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Catto for another 3.75kts

H

humptybump

Well Known Member
About 18 months ago, I received a Catto propeller for my 150hp RV-8. Recognize that that particular combination is rare if not unique, Craig had to calculate the propeller.

He had imaged I would see 2750 max rpm and 4kts more speed - based on the data I had collected from my Aymar Demuthe propeller. He hit the 2750 perfectly and extensive testing (using Box Axom's test procedure) showered 3.75kts improvement. The engine CHTs dropped 15 degrees and oil temp dropped 10 degrees.

Fast forward 12 months and I had an issue with the paint on my propeller (likely because I had previously sent it back to change the paint scheme). Craig fixed the paint issue and went two steps beyond. First, he offered to change the paint color while fixing the issue. Second, when the prop came back, he had improved it.

Craig changed his nickel edge treatment slightly. When I unboxed my prop, he has added leading edge tape from the hub out to about 3/4" overlap of the nickel. As you can see in The pic, the nickel runs out and along the tip.

Craig makes an amazing propeller and he never stops trying to improve his product.

At the risk of posting prop-porn, here is a visual example of how "engineered" is the Catto propeller ...

20131216-211337.jpg

top is a Catto propeller, bottom is an Aymar Demuthe​
 
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Very Nice!!

Its funny, everyone who wanders in to peek at my plane always comments on what a great looking prop the Catto is. I've got the more standard 7/O-360 and I'm really impressed with the TAS (160-165knts) down low without wheel pants. But I can't wait to break the engine in and bring the speed and 15.2 GPH down a tad!
 
After I wear out my Catto Craig will build me a new one. Old prop will go to his museum :)
 
Those who have gone before...

Vlad said:
After I wear out my Catto Craig will build me a new one. Old prop will go to his museum :)
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Vlad,
When I was living in CA in the 90's a friend referred me to this crazy prop maker who lived in a cabin in the mountains. I had been frustrated with my wood props on my RV4 and being a fan of Theodorsen's propeller theory I called him, set up an appointment to visit.
Several weeks later I landed my RV4 on a skinny uphill 1100' one way runway nearby with an ominous wrecked Stinson parked on the approach end. A guy drove up in a jeep and got out with a big grin and introduced himself, "I'm Craig, lets go up to the shop". Craig saw my Sterba wood prop on my RV4 and grinned. We jumped in the jeep and started up the narrow fire road through the woods. His shop back then was a garage and his props were painted outside and hung in his front yard. We chatted about design, capabilities, why F16 pilots liked RV4's and what a "properly propped" Four could do performance wise. He began designing a prop for me that would be the benchmark for his new props in the future. He was already a legend in the EZ community and had designed the prop on the fastest airplane on 65HP ever, the Arnold AR-5. http://www.ar-5.com/sportav93.html

Arnold AR5 with Catto prop

Craig loaned me a prop he built for a Glasair to gather data and we slid into my RV4 with back seat removed. I had my 4 modified to carry snow skis and even larger items and Craig was impressed by the 4's utility. Once home I removed the Sterba prop, sold it and installed the Catto test prop. The first flight was anti climatic as it was way over-pitched but going downhill I could achieve VNE at very low power settings. I returned it to Craig and he began design on my new prop. Once completed I installed it on my RV4 and for the next 1000 hours it would take me on many adventures. Craig's reputation in the RV world grew and the rest as they say is history, we have been friends and "theory engineers" ever since.

If you want to know the real root of propeller design, read Theodorsen's report 924. http://naca.central.cranfield.ac.uk/reports/1949/naca-report-924.pdf
Craig is very familiar with the report and it gives you a hint of why he keeps refining his product.

For me, I smile every time I hit the starter on the X and see that prop spin...

V/R
Smokey
 
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This came FedEx,of the three I have the best experience getting box's in one piece from them. Mine came in three separate box's stapled together all three were lined with foam and the blades were warped in plastic.Well thought out and executed,I say this because it's here and it's Beautiful, like I said it's a work of art. The same goes for Saber there extension/bolts/crush plate are outstanding workmanship.These were the last pieces of the kit besides radios and mark a milestone for me after ten years of struggle.
95b8.jpg

x39zjs.jpg

142sgpj.jpg
 
smokyray said:
Vlad,
When I was living in CA in the 90's a friend referred me to this crazy prop maker who lived in a cabin in the mountains. I had been frustrated with my wood props on my RV4 and being a fan of Theodorsen's propeller theory I called him, set up an appointment to visit.
Several weeks later I landed my RV4 on a skinny uphill 1100' one way runway nearby with an ominous wrecked Stinson parked on the approach end. A guy drove up in a jeep and got out with a big grin and introduced himself, "I'm Craig, lets go up to the shop". Craig saw my Sterba wood prop on my RV4 and grinned. We jumped in the jeep and started up the narrow fire road through the woods. His shop back then was a garage and his props were painted outside and hung in his front yard. We chatted about design, capabilities, why F16 pilots liked RV4's and what a "properly propped" Four could do performance wise. He began designing a prop for me that would be the benchmark for his new props in the future. He was already a legend in the EZ community and had designed the prop on the fastest airplane on 65HP ever, the Arnold AR-5. http://www.ar-5.com/sportav93.html

Arnold AR5 with Catto prop

Craig loaned me a prop he built for a Glasair to gather data and we slid into my RV4 with back seat removed. I had my 4 modified to carry snow skis and even larger items and Craig was impressed by the 4's utility. Once home I removed the Sterba prop, sold it and installed the Catto test prop. The first flight was anti climatic as it was way over-pitched but going downhill I could achieve VNE at very low power settings. I returned it to Craig and he began design on my new prop. Once completed I installed it on my RV4 and for the next 1000 hours it would take me on many adventures. Craig's reputation in the RV world grew and the rest as they say is history, we have been friends and "theory engineers" ever since.

If you want to know the real root of propeller design, read Theodorsen's report 924. http://naca.central.cranfield.ac.uk/reports/1949/naca-report-924.pdf
Craig is very familiar with the report and it gives you a hint of why he keeps refining his product.

For me, I smile every time I hit the starter on the X and see that prop spin...

V/R
Smokey
Click to expand...



Great story Smokey interesting reference thanks. Now I know why you are testing many of his props. Real friendship is a big thing in this world.

I love my old style prop. There is a bit of paint erosion on the leading edges and at the back of blades but for 1K hours there should be some I guess. I've been to some funny places with tons of loose particles on "runways" and prop is still holding great. I thought of putting leading edge protector but after communicating with Graig decided against it. Metal protectors couldn't be retrofitted on old style blades.


 
crabandy said:
Yup the packaging is a work of art too, but the FedEx driver didn't seem too appreciate art too much!
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The ends were a little beat up,the end caps have a good 1 1/2"-2" of Styrofoam packed in them. The FedEx guy will pull in the drive and place the box by the door, The UPS driver stops unbuckles and hustles out with the package drops it by the door and runs back before the metronome has hit 6 beats and is on his way. The mail man slows down just enough to hit the lawn as he chucks the box out Frisbee style if it says fragile he throws it like a football.When I sent my crank to Tulsa and asked the best way to ship,I was asked "Would you trust the government with your crank?" I sprong for FedEx both ways.
I don't want to get off post,shipping is an art into it self.I still want to know when Vlad thinks his current prop has had enough?
RHill
 
Looks just like mine. Cant wait to fly behind it. Should be bolting it on in the foreseeable future anyway...

2uf8uvd.jpg


2cf641v.jpg


15gdp0.jpg


2e2owtl.jpg
 
It's interesting to look at the Catto prop labels. They all appear a little different and give a hint into how specific Craig is about each propeller.
 
humptybump said:
It's interesting to look at the Catto prop labels. They all appear a little different and give a hint into how specific Craig is about each propeller.
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The Catto system is unique,my engine is a stock compression 8.5:1, 0-360 with two P mag's.I'm told Fuel injection or Carburetor are not a factor, horsepower and compression are. I don't think the nose wheel factors in but frontal area might.My invoice has top speed target RPM-205mph@2750RPM. Would it be possible to post a label Photo in this thread? It would be informative to see the changes in configuration.
RHill
 
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Read the label...

rhill said:
The Catto system is unique,my engine is a stock compression 8.5:1, 0-360 with two P mag's.I'm told Fuel injection or Carburetor are not a factor, horsepower and compression are. I don't think the nose wheel factors in but frontal area might.My invoice has top speed target RPM-205mph@2750RPM. Would it be possible to post a label Photo in this thread? It would be informative to see the changes in configuration.
RHill
Click to expand...

RH,
The label goes back to the beginning. Craig showed me his computer program for blade design back in the 90's. Each prop was unique for it's application therefore he labeled the prop for the application, as pictured on page one of this thread.. Over time he has developed programs for nearly every aircraft out there including the props he made for the USAF Predator drones...

When I sold my original Catto (his first RV prop) to a RV4 guy in OH, I told him it was matched to my RV4 and, "your mileage may vary". It gave him good performance but the mantra is set, Craig has meticulous attention to detail.

My favorite Catto story was from a Vari-EZ guy. He was returning to CA from OSH. Somewhere over the Rockies he felt a "thunk" in the airframe but everything seemed normal. He continued home to CA. After landing while putting the EZ away he noticed one of his exhaust stacks missing and a large chunk knocked out of one of the blades (3 blade) The stack had fell off inflight and gone through the prop! Craig basically told him it was a minor repair and he could send it back or self-repair. :)
V/R
Smokey


My 4th Catto prop, now owned by a RV9 builder (MM). Numero Cinco now resides out front...
 
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I'm still early in my flying/testing as well as breaking in the engine but I've been consistently getting over 160 knts TAS on my o-360 Rv7 and Catto 3 blade without wheel pants or gear leg fairings. On a gas run the other day down low I was getting 167-168 knts TAS, I can't wait to put the fairings on it!
 
Catto 3 blades

Yes they are a work of art for sure, wanted to put mine on the living room wall but my wife didn't appreciate art as much as I did..

I just sold my original 3 bladded Catto prop and have a new Carbon Fiber with the Nickel leading edge being built as we speak and I just can't wait to try it out..

If it is half as smooth as my old one, I'll be a happy camper and if I gain a little bit of speed in the process..so much the better..

Bruno
[email protected]
 
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