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Steve Peirce,     Uniontown, OH    revspyder1@earthlink.net            3/30/2003

This page documents Steve building this engine and taking it to NAMES and getting a award and cash prize for his craftsmanship.  This is truly a major accomplishment.  David.

The engine and work in progress pictures.

  I needed a break from the "Hurricane" So I decided to build a nice "Little" "Simple" project to release some of the stress from racking my brains to complete the "Hurricane"
So, I decided to build another "Flame Eater" engine as these are nice simple engines that require little more then an alcohol lamp to operate. No complex calculations on Dwell time, or intake and exhaust valve spring tension. No Piston rings or tricky mechanisms to fool with, just simple function. A wonderful stress free quick project.
  And So............................  The "Husky" was born.
 The "Husky" is an air cooled, center crank vacuum engine. Based on Jerry Howell's "Side shaft Vacuum Engine" with a few modifications. Some out of personal preference and some out of necessity!
Pictured here with my new Company Salesman "Uncle Jack", is the start of the cylinder, frame and Crank Discs.

Once I had the Basic Frame and Cylinder done I started on the Belt Driven Cooling fan. I made several fan blades as wasn't sure how they would work out and I wanted a few on the side just in case.
 
Next I went ahead and machined the piston connecting rod and started working more of the final frame shape. The original plan was to press fit the Crank Shaft together in a solid frame with Precision Ball Bearings, but was later changed to a more interesting idea. I didn't take any pictures of Lapping the cylinder and really should have! I have never lapped a brass cylinder before and My "Mule" Side shaft Vacuum engine runs very well with out being lapped. I decided when it came time to start the engine the first time I would need to lap the cylinder, but how to do it was a question. I didn't have stock and tooling to make a lap for a cylinder of this size and at a last minute decided to try something different. I took a piece of brass thin wall tubing a little larger then the bore and cut an 1/8 inch slot from end to end and squeezed it down into the cylinder with a mixture of Grease, Oil, and Brass-O. Since I had no way of holding a lap of this type in a chuck I chucked the cylinder in the lathe and did it that way. It worked out very nicely! If anyone knows of a reason this is not a good idea, or it is a good idea, I would love to hear comments.
  I decided on Delrin for the crank bushing and the Wrist pin bushing, Although I had not thought far enough ahead to the heat the wrist pin would be taking.  After several hour now of heat the wrist pin bushing has had no visible signs of damage.

In the picture below you can see the Valve workings and the interesting idea for the Crank I mentioned earlier. Instead of the crank being assembled in the frame. I decided to press fit bronze bushings over the bearings, assemble the crank, bore the frame holes to the exact size of the bearing bushings and mill .100 short of half way off the frame. This idea was also a smashing success ! any comments welcome ! This makes for a tight snap fit, much like a toy truck axle and so far with being snapped in and out several 100 times during engine testing has held up very well and if need be the bushings could be locktighted or soldered with low temp solder.
  I decided to go a little different route on the valve mechanism and eliminate the need for a small spring and a small piece of steel shim stock was used instead to maintain pressure on the valve plunger. All of the 11 parts of the completed crank are press fit together. Why 11 parts. well the bearings I salvaged out of a computer cooling fan were metric and the steel brazing rod axle was standard, so a brass tube was press fit over the axle to bring the size up to meet the bearing ID. The connecting rod journal is hardened drill rod salvaged from the computer's hard drive , plus the bearings and bushings. A Lot of parts for a crank I know !

Next we see "Uncle Jack" with the engine a little farther along. I am really beginning to like doing my flywheels of different materials, I think it's becoming my trade mark!
The Flywheels were made from bronze rings press fit over aluminum centers to add centrifugal force and momentum with out the full weight of Solid Bronze .
 Here we see once again that we at the "Maxum Motor Company, Stand Behind Everything We Build" and after many days of trial and error testing, re-engineering, repairing , fool proofing, and just plain dealing with the "Temperamental Nature" of small engines. The engine has several "Short" Minutes of run time! I had a great deal of trouble with the valve arm flipper breaking loose and loosing the timing of the valve, and some trouble with heat expansion causing the valve arm to loosen and drop off the front of the engine as well. But, after grinding a small flat on the valve rod for the set screw on the Hub to grip the arm stopped falling off. Another flat on the other end and some soft solder so far has ended the flipper problem as well. and when she feels like running , she really runs! During the first few runs she has maintained a good 1200 RPM and sounds something like a small Chainsaw. She really screams!

This next picture is of the "Maxum Mule" side shaft Vacuum engine and "Husky" together give you a better idea of what it looks like !
The glass cylinder oiler and small grease cups for the crank are done but not on and my camera will not focus on them despite many attempts and the engine is now disassembled and being painted. The cylinder and head are being blacked with Brass Black and I will post more progress when I get to it.
  Enjoy!
 Steve P. Uniontown, Ohio

4/4/2003

 

   

4/7/2003 

Since I couldn't find a saw blade commercially made. I Made myself a Saw Blade from Aluminum. Since it will not be doing any real cutting, I preferred it not be very sharp.

I started out with a .025 thick disc . Set it up in my turn table and cut the teeth in two passes at different angles. A slight mis-calculation made the teeth a bit meaner then I had planed, but they look very efficient!

   

 4/18/2003   I decided on a Belly Tank and Burner for the Fuel System. After Many, Many Hours of bouncing ideas around I finally decided this was the best way to go. The Burner sits down in a ring
on the top of the Tank sealed with a rubber "O" Ring. The handle on the burner allows the distance from the flame and head to have some adjustment as it will travel on an arc in front of the valve.
Once in place only the burner and fill tube will be visible. A small wooden handle will be added to the burner arm and a nice polished brass fuel cap will be added.
Next it's back to finishing up the Saw and with any luck will be completed in time to show at NAMES.

  Test burn completed. I was a little worried , due to size, that the burner might get warm and Vaporize the fuel. After the initial 10 minute burn, with the flame at max height the burner was less then warm to the touch. Everything works as it should , so far . Heat is On with only a week until NAMES Chips are Really Flying NOW!
 

 4/21/2003   Last update before Names.
  Saw table is almost finished, just needs paint and the springs installed. The table is spring loaded so when it is pushed in to the blade it will spring back out. The belt is on and made from a piece of cassette tape. X-mas music I believe. All that is left is the saw blade safety guard.
  Unfortunately it is not running at this point. I spent a good 4 hours trying to get it started today, but when I brass blacked the cylinder it formed some scale on the fins that flaked off and as I feared it also scaled a small portion of the cylinder wall. I just don't have time before NAMES to lap the cylinder, make a new piston and get it painted and polished in time, so it will have to wait until I get back. After many hours of playing I did have it running very well and as usual paint and polish always seems to effect these engines. Even my "Mule" is a pain to get tuned in after I polish it up for a show.

 4/22/2003   Completed the Husky This morning ! Hooray!

     

 

 

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