Welcome to my project site.

My name is Davetech... well, not really, but that will have to do.

This site was begun on October 14, 2007.

I plan to update it regularly, since I have several on-going projects which I think may be of interest to others.

Please note that I do not want for an instant to pretend to be an expert at home metal casting or any of the other projects I may post here. This is the first time I have attempted to build these contraptions and I am sure there are better ways of doing it. I am just showing the way -I- did it, using what little cash I have available and what ever I find in my junkpile.


Project #1 - A mini electric kiln -

(To test a refractory mixture to build my backyard foundry with)


Project # 2 - My backyard Foundry -

( up and running ) - - -


( up and running ) - - -

with Performance Observations -

March 25, 2009 - I've been threatening to build a solar powered preheater for my tankless water heater for some time now. The weather is better now and I've finally started building.

What I've gotten done: Moved my old 40 gallon gas fired water heater off the back porch back to it's original position and plumbed it into the feed line to the tankless heater. It will be used as a holding tank for the preheated water. Built a solar "hot box" plumbed with 1/2" cpvc tubing, painted black and glazed. Measured temp in it at 160 degrees F on a mild sunny day. The cpvc is rated to 180 degrees so I hope it will hold up. Dug a ditch from the house out to where I plan to mount the "hot box" collector. The ditch will have the supply and return line deep enough that it won't freeze in winter. Trying to locate a low wattage, inexpensive pump that can withstand supply level water pressure to circulate the water from the collector to the holding tank. (Would love to have a small sterling engine capable of doing the pumping, but building one of them may be beyond my capabilities.)

Changed my mind about where to put the collector and used the ditch to plant flowers instead. Forget the pump too! Thermal convection is cheaper and simpler. See the article below.


April 12, 2009 - I finally have some results to show you! Check it out!

Project # 4 - Solar Preheater for Tankless Water Heater-

( up and running, but being improved ) - - -

with Performance Observations -


March 29, 2009 - bah! The weather has been rain, rain, and more rain... so since I couldn't work on the preheater, I added a page on how I supplied my little Scandinavian wood stove/heater with fresh outside air.

( up and running ) - - -



Project # 6 - Tabletop CNC Router -

  ( Updated November 2011 ) - - -


Project # 7 - Waste Oil Furnace -

  ( Still under consideration ) - - -


  Works great! ---




Shop Visitor -

Last night (Oct 15,2007), I was cutting a 16" hole in a piece of 1/2" plywood with a hand held jigsaw, making quite a racket, and this big, beautiful black snake just slithered right in through the window, right beside me, apparently oblivious to my presence.

I have no snake phobia and just smiled when I saw his head and first few inches out of the corner of my eye. But he just kept coming and coming... "Dayam! He's long... and he's big!" So I grabbed my camera and started shooting.

He totally ignored me except when I held the camera for this shot about 4 feet from him. Then he just froze until I moved away again. Then he continued on, hunting I guess, as if nothing had happened.

It looks like he has recently eaten (see the bulge?) so he might have been looking for a warmer place for a snooze. But he checked out all the rafters overhead ("psssttt... the mice live in that big cardboard box over there with the shredded newspaper!") and then he left the way he came in.

Never did get a good look at all of him stretched out, but he was at least 7 feet long! (notice that the tip of his tail is all the way over at the right side of the picture).

I'm not sure but I think he is called a Black Rat Snake.

May 10, 2009

He's back! I walked into my shop this morning with a cup of coffee in my hand, flipped on the light to my right and started heading for the work bench and nearly ran into this snakeskin hanging from a rafter.

I spilled my coffee.

If he wasn't 7 feet long before, he is now! This skin measures almost exactly 7 feet


(No, that's not me. That's my house mate. She's prettier than me!)



Day-to-day progress on on my Heliostat project and on my CNC project can be seen on the CerebralMeltdown Forum @:



You can also e-mail me @


 Most interesting: http://www.overunity.com/index.php?topic=518.0

"Linnard´s hydrogen on demand system without electricity"

That's right, this device produces a fair amount of HHO without any external source of electrical power. It produces its own current to keep the reaction going. This is not pie-in-the-sky, hit-and-miss theory. It works. The chemicals and electrodes replenish themselves during various stages of the reaction and just water is consumed. The zinc electrode does not replate itself 100% though and ResinRat2 has been working diligently to find a way to make it do so.

When I can afford the chemicals, I plan to build this device myself, only much larger. Zinc is cheap.

<-- This thread is a good read, but pack a lunch!



Many Thanks for your hard work and determination, ResinRat2

My hat is off to you!



updated November 25, 2011


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