1904 Whitehead Vertical Gas Engine

[Sanjay F]

Steam, flame licker and stirling for me - I am determined to completed an IC restoration before the year is out. I agree with Jason, it's whatever you find interesting or tickles your fancy. I must admit I'm more drawn towards engines where you can see the mechanism in motion - more to look at I guess? 

[Michael S.]

You're right there, Sanjay. It's always nice to see the crankshaft and connecting rod. How boring a model of a Junkers free-piston engine... or a rotary-piston engine... would be.

[Jasonb]

Warning. Not only is this post about IC engines it also contains images of real Iron Castings. Those that may get over excited by this should make sure they are sitting down and that matron is not too far away before reading any further.

The castings arrived in just over 2 weeks which was a lot better than the 6-8 weeks that East Coast Castings had said they would take. The flywheels were very good.



The base was a little rougher than I would have liked on the vertical faces, This seems to be a problem with most foundries using an airset sand as they dump a load in and just ram it down rather than packing it against the vertical faces. Fettling was a bit closer than I would have liked too but I can work with it.



The bottom of the base casting was fairly flat so a quick file and it was clamped down to the mill table and a skim taken off the top of the corner posts and bearing housings, you can see a tiny amount of cill on the bearing housing corner but I had allowed a decent 5mm machining allowance expecting these finer features to be the most at risk of chill.



With some flat surfaces the casting could be clamped down and the bottom face properly machined flat.



Then back up the right way to drill the holes in the hold down lugs



These holes were then used to mount the casting to a machining plate where the posts and bearing housings were milled to final height, holes drilled and tapped and in the case of the corner posts counterbored to accept a spigot on the columns. I also milled out the rectangular pockets for the bearing caps. The vertical pad at the front is to take a bracket that supports the bottom end of the cam shaft.



I did not have the caps cast but instead machined them from cast iron bar, the CNC did the oval oil pockets and a cutter with a 1mm corner radius left a fillet around the pocket so it looked like a casting.



The other side was milled to form a tenon to fit the base.



With the caps screwed into place the machining plate made it easy to set the casting square for boring the bearings. After this the last 1mm was taken off the top of the bearing housings so that the caps would bear down onto the bronze bearings.

[crueby]

 

[Dave Otto]

These photos aren't making since to me, can we see a photo of the complete bearing cap removed from base?
You made a tenon on the bearing cap, and a mortise in the block to receive it, but in the photo where you are boring for the bearing there is no evidence of these features?
Also why would you need to remove a full MM after machining to hold the bearings in place, seems like a bit much? Maybe it will become more clear in future posts.
All looking good by the way.

Dave

[Jasonb]

Sorry Dave, my fits must be too good as you can't see the joint 

Hopefully the following pics will make it clear. You can see the gap between cap and base, I could have shimmed this to machine the bore but chose to leave the base tall and then take the 1mm off after boring. The gap looks about right when compared to the original engraving.

There is another build photo that will show the cap in place and the gap, but you will have to wait

[Dave Otto]

Thanks Jason

That is kind of what what I expected but couldn't see the vertical part line in your photo, could see a little of the horizontal one though.

Dave

[Jasonb]

Not much to say about machining flywheels that I have not said before. Five Spoke layouts are always a pain to hold as you usually can't get 3 or 4 jaws inside the rim without the spokes getting in the way so I mount them on a faceplate with a bit of 6mm MDF between. That way I can completely turn the face, one side, the hub and bore all in one setup. The hub was bored using a piece of the 12mm PGMS that will form the crankshaft as a gauge.



Here they are slipped into position to get a feel for how they will look. The columns have also been made which are just tapered shafts with threaded spigots on the ends.



The cylinder jacket started life as a piece of 55mm dia EN3 and was roughed out to shape, the short spigot on the end will locate in the entablature plate.



With the boring bar held at an angle and coming in from both ends the middle was hollowed out to form the water space



There are two small webs at the base of the water jacket, these were formed on the corner of some 5mm plate and then the mill used to cut them from the plate.



Here they are stood in place on the entablature plate which was cut from over thickness 6mm material, drilled and the central hole bored to accept the cylinder jacket.



The water bosses had there oval profile cut on the CNC, a boring head was used to do the concave cuts to suit the jacket and a holes drilled so they could be screwed in place to solder.





After a pickle the bottom of the entablature plate was faced down to it's final 5mm thickness.



Then the top was faced to length, both ends bored for the liner and although it is hard to see there is a 1.5mm x 1.5mm rebate to take the lip of the liner.



Lastly the water bosses were milled off flat, drilled for water and tapped for the flange studs. I must have drilled and tapped for some cylinder head studs too but did not take a photo.

[Dave Otto]

Good progress!
Will you be using a hot tube, or spark plug?

Dave

[Jasonb]

Hot tube and propane for fuel as well as heating the hot tube.

[Johnmcc69]

Very nice work & design Jason.
 John

[Sanjay F]

So much progress already, looking very nice 

[steam guy willy]

Dave, I'm hoping to run it fast enough to get some steam off the cooling tank

Graham. It would be interesting to try the lost PLA on a more complex casting that might otherwise have needed a core. From what I have seen of other peoples attempts the gasses from the burning PLA can cause problems. Your simple gears would have been a lot easier to vent.

But for parts like the flywheel and base I don't see an advantage in lost PLA over traditional methods where the pattern is removed.

I'll go and search the ME archive to see if I can find what issue it was in. I've also been studying the Boys Own mag these last few days


Hi "J" interesting way to get  X 2  gearing with the same size gears....have seen this before.     good work and progress.
Willy

[steam guy willy]

I thought I saw some bright orange gears being made but looked back and they seam to have v vanished ??!!!!

Willy

[crueby]

I thought I saw some bright orange gears being made but looked back and they seam to have v vanished ??!!!!

Willy

In Reply 9, August 24th!