Brodak Thunderbird

I am going to start my winter project, a Brodak Thunderbird, in the next few weeks. I built a Brodak Ares and there were some conflicts in the prints vs instructions. If anyone can offer or share advise on the Thunderbird I would be thankful.

I already found that the plans call for a 35 to 40 motor and the instructions call for a 46 to 60 motor. I am going with a Fox 40 deluxe.

Thanks again
Dave

it is a nice plane i'll read this topic with a lot of interest :3

>I already found that the plans call for a 35 to 40 motor and
>the instructions call for a 46 to 60 motor. I am going with a
>Fox 40 deluxe.

Do you have some evidence (like lengthy previous experience) that this engine runs well in a stunt plane? I am pretty sure it would be powerful enough but I am skeptical that unless it has been proven to run properly in a stunt application, you might have problems down the road.

Brett

>
>>I already found that the plans call for a 35 to 40 motor
>and
>>the instructions call for a 46 to 60 motor. I am going
>with a
>>Fox 40 deluxe.
>
> Do you have some evidence (like lengthy previous
>experience) that this engine runs well in a stunt plane? I am
>pretty sure it would be powerful enough but I am skeptical
>that unless it has been proven to run properly in a stunt
>application, you might have problems down the road.
>
> Brett


I have a Fox 40 on the Ares and it works well. Not a lot of flight time on it but so far no issues.

I built a TB-1 from scratch, so it's probably lighter (actually much lighter) than a kit...but a McCoy 40RH has no problem keeping the lines tight on 60' lines and overheads. I had a McCoy 35RH and it did ok but the 40 with a Big Art tongue muff is much better. I'm not sure the weight trade off of a larger engine would do much better. It has a 4oz metal tank and balanced right on the numbers without adding weight. The only building advice I would give is to cut weight anywhere you can.

bp

I had the Fox .40 Deluxe and the Fox .40 compact. Got rid of them quick as niether ran smooth. The Compact ran better. Same engine no BB. Put a OS .40H in plane and it was great. OS Starts first flip and rock steady. Fox's were all over the place for needle setting. Sometimes you get lucky and they send engine out that run ok. Most need to be sent to someone to alter timing etc.

>I had the Fox .40 Deluxe and the Fox .40 compact. Got rid of
>them quick as niether ran smooth. The Compact ran better. Same
>engine no BB. Put a OS .40H in plane and it was great. OS
>Starts first flip and rock steady. Fox's were all over the
>place for needle setting. Sometimes you get lucky and they
>send engine out that run ok. Most need to be sent to someone
>to alter timing etc.

It ran good on the bench. I had a bear of a time with the Fox 40 on the Ares with the motor inverted. Its a PITA to prime the fuel lines seeing its not easy to get at the venturi. The Thunderbird is mounted upright so I hope it runs good.

Nobody has info on buliding this thing?

Thanks
Dave

My T-Bird was built from a RSM kit. Power is OS 35-S. Not the most powerful engine, but it is about right for the T-Bird. Remember that Bob Palmer did pretty well with this plane and the low-power engines of his day. Unless the Fox 40 is a real dog, it should work.

Floyd
AMA 796
SAM 188
LSF 020

Getting my Brodak T-bird ready for paint. Nothing to be concerned about, went together nicely. Pretty good wood for a kit, laser cut very well. Instructions seem to be accurate and clear. Good choice for a newer kit builder! Mine will have a Byron Barker 40 FP.

Byron is a member of my club. HE will be reworking my O.S. Max FP 40 this winter. his engines are awesome.

I never had any problem with stock Fox 40s upright. I had bb and plain bearing versions...ran them rich with 5% nitro and 20% castor. There is no difference in power between the bb and plain bearing either. Power is same as an OS FP40 or TT GP40.

>I never had any problem with stock Fox 40s upright. I had bb
>and plain bearing versions...ran them rich with 5% nitro and
>20% castor. There is no difference in power between the bb and
>plain bearing either. Power is same as an OS FP40 or TT GP40.
>

That is great to hear. I spent a few hours last night sperating and labling the balsa. Laid out all the loose wing ribs and tonight I will start on the spars.

Thanks for the help
Dave

Hi Dave. It would be much appreciated if you were to take some pics as you build and share them with us. I want to build a Thunderbird as well

>Hi Dave. It would be much appreciated if you were to take
>some pics as you build and share them with us. I want to
>build a Thunderbird as well


Will Do. I have to post some pictures of the Ares I made for my son. I made it into a Batman themed plane. He's only 7 so he wont be flying it for awhile.

We built the Brodak Thunderbird kit, and it came out a decent weight, no problems flying it with a Big Art OS .35S. We did have a problem when trimming though, the right wing tip section had drooped slightly giving it what amounted to a bank into the circle. The wing tip sections are the only area that needs to be built carefully.

Big Bear <><
Character: It's what you do when no one else is watching.