degrees?


Last question: Where did you get the springs?
What is their diameter, length and estimated deflection when a load is dropped on them?

Car coil springs seem like they may be too stiff, as my screener will be smaller than yours. I have a smaller 4 foot wide bucket. I'm thinking maybe some dirtbike or ATV coils? Does this sound like in the right ballpark?

I'll be screening anything from Compost at the light end to run-of-the-mill Fill dirt with maybe softball sized rocks at the heavy end of things.

Again, I think your screener turned out very nice.

 

[akpilot]

Thanks for the nice comments!

I screened 10-15 yds today at the flatter screen setting (25 because it's not perfectly level) seem to work well, it didn't seem like I lost as much off the back, however it's not all good I'm getting more small rocks in the final product, which for what i'm doing right now is OK. When I start screening for the garden soil (dirt peet mix) I think I will go back to 30 and maybe suspend a piece of belting with the other end laying on the screen to help break up the peet.

The springs are car springs(rear springs off a front wheel drive car), because it's what I had, I think ATV springs would work great. You don't want it so soft that it bounces a lot, that could cause the belt to come off. When the plant is running the springs barely move, it's when I drop a full bucket is when they move, they do a real good job isolating the frame from the viberation. I worried about the springs being to stiff, but now I don't think it's worth worring about.

I like the idea of two screens, the main problem as I see it, is seperating of the product. On large plants they have hoppers and conveyor belts to maintain seperation, but on this size it would be more difficult. I do like the idea though.

As far as angles, 10-40 degree would be a real wide range and make your plant very versitile.

 

[SkunkWerX]

Mark,

Here are just a couple of thoughts, based on your actual usage and comments.

Belt tension: When I first read your issue about the belt, I went to the drawing board.
Install an idler pulley down near the motor mount. Put it on a pivoting arm, and use a spring to keep tension on the belt. As the belt deflect, when the springs compress, the idler arm will take up the slack. Hope this makes sense.
It's the same idea as an idler on a 2 or 3-spindle mowing deck.

Separation:
With two screens, I was going to place an outlet plate at the end of the top (coarse) screen so they fall well clear.
Let's say the second screen would be approx. 1" sized stuff? I would end that screen a few inches short of the coarse screen, and place a steep "gutter" taking that material off to one side.

Picture the Coarse screen creating a waterfall, and the gutter running perpendicular, underneath the waterfall? The steel gutter would be suspended from chains, that hang from the edge of the 2nd screen, which would make the gutter vibrate as well, causing the smaller material to tumble down the gutter? It might take some trail an error to develop something that works. Or, as a fall back, just make another divider wall.

 

[akpilot]

Mark,

Here are just a couple of thoughts, based on your actual usage and comments.

Belt tension: When I first read your issue about the belt, I went to the drawing board.
Install an idler pulley down near the motor mount. Put it on a pivoting arm, and use a spring to keep tension on the belt. As the belt deflect, when the springs compress, the idler arm will take up the slack. Hope this makes sense.
It's the same idea as an idler on a 2 or 3-spindle mowing deck.

Separation:
With two screens, I was going to place an outlet plate at the end of the top (coarse) screen so they fall well clear.
Let's say the second screen would be approx. 1" sized stuff? I would end that screen a few inches short of the coarse screen, and place a steep "gutter" taking that material off to one side.

Picture the Coarse screen creating a waterfall, and the gutter running perpendicular, underneath the waterfall? The steel gutter would be suspended from chains, that hang from the edge of the 2nd screen, which would make the gutter vibrate as well, causing the smaller material to tumble down the gutter? It might take some trail an error to develop something that works. Or, as a fall back, just make another divider wall.

I was going to install a idler pulley, until I started looking at the geometry of the belt and decided the idler would be plan "B". When the screen deflects, it doesn't come straight down, it angles forward and down because of the rear pivot points. that is why I mounted the motor where I did. Ideally if the drive pulley was inline with the lower pivot point the belt would never become loose. Mine seems to be close enough that I haven't had a problem with it yet.

I like your ideas for for the dual screens, but remember you won't have a lot room on the low side of the screen, mine is about 4' above the ground, so by time you extend top outlet plate you my run into some problems. Measure your bucket in it's fully raised and dumped position then figure your angles, to give you an idea on how much room you will have.

 

[SkunkWerX]

I was going to install a idler pulley, until I started looking at the geometry of the belt and decided the idler would be plan "B". When the screen deflects, it doesn't come straight down, it angles forward and down because of the rear pivot points. that is why I mounted the motor where I did. Ideally if the drive pulley was inline with the lower pivot point the belt would never become loose. Mine seems to be close enough that I haven't had a problem with it yet.

I also entertained the idea of running a double pulley at the lower pivot point, then another belt to the mid-point of the shaker tray, with the weighted flywheel.
In order to get a wide variety of angles, from 10 to 40 degrees, I think I will be ahead of the game to go ahead and design an adjustable idler pulley, so when the shaker tray is angle is adjusted, the idler can be tightended or loosened to compensate for the needs of the drive belt.

I like your ideas for for the dual screens, but remember you won't have a lot room on the low side of the screen, mine is about 4' above the ground, so by time you extend top outlet plate you my run into some problems. Measure your bucket in it's fully raised and dumped position then figure your angles, to give you an idea on how much room you will have.

Gotcha, I already know my max. dump height, and will be screening a yard or two at a time, probably not piling up yards of screened debris in a session.

It's all good stuff, your thoughts and ideas, I do appreciate you taking the time to share them! It's helped me sort through some of the planning hurdles.

 

[slicktierney]

Can you post the picture of your idler/tensioner. I added a tongue and axle

 

[DRL]

Great looking screener. Working on an offer right now for some property that I will need one of these for. It has lots of gravel and sandy gravel so I should never have to buy gravel. What I was wondering is how I could get clean sand out also, for concrete work.
Years ago I drove tri-axle dump trucks from the creek to a concrete plant. We would just load up from the creek bank( yea, I know, can't do that any more) carry it to the plant and they would separate the gravel and sand and wash the dirt away. Like a dummy I never did take the time to see how the sand washer worked. Does any one have any ideas for a small simple DIY sand washer that would be a mate for this size screener. Screen the gravel out of the material then run the fines through the washer to separate the sand from the dirt.
Thanks for sharing your build with us, it looks like it does just what it was built for.
DRL