Tamiya 1/32 Corsair "Birdcage"

[Bstarr3]

I think I’m going to work on the resin tire. We’ll see how it goes…

[Bstarr3]

While on the topic of aftermarket...

 

I went ahead and purchased the Brassin cowling.  It certainly would show better with an open engine, but the extra detail on the cowling flaps made it worthwhile to me.  Look at the difference from the kit part!

 

 

 

I know that this part is designed specifically for the Tamiya kit, but is anyone aware of any fit issues that I need to be on the lookout for with using this part?  

[monthebiff]

Very nice start to your build and lovely looking cockpit. The Brassin cowl set looks so nice but beware

 

Have a look at my build log , page 4 or 5 to see the issues I had with my set. Ended up selling it to someone on ebay in the end.

 

Regards. Andy 

[Bstarr3]

1 hour ago, monthebiff said:

Very nice start to your build and lovely looking cockpit. The Brassin cowl set looks so nice but beware

 

Have a look at my build log , page 4 or 5 to see the issues I had with my set. Ended up selling it to someone on ebay in the end.

 

Regards. Andy 

Wow what a bummer! Thanks for the heads up. 

[Dpgsbody55]

6 hours ago, monthebiff said:

Very nice start to your build and lovely looking cockpit. The Brassin cowl set looks so nice but beware

 

Have a look at my build log , page 4 or 5 to see the issues I had with my set. Ended up selling it to someone on ebay in the end.

 

Regards. Andy 

 

Good to know.  I've got an F4U-1a in my stash, so I won't be tempted to embellish mine with this "upgrade".

 

I've been enjoying your build so far.  Your cockpit looks great. 

 

 

Cheers,

Michael

[Bstarr3]

And now for something completely different…

 

As I have alluded, I plan this build as an in-flight Corsair. And what is an in flight plane without a real spinning propeller?

 

I bought some micro 3v DC motors (5 for $8 on Amazon), which happen to fit perfectly inside the gear reduction housing, with just a tiny bit of plastic surgery…

 

 

 

 

 

Assembling it in this way gave me a perfectly coaxial motor shaft (I know this isn't coaxial - I adjusted it after reviewing these photos.)

 

but I had to figure how to make sure the propeller spindle was coaxial to the motor shaft. I drilled it out, filled it with Milliput

 

 

Then I assembled everything, allowing the motor shaft to make an impression in the putty. 
 

 

After completing this clever little bit of engineering and construction, and feeling quite proud of myself, I was struck by the concern that this tiny little motor wouldn’t make enough torque to spin the prop, and I couldn’t wait for the Milliput to dry, so I rigged up a test of concept. 

Edited May 26, 2023 by Bstarr3

[MikeMaben]

 

                            ...aaand..... ?

[Bstarr3]

7 hours ago, MikeMaben said:

 

                            ...aaand..... ?

Sorry, I realize I kind of left everybody hanging there.  I was trying to figure out how to post video.  I uploaded a short clip to YouTube - let's see how this works...

 

 

Edited May 26, 2023 by Bstarr3

[Bstarr3]

Tonight’s update from the bench:

 

Sadly, it appears that my proof of concept test was not rigorous enough. Although it spins the prop just fine, it seems my motor, in spite of all my efforts, is slightly off center.

 

 If I put the whole assembly together - motor, spindle, inside the gear reduction housing - nothing happens. If I remove the gear reduction housing, the spindle spins with the motor, but has a slight wobble on its axis, I’d estimate a half a millimeter to either side. Obviously this is keeping it from spinning freely inside the gear reduction housing. 
 

So, I ask the many professional engineers on this site: how would you tackle this problem? As I see it, I have to 1) ensure the motor is perfectly perpendicular to its baseplate, and 2) center the spindle exactly on the centered and perpendicular shaft of the motor. I’d appreciate any suggestions. 
 

 

[MikeMaben]

I'm not making this up, the first 1/32 kit I built was Revell's 109F . I rigged up an electric motor in the engine compartment

and a toggle switch right behind it with wires that lead to the battery in the fuselage. There was no way I could line up

the motor with the prop shaft so I ran a piece of flex tube from the motor to the prop shaft and it worked. This was in 1967

and I was 15. So my suggestion would be to find some rubber like tubing, like some heat shrink stuff and mount the motor

close but not too close to the prop and heat shrink the tubing to the prop shaft and the motor shaft. Don't know it this all

makes sense but you could mount the motor anywhare behind the kit engine and run the frlex tube from there.

[chrish]

8 hours ago, MikeMaben said:

I'm not making this up, the first 1/32 kit I built was Revell's 109F . I rigged up an electric motor in the engine compartment

and a toggle switch right behind it with wires that lead to the battery in the fuselage. There was no way I could line up

the motor with the prop shaft so I ran a piece of flex tube from the motor to the prop shaft and it worked. This was in 1967

and I was 15. So my suggestion would be to find some rubber like tubing, like some heat shrink stuff and mount the motor

close but not too close to the prop and heat shrink the tubing to the prop shaft and the motor shaft. Don't know it this all

makes sense but you could mount the motor anywhare behind the kit engine and run the frlex tube from there.

Genius….Wiley  coyote!

another thought (my method) may be to get hold of a few pieces of aluminium or brass tube that can be telescoped into each other from the O.D. you need to the I.D. you need. You may need to oversize the piece the largest tube fits into, or sand down the largest tube….if you get my meaning.

 

[Bstarr3]

23 hours ago, MikeMaben said:

I'm not making this up, the first 1/32 kit I built was Revell's 109F . I rigged up an electric motor in the engine compartment

and a toggle switch right behind it with wires that lead to the battery in the fuselage. There was no way I could line up

the motor with the prop shaft so I ran a piece of flex tube from the motor to the prop shaft and it worked. This was in 1967

and I was 15. So my suggestion would be to find some rubber like tubing, like some heat shrink stuff and mount the motor

close but not too close to the prop and heat shrink the tubing to the prop shaft and the motor shaft. Don't know it this all

makes sense but you could mount the motor anywhare behind the kit engine and run the frlex tube from there.

Thanks for the idea. Sadly, I think with the way I’ve already modified the kit part, I’m pretty well committed to a rigid connection, because the prop spindle no longer has anything solid to keep it in place against the front of the gear reduction housing, other than the motor shaft. 

 

 

[Bstarr3]

14 hours ago, chrish said:

Genius….Wiley  coyote!

another thought (my method) may be to get hold of a few pieces of aluminium or brass tube that can be telescoped into each other from the O.D. you need to the I.D. you need. You may need to oversize the piece the largest tube fits into, or sand down the largest tube….if you get my meaning.

 

Telescoping brass rod is an idea. I’ll have to look at how I could rig that with a short distance.  Thanks for the suggestion!

[Tec182]

One silly thought that occurs is, it may be a balance issue. You might try applying a small amount of weight to one blade at a time and retesting. If that doesn’t dampen the oscillation, try two blades at a time. When we rebuild 1/1 props we always check the assembly balance and rebalance (if rebalancing is required and it usually is) before remounting. If that doesn’t have any effect, it may be alignment or a combination of both. 

Edited May 28, 2023 by Tec182

[Bstarr3]

8 hours ago, Tec182 said:

One silly thought that occurs is, it may be a balance issue. You might try applying a small amount of weight to one blade at a time and retesting. If that doesn’t dampen the oscillation, try two blades at a time. When we rebuild 1/1 props we always check the assembly balance and rebalance (if rebalancing is required and it usually is) before remounting. If that doesn’t have any effect, it may be alignment or a combination of both. 

Thank you for this insight. I knew I’d get some engineer answers that I hadn’t even thought of. I assume the weight would be most effective at the tips of the propeller?