DIY 3 tray dry blower

[Custard]

Afternoon all
Planning on building a 3 tray dry blower useing Keene 150 trays.
Are going to fab vibrating screen that will feed hopper that will feed 3 riffle trays before being discharged by conveyor.
Been doing a bit of research but was wondering if anyone had any handy tips/advice/drawings the are willing to share before i embark on this mission?

 

[Nightjar]

Built this bellows type dryblower many years ago. It didn't miss a spec.
Put it to the test with a continuous air dryblower and it won every time, collecting the fine gold left in continuous air tailings.

 

[Custard]

Good looking unit. In your opinion is a puffer better?

 

[Moneybox]

Good looking unit. In your opinion is a puffer better?

I think you'll find a Puffer is just another name for a bellows type dryblower. I'm no expert because I've only ever built one dryblower but it does work well. The only suggestion I can make is to have as many items as you can adjustable. Adjustable air flow, adjustable bellows speed and stroke, adjstable tray angle etc. You may have to change pulleys or sprockets but at lease make sure you have to ability to do that.

Dryblowing for gold is not an exact science, there are too many variables. Soil moisture content is forever changing. Some soil types feed well, others will need vibration or steeper feed angles. Clay will behave differently to alluvial sands and everyting in between. Hopefully you are doing it for fun rather than financial reward

 

[Custard]

I think you'll find a Puffer is just another name for a bellows type dryblower. I'm no expert because I've only ever built one dryblower but it does work well. The only suggestion I can make is to have as many items as you can adjustable. Adjustable air flow, adjustable bellows speed and stroke, adjstable tray angle etc. You may have to change pulleys or sprockets but at lease make sure you have to ability to do that.

Dryblowing for gold is not an exact science, there are too many variables. Soil moisture content is forever changing. Some soil types feed well, others will need vibration or steeper feed angles. Clay will behave differently to alluvial sands and everyting in between. Hopefully you are doing it for fun rather than financial reward

Thanks Money box

 

[Nightjar]

With the bellows, found 21° was the most efficient angle for tray.
Another worthy hint; Buy a small two way bubble spirit level and fix it to frame on level surface at home. Much easier to set up machine to maintain 21° angle when you're out on the Goldfields.

 

[Goldtalk Leonora]

I'm pretty sure what your talking about is produced commercially on a trailer.....google it and see.

 

[Custard]

I'm pretty sure what your talking about is produced commercially on a trailer.....google it and see.

That wouldn't be anywhere near as much fun Tony!

 

[Custard]

I think you'll find a Puffer is just another name for a bellows type dryblower. I'm no expert because I've only ever built one dryblower but it does work well. The only suggestion I can make is to have as many items as you can adjustable. Adjustable air flow, adjustable bellows speed and stroke, adjstable tray angle etc. You may have to change pulleys or sprockets but at lease make sure you have to ability to do that.

Dryblowing for gold is not an exact science, there are too many variables. Soil moisture content is forever changing. Some soil types feed well, others will need vibration or steeper feed angles. Clay will behave differently to alluvial sands and everyting in between. Hopefully you are doing it for fun rather than financial reward

G'day Money Box,
We are certainly in it for the fun. Was a good read your 2021 post on your dry blower

 

[Hippyty79]

I'm pretty sure what your talking about is produced commercially on a trailer.....google it and see.

I seen one on gumtree made for Aussie gold hunters with 3 keenes side by side

 

[Hippyty79]

Built this bellows type dryblower many years ago. It didn't miss a spec.
Put it to the test with a continuous air dryblower and it won every time, collecting the fine gold left in continuous air tailings.


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Nice rig Nightjar how did you load it up? Shovel or machine.
Have you read a book a book called bloody gold I think it would be up your ally.

 

[Nightjar]

Nice rig Nightjar how did you load it up? Shovel or machine.
Have you read a book a book called bloody gold I think it would be up your ally.

No machines, just an hour on hour off with shovel. Yes, have read Bloody Gold, his leases were just up the track from us.

 

[Goldtalk Leonora]

G'day Money Box,
We are certainly in it for the fun. Was a good read your 2021 post on your dry blower

You are absolutely right....and you will learn a heap. Make it stong....keep it simple....go constant air with vibe motors on each tray....long tailings conveyor....large hopper and have fun. Dryblowing can be very profitable...when/if you get it right!

 

[Custard]

With the bellows, found 21° was the most efficient angle for tray.
Another worthy hint; Buy a small two way bubble spirit level and fix it to frame on level surface at home. Much easier to set up machine to maintain 21° angle when you're out on the Goldfields.

G'day Nightjar,
Been doing alot of reading and asking questions and will start to build a 2 tray bellows dry blower when I get home late next week.
You mentioned a few times (in your posts) about riffle tray cloth, any suggestions as to what is best?

 

[Nightjar]

Custard, Prospectors Patch used to sell cloth for both the bellows and contiuous dry blowers.
If you use continuous cloth on a bellows you're continually having to clean out the riffle bix. When the bellows takes a breath it sucks material through cloth.
Only ever went dryblowing as a hobby, we found a lot of gold. Always paid for our trips and declined any mention of machinery.
Good luck which ever way you go...

 

[Moneybox]

G'day Nightjar,
Been doing alot of reading and asking questions and will start to build a 2 tray bellows dry blower when I get home late next week.
You mentioned a few times (in your posts) about riffle tray cloth, any suggestions as to what is best?

I was advised to go with a SS mesh, 125 micron from memory but it was a failure. It might have worked with constant air if there was enough airflow but it didn't work on my bellows machine. The mesh was too open and failed to keep pressure on the chamber below the riffles if some of the mesh was exposed. This meant that on startup and at the end of the batch the dirt didn't flow over the trays.

I removed the very expensive SS mesh and replaced it with calico cloth and it works perfectly. My more experienced friend who recommended the SS mesh has since changed to calico as well. It eventually wears out but on a hobby machine it'll last a very long time.

 

[Custard]

Thank you Nightjar and Moneybox. The information from your and Tony (Goldtalk Leonora) posts has been a massive help.

 

[Nightjar]

Thank you Nightjar and Moneybox. The information from your and Tony (Goldtalk Leonora) posts has been a massive help.

Custard, One very important part of dry blowing we discovered early in the hobby was to always rake the top screen overflow pile flat and run your detector over it. Many species and nuggets resulted.
More info here.

Post in thread 'Bellows Dry Blower ???? ...... anyone familiar with this build' https://www.prospectingaustralia.co...ne-familiar-with-this-build.35253/post-572313

 

[Custard]

First part of dry blower done, stickers ready to go. Now to build dry blower to stick them to

 

[Custard]

Morning all,
Made a start to my two tray bellows dry blower. Base ready and bellows rocker arms are started. And a shed full of stuff for rest of build