Thermal couples and auger recommendations?

Hello Everyone!
I would like to inquire as to who makes the best thermal couples and coupling head. It looks like a J type is what I need.

In addition, I would appreciate input on auger wood chip feeds. My engine is a 351w Ford and will be running at around 1800 rpm constantly. I’m guessing the average HP load will be around 45-60. I’m thinking of welding together 3-8" auger bits used to drill into the earth. Per “The Drizzler” Luk in Poland, he feels a square auger tube is the best way to go. Any thoughts?

We buy thermocouples from Automation Direct and also McMaster Carr. We use the K type and shield them.

For the auger we use the 6" earth augers and use a 100:1 gear box with a 3/4 hp motor driven by 48 volts. It will break stuff!! We build our auger tunnel with a tapered design. For your sensor, we simply put a flap on a hinge; when the fuel is fed in, it pushes against it as its fed into our primary hopper. For the contact sensor we use a spark plug with the ground tong cut off. When the flap pushes against it, it then complete a ground circuit to the drive relay shutting off the auger. No sensor will hold up here Ive spent countless amounts of money here. Yes indeed you can get specially made devices but you will pay big dollars for them. A 2 dollar spark plug and a hand made flap work great!!

Yeah you are going about this in the right direction, with out the auger system, this will not be a fun project.Unless you can afford to pay some one to dump buckets of fuel into the machine. The auger system also adds linearity to your system, and you can control fuel height, thus controlling the drying stage. We have our own heat reclaim we have added here and is focused to this area only.


Most folks are using K type, they’re pretty close to the same scale and much more common. I really like my Omega T/Cs, they’re about $40 each but will last a long time.

Neat tip about the spark plug Matt, I’ll have to remember that.


Thanks Matt. Good info. here. The spark plug trick is pretty neat.

Do you taper at the top or the bottom? Do you use an air lock or door in your process. I like how compact your V8 version is and its rumble, rumble, rumble… I watch your videos to stay motivated!

My goal is to remove as much physical labor and time as possible from the process? I am also looking at fire suppression, given large quantities of wood.

The possibilities are endless with this stuff!

Hi Chris,
Yep, you are correct. I need the K version. Seems like a good thermocouple is a must, considering the consequences if on failed in the high heat areas. Where did you purchase yours?

Oh, I bought a headset so I can actually participate in the Friday night discussions lol I had some technical issues last night.

Curious about the motor. Do you have 48 volts on tap? How many rpms is it? This is an area that is totally new to me. I am assuming it’s a DC motor and you turning it on and off. Do you regulate the speed too?

We taper it in “V” shape, it is designed so the auger stays put and sits in the wedge and also touches the bottom. We also use feed flaps that ride on the auger to keep the fuel from bridging in here and also to feed a consistent amount without overloading the auger.

Here is the beauty of the auger system. You dont need an airlock on it!! If the fuel is low in the auger hopper only and not in your primary hopper, there should be enough fuel in there to slow that air blast down when you open the lid to the big hopper. In addition if you have the arduino controller, it will automatically compensate for these events. Even on our little machines with the Arduino this is really is no longer an issue to an extent. When we fill the little guys we do it in smaller fills. Open the lid dump fuel in close the lid and repeat until full. Usually three scopes with our scooper we have.

We use a step up module that supplies power to an automotive long duty cycle starter solenoid. The relay in our box supplies power to the step up module. I should rephrase how we have this wired with the spark plug. When the ground i complete it turn the relay on. So we have the power supply out on the relay connected in the “Normally Closed” terminal.

Yes we use a DC motor no speed regulation, these are 90v rated. If I could find a step up that big Id use it!

Also thing big like 20 cf or larger!!

Thanks Matt!

Interesting. Are you heating the air around the auger like a GEK?

Here kind of what I am thinking: Perry of Oakley Biomass handling woodchip bio intake auger screw - YouTube
I can fire up my Mahindra and dump wood chips in a trough. This is interesting with the turntable: - YouTube

SSI's "Monster" Shredder - (WIDESCREEN VERSION) - YouTube Small version of this for chunking ? : )
The Chunky Monkey!

Do you have any video of your auger system showing the spark plug?

Yeah Ive been looking at those shredders, You could build a hopper that could hold full logs and have a feed system to feed them into it. This could be placed directly on top of the gasifier.

No APL has patented this system, patent or no patent we wouldn’t go about it the same way anyways. However, we will are in process to patent our systems. Its been a long haul and a lot of work to get to this point so we now need to protect ourselves.So cant really give to much specifics on it.

No I have not done a video on the newer style auger yet.

Interesting. I thought APL kept everything open source. Times have changed. I think this demonstrates a new premise for them. They get a lot of grant money.

There is a mini chunker like that, that is open source. Food for thought: Shredding LCDs, CPU, IC, Chips, Capacitors and lot more electronic components - YouTube

Nope no grant money that is long gone.

I saw the approval for 2 million in grants. Trying to find the document again. There is mention of it in the Dinwoodie addition the board of directors as well. Dinwoodie is a private investor as well. This is all recent.


Ah, I knew I saw the $2 million somewhere. Thanks!

Must be nice, we have yet to receive any outside funding.

Hey Matt,
Have you connected with GVSU / Michigan Alternative & Renewable Energy Center?

Yes, They are trying to help.

Grants are plus / minus anyway. It takes a LOT of time to write for them and you don’t always get the award. Grant writing is a science too, also known as a royal PITA.

Try to become an adjunct professor at GVSU. Offer to teach a couple of sessions, etc. This would likely lead to bigger things.

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