Baker Fan

• Baker fan plans

As suggested earlier, I assume the Baker fan was originated by the Baker company for testing their steam engines. Steam engines have much larger drive pulley's than our tractors, and generated more hp than many tractors with pulley's. I'm not sure how well a Baker fan built to original specs would work for a JD 720, for example. Several shows have them, and some experience from them regarding paddle and drive pulley size might be quite valuable to keep from re-inventing the wheel. My 0.02 only.

Sorry for the long post, just thinking out loud.

\\\\Maybe a design that allows for 2 of the paddles to be removable would allow it to be used for say a JD H or IH C up to a JD 80-830 or IH 650.\\\

How about some type of sliding panel arrangement so that you could adjust the panel surface area depending on the power input. (big panel=high hp tractor, small panel= small tractor). Just slide the panels out a few inches at a time using stop pins. Ideal would be a governor operated slat affair wo that the fan rpm would add panel surface area as it attained overspeed, and trim it back at underspeed.

Also, I've been doing some research on the Prony Brake type of dynamometer. I'm wondering if these might actually be a bit easier to build.

I looked at the rearend of my VAC Case tractor today, and pondered this design:

Take a junk VAC, transmission on back, strip the tires from the rims. Build two wooden block strap brakes for the rims. These would be tied together through a linkage, and then to a scale if torque readings are desired. The differential would make certain the brakes were loaded equally (the lighter turning wheel would try to turn faster, drag harder and slow until it "equalled" the load of the other wheel).

Two plastic tanks, like tire leak testing tanks, would be provided under each wheel, and would allow the rim to dip about 15-20% into the weater bath for cooling.

Now you input the power through the transmission driven powershaft at the rear. You could shift the transmission through any of the four gears to provide ranges of load if required. The direction would be reversed because of the pto rotation, but that shouldn't matter, as the gears will still lube.

Now, I'm curious if the rims will stay on the five point mounts of the wheel/rim connection? There should only be the same perimeter loading equivalent to about double or triple of the nromal tractor pulling in the field as you shift it into higher gears for more powerful tractors, and I think the rear-end could stand that.

Now help me out guys, am I missing something here? Of course, just about any tranny driven pto/rearend would do (Massey, WD-45, etc).

This is the direction I'm heading at the moment.

Anxious for input.

Frank

I seem to recall reading some years ago of injury or property damage caused by a Baker fan shedding blades. If you decide to build one, be sure the blades are capable of handling the loads caused by dissipating your 70 + horsepower.

Well, you just described a commercial variety hydraulic dynamometer like those sold by M & W. The problem with recreating that device is the high cost of the pump. For example:

If 1 horsepower = 33,000 FT-LBS/Minute, and hydraulically, it�s pressure X volume, you get:

Lbs/Sq In X Gallons/Minute = Lbs/Sq Inches X Gallons (231 Cu inches/Gallon)/Minute = Lb-Inches/minute.

12 inch-lbs = 1 foot pound, therefore divide the equation above by 12 to get ft-lbs/min.

I want to be able to test up to 100 hp, so I�ll need to handle 3,300,000 FT-LBS/minute, or 39,600,000 IN-LBS/min. Working backwards, I get, at 2000 psi, a required pump size of 85 GPM at 2000 PSI, and here�s the important thing�..at 540 RPM. I think a pump that large will be hard to come by. Remember as you drop the rpms, you need an even bigger pump, so you can�t just take one off of a junked 5020 that normally ran at engine speed of 2500 rpm without dividing it�s output by around 5. OR, you have to build a very rugged speed increasing transmission to get the pumnp upto it's speed of 2500.

Any ideas where I can find a pump that big?

That�s why we�re kicking around alternatives.

Frank

Does a pump like that mount up by the motor, and then it is belt driven? I never worked around a h-stat combine, though my compact tractor is a h-stat. Belt driven might make it eaier to configure.

You said exactly what my wife said! She said, "You mean you fixed it up, and now you're trying to intentionally wear it out?"

City girl..... .Ha!

So, we need to find a prop off of say a C-119, complete with prop governor..... Ha!

Seriously, a variable load unit would be neat, but it really makes it more complicated, doesn't it....

But if we can't find for a "Dollar-Nineteen", we'll have to use one from something newer!

hp2 = (rpm2/rpm1)^3 x hp1

What folks a whole lot sharper than me would not tackle is this: given the OD & ID of the fan blade arc and the paddle dims, what HP is required to turn the fan at, say, 300 RPM? NOBODY would approach solving the question in this manner. They just pointed me to the above equation. I have also flipped the equation around to develop a chart that says: If your SO and So WTF model tractor is 50 HP at the belt, then you should be able to crank our fan at 431 RPM. If you can't, you're a fibber, or your tractor needs tuned.

You're RPM doubled = 8x HP requirements immediately made me close down the YT window and open up my fan chart. I have it on an Excel spreadsheet where I can plug the observed fan RPM in and get the HP figure in another column. Dang if that ain't true! It varies a couple of tenths here and there, but it's as concrete as things get.

On and off for a year I kept banging on people to figure out the fan from a dimensional viewpoint. No takers. I suppose if I talked to an engineer that designed fans or propellers, that might've gotten the answer I wanted. Everyone kept quoting the fan law...the fan law...change in RPM...change in RPM...Doooh! (Homer Simpson sound). It was staring me right in the puss.

The key is having a known HP and that known HP turning the fan at the max that HP will get you. We had a guy with a Super M on the fan last summer. He got 430 RPM max. I safely assumed the Super M was factory at 46.37 max BHP because the Super M owner's stuff is 'right'. Just plug these figures in for the base point, then work the equation up or down. I DID make an assumption about the Super M, but using it as a base point squares with what I remember an Oliver 88 Diesel (54 HP) turned two years ago on the fan. What I really need to do, and I'll get to it, is put my Deering W-9 on the fan and see what the RPM is. The W-9 was belted to a real neat prony brake 1-1/2 months ago, and registered 50.0 BHP. That is for sure a known HP figure, and then I'll use the W-9 as a bench mark. Am now wondering about efficiency and % loss with a belt drive.