Official FMS 1500mm P-47D Razorback Thread

[jetfool]

Great test data. If you're like me, many ideas in my sleep will eventually transpire into a workable solution for your Cuff problem. I would guess that the Curtiss engineers went through many designs before they got it right.
Best Regards, Rex

[davegee]

Great test data. If you're like me, many ideas in my sleep will eventually transpire into a workable solution for your Cuff problem. I would guess that the Curtiss engineers went through many designs before they got it right.
Best Regards, Rex

Thanks, Rex. Whenever I have days like this, I try to think of a tour I took once of Thomas Edison's laboratory that was moved to Greenfield Village, Michigan by his good friend Henry Ford many years ago. It looks as if Edison had just stepped out for a few minutes. But as you look around there is a wooden barrel full of broken light bulbs, all failures as he searched again and again for the proper filament to make an incandescent bulb. After literally a barrel full of failures, he finally came up with a winner. It's good to remember people like Edison who kept at it until they succeeded.

Cheers

Davegee

[Grossman56]

I wonder if you couldn't rig up a 'test stand' using a spare motor/ESC and receiver placed in a solid wooden box or something similar. Seems to me that might be a be a better route than risking the airplane each time. Just a thought.
How did the prop balance work out after the cuffs were on?
I'll be heading to the field tomorrow hopefully around 8:30 depending on the wind, hopefully see you there.

Grossman56
(Dangerous Dan)

[davegee]

I wonder if you couldn't rig up a 'test stand' using a spare motor/ESC and receiver placed in a solid wooden box or something similar. Seems to me that might be a be a better route than risking the airplane each time. Just a thought.
How did the prop balance work out after the cuffs were on?
I'll be heading to the field tomorrow hopefully around 8:30 depending on the wind, hopefully see you there.

Grossman56
(Dangerous Dan)

Might be a good plan, going forward. I'll work on it. In the meantime, when I want to fly "Ole Cock" I'll just transfer the prop from one of my other jugs (Ham.Stan, prop vs. Curtiss Electric) to fly it around.

I'll try to meet you at the field tomorrow morning. Are you going to bring your Corsair? I'll bring my camera for some in-air shots, whatever you bring.

I think I'll load my Corsair as well as my Cougar.

Davegee

[Elbee]

davegee


Curtis Electric Prop Cuff P-47test2.stl

Give this a go, Dave.

Same ID as the vase mode print with twice the wall thickness (0.5mm).

I have not printed this but it should be fine.

Do not use vase mode for this as the part is already hollowed except the base.

If it were me, I'd use the same flexible adhesive and spread it all around where the cuff meets the prop.

You might have done that on the previous version, then good.

Best, LB

[davegee]

davegee


[ATTACH]n427526[/ATTACH]

Give this a go, Dave.

Same ID as the vase mode print with twice the wall thickness (0.5mm).

I have not printed this but it should be fine.

Do not use vase mode for this as the part is already hollowed except the base.

If it were me, I'd use the same flexible adhesive and spread it all around where the cuff meets the prop.

You might have done that on the previous version, then good.

Best, LB

Hi Steve: I figure we are 50% on the way to success, since two of the four cuffs stayed on! I think I'm going to start from square one since I have some extra prop blades and hubs and will add your new prop cuffs. I'll run full static tests with these and iif the stay on with that, I'll go for a couple of test flights. Regardless, the shape of even the last ones you made were great, better than I've seen before. We are close, very close, to success!

Thanks again, will post results.

BTW: Danger Dan and I did a photo shoot and he flew his second flight on his new Corsair and mine in the background. He'll post some of the pics we took. Some came out quite well, if I do say so myself. He'll probably post them sometime today.

Cheers

Davegee

[davegee]

davegee


[ATTACH]n427526[/ATTACH]

Give this a go, Dave.

Same ID as the vase mode print with twice the wall thickness (0.5mm).

I have not printed this but it should be fine.

Do not use vase mode for this as the part is already hollowed except the base.

If it were me, I'd use the same flexible adhesive and spread it all around where the cuff meets the prop.

You might have done that on the previous version, then good.

Best, LB

I just completed a static test of a new prop with the reprinted Elbee V2 improved Curtiss propeller cuffs. This time I used a lot of E6000 flexible glue and later sealed the two ends of the cuff with super glue to help keep them in place and not want to depart the airplane. They look to be on there very solid now. I ran the prop through the wringer, full power for about 30 seconds about 4 times. and then simulated rapid power changes between idle and full power and all in between as might be encountered on a flight.

So, thiis test prop (all parts unpainted until I give them the "thumbs up" after some test flights tomorrow morning) will hopefully pass with flying colors and then I'lll do more test flights with the Elbee final version Curtiss prop dome on the intended airplane "Ole Cock." For tomorrow, I'll be using my oldest surviving P-47, I Wanted Wings.

Will report back after tomorrow's test flights!

cheers

davegee

[davegee]

I just completed a static test of a new prop with the reprinted Elbee V2 improved Curtiss propeller cuffs. This time I used a lot of E6000 flexible glue and later sealed the two ends of the cuff with super glue to help keep them in place and not want to depart the airplane. They look to be on there very solid now. I ran the prop through the wringer, full power for about 30 seconds about 4 times. and then simulated rapid power changes between idle and full power and all in between as might be encountered on a flight.

So, thiis test prop (all parts unpainted until I give them the "thumbs up" after some test flights tomorrow morning) will hopefully pass with flying colors and then I'lll do more test flights with the Elbee final version Curtiss prop dome on the intended airplane "Ole Cock." For tomorrow, I'll be using my oldest surviving P-47, I Wanted Wings.

Will report back after tomorrow's test flights!

cheers

davegee

I was able to get a quick flight in today, although the weather could have been better to do it. Pretty strong crosswind and very gusty and dusty. I had a very minor prop strike on the takeoff roll that I think was caused by a crosswise large crack in the runway surface that caused the front wheels to get stuck momentarily early on the takeoff roll. I decided to take off anyway and it flew ok, although I brought it back down pretty soon to inspect the prop afterwards for possible damage. Just a few scrapes on the prop tips which was easy to sand down to smooth again.

A big difference with this prop is that I sealed the front and rear edges of the Elbee prop cuffs,with CA as well as used a lot of E6000 glue inside the rest of the cuffs to make it pretty solid. When I did a test runup prior to my flight today, I didn't get the same sound that I have been used to hearing before with my old prop cuffs. It was more like everything was humming in unison with no odd sounds or vibrations coming from gaps in the glue joints of my old cuffs that probably caused them to blow off at high rpms of the engine.

I'll continue to fly some more tomorrow with the new prop cuffs. At this point, it looks encouraging. It probably wasn't a problem with the cuffs Elbee made at all, but more probably was my glue joints that caused the problems. If things go well tomorrow, I think this problem is solved! I'll inlcude a pic at the field of the test prop (unpainted.) I am curently painting it and will test it and another prop tomorrow with these cuff improvements.

Davegee

[Grossman56]

Good news Dave!
I think I might spend some time hauling over some of that sand that they've been piling up from the gravel pit expansion on our field's west side. Maybe it will smoothen out some of those pesky cracks. I know that the rain will eventually wash it away again, but it's not like there's not enough sand sitting there.

Grossman56
(Dangerous Dan)

[Elbee]

Good news Dave!
I think I might spend some time hauling over some of that sand that they've been piling up from the gravel pit expansion on our field's west side. Maybe it will smoothen out some of those pesky cracks. I know that the rain will eventually wash it away again, but it's not like there's not enough sand sitting there.

Grossman56
(Dangerous Dan)

Mix a little mortar or concrete with that sand (30-40 %) and when it rains (lightly) it will harden into crack filler.

It's what I do around here to fill in almost every concrete crack, chip and etc.

Best, LB

[davegee]

Good news Dave!
I think I might spend some time hauling over some of that sand that they've been piling up from the gravel pit expansion on our field's west side. Maybe it will smoothen out some of those pesky cracks. I know that the rain will eventually wash it away again, but it's not like there's not enough sand sitting there.

Grossman56
(Dangerous Dan)

I don't think they'd miss a few shovelsful of that sand. I'd be up for doing that to fill in some of those GD cracks in the runway! Especially with jets, almost every takeoff is like an RAF jet taking off one of those carriers with the ramp on the end. I think they call them "jump jets." Except with this runway, you don't know exactly when or where on the takeoff roll it is going to occur. You just have to react and help it get flying speed before it crashes. What a life!

Cheers

davegee

[davegee]

Mix a little mortar or concrete with that sand (30-40 %) and when it rains (lightly) it will harden into crack filler.

It's what I do around here to fill in almost every concrete crack, chip and etc.

Best, LB

I like that idea, Elbee!👍👍👍

Davegee

[davegee]

So, the winds and rainshowers abated for a while, leaving us with gorgeous blue skies and light winds this morning. Had to take advantage of that! Today's flights I got three flights on my intended final airplane for the CE prop and dome, "Ole Cock". I have almost 50 flights on this airplane now, a lot more on the other two that I have. I made up a duplicate CE prop to try on this airplane to see how different the two of them were (they should be identical, in theory) but I wanted to see if there were any big differences between the two that I made up.

The first flight I got in carried no drop tank, a clean configuration, and flew it around the patch several times before bringing it in for a normal, routine landing. I then switched to the identical other prop and added the foam centerline drop tank. It flew about the same. Did one more flight for good measure, and called it a day.

How did they do? Both props acted as I expected them to, little to no difference between them. With the Elbee printed cuffs and my using better gluing technique as well as sealing the ends of each cuff, with CA, they were more aerodynnamic that my earlier versions, and throughout all the tests so far, they have hung in there rigidly with no damage, slippage, or anything I could find how they might have degraded any on the test flights so far.

My next tests will use the CE prop for some flights, and the stock (meaning the V3 FMS 1700mm Corsair prop) with no cuffs on it. I want to see if one is a bit "draggier" than the other, although I don't expect to see much difference.

I'll post some pics from this morning. On one photo, I placed the extra prop that was also flown this morning along with the mounted one. Both have the CE cuffs on them.

Cheers

Davegee

[Elbee]

davegee

Great lookin' pics and super-dooper mod.

Best, LB

[jetfool]

Davegee,
Fantastic photos. I think you have a real P-47 stationed on your runway that you're just teasing us with. You have really made this model realistic. Congrats.
Best Regards, Rex

[davegee]

davegee

Great lookin' pics and super-dooper mod.

Best, LB

Thanks again for your help, LB. You nailed the shape and size of the CE prop dome, and the revised printed and strengthened prop cuffs after gluing in properly work like a champ! 😁😁😁

Cheers

Davegee

[davegee]

Davegee,
Fantastic photos. I think you have a real P-47 stationed on your runway that you're just teasing us with. You have really made this model realistic. Congrats.
Best Regards, Rex

Hi Rex: if only it was a full size P-47!!! Thanks for the comments. If you want me to send you some printed V2 prop cuffs For Lucky, let me know. Also, if you want a printed Elbee prop dome I can throw one of those in, too. They print up easily and fit very well on the V3 FMS Corsair prop bases.

If you want them, I can send it to your snail mail address. Maybe PM me the address and I'll send you at least 5 of them (four plus a spare.) with the tests last week and today, I think they will work ok.

Cheers

Davegee

[f4u ausie]

I agree jetfool. Dave's run into,$$_. And has bought a real jug

[davegee]

I agree jetfool. Dave's run into,$$_. And has bought a real jug

HA! Even if I do have one, I can't afford to feed it 100 gallons/hour of 100/130 fuel to fly it!!😞Appreciate the thought, though!

[jetfool]

f4uausie,
I agree with you, Dave must have found a pile of GOLD in those mountains.

Grossman56,
Dan, You have seen these fly so you need to get one also and add all the modifications. This and the FL Corsair are definitely two of the best models on the market to modify. FMS P-47- $379

Best Regards, Rex