Chris's Holly Pumping Engine Build

[crueby]

If I were faced with the problem of mounting those bolts I'd first touch the bolt head with a center drill to make a locator spot for the dental tool.  Then I'd wrap a few turns of thin sewing thread around the bolt.  The idea is to set the bolt in the threaded hole and keep it erect with the dental tool (as you were doing), then pull the sewing thread to (hopefully) get the threads started.

Brilliant!  Got to remember that one for next time.   

[Roger B]

I'm still following and enjoying seeing your solutions to the various problems        I liked your use of the 3 jaw chuck for the 'oversize' drills   

[paul gough]

Hi Chris, Been catching up with your thread and noticed you talking about the brass bed Sherline and giving Austria as its place of manufacture. This is incorrect, actually made in Australia, first by the inventor Harold Clisby and then taken over by Ron Sher, hence the name Sherline, it then passed to the current manufacturer in California who kept the name. Somewhere I saw a photo of Clisby showing Joe Martin his 2 1/2 centre height lathe but as far as I know nothing came of it. Regards, Paul Gough.

[crueby]

Hi Chris, Been catching up with your thread and noticed you talking about the brass bed Sherline and giving Austria as its place of manufacture. This is incorrect, actually made in Australia, first by the inventor Harold Clisby and then taken over by Ron Sher, hence the name Sherline, it then passed to the current manufacturer in California who kept the name. Somewhere I saw a photo of Clisby showing Joe Martin his 2 1/2 centre height lathe but as far as I know nothing came of it. Regards, Paul Gough.

Hi Paul - you are 100% correct, I mistyped Australia and it came out Austria - my goof! 

[crueby]

I'm still following and enjoying seeing your solutions to the various problems    I liked your use of the 3 jaw chuck for the 'oversize' drills 

I have not had to do that often, but it does work for the longer drills and taller parts, since the 3 jaw is shorter than the regular drill chuck and its adapter base, plus the drill shank can go through the chuck center hole. Just enough for that extra fraction of height!

[crueby]

Yesterday afternoon got a start on the piston - trimmed the rod to length, cut in a shoulder, and threaded the end of it 10-32. The head was turned from the brass disc that I had used for holding the cylinder with the live center. It looks very thin, but at 1:32 scale it works out to 12" thick on the original, the originals used pairs of metal piston rings, I am using one viton ring. Snuck up on the groove depth till the cylinder would slide on - without any oil it was sticky, but with a little oil it is a nice slip fit. I'll run in some grease before final assembly.The head was threaded also, with a recess for a retaining nut. All assembled with high strength loctite and left overnight. This morning cut the groove.

And assembled back on the model along with the bottom cylinder gasket, made earlier from thin viton sheet. The OD will be trimmed off with a fresh exacto knife after assembly.

Before running in the bottom screws, I am attaching the top cap - much much easier to do those with the cylinder in hand than with the screws upside down on the model. The socket wrench can get the screws in about halfway, then the lower moulding gets in the way, and requirees finishing up with an open end wrench. Lots of times. I am running them in to just touch all the way round, then will come back and alternate sides like you do with car lug nuts to draw up the gasket compression evenly.

Once the top cap is all on, will add some lube to the bore and assemble it onto the base cap - that will be a longer process, having to do everything in place atop the model....

[Dan Rowe]

Chris one of the Sulzer engines I worked on had 12 0r 16 cylinder head studs. These are 100mm studs and we used the biggest impact wrench I have ever seen to take them up. The procedure was to mark one of the flats of each nut with a magic marker on the head. The giant socket had degree marks so the first time we took the nut up half a flat then to the opposite nut for half a flat. The second pass took the nut up the second half of a flat. We needed the crane to move the impact wrench safely because of how much it weighed. Good thing we did not have to use a torque wrench we would not have been strong enough to lift or work it. 

Cheers Dan

[crueby]

Chris one of the Sulzer engines I worked on had 12 0r 16 cylinder head studs. These are 100mm studs and we used the biggest impact wrench I have ever seen to take them up. The procedure was to mark one of the flats of each nut with a magic marker on the head. The giant socket had degree marks so the first time we took the nut up half a flat then to the opposite nut for half a flat. The second pass took the nut up the second half of a flat. We needed the crane to move the impact wrench safely because of how much it weighed. Good thing we did not have to use a torque wrench we would not have been strong enough to lift or work it. 

Cheers Dan

Long way from the tiny wrench I am holding with two fingers!!

[crueby]

All the screws holding the top cap are in and tight, and the gasket trimmed back too

So on to the bottom cap - got the cylinder greased up and six screws pushed through the flange and gasket, tightened them down a little, and set the rest of the screws in place with the socket wrench - as with the top end, the socket can only get them on partway before it hits the ring above the bottom flange.

One quadrant run in but not to final tightness with the open end wrench. Looks to be about how many I can do without a break to let the fingers/wrists rest.

Running the flywheel around at this stage shows the valves seel pretty well, had to tip the valves over to open position otherwise I could feel the resistance from the compression bogging it down. Thats a good sign! I have the ends of the valve rods nicked with a jewelers saw to show me the positions of the flats, that is just visible in the last photo.

[mklotz]

I'm forced to wonder if a rubber wheel powered by a drill motor or Dremel could spin the screws most of the way in from the position where the socket hangs up.  Then do the final tightening with an open end wrench.

[Admiral_dk]

You can call it experience or laziness - but I'm sure the I would have tried to turn the crank after 4 bolts some 90 degrees apart - I have seen (many more times than I care to remember) that I have forgot a simple detail, that should have been installed first - that shows up the moment I try to see if it will work as i should 

Like most of the rest here I really like the look of fresh cut 'Red-Metals', but on a model like this, it really makes a difference, that you have painted it before assembly 

[crueby]

I'm forced to wonder if a rubber wheel powered by a drill motor or Dremel could spin the screws most of the way in from the position where the socket hangs up.  Then do the final tightening with an open end wrench.

Would have to be just the right hardness and diameter to squish down on the sides of the 2-56 hex but not get chewed up by them.... Hmmmm... by the time I could figure that out I'd be done with the model, though I'd have it for next time. The socket can get the screw just below the lip of the flange by tipping it some, but at that point it skips off the edges of the hex. Some variant of the pin-filled sockets they make for multiple sizes in one socket, with one side cut away and a recirculating holder for the pins. Or a mini track plate drive. Or something.  Now my head hurts.  And my Cuckoo clock just chimed in from the other room!

Could be your next invention Marv!    I'd buy one.

[crueby]

You can call it experience or laziness - but I'm sure the I would have tried to turn the crank after 4 bolts some 90 degrees apart - I have seen (many more times than I care to remember) that I have forgot a simple detail, that should have been installed first - that shows up the moment I try to see if it will work as i should 

Like most of the rest here I really like the look of fresh cut 'Red-Metals', but on a model like this, it really makes a difference, that you have painted it before assembly 

I did turn the crankshaft just holding it in place with no screws in, and again after the first six, just to make sure it didn't want to shift sideways from the piston movement - that all was fine so I ran more in. After that, it was enough to hold pressure too.

And yes, before starting any I sat there for a while wondering what framistat or gizmotron needed to be put in first! So far I haven't thought of any, so I'm hoping! 


And I have not heard any shop elves screaming to get out from inside. Gotta go to their break room and count them...!

 

[crueby]

Today is plumbing day on the Holly engine

Making up the piping to go from the exhausts of the first two cylinders and the inlet to the middle cylinder. Have some bits started for the LP, but wont finish those till it is made.
The valves in the pictures are for the inlet to the IP and LP cylinders - since I am running this engine in 'simple' mode without using the compound action (only running on compressed air, if I ever get a boiler suitable for steam running it, and can lift the engine to get it outside for that, I can replace a few of the piping bits) the input air will be sent to all three cylinders. The extra two needle valves will be used to balance the power output from each, which will be different with the different piston diameters. This extra piping will be hidden in the receiver tanks, yet to be made.
So, when the piping is complete, next up will be to make the crank arms for the IP valves. The eccentric followers were made a while back at the same time as the ones for the HP cylinder, since they are all the same.

[cnr6400]

 

Be sure to engrave "FECIT PLUMBUS MAXIMUS" on a pipe where it won't be seen inside the receiver - so the archaeologists of the future can tell which ancient Roman plumber did the pipework.....