1/4 Galloway Hit and Miss engine

[marksavoca]

The casting has the basic shape.

IMG_5270 by Mark Savoca, on Flickr

Started by cleaning up the end

IMG_5273 by Mark Savoca, on Flickr

I then surfaced and drilled the mounting hole and cut of the extra on the other end.

IMG_5284 by Mark Savoca, on Flickr

IMG_5287 by Mark Savoca, on Flickr

The governor weight mounting bolt

IMG_5290 by Mark Savoca, on Flickr

Drilling the mounting hole in the flywheel

IMG_5275 by Mark Savoca, on Flickr

Sitting in place. I cleaned it up some on the sander, but left it fairly rough.

IMG_5292 by Mark Savoca, on Flickr

IMG_5295 by Mark Savoca, on Flickr

IMG_5296 by Mark Savoca, on Flickr

IMG_5305 by Mark Savoca, on Flickr

 

[Walsheng]

Looking good. Watching and learning.

John

 

[marksavoca]

Started with 1/2" blank

IMG_5323 by Mark Savoca, on Flickr

Added 45 deg chamfer and used the parting tool to create the small stub on the face.

IMG_5326 by Mark Savoca, on Flickr

Drilled for the retaining clip

IMG_5329 by Mark Savoca, on Flickr

One intake valve

IMG_5331 by Mark Savoca, on Flickr

With the spring retainer

IMG_5575 by Mark Savoca, on Flickr

The two valves

IMG_5573 by Mark Savoca, on Flickr

 

[marksavoca]

When I machined the head, I used a drill bit to create the chamfer for the valves. You can see on the left seat the 'chatter' from the bit.

IMG_5653 by Mark Savoca, on Flickr

To get this smooth and to seal, I used some valve grinding compound and a drill.

IMG_5659 by Mark Savoca, on Flickr

On a very slow speed I used the drill and compound to polish the seat. I oiled the shaft and you need to be very careful not to get the compound anywhere other then the seat.

IMG_5661 by Mark Savoca, on Flickr

Much better

IMG_5673 by Mark Savoca, on Flickr

 

[marksavoca]

I am using 1" 'black' pipe to make the rings. I'm not sure how pipe is dimensioned, but the 1" npt is the perfect dimension for the piston (1.312 diameter).

IMG_5584 by Mark Savoca, on Flickr

Surfaced the inside dimension to the a couple of thousands less than the dimension of the piston ring groove. The outside dimension matches the cylinder dimension.

I parted off three, just in case...

IMG_5591 by Mark Savoca, on Flickr

Sitting in the cylinder

IMG_5588 by Mark Savoca, on Flickr

Used hacksaw and vise to cut.

IMG_5595 by Mark Savoca, on Flickr

IMG_5597 by Mark Savoca, on Flickr

After some googling I decided to use the screwdriver method. I gently slide the ring onto the screwdriver and heated it evenly until it fell off.

IMG_5682 by Mark Savoca, on Flickr

IMG_5685 by Mark Savoca, on Flickr

You can see it is now set to the slightly wider dimension.

IMG_5688 by Mark Savoca, on Flickr

Carefully onto the piston

IMG_5642 by Mark Savoca, on Flickr

 

[marksavoca]

Now that I have piston rings and valves, I wanted to make sure the compression was good and valves did not leak.

Before I seated the valves I did a similar test and the valves leaked badly.

My basic test was simply using my fingers over the intake and exhaust to feel pressure and/or vacuum.

After the valves were seated you can see/hear the intake valve being sucked open.

These are temporary springs and wire to hold the retainer, no gasket and just a couple of head bolts.

Here is a video of the test.

IMG_5681 by Mark Savoca, on Flickr

 

[Petit]

Looking forward to seeing how this one progresses, i absolutely love Hit and miss engines n really want to build one but im kinda apprehensive at the minute.

 

[marksavoca]

Pretty straight forward. Mounted it square in the mill.

IMG_5772 by Mark Savoca, on Flickr

IMG_5775 by Mark Savoca, on Flickr

To drill from the pocket into the top of the cylinder, I used wood spacers for the 50 deg and 6 deg angles. Used a wood clamp because I am only drilling.

IMG_5781 by Mark Savoca, on Flickr

Looking into the end of the cylinder.

IMG_5787 by Mark Savoca, on Flickr

View from the pocket.

IMG_5790 by Mark Savoca, on Flickr

I'll drill the two holes to mount the ignitor, after I have it completed.

 

[marksavoca]

Make sure you have read the earlier comments about the ignitor and how to add the additional adjustable stop.

The ignitor starts as a pretty rough casting.

IMG_5695 by Mark Savoca, on Flickr

I first mounted it with the outside and used the dial indicator to get it as centered as I could.

IMG_5702 by Mark Savoca, on Flickr

I then machined what will later become the inside of the ignitor so I can turn it around and hold it more firmly than the rough casting.

IMG_5704 by Mark Savoca, on Flickr

Once turned around I machined the outside diameter.

IMG_5710 by Mark Savoca, on Flickr

Over to the Mill

IMG_5736 by Mark Savoca, on Flickr

You can see the layout for the two holes that will hold the fixed and moveable shafts.

IMG_5739 by Mark Savoca, on Flickr

A little hard to see, but I milled the right side flat so I can later attach a small arm that will act as a stop. The fixed and moveable shaft holes drilled.

IMG_5745 by Mark Savoca, on Flickr

To machine the inside of the moveable shaft, I first tried to Loctite a 1/8" shaft in the whole that I could then mount in the lathe. After a little time on the lathe the shaft started to bend. So I heated it up and removed the shaft and went back to the trusty 4 jaw. I used a temporary shaft to make sure it is centered.

IMG_5754 by Mark Savoca, on Flickr

IMG_5758 by Mark Savoca, on Flickr

IMG_5760 by Mark Savoca, on Flickr

The body

IMG_5765 by Mark Savoca, on Flickr

The moveable shaft

IMG_5801 by Mark Savoca, on Flickr

IMG_5804 by Mark Savoca, on Flickr

Sitting in place

IMG_5819 by Mark Savoca, on Flickr

For the insulator on the fixed shaft I used a block of plastic and the four jaw.

IMG_5821 by Mark Savoca, on Flickr

Getting it roughed out

IMG_5823 by Mark Savoca, on Flickr

The basic part. You will see that I still need to bore the larger end.

IMG_5827 by Mark Savoca, on Flickr

To bore it, I inserted a drill bit to stop the chuck from crushing it and mounted it back in the lathe.

IMG_5828 by Mark Savoca, on Flickr

Looking carefully you can see the bit.

IMG_5830 by Mark Savoca, on Flickr

I don't have any small boring bits, so I used a drill bit to bore the end. The inside will be tapered vs flat, but I think it will be ok.

IMG_5832 by Mark Savoca, on Flickr

A not so great picture of the completed insulator.

IMG_5835 by Mark Savoca, on Flickr

Onto the fixed shaft. It is about an inch long and only .099 in diameter. Rather than using the follower, I machined it in a couple of stages. Sliding it out from the chuck each time.

IMG_5841 by Mark Savoca, on Flickr

I then could thread the end of it. Using the chuck in the tail stock to keep the die perpendicular.

IMG_5843 by Mark Savoca, on Flickr

IMG_5844 by Mark Savoca, on Flickr

Like the insulator, I turned it around to drill for the point. Was careful to not hurt the threads.

IMG_5847 by Mark Savoca, on Flickr

The parts so far

IMG_5849 by Mark Savoca, on Flickr

Sitting together

IMG_5852 by Mark Savoca, on Flickr

IMG_5857 by Mark Savoca, on Flickr

 

[marksavoca]

@Jasonb @gbritnell, How did you attach the points? What did you use for points?

Jason I think you said you used 3/32" TIG electrode. Would you recommend that still?

Anyone have suggestions?

 

[Jasonb]

Yes I used 3/32" tig electrode silver soldered (silver braze) to the other parts, have used it a few time since and if I could have found my length of rod would have used it again at the weekend You may need the next size down on your smaller engine.

You need to used something like a Dremel cut off disc to cut it and grind to shape.

 

[marksavoca]

More work on the ignitor.

Up next is the clamp. Starts with a small block machined to the outer dimensions.
IMG_6033 by Mark Savoca, on Flickr

IMG_6029 by Mark Savoca, on Flickr

IMG_6030 by Mark Savoca, on Flickr

Drilling and tapping the mount for the ignitor return spring

IMG_6031 by Mark Savoca, on Flickr

I used a dremel cutoff blade in the mill to cut the slot.
IMG_6036 by Mark Savoca, on Flickr

IMG_6039 by Mark Savoca, on Flickr

Sitting in place
IMG_6051 by Mark Savoca, on Flickr

Up next is the ignitor handle
IMG_6056 by Mark Savoca, on Flickr

IMG_6098 by Mark Savoca, on Flickr

IMG_6100 by Mark Savoca, on Flickr

IMG_6103 by Mark Savoca, on Flickr

Created the piece that will be soldered on and become the stop.
IMG_6104 by Mark Savoca, on Flickr

Soldering up the parts.

IMG_6105 by Mark Savoca, on Flickr

After soldering
IMG_6106 by Mark Savoca, on Flickr

I did not like the way the first movable shaft came out, so I rebuilt it. This time I used 1/8 drill steel and machined a separate ring to hold the point.

IMG_6140 by Mark Savoca, on Flickr

Next I turned a piece of scrap to resemble the size and shape of the movable shaft with the hammer to use for making the torsion spring. You will notice that I put a 90 deg bend in the piano wire and clamped it in the three jaw with the template.

IMG_6288 by Mark Savoca, on Flickr

Partially assembled
IMG_6295 by Mark Savoca, on Flickr

Used the same plastic to create a small washer for the fixed point.
IMG_6417 by Mark Savoca, on Flickr

Laid out the terminal plate.
IMG_6420 by Mark Savoca, on Flickr

Drilled and cut with tin-snips to rough shape. Then to the sander.
IMG_6423 by Mark Savoca, on Flickr

IMG_6424 by Mark Savoca, on Flickr

The completed ignitor assembly
IMG_6433 by Mark Savoca, on Flickr

IMG_6438 by Mark Savoca, on Flickr

IMG_6447 by Mark Savoca, on Flickr

IMG_6450 by Mark Savoca, on Flickr

 

[Cogsy]

A lot of work in such a small piece! Your soldering setup intrigues me - how much flame and smoke do you have to put up with from the wood while you solder?

 

[marksavoca]

Up next is the mixer.

After studying the casting, I determined that I could not use the drawings. Several of the dimensions were smaller than the casting. I'm not sure if I received the wrong casting or not.

The most critical dimension seemed to be ensuring the small port is in the center of the valve seat.

The casting
IMG_6516 by Mark Savoca, on Flickr

Following the other great examples, I first turned the one end that would be used for turning the rest.

IMG_6519 by Mark Savoca, on Flickr

I then turned it around and parted off the bulk of the end. This will be used later.

IMG_6522 by Mark Savoca, on Flickr

After drilling the center, I took it to the mill to machine the other two ports.
IMG_6541 by Mark Savoca, on Flickr

I then drilled the air inlet until it hit the center.

IMG_6546 by Mark Savoca, on Flickr

I drilled and tapped the fuel inlet. This gives me the reference for how deep to drill the cavity for the needle valve.

I then drilled and tapped the cavity for the needle valve.
IMG_6546 by Mark Savoca, on Flickr

IMG_6574 by Mark Savoca, on Flickr

I then drilled the small port until it hit the center.

This allowed me to put it back in the lathe and slowly drill until the small port is in the middle of the valve seat. I used a 90 deg bit to finish the valve seat.

IMG_6584 by Mark Savoca, on Flickr

You can see the small port in the middle of the valve seat.

IMG_6586 by Mark Savoca, on Flickr

I used a home-made bit to turn in a small relief as indicated on the diagram.

IMG_6591 by Mark Savoca, on Flickr

The completed end.

IMG_6599 by Mark Savoca, on Flickr

 

[Walsheng]

You are sailing on this build. I started mine months before you did and you passed by me a while ago. Looking good!

John

 

[marksavoca]

Next is the coupling

IMG_6608 by Mark Savoca, on Flickr

Using the tail stock to keep the die square.
IMG_6609 by Mark Savoca, on Flickr

Once it was threaded I drilled it out.

IMG_6611 by Mark Savoca, on Flickr

To thread the other side a created a fixture, a nut if you will, to put into the chuck without hurting the threads.

IMG_6616 by Mark Savoca, on Flickr

Up next is the glad nut

IMG_6618 by Mark Savoca, on Flickr

IMG_6623 by Mark Savoca, on Flickr

The mixer valve
IMG_6630 by Mark Savoca, on Flickr

IMG_6635 by Mark Savoca, on Flickr

IMG_6638 by Mark Savoca, on Flickr

The valve guide
IMG_6640 by Mark Savoca, on Flickr

Sitting in place

IMG_6644 by Mark Savoca, on Flickr

The valve
IMG_6700 by Mark Savoca, on Flickr

IMG_6703 by Mark Savoca, on Flickr

Like setting the valves in the head, I used the cordless drill and valve grinding compound.

IMG_6708 by Mark Savoca, on Flickr

The valve, guide and spring in place.

IMG_6712 by Mark Savoca, on Flickr

Looking down onto the valve

IMG_6713 by Mark Savoca, on Flickr

 

[marksavoca]

Mixer Cap. I first turned the outside dimension in the lathe, then went to the milling machine and rotary table.

IMG_6718 by Mark Savoca, on Flickr

IMG_6724 by Mark Savoca, on Flickr


IMG_6727 by Mark Savoca, on Flickr

IMG_6731 by Mark Savoca, on Flickr

IMG_6732 by Mark Savoca, on Flickr

IMG_6733 by Mark Savoca, on Flickr

Again, using the tail to keep the die square.

IMG_6735 by Mark Savoca, on Flickr

IMG_6760 by Mark Savoca, on Flickr

I used the rotary table to drill the 4 thru holes.

IMG_6759 by Mark Savoca, on Flickr

Completed and in place.

IMG_6765 by Mark Savoca, on Flickr

Laying out ratchet spring

IMG_6767 by Mark Savoca, on Flickr

Cut out

IMG_6769 by Mark Savoca, on Flickr

After a little time on the sander and some bending. I used a small punch to make the dimple.

IMG_6772 by Mark Savoca, on Flickr

In place. You will notice I had to add a small washer. I couldn't cut the threads close enough to the center for the nut to get tight.

IMG_6780 by Mark Savoca, on Flickr

IMG_6781 by Mark Savoca, on Flickr

For the fuel inlet, I needed to create a 3/16 mpt to #6-32.

IMG_6786 by Mark Savoca, on Flickr

IMG_6787 by Mark Savoca, on Flickr

Sitting in place

IMG_6791 by Mark Savoca, on Flickr

Exploded views

IMG_6801 by Mark Savoca, on Flickr

IMG_6804 by Mark Savoca, on Flickr

Two of the more detailed components!

IMG_6828 by Mark Savoca, on Flickr

 

[gbritnell]

A suggestion Mark,
Use the lightest spring possible on the valve. Gravity along with a light spring is all that's required to close the valve.
gbritnell

 

[marksavoca]

Thanks, I'll do that.

How about the intake and exhaust valves. I have some that match the specifications, but they seem pretty stiff.

 

[marksavoca]

It's been a little while since I posted, so I'm catching up again.

Mounting the water hopper to the cylinder. Pretty straight forward, 4 thru holes and 4 tapped holes.

IMG_6831 by Mark Savoca, on Flickr

IMG_6833 by Mark Savoca, on Flickr

IMG_6835 by Mark Savoca, on Flickr