Hand Dredge

Intro: Hand Dredge

A hand dredge, also called a gold sucker, is basically a pump that will allow you to suck up material. They allow you to suck up material in hard to reach places, such as under rocks, and in crevices. Hand dredges work extremely well if you are prospecting for gold as they allow you to quickly move lots of material.

Parts Needed:

PVC Cement
30" 1-1/4" PVC
36" 1/2" PVC
1x 1-1/2" ABS Wye Fitting
1x 1/2" PVC Slip Cap
1x 1/2" PVC Threaded Cap
2x 2 1/4" PVC Slip Cap
3x 1-1/2" x 1-1/4" PVC Bushing
1x 1/2" Slip to Threaded Adapter
1x 1/2" Foam Pipe Insulation
1x 1/2" Elbow
1x 1-1/4" x 1/2" Reducer Coupling

Cost:

I purchased all of the parts new for just under $23. I did not have to buy any of the tools.

Tools:

Dremel or Sand Paper
Scissors
Pipe Cutter or Hack Saw
Drill

Disclaimer:

This dredge is not my original design, it's based on this: http://www.youtube.com/watch?v=YCozzarSk5A

Please note I am not responsible for anything you do, so please only use my instructions as guidelines. Use proper safety equipment and common sense. Also check with local laws to make sure you're allowed to use a dredge in your local area.

STEP 1: Step 1 - Drill Cap, Sand 1/2" Adapter

Find center of 1-1/4 PVC Cap and drill a hole that is 5/8" in size. Slightly larger than the 1/2" PVC pipe. It doesn't have to fit tightly, it's really just for aesthetics, and to keep the handle from pulling all the way out.

The easiest way to find the center of the circle is to place a square over the circle, lining up the the point on the edge of the circle. Then mark the spot where the square goes outside of the circle. Draw a line between two marks. Repeat this again by moving the square part way around the circle and drawing another line. Where the two lines intersect is the center of the circle.

For more in-depth instructions:
http://www.mathopenref.com/constcirclecenter2.html

Next you'll want to use a dremel or sand paper to sand the PVC Bushing (1/2" slip  to 1/2" threaded) so it can fit inside the 1-1/4" pipe.

STEP 2: Step 2 - Cut PVC to Length, Create Seal

You'll need to cut the PVC accordingly:

24" 1-1/4"
6" 1-1/4"
6" 1/2"
24" 1/2"
6" 1/2"

Once done, cut about 1/2" of the pipe insulation to create the seal. Remove the plastic from the insulation and glue the two pieces together. 

STEP 3: Step 3 - Dry Fit

Dry fit the pieces accordingly to make sure everything is the size you want and that you have all the parts needed. Make sure the ABS Wye connector has both ends facing down with the other end connecting to the pump section. That way as material falls down, it can collect inside the part with the cap.

To create the pump section, take the 24" long 1/2" pipe and pit the 1/2" elbow on one end. Then put the 1-1/4" cap with the hole drilled in it over the pipe. Then, place the 1/2" slip to 1/2" thread bushing onto the end. Take the pipe insulation and place it over the threads, then screw on the 1/2" cap. This creates the seal needed for the pump. On the other end, take the 6" long 1/2" pipe and connect it inside the elbow. Then place the 1/2" cap over the pipe. This is the handle. 

To create the collection piece, take the 6" long 1-1/4" pvc and place the undrilled 1-1/4" cap over on end. The other end is then connected to the 1-1/4" to 1-1/2 bushing. This is then inserted into the 45 degree part of the ABS Wye connector.

To setup the sucking piece, take the 6" long 1/2" pvc and insert it into the 1/2" x 1-1/4" bushing. Then insert that into the 1-1/4" x 1-1/2" bushing. Then, insert that into the bottom of the ABS Wye connector.

If you can find a 1-1/4" wye connector, then you could leave out the 1-1/4" x 1-1/2" bushings, but I wasn't able to find one. hence why I used so many bushings. 

Finally, insert the 24" long 1-1/4" pipe into the top of the ABS Wye connector. Then insert the handle assembly into it. There should be a tight fit. Connect the top cap where the handle bit is. That's basically it for the dredge. Now you'll just need to glue it together.

If you pull the handle up, you should be able to suck up water from the sucking end. If you hold your hand over it, it should feel some force when you pull the handle out. Or if you push the handle, you should feel air on your hand. This means the pump assembly has a good seal and is working correctly.

STEP 4: Step 4 - Glue Pieces

This step is pretty self explanatory though you won't want to glue everything together, just key parts.

Start by gluing the handle assembly together, the end cap, elbow, and 1/2 slip to 1/2 thread connector. Don't glue the cap on the handle assembly to the 1-1/4" pvc as you'll want to be able to take it apart to clean it out or replace the seal.

Once done, insert the handle assembly where the seal is at into the 1-1/4" pvc like you did in the dry fitting.

Next, glue the cap onto the 6" 1-1/4, then glue the pvc into the bushing. Do not glue the bushing into the ABS Wye connector. This is where material will collect and you'll need to be able to take it out to pan through your material.

After that, to create the part that sucks up material, glue the 6" long 1/2" pvc into the 1-1/4" to 1/2" bushing, then glue that into the 1-1/2" to 1-1/4" bushing. Do not glue this to the ABS Wye - you'll need to clean this out occasionally.

Then, take the 1-1/2 to 1-1/4 bushing and glue it into the top of the ABS Wye connector. Do not glue the handle/pump assembly into this bushing. Dry fit the handle/pump assembly, collection piece, and sucking end together and then it's complete!

STEP 5: Complete!

Your dredge is now complete. To suck up material, just keep the collection piece faced down and pull the handle to suck up water and material. As material falls back down, it will get stuck in the collection piece. Water will then drain out the end of the pipe. Keep doing this until you think the collection piece is full.

Then loosen the collection piece and pour it into your gold pan. Rinse then connect it back together and repeat!

Good luck with finding gold! If you have any better ideas, please feel free to share them.

Comments

[ggmex4wd5sp]

How much sand can this process move? I live on a lake and have low spots it the yard that need to be filled. I have a large centrifugal pump to move the water. Would I be able to suck enough sand / mud from the lake to fill the holes or would I just be better off with a shovel when the water is low? Thanks

[kretzlord]

Nice setup, how does it work for sniping in the cracks? Found any color?

[flyingpuppy]

Is the idea something like this hand pump water gun I made? I mean, does the valve system work similarly?

[Sermos]

I didn't use any valves. Basically as you pull the plunger out, material is sucked up and goes into the pump chamber. When you release the pressure, material then falls back down, but instead of going out the end that sucked up the material, it falls down into the collection chamber due to gravity (which is why it has to be at at the bottom).

I was thinking of using one way valves like you did, and using a hose instead of a collection chamber, so I could pump the material from the crevices directly into a sluice or gold pan but I should be able to easily modify the current system to work with valves.

I like your idea on the valves though!

[flyingpuppy]

Ah! NOW I see how yours works. BTW, I need to copy your plunger design. Mine leaks a bit out the top.

[Sermos]

When I was at the river last time my seal actually broke and I forgot to bring an extra one, so we ended up using a foam insert of an old shoe. I cut a small circle in the middle to fit onto the pipe and cut it into a round piece then screwed the cap over. When I pushed the plunger into the pipe it fit really snug and had excellent suction. Just something to think about :)

[flyingpuppy]

And that's how inventions are born & perfected--necessity.

[fishrmn100]

Also went to Shasta College in Redding and would love to see a video! I do really enjoy gold panning and intend to go back to it, once I'm retired, shortly.
I'll try this, even without a video. GOOD WORK!!

[Silvester10528]

I didn't read the instructions, just looked at the pictures, so please bear with me in case you covered this...

At first I was wondering why you didn't have any screening to limit the size of particles and rocks, but after thinking about it for a few seconds it makes perfect sense... the 1/2" in tube prevents anything larger than ball bearing size from coming, so you're mostly just gettting sand and small flakes...


Makes me wish I were in gold country!

[Sermos]

The 1/2" tube does limit the size of the material coming in, and does occasionally get blocked, but you could easily swap out the tip for a larger piece of pvc (up to 1 1/2" though the actual vacuum power won't be as strong).

[uzziah0]

How about a paragraph at the top the states EXACTLY what this will do, why would I want to make one, or what you are doing with it.
Otherwise, looks great.

[rhino]

Better spray paint the end orange so some cop does not shoot you. Great design. I use the suction stick from Sam Raddings Book of Plans. This works on a similar principle. I love your design for the drop part that holds the gold. Hooray for PVC! I need one that works without water as I am working dry washes.

[canida]

Cool! This looks similar to PVC dredges I've seen people use for sucking up clams on the beach or mudflats, though theirs were made with wider PVC.

[snotty]

Yes! This one's screaming for a video. I'd love to see it in action :)

[Silvester10528]

Ditto that!!! I was definitely hoping to see a video!

[Sermos]

I'll try to record a video next time I go to the river, I forgot my camera last time. :)

[Schmidty16]

man i like ur idea i wish there could be more gold mining ideas on this website

[sodiumcanine]

Reminds me of the Dayze up at Shasta College in Redding, we used to pan
up at our spot camping on weekends for beer and food money in the 90's, could not use a dredge or fish on The Sacramento from the Chem Spill (trainwreck) but could bring up black sand with SCUBA gear ( Hope I did'nt Dame My Bramage..twitcth-twicht !) Our "Assayer" in Redding seemed to give us let than
actual worth for our flake and few nuggets.(break a point off a #2 pencil, About all we found) At today's Gold value, would have lived like Kings ! ( Teriyaki Burgers for
the whole class at the Cafeteria !) Fun Times!

[bobby sissom]

Voted high and now following,more gold finding idea please,please,pretty please,i like shiny gold.

[rimar2000]

A video? Please...