Doble's Ultimax engine

I found copies of Doble's Ultimax engine online, in electronic form. Most of the drawings are photographed too small to be of use. Does anyone know if hard copies are available?

Dan

[content.cdlib.org]

Is this what you found.


Jeremy

Yup, that's it.

Dan

Dan,

You might try to contact whoever now owns the old McCulloch Corporation in Los Angeles. They should have the master file, if it has not already been trashed.
Abner had copies that his widow later donated to the Bancroft Library at the University of California in Berkeley.

FYI, the Bancroft does NOT own the copyright to any of this Doble material. The photos and drawings were never copyrighted in the first place by the Corporation. Per the late Marc Lothrup, Doble's patent and copyright attorney.

Also FYI, the ULTIMAX and SUPER ULTIMAX engines were based on the Skinner compound unaflow marine engines and the basic idea Abner had went back to the Farquot engine of around 1890, or thereabouts. "The Steam Engine" by Rose, if you can find a copy.

Jim



Edited 1 time(s). Last edit at 02/19/2009 08:50AM by James D. Crank.

Jim:

Found some info on the Skinner engine. So it is essentially two single acting uniflow cylinders in tandem, pushing in opposite directions. Is there a fundamental advantage to this, or is it mostly about eliminating heat losses, keeping the oil cool, etc.?

Dan

For more data on the Ultimax see:


[www.google.com]
[www.google.com]

Regards,

Ken

Thanks!

Dan

Ok, read up on the Skinner engine. So did Doble decide that his prior engines where not optimal, and decide to adapt the Skinner engine to an automobile? Was an actual Ultimax engine built, and did it meet expectations? was it better than prior Doble engines, and do we know if he thought it could be made even better?

Dan

Dan,

Read the first forty pages of the Doble binder that SACA sells, the section on steam engine design. Abner totally evaluated every possible steam engine format, in order to settle on what he thought was the engine with the greatest promise. His reasoning is quite sound.
Remember, Abner was always looking for the lowest possible water rate and the ability to use the highest possible superheat. He often went overboard and ignored the practical aspects and cost.

He didn't adopt the Skinner compound unaflow, or the Ajax. He simply examined every possible design of the steam engine, then combined the best features into one engine, the ULTIMAX and SUPER ULTIMAX.
Seems that Skinner and Ajax also did the same evaluation. All three came to the same conclusion.

From the best information, McCulloch built three of these engines. One went into the Paxton Phoenix car. There is a fine SAE paper you can buy on this project.

Jim

Jim:

Thanks!

Dan

Jim:

Which of the publications are you talking about? the two volumes from Bancroft library microfilm?

Dan

Dan,

Those are the ones.

Jim

Does anyone have leads on where the actual engine(s) that were built might be?



Edited 1 time(s). Last edit at 07/25/2009 11:49AM by mjanssen.

I don't know where the engines are, but the Doble notebooks are available from the SACA Storeroom

[steamautomobile.com]

DNOTE $130.0 Abner Doble's Notebooks un-edited from the microfilm from the Bancroft Library. 2 volume set replaces the former DENG and DGEN. 18 S & H /US, all others contact Storekeeper

Karl Petersen

This has been covered at least ten times in the past. Too bad we don't have a yearly updated index to the SACA Newsletter so people can easily look stuff up.

McCulloch sent one engine to the Navy at Point Mague for trials in a boat. One was installed in a Ford chassis and we saw the film at a SACA meet in Oxnard years ago. That one may have been the one sent to the Navy later on. The other two engines and the parts (?) were supposedly in a warehouse at the McCulloch plant. Never able to trace them down and McCulloch's corporate people are no help at all. I think McCulloch was bought up by some other aerospace company years ago.

Get the SACA binders, because that may be all anyone will ever see of this final engine design by Abner. Both the ULTIMAX and the SUPER ULTIMAX are covered.
His reasoning in the first 40 pages is as sound as one can get and he described why he abandoned his pet reheat triple and piston valve concepts and went to the poppet valve ULTIMAX-SKINNER-AJAX design. Actually based on the Farquot engine as described and illustrated in "The Steam Engine" by Rose. I have a copy and it's hard to find.

Also, get the SAE paper by Jim Dooly and Allen Bell, it has all the information in it.

Thank you, Jim.

I got the materials you suggested some time ago, but did not see a reference to where the actual hardware was.

I appreciate you repeating it.

Regards,

Matt

Hello Jim,

Jim, what's your take on a feature of the Ultimax engine design which uses feed water to cool the cylinder walls? I was looking at this for similar reasons of providing cylinder cooling for good lubrication. Also, if worked right, there is a possibility of getting some regeneration out of such a system.

Best, ---- Bill G.

Bill,

In the Super Ultimax engine, if you carefully read his notes, he wants very high superheat. In the engineering notebooks he talks about 1200°F-1400°F. The cylinder oil will not stand this, so he cooled the cylinder walls with feedwater. He says in his notes that 550°F wall temperature is as high as the oils will stand.

There is some mention in the notes that the Super Ultimax was adapted to act as a triple expansion engine with the addition of one more valve. I see nothing to say that McCulloch ever built this version; but stayed with the compound Ultimax. Abner was always pushing the limit as far as he could.

My take on this is very simple. I will go to any length to avoid using cylinder oil. The problems it introduces are endless.
Harry took the same approach and is successful in water lubed piston rings.

Jim

Thanks Jim,

Harry goes to about 1,200 + degrees F inlet steam temperature last I heard anyway. The Peek rings would not take too much higher a temperature than a good oil might. There are some possible alternatives to Harry's system that I see but since he has already worked out something with the Peek rings as he has developed them, they should be a good thing to use. Still the cylinder walls would need to run around 550 or so degrees to keep from melting the Peek.

Harry uses a regeneration of sorts with coils wrapped around the cylinders, as I understand, to cool the cylinders.

I have been kicking around the idea that standard piston rings designed for IC engines are just not sufficient for a steam engine. I hear too much about leakage damaging efficiency. I am thinking that a gapless Peek type ring would be a better way to seal. This ring would use the cylinder pressure to maintain the ring seal against the cylinder wall but a little differently than an IC ring does. The ring would have to have an internal spring within it to initiate the seal and be mounted to the piston in such a way that no steam would pass between the ring and the piston proper. A really hard and smooth, slippery coating on the cylinder walls should provide enough lubrication and wear resistance.


Now Harry says that water lubricates the engine with the Peek bearings. How though do the rings get water for lubrication as the cylinder walls would be too hot for liquid water? They must be running dry.

Best Regards, ---- Bill G.

Bill,

Take some time and consider two things.
1) Inject water onto the rings at the bottom of the stroke after the exhaust ports have opened. At BDC when the temperature and pressure are at the minimum..
2) Who says one has to use metal cylinder liners? We have good ceramics today that could replace metal. A liner and not a cylinder, because at very high pressures, the metal cylinders will survive the pressure. One needs them to back up the ceramic liners. You have to match the temperature expansion coefficient though, and this gets tricky.

To be competitive, the Rankine cycle engine has to see a great increase in power density and net cycle efficiency. Both come from very high steam temperature and operating pressure. All of this takes cubic money to develop and Harry has done it.
Any cylinder lube oil puts a cap on the cycle efficiency, as it becomes carbon all too easily.

There is an awful lot of materials now available from the aerospace and gas turbine worlds that can be used in a steam engine.

I used to think it was great fun to design and lay out such engines. Now I abandoned that idea and only support Harry.

Fun, ain't it.

Jim



Edited 1 time(s). Last edit at 09/13/2009 11:17AM by James D. Crank.

Yes Jim,

It is some fun, is Harry getting the same numbers, 30% with a closed condenser, as with open condenser. I see Harry toting a 50 million dollar market for the WHE engine, can you support this?

Jeremy