Another Tiny IC Engine

[b.lindsey]

Well it won't be as long as it has been Don....thanks for checking it, I appreciate the support. Just got to get you working on a new project soon as well.

Bill

[90LX_Notch]

I'm up in the air Bill.  I have few ideas, but nothing is set in stone at this point. 


-Bob

[Kim]

Its looking good Bill! Your pretty handy with that brown stuff too!

I'm sitting in the bleachers with everyone else, waiting for that first run
Kim

[b.lindsey]

A little more work on the brown stuff this evening Kim, had to make an area for the on/off switch and the holes to mount it through the cover plate on the outside of the base as shown in photos 1-4. Then I drilled the two clearance holes for the 2-56 SHCS's that hold the engine to the corian. In photo 5 I had already drilled those and was counterboring from the back side to the screws would be flush with the underside of the corian. Fortunately these lined up perfectly with the holes in the bottom of the engine and the last photo shows it secured by the cap screws. Done for tonight but not done with the base yet, still need small holes in the base frame for the power on and timing LED's and three more holes in the corian top to route the spark plug wire, ground wire, and hall sensor harness through. Oh yeah, at some point the brown stuff will need to be stained and sealed too of course.

Bill

[crueby]

Nice!


Just think of wood as a slightly porous and well annealed brass, it machines nicely. Clear chips often, but no cutting oil!

[b.lindsey]

Rather than just drilling holes through the corian top for the various wires and connections to the engine, I did some sketching of some brass grommets to dress things up a bit. These would be similar to the plastic grommets you see in some desktops for computer wires to go through, just much smaller. The idea is shown in the first .pdf below.  The .470" dimension is the thickness of the corian. The one on the right with the flat side is for the hall sensor harness and will fit right up against the engine just below the hall sensor bracket. The overall layout for the moment is shown in the second .pdf

Bill

[b.lindsey]

Some progress today, more that it looks like but had some other things to get done that cut into shop time. Still had fun though. I was talking about the grommets last night and got them made, not to the full thickness of the Corian as it wasn't needed. Instead they go into it about .250" with a nice snug fit. Nothing special about the process. The finished grommets are shown in the first photo and the second gives some idea of size. In photo 3 I had set up the Corian on the mill to drill the three .250" holes for them to fit in. As I had noted the one for the Hall sensor harness butts right up against the engine base and had to be flatted on one side. The result is shown in photo 4, and the last photo shows the two full grommets located and installed as well on the head end of the engine. I did get the base stained and also the bottom of the Corian drilled and tapped to hole the CDI enclosure. More on that tomorrow.

Bill

[Flyboy Jim]

Pretty clever Bill. Base and grommets came out nice. 

Jim

[Kim]

Those grommets look great Bill!  That kind of detail will really add to the overall 'finished' look of the engine!
Kim

[b.lindsey]

Thanks Jim and Kim. The thing with details is that one leads to another. In this case the plastic witch cover looked rather plain and begged to be made out of brass as well so I did that this morning (photo 1). It is shown installed in photo 2. The spark plug wire and ground wire are shown coming through the grommets in photo 3. This is a straight shot up from the CDI module mounted directly beneath them which was the plan. Since this CDI system will be devoted to this engine both the ground wire and spark plug wire will be trimmed and their connectors soldered on, so there will be minimal slack wire to deal with either above or below the Corian base. Roy in his instructions say to attach the ground wire to the engine itself and not to the screws used to attach the engine to the base, so I will attach that to one of the lower screws holding the cylinder head on. If anyone sees a problem shortening these leads please let me know. Since the CDI system is potted in epoxy, there is no turning back once they are cut. The other detail was to drill holes just below where the switch mounts for the two LEDs, one is an extension of the timing LED built into the CDI box, the other is a pigtail that fits between in the battery/switch/CDI box to show that power is on. This was a bit of luck in that the heads of the LEDs are 1/8" with a slightly larger flange at the base. The thickness of the wood where the switch mount is milled out is approximately 1/8" as well so I drilled two 1/8" holes for the LEDs to press fit into and will secure these at assembly with some clear silicon. This is shown in the last two photos. Another coat of stain was applied to the outside surfaces and the box is complete other than varnishing.

It's getting close now, thanks for the patience.

Bill

[90LX_Notch]

Very classy Bill.  I really like the details.

-Bob

[b.lindsey]

Thanks Bob. I am remaking the governor weight arms this afternoon. Wasn't happy with them, but almost done with that. Had to make a Home Depot run for a couple of things too.

Bill

[gbritnell]

Bill, the most important thing is to make sure that there is a good secure ground. Personally I would have no problem using one of the base mounting screws but to cover all bases and for aesthetic reasons why not drill and tap for a small screw somewhere near the outside bottom of the base, front or side and attach the ground wire there? I just think it will look out of place mounted to the head. Just my two cents worth.
gbritnell

[b.lindsey]

Thanks George. I will take a look at that option. The remake on the governor arms was also worth the time, I am much happier with them now!

Bill

[b.lindsey]

No pictures from last evening but did get the governor weight arms installed and fiddled with that linkage until it was working smoothly. Yesterday I ordered some extension spring stock from McMaster to make the governor springs from and that should arrive probably tomorrow. Meanwhile tonight I will carry on with finishing up the CDI system. The second coat of polyurethane is drying on the wooden base frame now. If all goes well, should be able to give it a try tomorrow evening...keep your fingers crossed !!

Bill