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Rain, especially heavy rainfall or flooding, can “bring gold back” because it acts as a natural force that loosens and washes gold particles from the riverbanks and bedrock in mountainous areas, carrying them downstream where they can be deposited in more accessible locations for prospectors to find; essentially replenishing gold deposits in rivers after erosion from previous weather events.
When heavy rain occurs, the rushing water erodes the soil and rock along riverbeds, dislodging gold particles that were previously embedded in the sediment.
Since gold is a heavy metal, it tends to settle to the bottom of the riverbed, getting caught in crevices and behind rocks where water flow slows down.
Large flood events can significantly increase the amount of gold transported downstream, further replenishing gold deposits in certain areas.
So gear up and get ready for gold season!
You’ve GoT This!
There is so much more to reclamation dredging than just hunting for gold! Recent flooding has created a demand for cleaning out waterways, clearing out ponds, and dams, clearing boat slips and so much more! Ready to learn more? Read on!
—- GOLD PRICES ARE UP!!! —-
Let’s get you geared up for GOLD SEASON !
BE PREPARED!
A pool, a spa, a pond, all full. You see it time and time again in news reports of the aftermath of a devastating fire. With a Keene FireFighter you will have an invaluable tool to defend your property. Isn’t it worth the investment to have one and never need to use it? Don’t regret it, be ready instead.
Keene Engineering is very proud to present our newest member of our Sluice Box family!
The A52S Super Sluice Box is our new baby and we couldn’t be prouder! Learn what all the buzz is about by watching our video then get yours before there is a waiting list!
WHAT’S HAPPENING…
DW312VMax Matenice: Lowest cost of any machine out there to operate and keep running.
DW312Max – Maintenance & Durability
The DW312Max is a very robust machine, built with the strongest and lightest components we could develop. It’s designed to last for many years and should withstand serious real-world field use.
Major Components & Expected Life
Drive Motor
The drive motor is a high-torque, low-speed unit originally designed for small carts, bikes, or similar devices that require durability and reliability.
Very rugged and long-lasting
Replacement cost: under $100
Easy and inexpensive to replace if ever needed
Swing Arm Assembly
The swing arm is CNC-machined aluminum and fully welded.
Extremely strong
We do not anticipate any issues unless a bolt works loose
Keep hardware tight and clean
Aluminum Rod Ends
These are lightweight aluminum rod ends with high-quality internal bearings.
Much lighter than steel versions
About 4× more expensive than standard steel rod ends
Worth it for the weight savings and longevity
Bellows System
Main bellows should last multiple seasons of heavy use
Replacement cost: ~$75
Dual bellows flappers are simple 1/8" Viton rubber and should last decades
Cloth
Expected life: several years
Replacement cost: under $25
Wear Items & Spares to Consider
Rubber Bumpers
These are my main long-term concern.
We’ve run the same set for 6 trips with no issues
I recommend keeping one spare bumper on hand just in case
Teflon Bushings (Bumper System)
Should hold up very well
Minimal wear expected
Springs & Rods
Should last a very long time
Just keep all hardware tight and clean
Leg Wing Bolts
These can get lost in the field
I recommend keeping a few extras on hand
The high-quality ones we supply are the best available
Leg Pivot Pull Pins
Good insurance to keep one spare
Could get damaged if the machine gets abused, slammed around in a truck, or a rock hits one just right
Replacement cost: under $15
Structural Components
Hopper Body & Main Frame
Essentially indestructible
Will take a serious pounding
Aluminum Classifier Screen
On the lighter side to save weight
Strong enough for normal use
Just don’t pound rocks directly on it or cave it in
A small trade-off for a much lighter machine
Riffle Board
Basically bulletproof
Dead-air space design — nothing to go wrong
Dual Polyester Carpet
Creates the perfect air balance
Proven design used for over a decade
No issues to date
Minor Quirk (Not a Failure)
The only small issue I’ve noticed is that after running the dry washer all day, the leg articulating pivots can jam up slightly.
Sometimes I have to tap the base or top with a rock to get them sliding freely again
This is just dust and grit working into the pivots
It doesn’t affect performance, and it’s more of a minor annoyance than a real problem
Bottom Line
The DW312Max was designed to be:
Lightweight
Extremely durable
Easy and inexpensive to maintain
Other than a few low-cost wear items, there’s very little on this machine that should ever give you trouble.
Hello. Well, I have the 190 dry washer. Is this still considered to be a good dry washing machine? I never see anybody with this type. I was just curious.
Battery Options for the DW312Max
I personally run my DW312Max on a 15-amp lithium battery, and at only 4 pounds, it’s absolutely amazing. My buddy John Loe has done some serious backpacking trips with the DW3 and found some great gold using this setup.
At first, the difference between a 4-pound battery and an 11-pound battery may not sound like much over the first mile — but after that, every ounce matters.
Why Lithium Batteries Are the Way to Go
The biggest expense in a portable setup is usually a good lithium-ion battery, but they are worth every penny.
Compared to lead-acid batteries, lithium batteries are:
Less than 25% of the weight
Up to 10× longer-lasting
Maintain a steady voltage until fully discharged
Example:
A 35 amp-hour lead-acid battery running a 1-amp load will only run about 8 hours before voltage drops too low (around 10–11 volts).
A 35 amp-hour lithium battery will run for about 28 hours at a steady 12.7 volts, then shut off.
And the weight difference is huge:
35Ah lead-acid: ~25 lbs
35Ah lithium: ~8 lbs
Batteries I Personally Use
I currently use three different lithium batteries for prospecting:
1) Dakota 15Ah Lithium Battery
Weight: 4 lbs
Price: ~$75
Use: DW3 / DW312Max
Draw: ~1 amp
Runtime: 8–10 hours
2) 50Ah Lithium Battery (Amazon)
Weight: 11 lbs
Price: ~$50
Use: Mini-Max
Draw: ~7.1 amps
Runtime: 6–8 hours
3) Dakota 135Ah Lithium Battery
Weight: 25 lbs
Price: (varies)
Use: KT10 Trommel
Draw: ~17 amps (7.1 + 3)
Runtime: ~8 hours
Bottom Line
If you want a lightweight, backpack-friendly setup for the DW312Max, a 15Ah lithium battery is the sweet spot.
If you need longer runtime or are powering larger machines, stepping up to a 50Ah or 135Ah lithium battery makes a lot of sense.
Lithium batteries cost more upfront — but the weight savings, longer runtime, and consistent voltage make them a total game-changer in the field.
Smarter not harder is what I've always said!!! More muscle for MOVIN' DIRT!! 😉
This video shows the machine runing the tailing though a few times, drying our the material to improve the fine gold recovery.
We’ve been out testing this machine over and over again. When running truly dry material, the recovery has been amazing—consistently in the 90%+ range. Damp material is much tougher and recovery can drop as low as 60% to 75%. That said, you can significantly improve recovery in damp material by running it through multiple times. Each pass fluffs the material up and helps it dry out, and the recovery percentage climbs with every run.
What really surprised us is how well this model performed in damp conditions compared to what we expected. A big part of that comes from the extra vibration built into the hopper bumper system. On top of that, the super-fast, bumping classification hopper breaks everything up much quicker, which speeds up drying and improves overall recovery.
Routine and ease maintenance? Extra parts to have? Traveling recommendations ? Cost of unit ?
Sammy Garcia
Read my last 2 post based on your questions $1399
Ivan read the last 2 posts. I talked extensively about batteries and maintenance. Price is $1399.00
Could never listen to that nonsense all day long
Can’t wait to get My new Puffer.
Do not Piss pat off. A few more pics from the outing
Hulking out 🤪
Duly noted. Don't mess with Pat.
You feeling alright Pat? Yer looking a little green!!
Looks like a great time. Wish I had a drywasher. LOL
Still had the trailer on, Hahaha !
Introducing the New DW312Max Dry Washer
We are proud to announce our newest dry washer, the DW312Max. The price is $1,399.00, and we are taking orders now. Current lead time is approximately one month. We already have many orders in the queue, and those customers will be receiving theirs sooner.
The DW312Max is not the cheapest dry washer on the market—and it was never meant to be. What sets it apart is the fine-tuning, build quality, and material choice.
We use:
Aluminum rods instead of steel rods
Machined aluminum swing arms
Premium aluminum rod ends that cost up to five times more than standard hardware
Every material was chosen to reduce weight, increase precision, and improve long-term durability. Nothing about this machine is off-the-shelf or cheaply built.
We didn’t just build another dry washer.
We built the best using the best materials—and the result is a machine that is flat-out amazing in every aspect.
Casey Foltz
One of the many things I love about the DW312Max is how quiet it is. You can actually hear other blowers—both electric and gas-powered—running in the background, while ours just hums along.
We ran it on a 4-pound, 15-amp lithium-ion battery for a day and a half, and it worked perfectly. I used to run 60-pound lead-acid batteries, but switching to lithium made a huge difference.
This setup is ideal for backpacking the machine in. With the battery installed, the total weight is only 34 pounds.
Wow.
I'm ready to stock some of that U.S made gear...
Can you make these to interchange with the 151 ?
I was really impressed with whole setup. Super quiet too! Great meeting you two up there this weekend.
O.C.49ers club outing so much fun
It was really nice talking to you at the camp fire that night. Hope to see u again soon at another outting.
Each member, an OG.
Great club, used to be a member years ago. Looks like the Puppy feet claim.
That looks awesome! Any clubs like this up here near Auburn, CA? I’m usually out there by myself.
Patrick and I had a great weekend up at the O.C. 49ers Club outing. We had an absolute blast — great people, lots of fun, and everyone helping each other out. Good food, fun raffles… hard to beat. It’s a great club and we can’t wait to go out with them again.
The best part was that the new DW312Max worked amazingly well — honestly, beyond our expectations. Not only did the hopper classify material faster than any other drywasher we’ve used, but the recovery was outstanding. It even performed great in damp material thanks to all the additional vibration built into the bumper system.
Patrick and I were absolutely blown away by how perfectly it worked, even in adverse conditions.
This is something I’ve been wanting to buy, what is the expected loss ?
I like that im not seeing all rhe dust that you normally have white the old leaf blower style. Huge improvement imo
When is it going into production, Mark?
Great job on the new puffer pat and mark looks great
Casey Foltz
Do you have a kit to upgrade my keene puffer
We’ve been out testing this machine over and over again. When running truly dry material, the recovery has been amazing—consistently in the 90%+ range. Damp material is much tougher and recovery can drop as low as 60% to 75%. That said, you can significantly improve recovery in damp material by running it through multiple times. Each pass fluffs the material up and helps it dry out, and the recovery percentage climbs with every run. What really surprised us is how well this model performed in damp conditions compared to what we expected. A big part of that comes from the extra vibration built into the hopper bumper system. On top of that, the super-fast, bumping classification hopper breaks everything up much quicker, which speeds up drying and improves overall recovery.
I guess that's okay for primary screening, but the rate and amplitude is a bit excessive. Perhaps a third screen running at a faster frequency and lower amplitude to do fine screening would help.
WHAT’S HOT!
New and Improved Super Concentrator with an even better price!
We’ve made it next to impossible for you not to add this little power house to your prospecting arsenal at only $425.00!
We are extremely excited to present the next generation of a dredge designed for the recovery of super fine gold
This Super Mini Max Power Sluice Concentrator unit is the most versatile package that we have ever offered.
NOW OPEN TO THE PUBLIC!
