Very nice Alan.  Electric just keeps getting better and better and better.........

Yea, me too. Are you also going to come up with a 3 blade CF spinner to go with them?   

Hehe. Man, you are so easy.   

Hello Joe

Regarding the 40VF.  I believe our narrow blade tractor prop would work well with the VF, however you would need to re-pitch to around 4", vs. the 5" - 5.5" we provide.

Randy,
Half of the final mould for the narrow blade tractor prop was poured yesterday.  I've got it prepped and mounted waiting for me to get my epoxy mixed.  After adding the aluminum to the resin I usually let it sit for a day for those nasty little bubbles to come to the surface.  That mould should be ready for lay-up in about 3-4 days.  We're doing some testing on the narrow blade pusher this weekend and if the mods work as expected I'll start the final mould for that one on Sunday or Monday.  I then have to so some more mods on the wide blade tractor and test it.  Last will be the wide blade pusher which is under construction.
Alan

Well I said to watch this space so here is an update.  The first prop is ready.  I finished the final mould the other day and we laid up the first prop yesterday.  I prepped it this morning and checked all the specs.  It weighs 29g which is just barely over an ounce.  This is the 11 X 5.5 tractor that we refer to as the "Red" prop.  This prop is very similar to the one used by Mr. Walker and Mr. Burger.
We are still testing the narrow blade pusher.  While on that note, Chris and I got busy in the last few days and made some new pitch gauges for pusher props.  I had constructed a gauge for pusher props a few years ago to do some checking of APC props.  Our new ones are very similar to the old Prather gauges from years back.  I might make some more if there is any interest for serious electric flyers.  They won't be cheap and I will probably only make them during a full moon.  Let me know if there is any interest.
Alan 

Hi Alan, I´m interested in the pitch gauge and props!

Rodrigo Mansano
Brazil

after lovingly fondling a few of these, they appear to be well made,, I am on the list for several,, ( when I have something to mount them on that is!)

I'll also be anxious to see a few of these.

One sees them at stunt contests, Randy.  You should attend a stunt contest someday.  They're fun.

One sees them at stunt contests, Randy.  You should attend a stunt contest someday.  They're fun.

well played Howard,, well played

Well Golden State was a good proving ground for the new props.  With 5 electric ships in the top 8 in Expert class and 4 of those using the new props I can honestly say they are competitive at a pretty high level.  Howard Rush in 4th, Chris Cox in 6th, Jim Aron 7th and myself in 8th was a pretty good showing considering the class of the field.
The "Green" prop ( 11 X 5.5 pusher), the "Red" prop ( 11 X 5.5 tractor) and the "Blue" prop ( 11 X 5.5 wide tractor) are in production.  The new "Purple" prop
(12 X 5.5 pusher) should be ready in about 2-3 weeks as the "master" prop is close to completion.

Based on your showing at GSSC Howard (ahead of me), I'm thinking I want that prop back! Your corners looked mighty fine with the new prop.

Price?

I paid $50us for mine.

and it also well fits my spinned ... not perfectly, but fits ... now just waiting for flyable weather :- ))

I would bet that it wouldn't be hard to make both LH and RH pitch gauges...or one gauge that will do both, for that matter. Not sure if the market is saturated with RH (Prather) gauges or not, but every now & then, somebody posts that they want one.

One thing that Joe posted, about the launch rpm being similar...gotta remember that the electric stays at "launch" rpm in flight, while IC engines don't. I'd like to know how much my .46VF unloads in flight, and even more curious about the r's when the boost kicks in as the uniflow tube is uncovered. It honks! Not a subtle indication to prepare for the glide portion of the flight.  Steve

Measuring the face of the prop like that won't give you the true pitch if you have any Phillips entry.

"True pitch" has no aerodynamic significance.  It's just something you can measure.  We use it to give new props a known-good pitch distribution, to keep existing props in adjustment, or to establish a standard for props we decide we like.  It's particularly easy to measure props that are concave on the back and have two points on which you can rest the measuring doodad.  If you want to know more about the prop's aerodynamic characteristics, it's easy to get the angle from the easily measured plane to the chord line of the airfoil.  Igor knows how to do that if he decides he wants do further calculations.   

Measuring the face of the prop like that won't give you the true pitch if you have any Phillips entry.

MM

I do not know if it was reaction to my pitch gauge, but it work just like mechanic gauge. So no difference. But it allows templeats usefull to measure chord line (unlike mechanic gauge)

Regarding that Phillips entry - every asymetric airfoil on prop blade will make some change of true pitch, not only Phillips entry. That difference comes from 0 lift AoA of used airfoil. Knowing that angle, we can correct pitch, my gauge has input value for that offset, so it can easily handle this problem, mechanic gauge can be corrected by anglular prop shimming :- ))

However our airplanes has some drag and prop must make some permanent thrust, so measuring lower side gives very good overview about prop and what it will do in air.

Hey Alan, I'm definitely in need of a pusher pitch guage, how do I go about getting one?  Would be about one month.

Update of new "purple" 12" pusher prop 

It appears my  "mould guy" got a little too eager to see the finished product and popped the freshly moulded master apart before the casting epoxy had a chance to fully cure.  He managed to save the 12" master prop, but put production behind by at least another week.  The added cost of pouring a new mould will be deducted from his pay cheque at the end of the month!

The Quality Control Department will be watching Mister Resinger a little more closely in the future. It's difficult to find good help these days   

Alan!
Wait till I tell Brian Eather what you did!!!! 

Watch it Russell.  I think I remember who's first on the list for the 12" pusher.  Besides, Brian knows my incompetence well,  I was just trying to get the mould done so I could take a break from making them.  I sent a couple of props down to Brian earlier this week.
Alan

Sorry Russell, if you tell Brian, that will be Alan's problem.  Inventory Control (aka Dragon Lady) would never permit a propeller leave the factory that was not properly documented.  Tell you what though, we will sell you the 12" prop's at the old price, before the anticipated price increase. 

As indicated by Alan, we did indeed make our way out to the flying field to test the new (purple) 12" pusher.

Weather during the testing was cool @ 46F and light wind, but quite choppy.  Neither Alan or I have flown since getting home from the Golden State Stunt Championships, so we figured we should first fly the green 11 x5.5 pusher for a base line.  Despite my rather rusty flying, the prop performed well, just as I remembered it.  RPM was 10,304 giving a lap time of 5.3 seconds.  Next we installed the purple 12 x 5.5 (more like 5.75 according to Alan). We anticipated the airplane would be quicker due to the added area, and we were right, 4.8 second laps (no change in RPM). Luckily we had set the air time for only 1:30.  We stepped the RPM down to around 9550 RPM and the next flight yielded a 5.1 second lap. Next setting was 9340 giving a 5.3 second lap.  Perfect. I did a vertical eight, hourglass and overhead eight in the 1:30 time frame, and liked what I saw/felt!  Time to fly a full 5:30 flight!

Did I mention above it was cool?  Well, with the wind coming on a little stronger, it was now feeling fricking cold!  Anyhow, we reset the timer to 5:30 and launched. Take-off tracked great from the time it left Alan's hand.  Still a steady 5.3 lap (why wouldn't it be, it is electric after all). Wing over felt strong with good corner.  The loops were round with very little correction, and no wind up due to the wind that was stronger and choppy than before.  Inverted flight was solid, and other than some altitude variation due to changing wind, the airplane felt very stable inverted. Corners in the squares were very hard with a clean exit, very similar to the 11" props. My first hint that this may now be my new favourite prop was the square eight.  The last outside corner where the 11" prop seems to be loosing a little poop was now very strong.  Seems the larger diameter was providing the added thrust my slightly obese (64 ounces) Crossfire needed!  The vertical eight felt strong throughout, and the third corner of the hourglass was solid, despite the wind.  I purposely flew my overhead eight loops on the small side just to see if it would hang up there - no problem!  Finally the four leaf clover, and the first loop that can sometimes feel a little loose, felt absolutely fine.  In fact, all four loops in the clover felt the same in tension and controllability. 

I was really pleased with the prop and although cold out, I had one more charged battery left and figured better to fly than go home with a charged battery.  Happy to report the prop performed equally well on the second flight! Even though I felt I was going to freeze to death, I was really having fun.

The next test was the one Both Alan and I were a little worried about, and that was how much current the new propeller required vs. the smaller 11" prop. I charged the first pack (Thunder Power 5s 25C 2700) which we used for the 11" prop.  The pack only took 1989 mah, which I found a little surprising due to the cold. I expected more.  Pretty darn good.  Next up was the pack we flew the full 5:30 on the 12" prop. Wow, this was surprising, it took only 2152 mah, which is acceptable for a 2700 battery pack.  Too be sure, I charged the last battery, and it took 2169 mah.  Wonderful!  Our fears of needing to fly a bigger/heavier pack was unwarranted.  Current demands should be less when weather warms up!

So, I am happy to report Alan and I now have four very nice props available.  Two tractors and two pushers.  They all work great, although I personally prefer the pushers for the electric set-ups.  I suspect t the 12" will be more popular for those flying more stout (read "heavy") airplanes, as it provides a little more thrust when loaded than the 11".  As mentioned in a post somewhere above, the 12" will also permit a little experimentation with diameter than the 11".

The 12" purple is my favourite for the time being!

Time to go downstairs a mold another prop!

Ah the life of the lowly peon.  We get no respect.  I think it was mostly a senior moment.  I didn't take into consideration the fact that with the colder temps, the shop temp has dropped a bit.  I was really afraid that I wasn't going to be able to save the master which would have really set things back.  Got the trusty mallet and a couple of good chisels and was able to chip out all the hardened epoxy matrix that broke away from the male half of the mould and stayed in the female half.  Only had a couple of minor dings in the back of the prop which a little epoxy filled.  The master is now refinished and will be polished and waxed in the morning so that I can prepare to remould it.
Now that my pay in going to get docked I think I'll demand at least half pay for the month.  Chris tell the Dragon Lady to issue me a check for $5 at the end of the month or I may go on strike.

Don't you use a low heat during the cure process? Maybe a heat lamp with temp control.
We use a heater blanket with temp. monitors along with vacuum bagging when we do composite repairs to flight controls and other surfaces at my place of employment (Major Airline).

I don't think that pouring a mould and doing composite surface repairs are the same thing.  Heat is a big no-no when pouring moulds.  Due to the mass of epoxy matrix used, heating needs to be kept to a minimum until the resin if fully set.  After 48 hours of curing at room temperature, the mould is then post cured for about 8 hours at elevated temperatures.  I should have stated that due to the reduced temp in my shop the resin hadn't cured sufficiently before I opened the mould to remove the master prop and then post cured the mould in our oven. 

That makes sense, since your dealing with a thicker part it must cure evenly. I guessing the post cure is for insurance.

You are making me blush Shawn!  Thanks for the kind words.  Hope the prop's do you proud.

Ps: Alan is not nearly as nice as you make him out to be. 

Congrats to both of you ,you hard work on a great prop. And Joe for his great flying.👏 🎉 ✈️

Used the 11x5.5 pusher on my new plane and all I can say is WOW!  This is one great prop!  Need to get a few more.