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The Mechanical Tweetie Bird

Checkout this little jewel of a flying machine. A good friend of mine, we’ll call him THM for now, is probably the best machinist I’ve ever come across in my days. He put this bird together. It was equipped with a 4 cyl piston aircraft engine originally, but rather costly to keep flying due to the yearly majors and maintenance fees. So after doing some research he decided to try using a turbine engine and reconfigure the drive train from the ground up. It was a radical idea but proved to be a good one.

The turbine engine he finally settled on was a Solar unit used on the CH-47 (Sky Hook) helicopters for power generation and the hydraulic systems. He purchased two or three of them and put one together that was air worthy. That was the easy part and he moved on to designing the drive train. The transmission had to be built from square one to achieve the right gear ratio including shafts, gears, bearings and that whole ball of wax.

THM owns a well equipped machine shop and set about using his expertise to build the transmission and related drive train components piece by piece. The original main rotor shaft was also re-fabricated from titanium stock due to some harmonics encountered with the changes to the drive train.

The skill set required to do something like that says everything you need to know about the man. He’s a machinist with the heart of an engineer and the vision to make it all fly.

The trailer (bird cage) is used to move it to air shows. If time allows I’ll get some video of it flying next spring.


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PCB Wall Mosaic Finished

Ok, it really is done this time. I added more PC MOBO’s and the boards from a huge pile of vending machine coin mech’s and bill validator’s to the little wall, then added some accent lighting for good measure.
Any additional junk electronics will be used to trim things out or put on a shelf for now.

What started out as an attempt to get rid of some junk is now art and spare parts on the wall. It was actually a lot of fun scrapping it all out and in my opinion looks like it’s right at home in the studio. Each to his own I guess.

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Freed Eisemann FE-15

The Freed Eisemann FE-15 was a battery powered TRF (Neutrodyne) AM broadcast band set manufactured in 1925. I’ve done the preliminary work on the chassis and stripped/refinished the case so far. Some of the wire wound resistors will need replaced and the tube sockets have splits in the side shells which will also need fixed. Other than that the radio is in fair condition, but for now it’s just another ornament on the shelf.


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Half Baked Studio Update

I’ve managed to find a bit of time to spend on the music/studio projects. The whole server move/WordPress upgrade and associated graphics work set things back a few measures. It was however a worthwhile project, WP Ver.3.4.2 is great, the new server ( is top of the line and the websites are on the road to recovery. I mixed in some wood processing while I was at it and things are looking good on that front.

On the studio side of things I’ve spent some time remixing some of the older stuff on the MiniDisc 4 track discs. I uploaded those to the server in WAV format rather than compressed or in MP3 format, you just lose too much of the sound in the process. Some of the material is with my vocals (not good) so it is what it is. You can click on the blinking button next to those and load the lyrics in another window. I’ll add these all to the music page along with some with only guitar added.

I Need Too

The Enemy Within

My Machine

Going Underground

Cracked Society

The next song was something that I and a couple others put together. Mike D. provided lyrics and rhythm guitar, Matt B. bass, and I furnished the synth parts and lead guitar.

Drug Land Craze

Misc. Old Tracks


Under Fire

Never Stop

Face The Storm

Losin’ You

My Daze

Atwater Kent 10C Model 4700

A few years back I had the opportunity to help with an estate liquidation/cleanup that was rather interesting. The deceased was a retired electrical engineer (Caterpillar), and having lived through the Great Depression saved every scrap of electrical/electronic gear he could get his hands on. After he passed away a big majority of the stuff had been packed/thrown into a two car garage and was a real mess. Boxes of vacuum tubes, hardware, vintage radios and the like were floor to ceiling deep. It was one of the biggest messes I’ve ever had to deal with.

Before he passed away he stressed to his son that every box of stuff should be looked through in detail and for good reason. It was a regular time capsule of electrical components and electronics. This was being done for a good friend of my brothers and we were the first ones to look through it all. When we arrived on the scene it was just one big pile of broken vacuum tubes, hardware and you name it. We also earned the right to acquire several truck loads of parts and pieces in the process. Included were quite a few very early radios and older test equipment and it took some time to go through.

One such item was what looked like a piece of wood with vacuum tubes and coils mounted on it. I had no idea what it was and tossed it to the side to gather even more cobwebs and dust. Then one day my curiosity got the best of me and I dusted off the name plate for a closer look. It was an Atwater Kent 10C Model 4700 breadboard style radio built circa 1924. The power switch and three tuning knobs were missing but it was all there other than that. The mahogany breadboard base was also in good condition so I decide to clean it up and use it as a knick knack on a shelf somewhere.

The AK 10 (4700) was the successor of the rare Atwater Kent “Radiodyne” (as the original version of this model had that name on the component ID plates). It was soon discovered that another company (Western Coil Co.) had the rights to the “Radiodyne” name and the metal ID component tags were changed to read; “model 10” in place of the Radiodyne name. It was a TRF (tuned radio frequency) set without reaction (non reg.dir.receiver). It was broadcast band only and had three tuned AM circuits. It used 4 UV-201A and 1 UV200 for tubes.

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I removed all the board components next and and then refinished the breadboard. I left the wiring on the bottom of the board intact. The transformer and choke coil in the base of the tube island tested good, as did the wire wound resistors in the circuit. I then used electrolysis to strip the metal parts and painted those parts with hammered finish Krylon. The Bakelite parts rubbed out nicely and I polished the brass and copper on the rest of the components. It was also missing the bypass capacitor along with the tuning knobs and power switch.

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Working AK 10Cs were selling for anywhere from $1200-2000 on eBay so I listed it for auction and it sold for $485 as is. I packed it up in good fashion and it shipped the next day.

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Caterpillar 3516 Engine Rebuilds

In past years my primary occupation has been as a mechanic/machinist and then process management and control in the latter years. Twelve of those years were with companies in the Texas Panhandle as an engine re-builder, natural gas fired irrigation engines. Boring bars, valve reconditioning, head mills, power hones, the whole ball of wax.

On returning to Illinois I took a job for a petroleum company (oil field) playing nanny to a 3MW power generation station. The plant utilized 4 3516 Caterpillar engines as prime movers turning 800 KW generator ends. The fuel feedstock was field gas piped in from two directions via 4″ pipe with two LeRoi gas compressors (screw type) and piston units out in the field. There were also three 398 Cat.’s and a 3412 unit out in the field.

The gensets ran on a 480v buss and it was then stepped up to 13KV for distribution to the company owned/maintained field grid. The 480v switchgear incorporated Woodward 2301A governors and synchronizers and was all simple relay logic stuff, as were the rest of the engine controls. The generator ends had digital voltage regulators but were not wired for cross current compensation.

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I did all the engine rebuilds/maintenance in house as well as the switchgear/electrical repairs. The gas compressors and all that were just extra chores. However on two occasions we did ship the engine blocks out to have the decks re-surfaced. The 3516 weighs 17,699 lbs dry, displaces 4210 cu in/69 liter, has a bore and stroke of 6.7×7.5 in, and is turbocharged with after cooling.

The 3516’s usually had to have the heads, pistons, and liners replaced at about 20,000 hrs or so. If you didn’t the valve heads would pop off and really muck up the piston and liner. Major rebuilds and main bearings at around 60,000 hrs. The units ran 24 hours a day so it didn’t take long to rack up 20,000 hrs on one. That by itself kept me busy and chasing bugs in the relay logic controls filled the rest of my time slot.

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It was fun while it lasted but I don’t miss it much. I’d much rather work on the process management and control end of things now that getting some age on me. Throwing cast iron around is getting old….

Atwater Kent Model 85 Restoration

I acquired this radio a few years back and have since started the restoration process. This is their second console superheterodyne radio. Due to RCA trying to corner the market on superhets all the other companies up until 1930 such as AK, to that date had made only TRF’S or tuned radio frequency sets. It had AVC (very rare in 1930), used Pentode output, and had image suppression.

It used the following tube line up:

  1. 235 – Mixer
  2. 227 – Oscillator
  3. 235 – IF Amplifier
  4. 224 – Plate Detector
  5. 224 – AVC and Volume Control Tube
  6. 247 – Pentode Power Output
  7. 280 – Rectifier

It was in pretty fair condition cosmetically, the grill cloth and speaker were intact and the chassis was in good condition.

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All of the transformers and chokes on the aluminum chassis tested good, and the resistors that I could check were within tolerance. The electrolytic filter cap was junk and I replaced it, but left the original metal canned caps in the circuit in place. The biggest issue was with the rubber coated wiring on the chassis that had turned to junk. All the cloth coated wire was still in good shape, but the wire feeding the IF cans, tuning cap and grid caps had to be replaced. Unfortunately the audio output transformer mounted on the speaker was open on the primary side. The primary is supposed to be 500 ohms and the voice coil side .25. A real show stopper.

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I don’t know the slightest thing about refinishing but gave that a shot also. I stripped and sanded it inside and out and used some Minwax Antique finish to rub it down with and left it at that. I also found a reproduction face plate for the tuner over at Old Radio (Mark Oppat’s site) and replaced that.

Hopefully I can find time to finish the project one of these days.

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Wood Stoves: Building vs. Purchasing

A lot of people are reverting to burning wood these days, and as long as you have the saws, splitter, truck, and a good back it can pay off. They typically sell for between $5-8,000 and are the free standing outdoor units. Of course you also need a good source for wood and the time involved to make it pay off. If you live in rural America it can be well worth doing. If you live in town, well, that’s a whole different ball game given the current regulatory environment.

Seven years ago, even though we do live in town, I decided to jump to the wood stove market and see what I could come up with. The existing gas boiler system still had the original cast iron radiators and was going to need replaced In the near future. So I did some research and went shopping.

The stove needed to have a small foot print and would have to heat over 2500 sq ft of living area and that complicated things somewhat, but wasn’t really a game changer in the long run. A company by the name of Harman had just what I was looking for, and I bought one of there SF-160 units. The stove is only 2′ square and stands 46″ high. Just what I was looking for.

I poured a slab on the existing concrete for it to sit on and then plumbed it into the loop along side the gas unit which would be used as a reserve unit. I sweated in some additional valves and copper and it made for a very nice setup. The existing chimney (27′ out) was in good shape but I still put a pipe liner in it to be on the safe side of things. I also mounted an 80mm equipment fan in the draft bay and an additional process meter along side the Johnson controls.It amounted to a pretty good chunk of change by the time I bought the Stihl saws and got a splitter built.


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Now lets take a look at the choice to just build something from scratch. Over the years I’ve seen some pretty wild stuff. From 55 gal. drums welded together to well, you name it. On occasion however you run across somebody that does have the skill and expertise to actually put a nice working system in place. We’ll take a look at one of them.

The stove was hand crafted from the ground up and is quite impressive to say the least. It’s a boiler system also and an outdoor unit built with high quality materials with all the bells and whistles. The door alone is made out of 1/2″ steel and latches around a roller bearing, it has both draft and flu controls, and a blower in the system also. All are controlled by individual process controllers which provides for ultimate control of the system. It’s padded with boiler insulation and will have aluminum skin on top of that. Trust me, this guy has just enough engineer in him to make stuff happen, and not enough to muck things up like some do by over engineering. This is quality workmanship from the ground up and it was a blast helping him out on the electrical side of the project.

As to the total cost, well, excluding labor, it was nowhere near what you’d pay for a manufactured stove. So if you’ve got the time and skills it is something to consider.

Nice job E, we’ll give her a shake down cruise this weekend…


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The Arc Flash Incident

This was a very close call and if my timing would have been off by for more than 3 sec I wouldn’t be posting about ittoday. The power generation plant I took care of had two out of the three of these switchgear units built by ABB. They were never put into production due to problems they were having keeping the SF6 gas in them used to suppress arcing.

They made several attempts to rectify the problem to no avail. Basically management dropped the ball on that one and I had no choice but continue using the gear even though they were aware of the safety risks It was a 13Kv system which is highly dangerous even on a good day with good equipment. Neither did they supply the personal gear usually required to work on high voltage systems. In retrospect I should have went thru the legal channels with OSHA, but it would have made quite the stink. The company usually found a way around most of OSHA’s guidelines so I didn’t even bother and needed the job.

I had to roll the gear in and out by hand and every time those knives were opened or closed without SF6 in the switch chambers we were pushing it.

The oilfield had miles of the 13Kv grid and trees threw the lines and other problems were quite common, nothing but hills and trees. On one occasion the field electricians had problems during the night and still hadn’t identified the problem that morning when I showed up. They’d already opened and closed the gear several times and I was next to do it, they watched the shots on the poles outside for signs of trouble. I didn’t know just how close the grim reaper and I were getting at that point.

I was always pretty nervous around the stuff when they had line problems, so zi was tense to say the least. When I rolled the knives in I heard what I thought was on of the HV fuses blow, and instantly headed for the door out of the building. I covered the 15 foot or so as fast as possible and just as I reached the doorway the gear exploded. The blast tossed me face down outside in the rocks. If I’d have hesitated 2 or 3 sec the arc flash would have caught me full on in the face. My instincts proved true that day for sure.

The heavy gauge cabinet top just folded up around the 4″ conduit, blew the doors off and puffed the whole thing like a toad frog.


I was head level with the top of the cabinet when I rolled the knives in (pic on the right). The arc flash alone would have killed me if the doors blowing off hadn’t. Close call for sure.

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This is whats was left of the switch chamber. The shrapnel all missed me.

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PCB Wall Mosaic

I’ll start re-creating some of my previous post with this one. I had a ton of old computers and other electronics stored that I’ve acquired over the years and decided to scrap most of it. It was all disassembled and I recycled the metal, plastic and CRT’s. I already had plans for all of the old PCB’s and this is the end result. Wall art!

All in all it was a major production and quite time consuming but worked out nicely. It kind of adds a little contrast to the Half Baked Studios and worth the effort. I freed up a lot of storage space, and I actually enjoyed the destructive tear downs.

Click on the thumb nails for 1024×768.

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