January 26

About This Site…

Celtic Cross Engineering is more than just an “Engineering Blog” Much more! It is my ultimate Mad Scientist Blog, Lab Notebook, and Instructions for others of the same bent.  Those who wonder about this world and this life we live, who want to know the deep questions: Why am I here? What Great Mysteries are out there to explore? Or how about questions like these:

  • Is the speed of light really a constant? What if it is not?
  • Can you transmute elements without the use of a cyclotron?
  • How can I make a good smoked cheese without paying a fortune?
  • Is it possible to extract free energy from the vacuum?
  • Do fossils prove evolution, or disprove it?
  • Does a raised bed garden produce more food than a traditional in the ground variety?
  • Can radio waves travel through the ground?
  • What about abandoned technologies? (ie: things that were superseded by new technologies, but perhaps were not investigated to see how far they could be developed?

Things like that…

So, below are the basic categories of the various posts.  These are not pure blog posts – the dates basically reflect the day the post wast started but I will continue to update/add-to/change posts as I work on those ideas or experiments.

Let’s Explore!

Basic Categories Within Celtic Cross Engineering…

Category: Uncategorized
March 20

Building a precision “Scroll Saw” or Jigsaw…

Back in my day (think 70′s and 80′s) we used to call table “scroll saws” jigsaws.  We called hand held “Jigsaws” Sabre Saws.  Well, I guess some all powerful authority decided that the names must be “switched all around” and now “Scroll saws” are the table variety and Jigsaws are the hand variety, and, well…


Scroll saws are a very nice tool to have in any Mad Scientist laboratory because of all the various things you can do with them outside of creating “scroll-work”… for example if you create printed circuit boards that are not square, but follow some weird shape due to the enclosure, or if you are making lost foam metal molds, or a variety of intricate cuts…. you need a precision scroll saw. sure you could get yourself a CNC water jet or some plasma cutter device and pay thousands, or… a scroll saw does the job much cheaper.

Problem is that a precision scroll saw is expensive.  Let me explain.

There are essentially 5 types of scroll saws out there. The spring tension saw, the parallel arm saw, the C-arm saw, hybrid parallel saw, and the oscillating saw. All of these saws have their pros and cons, and their basic configurations are shown here. If you look carefully you will see that each has issues with the saw blade that effect the precision of the cut.

constant tension

spring tension scroll saw












The spring tension scroll saw is a common one from the 50′s and 60′s but is not seen that much today even though the basic configuration is quite simple.  While the blade stays in the same place during the entire period of motion, the problem is that the tension on the blade changes – being at it’s highest when in the down position, and lowest in the up position.  This means that when the workpiece is pressed against the blade, the tension is in a constant state of weak, then strong.  This means that the blade flexes, and the cut will not be as precise as it could be.  It also means that the blade weakens and breaks much earlier than it normally would if it were under a constant tension.  The overall precision of the cut is compromised.

c arm

C-Arm Scroll Saw…










The C-Arm scroll saw as shown in the above picture has the advantage of keeping the blade tension constant, however as can be seen from the motion that is made, the blade position changes with respect tot eh cutting table and work-piece.  While very thin pieces may not be effected as long as the table cutting position stays constant as in the picture, thicker pieces will have issues with precise accurate cuts.  This becomes even more problematic if angles cuts are being used.  This is because the blade cantors back with the C-Arm as it goes through it’s periodic motion.

paralel arm

Parallel Swing Arm Scroll Saw










The parallel swing arm scroll saw is an improvement on the C-Arm, and also represents the oldest of the powered scroll saws in existence. Originally foot-peddle powered, these older saws had very deep throats upwards was three feet, making the offset that occurs when the saw moves upward or downward from center very minimal.  But as you can see in the picture above, this offset becomes much more noticeable as the arms become shorter as in modern day scroll saws.  Still, this is the mechanics of most inexpensive (under 200 dollars) scroll saws you can buy today.  Again, precision is lost because of the offset.

2 parllel

hybrid parallel arm scroll saw








A variation on the parallel arm scroll saw is the hybrid shown here which uses “rockers” to move a cam like series of mechanisms that moves the bald up and down, but again, because the final rockers that attach to the blade are set on a pivot, the blade will have some front to back loss of precision as it rotates around the center of the rocker pivot. more expensive scroll saws employ this method of blade drive to greatly reduce vibration of the saw, however the precision is still an issue because of the aforementioned rocker rotation.

So in all these cases, we have the design of the saw effecting either the tension of the blade during it’s travel, or the actual position of the blade! What we want is for the blade to stay put and only move up and down – nothing else!

There really is only one way to reliably move a blade up and down under a constant tension, without any loss of precision and that is shown below : The oscillating band driven scroll saw.  These types of saws are the most expensive, but are also the most precise scroll saws that money can buy.


The oscillating band scroll saw – most precise money can buy.










Here is the deal: I needed a scroll saw.  I wanted one that was precise.  I’m a cheapskate. I like a challenge.

I decided to build my own.

I decided to build a precision oscillating scroll saw using a hybrid design that combines the band of the standard oscillating saw as shown above, and the “main rocker” idea of the hybrid swing arm saw.  Below is a simplified drawing of the saw I am building followed by the actual build itself.


Simplified diagram of my oscillating band style scroll saw. blade guide and other minor items not shown.













My version of the saw uses the rocker from the hybrid parallel arm saw, but then connects to the blade via a steel cable under tension as opposed to a continuous belt or band.  Using brass sliding door pulleys and a tension spring (not shown).  My current build progress is shown below.


Collection of junk to start with.













The collection of stuff I had on hand – those aluminum tubes I found in a dumpster next to house construction – by the way: House construction dumpsters are a wealth of great free stuff – but get permission first!  Usually they don’t mind because they have to pay a fee for every pound, and anything you take saves them money!


cleaning up the tubes (they had cement and oxidized tape on them)














cleaned up and cut to length.













By the way, you may have noticed behind the staks of cut tubing that I am building a mini Tesla supply – those door-knob caps are from Russia, bought them about a year after Chernobyl – I wonder where they came from?


assembling the frame














It’s coming together.














The combination of the two sets of struts makes the cantilevered arms of the saw very stiff.














Northern Tool Pillow Blocks – about 9 bucks a piece.














Pillow blocks mounted and shaft inserted.














The section for the rocker arm to be mounted to the shaft. Got to get the welder out!














Here are the brass pulleys for the saw…














Old dryer motor for power…















March 10

Hidden Gems in Old Technology…

Have you ever wondered about old tech? Let me explain.  Did you know that about the time that the transistor started taking the place of tubes (or “valves” if you are of European persuasion) that electron tube technology had progressed to the point of creating tiny tubes the same size as discrete transistors?


Now that is a tiny tube!

Eventually as transistors became more inexpensive to make, and more capable, the tube faded – but then it got re-invigorate as audiophiles (and Heavy Metal Guitarists) realized that transistors just could not reproduce the warm sounds of the tube in their amplifiers. Hence even today the best and most expensive amplifiers employ tubes.

There have been many technologies like this that have been all but forgotten, left to rot on the ash-heap of history.

But have you ever considered that those technologies may not have given us all they had to give? Is it possible there are anomalies and other design considerations of an old technology that were never considered at the time, and now lie waiting like some missed vein of gold in an abandoned gold mine?

Well… There are those who would try to steer you clear of any such notions – and based on what exactly you are looking into, there may even be those who would attempt to force you to stop looking into these things.

That makes me want to look all the more… and while we are on the topic of electron tubes (or valves) let us go to one of the fathers of the electron tube Philo Taylor Farnsworth. This man developed an amazing array of devices including the very first completely electronic Television and Camera. The funny thing is, most people have never heard of him. Much like Nikola Tesla, while almost single-handed developed an entire new technological arena, he got barely any credit for his inventions.


PT Farnsworth with his fusor in what looks like a cookie jar…

But one of his most interesting, and mysteriously, his most under-appreciated invention was the Farnsworth–Hirsch fusor, employing inertial electrostatic confinement. In other words along with television, this man created the first sustainable fusion reaction in a device that many high-school science fair participants have recreated!


High School Science Fair. Not sure how old that high school student is… Then again, maybe Neutrons increase beard growth?



I may at some point try my hand at a Fusor – but even the basic ones need a pretty good vacuum – even my little vacuum pump is nowhere near what is required for one of these! Still, a fusion reaction in my workshop… now that would be something, but I digress.

The point of this post is to think about technologies that are “repressed” not necessarily by big government or big corporations (although I am sure that occurs) but by “history” and neglect.

As I think of new ones I will add to this post. For now, check out this interesting link on the Farnsworth Fusor. (note, the document appears to have been scanned and contains many spelling and format errors, but it is worth the read!)

February 10

Culvert Pipe Food Dryer…

So I got me some leftover plastic Culvert pipe.


Plastic Culvert pipe has many uses…other than being for culverts.

What to do with this I thought to myself? Then it came to me… Make a food dehydrator out of it! So this is what I came up with…


Finished Food Dryer with old blower from a Christmas “Blow up Snowman”

So using a old blower fan I had from a worn out Christmas “Blow up Snowman” some plywood, some plastic window screen, and a couple of “Banned” 100 watt light-bulbs, I proceeded to build this little contraption.


Those are real 100 watt “Edison Bulbs” – Contraband these days in the USA…

Using two ceramic light bulb sockets and 2 100 watt light bulbs I first created the lower section that generates the heat for drying. Note that there are concentric ring of holes around the bottom of the pipe and where the plywood meet so that air is constantly moving, carrying heat upwards.


single sections of pipe-rings with window screen held in by zip ties.

The pipe is cut into “Rings” that are done ins a way so that can stack like plates on top of each other. Then using plastic window screen and plastic zip ties, you create the food holding trays. As these are all high heat plastic (they withstand up to 400 degrees) they are dishwasher safe!


Hot water heater thermostat turns off the bulbs if things get too hot inside.

The blower goes on the top to suction the air out of the dryer and keep a constant flow of air moving. The metal dissipation plate forces the air to move around the food completely so there are not spots where air is trapped. The hot water heater thermostat is there as a safety precaution to shut off the light bulbs if it gets too hot inside.

I have dried tomatoes, bananas, many spices, etc in this dryer and it works very well. I would probably make the stack-able rings a bit more stable if I were to do it again, but all in all this is a single day project that can really add to your food processing skills and give you a bountiful harvest of dried seasonings, “sun dried” tomatoes, and other dehydrated delicacies!


February 7

A Cold Smoker for Meat and Cheese…

I like a good smoked cheese… Problem is, when you buy it at the store, it is very expensive.  Then you find out (if you care to look) it’s not really smoked at all! (at least not most of them).  No, instead most so-called “smoked cheese” you get at the store has been “Flavored” with liquid smoke, and then it’s been brined in a “colorant” that makes the outside brownish to give it that “Fresh from the smoker” look.

Pish -Tosh to all that! I want real smoked cheese!


This can smoke your ribs… but not your cheese!

What to do?  Well you cant smoke cheese in a traditional hot smoker, such as a bullet smoker:

Not unless you like a burned, melted mass of glop.  I don’t prefer that…

No, Cheese must be smoked in what is known as a “Cold Smoker”.  I decided I wanted to smoke cheese and a variety of other things so it was time to build one of my own. So I decided to build mine as a 2 by 2 by 4 foot box out of scrap plywood as seen here.




The Back of my smoker sticking out of my workshop on a cold day.

Here are several more pictures of the smoker…


Front of Smoker






Inside shot of the smoker showing racks and the smoke distributor on the floor.






This shows the smoker with the racks and the distributor removed. Note the creosote collector – some spilled out when I was moving the smoker.













The smoker has a “smoke distributor” on the bottom – which is basically a false floor with large holes cut out to allow the smoke to permeate the entire box.

The smoke pipe runs down the entire length of the smoker so that the smoke cools, and so that creosote (which makes food bitter) is condensed and collected in a little tuna can at the bottom.  This has to be cleaned out after every smoking session.

The racks are 1.5 inch dowels that sit in cutouts on the side of the smoker.  The food to be smoked can be laid directly on the dowels, or (in the case of cheese and smaller items) placed on dollar store cookie cooling racks that then sit on the dowels quite nicely.

The door seals shut by using 2 lengths of cotton clothesline.  The clothesline seals against the door when it is shut for more or less an airtight seal.


The Smoker loaded up with some chicken and a small turkey.

When loading up the smoker with meat, I always keep a drip pan underneath to try to keep as much of the raw meat drippings getting in the wood.  You cant stop it all. so you wipe down the inside with Clorox between smoking sessions (not needed when doing things like cheese or when smoking salt).

Now for the most important part of the smoker – the smoke generator!

The smoke generator is the box that sits atop my smokier, raised up in the air.


The smoke generator.









I could have gone the rout of using a commercial smoke generator such as the “Smoke Daddy” Cold Smoke Generator but that would not be in keeping with my nature of “Build your own” – besides, the smoke daddy compels you to use their special “smoking wood sawdust chips”.  I wanted to use any kind of wood I can purchase from local sources, or cut from trees such as apple orchards, etc.

So, I built my own from an old Army Equipment box.  The way a smoke generator works is by using a negative pressure venturi inside an enclosed container which is where the smoking chips are burned without oxygen. The box is an hardened aluminum box with snap-down lid. The iron pipe goes through the center of the box, and where it passes through the box there is a hole. The arraignment looks like the schematic shown here.

<<Schematic Diagram Coming Soon!>>

The venturi pulls the smoke and keeps just enough air flowing into the box to keep the coals going once they are started from the two “touch-holes” on the outside of the box.


Smoke Meat and Beer… Mmmmm!


The smoke then proceeds down the long iron pipe into the smoking box, where it emits from the base as cooled smoke.

Shown here, I am using Cherry Wood Chips purchased at my local “Harris Teeter” Grocery. The large beer next to the smoking chips is a delicious brown ale my brother Jamie made and bottled himself – nothing goes better with smoke and meat than a good, ice cold brew!

I shall update with more pictures of the smoke generator as I get time…


January 26

Converting an inexpensive AC Welder to DC Service…

About 9 years ago I converted my standard Lincoln AC “Buzz Box” Welder into DC Service. I did this by building a massive full wave bridge rectifier. It has provided great service and welds very nice – DC welding is acutally quite a bit easier than AC welding, and in fact, this DC full wave Bridge is clean enough for Tig welding should I ever get the bug to do that.

Here is how I did it. (Excepted from my old original website hosted on Comcast – and it is still there even though I haven’t been a customer in over 9 years!)

Welding can be done with AC but for better welds and for work on thinner sheets of metal, DC is needed. Lincoln sells a inexpensive AC arc welder that can handle as much as 225 amps of current at about a dollar per amp. A DC welder of this current can cost twice as much, and a Mig welder of this current is way more. I decided to buy the cheap Buzz Box and then convert it to do what I want. First I built this DC arc conversion. Next I will build a Mig and Tig extension and then I will have a fairly complete welding system for very little money.

The basic parts – check out those massive diodes!

I acquired these four 300-amp,200-volt diodes from Ebay for $7.00 apiece. They originally sold for $90.00 each. You can get this stuff cheap and there. The old transformer will be used as the choke coil (see circuit diagram).

Close up of the diode, these suckers are Huge! The measure in at 3 inches across.

The heat sinks for the diodes and the cooling fans in the back ground.

The heat sinks are prepared.

Using copper strapping to make the connections have as low resistance as possible for the massive welding current.

The terminals and heat-sinks must be connected such that the heavy current (as much as 225 amps) can flow unrestricted, and so that cooling is possible in both air or in a oil bath, and so that the whole is structurally sound. To insure all of this I used both aluminum and copper strapping scavenged from the transformer shown earlier. Notice how the aluminum is wrapped with the copper.

Below is a diagram of the full wave bridge. Again, while the circuitry is simple, the actual physical construction is challenging due to the heat dissipation requirements and the current carrying requirements.

Schematic Layout

Completed Rectifier in the welding cart.

A view of the completed air cooled full wave bridge mounted on its nylon header. The header is made from a nylon kitchen cutting board. The box is an old main-frame computer power supply box.


The finished DC rectifier showing connection end


Rectifier showing Choke and cooling fans


This welder has given me 9 years of great service – never overheated, and I have never had any issues with the rectifiers. A great way to build an awesome system and save money. Your just not going to be able to buy something of this ruggedness without spending a ton more money.


January 26

Jumper Suit, Panal Van, and a Traffic Cone…

I have long believed, and still do, that if you have the three items mentioned in this title – a workman’s jumper suit, a nondescript panel van, and a single orange traffic cone, you can get away with just about anything.

Take over_the_world_1

With these 3 things I can take over the world – and so can you!

Think about it. The official government seal of the “Department of Redundancy Department” the jump suit, the hardhat, the traffic cone, why you could help yourself to just about any of a cities infrastructure without anyone taking notice. When was the last time you paid any attention to someone working on traffic lights or putting up spy cameras, or NSA cellphone snooping devices?

Think I’m kidding about those snooper devices? Check this out – in Seattle, they have peppered the city with little boxes like this which are part of the “Aruba Mesh Network” which allows them to collect all of your non-encrypted phone calls and texts… (well, it collects your encrypted ones too, but if you did your homework, they wont be able to see/hear those…).

Aruba Mesh Network node.

So lets say you are a curious individual who wants to know what your government is up to these days… You get the aforementioned Van, jumpsuit and hard-hat, and don’t forget the traffic cone! You may want to throw in a clipboard for good measure.  Then you go visit one of these nodes.  Take it apart and see how it works. Load it with some new software that keeps tabs on those who are keeping tabs on you. Be advised, that you are treading on dangerous waters here – you don’t want to end up like Edward Snowden unless you know what you are getting into…

Think about the implications…

January 25

My Vacuum Pump

All good labs should have a vacuum pump.


You need to make all those glow tubes so your lab can look like the lair of a true mad-scientist!  And in my case, I need to build a good triggered spark gap, and I want to be able to use a vacuum to control the spark duration and length within.

I need… more… Vacuum!

So I got this old vacuum pump that was originally for a neon sign shop, and then later was used by a refrigerator guy to pump out the freon from old systems, then given to a guy I knew who gave it to me. It was in sad shape, so this page is devoted to it’s rebuild.

So here is the pump so far…

Basic Vacuum Pump

Note that the mason jar is used for filtering moisture or other contaminants from the air pulled out so as not to have that enter the pump housing and possibly cause corrosion. I sanded and repainted the motor and pump housing hunter green… because that is what color paint I had on hand. The switch is from my junk box, as is the mounting hardware (old curtain rod holders).  The wood is plywood flooring salvaged from house construction in the area.

Update 01/26/2014 : I finished cleaning and fixing the connectors and have built out the system.  Need some good non-collapsible hose line and a better way to secure the moisture filter. Note that the switch plate is off as I am painting it hammered bronze to give the pump a “steam-punk” look.

Updated Pump with filter and connectors.

Close up of moisture trap

I will update this as I get it to completion to be used in my all new DC Pulse Tesla Spark Gap.


UPDATE! 02/02/2014 – Vacuum Pump Completed.

The Finished Vacuum Pump

Looking Very Steampunk. I may decide to add a brass plate or something to make it look more “Old-School” Victorian Lab, but I am very happy with the results. It pulls 20 Hg on the scale – This should suffice for my current experiments.


January 21

John Bedini’s “Scalar Beam” Device

Okay I will be honest with you, I believe about 99% of the free energy advocates are either ignorant of basic electrical principles, charlatans, or are just plain nut-jobs. In fact even the Guru of Weird Science, Bill Beaty agrees – read his excellent post about Free Energy and the promoters of such here.

But John Bedini is a bit different.

He actually owns a company that back in the 80′s and 90′s the made some of the best audio amplifiers in the business.  These were the kind that had in recording studios. He designed and built them.  He is a real electrical engineer.  It is called Bedini Electronics and here is pic of just one of his awesome amplifiers.

That, my friend, is a very nicely made amplifier!

So when he claims that he has found ways of producing “Scaler Fields” and “Longitudinal Waves”, any good scientist and experimenter should not just brush him off.  This guy has some serious street cred going!

I plan on looking real hard a some of the stuff that has been attributed to Mr. Bedini as well as stuff he has actually said/did/designed/built in this burgeoning field of free energy and “Scaler Electrodynamics”.  Both of which are considered as nonsense by the established Science and Engineering worlds.

But the exciting discoveries in this world are never found where the “Establishment” is located, but always out on the lunatic fringe.  Unfortunately, as Mr. Beaty pointed out so eloquently, this is also where the scammers, con-men, and actual crazy people hang out as well.  Tread carefully!

Today I want to look at the so-called “Bedini Scaler Beam” Device. You can see a simple ascii drawing and description here, again by Mr. Beaty.  At this point I need to perform some clarifications…

Mr. Beaty is a great experimenter, builder, and thinker in his own right, however I have to take issue with his statement:

Here’s a suggestion for “scalar” experiments from a conversation with John Bedini.
Mr. Bedini encourages everyone to try this experiment, but warns us that this device
is patent applied for, so you should only build a single unit for your own use.
- Bill Beaty, 1/21/95

Um… I’m sorry, but with all due respect, nobody is going to be able to claim that glujing two magnets together in a bucking fashion and wrapping a coil of wire around it constitutes a “patentable” device.  Nope, sorry, but that is utter BS.  Make as many of these as you want, heck, sell them on ebay – I will (If I find out they actually do anything)!

It would be like me trying to patent the garbage can… oh wait, right, Apple already tried that.

So…anyway, I have reproduced this “Scaler Beam Device” in my own lab.

Using two Neodymium Magnets I pulled from an old disk drive I created a proto-type device.  Later, if it seems worth it, I will buy some block style magnets and build a much more robust version.

Even with the relatively small magnets I had, it was very difficult to get them to stay face to face in a “bucking” fashion (north to north or south to south).  I used a couple of zip ties to keep them together and wrapped some small diameter hookup wire around them.

Instead of using “motor noise” as shown in the original diagram, I opted to use a square wave pulse train generated from an old 7404 hex inverter hooked up as shown.

7404 hex inverter oscillator.

Breadboard Layout

I used the above general oscillator circuit with a C of 22Nf and R1 and R2 of 2200 ohms.  This gave a 25% duty cycle at approx 30Khz. Here is the circuit layout on my breadboard (Note I am using a different power supply than the one on my breadboard because I wanted a higher voltage and more power to the Bedini coil).


My 1960′s era Sencore PS120 tube oscilloscope.


Bedini Coil using 2 hard-drive Neodymium magnets

Here is a closeup of my “Bedini Coil” and breadboard of the circuit. As you can see I used 2 zip ties to hold these stubborn magnets together.  I wrapped the hookup wire around the assembly, and added a 100 ohm resistor in series as the coil did not have enough resistance to give a decent load to the oscillator – it acted like a dead short.  The resistor in series added enough load to actually pulse the coil.

I may actually perform the noisy motor test as well, but I think a controllable oscillator is a better lab test of this device.

Next is the waveform seen at the coil on the oscilloscope.


Waveform on the Bedini coil – note there are voltage spikes at each transition of about 6 volts both positive and negative.

What can be seen here is that the coil exhibits a somewhat unusual waveform that has a 50% duty cycle and had transition voltage spikes.  I can understand the spike, but the change in duty cycle is strange.


Conclusions: At this point I did not notice any unusual “Scalar Field” non-sense.  No “Men in Black” came storming into my lab demanding that I stop experimentation with this stuff, and there were no changes to CDs or the taste of wine in the house as suggested by Bill Beaty.  Instead, I believe I will build a more robust version of this device with configurable frequency, and voltage levels, and of course, better measuring techniques.

What I am interested in testing is if there are indeed “longitudinal Waves” coming from this device, then they should be able to penetrate a Faraday shielded box and be detectable inside.

We shall see…

-David T. McKee


Updated on 02/10/2014


Hey kids… so I built a new “Bedini Scalar Beam Device”! So that means I must be “Breaking Copyright”… oh right, this is not a copyrightable device…

Moving on…

Here is an experimental schematic of what we are trying to build here – I got this picture from another on the web performing this experiment – he decided to put a xenon flash tube next to the magnet for whatever reason, I just want to give you a gist of what this device looks like.


The “Scalar Beamer” – or maybe a special kind of strobe light?





So here is my new Scalar Beamer – and I used both the electric motor scheme as Bill Beaty suggested as well as the DC square wave pulse oscillator I built for the initial tests.

This has 60 turns of doorbell wire wrapped around 2 ceramic rectangular magnets I got at Home Depot. I got similar waveforms as before and no immediate effects however I did note that a standard antenna coil was not picking up very much on the oscilloscope which is unusual.  I need to get some time and build a better set of enclosed detectors as well as get some magnet wire to wrap the magnets with.  There may be some strange principles with a coil like this, and it is worth another look.

Here is test coil # 2:


Bedini coil # 2…











More updates to come!