Building the Guillows B-25 (26.5" span, now 31") with RC and brushless motors.

[Frank v B]

Houston- we have another problem!!

Dropped the wing and landed on the spar.  It allowed the ESC to pull out.  The weakest link- the solder joint between the motor windings and the red wire.
Decided to see if I could solder the wire back.  The joint went well but then black wire pulled out.  The wire from the windings was so short that it was hard to solder.  The motor spun but it got hot.  I probably permanently shorted it out. 

Conclusion:  The missing item: the soldering skill of Greg "AMD Chip man" Hazelton. 

The photo shows the red wire separated from the motor.

The magnifying glass was very helpful and so was the fine-tip soldering iron.  Just the ability was lacking.  A white cane would have been more useful.

Will get a new motor.  Not worth the risk.

Frank

[Andy Hoffer]

Hey @Frank v B

Sorry to hear of your pre-completion hangar rash.  What a bummer!

Well, at least you can say you ended 2020 with a bang! 

See https://temac.ca/smf/index.php?topic=7745.msg52637#msg52637 for choice of masks.

Andy

[Frank v B]

Everybody on board!!!!

Just about to glue the wings to the fuse.

Notice from the nose to the back:

i) - the wires from all the electrical stuff in the cockpit.  What is showing are the ends of 2 "Y" connectors (aileron, ESC.), 2 HST plugs plus wires from the elevator and rudder servos.

ii) Next is the flat carbon main spar that extends to the outer ribs of the nacelle.

iii) next is the balsa sub-spar that slips just into the fuselage but not across the fuse.

iv) The ESC wires- both the lipo connection and the receiver wires.

V) The aileron servo wires (red, white, black)

vi) The rear dowel to hold the rear portion of the wing.  Extends through the fuselage.

Next steps- glue the wings in place with 5 minute epoxy.  Will hold it and watch it until it cures.  Have to make sure the dihedral is proper and the incidence is correct.  If it sets wrong it will be a lot of work to fix it.

.... after dinner tonight.

Frank


Notice the missing motor on the starboard wing.

[Frank v B]

- Wings glued in place with proper dihedral.
- Tail feathers glued in place.
- wing covering finished, last aileron covered and hinged permanently.

Photos of the rough assembly.  Still a lot of detailing to go (pushrods, wheels, nacelles, cowling, nose and tail cone, aileron, elevator and rudder servo hookups, etc.)

Will weigh it tomorrow when more of the stuff is in place.


Frank

Note: Holding it and looking at it with the larger wings, this plane looks like a midair collision between a B-25 (the original design), a B-29 because of the proportions and shape of the wings, and a Lancaster because of the combination of the larger wing and twin tail.  I suspect the plane will look like a twin engined Lancaster in the air.  The look will change again once the nose and tail cones and nacelles are in place.

[Andy Hoffer]

Hey @Frank v B ,

It definitely looks like a Francaster! 

Andy

[Frank v B]

Andy,




Frank

ps: Happy New Year everyone.... in 56 minutes.

[Frank v B]

10 minute accurate invasion stripes.  Original photo of the full size plane shows the stripes.

Step 1- Accurately eyeballed ( ) the photo and decided that the total pattern (white, black, white, black, white) should be 4" wide.
Step 2- cut white covering 4" wide and applied it (accurately of course).  Photo 3211
Step 3- measured black covering and cut the stripes (4/5") and applied them onto the white. Photo 3212
Step 4- stand back and admire.

Frank

[Andy Hoffer]

Houston- we have another problem!!

Dropped the wing and landed on the spar.  It allowed the ESC to pull out.  The weakest link- the solder joint between the motor windings and the red wire.
Decided to see if I could solder the wire back.  The joint went well but then black wire pulled out.  The wire from the windings was so short that it was hard to solder.  The motor spun but it got hot.  I probably permanently shorted it out. 

Conclusion:  The missing item: the soldering skill of Greg "AMD Chip man" Hazelton. 

The photo shows the red wire separated from the motor.

The magnifying glass was very helpful and so was the fine-tip soldering iron.  Just the ability was lacking.  A white cane would have been more useful.

Will get a new motor.  Not worth the risk.

Frank

[Andy Hoffer]

Houston- we have another problem!!

Dropped the wing and landed on the spar.  It allowed the ESC to pull out.  The weakest link- the solder joint between the motor windings and the red wire.
Decided to see if I could solder the wire back.  The joint went well but then black wire pulled out.  The wire from the windings was so short that it was hard to solder.  The motor spun but it got hot.  I probably permanently shorted it out. 

Conclusion:  The missing item: the soldering skill of Greg "AMD Chip man" Hazelton. 

The photo shows the red wire separated from the motor.

The magnifying glass was very helpful and so was the fine-tip soldering iron.  Just the ability was lacking.  A white cane would have been more useful.

Will get a new motor.  Not worth the risk.

Frank

Hi @Frank v B ,

Mind if I have a go at your dead E-flite 180?  Just for entertainment, and to have a memento of you to hang in my shop as reminder of shop practices to be avoided, I thought it would be fun to try teasing out one turn of the affected winding to get a strand long enough to allow proper resoldering of the motor lead. I could even balance the windings by unwinding equivalent lengths from the other two phases and resoldering their respective leads.  Of course I would checking for a short(s) elsewhere in your physics experiment. 

Cheers!

Andy

[Frank v B]

Andy,

Here's the deal on the motor... If you can fix it in 10 minutes- no.  If it takes you a month- absolutely.
Four weeks of peace for a $40 motor- absolutely priceless.

Frank

[Andy Hoffer]

Andy,

Here's the deal on the motor... If you can fix it in 10 minutes- no.  If t takes you a month- absolutely.
Four weeks of peace for a $40 motor- absolutely priceless.

Frank

Thanks @Frank v B .  I'm sure I can stretch a 5-minute job to go along with a few nice Brahms concertos, say the Piano Concerto No. 1 in D minor, Op. 15  (https://www.youtube.com/watch?v=OOlc2PAiWUU),  the Piano Concerto No 2 in B flat major, Op 83  (https://www.youtube.com/watch?v=40NsFKuskH0),  and the Violin Concerto in D major, Op. 77 (https://www.youtube.com/watch?v=7C_U7eUbVd8), for starters.  Just imagine what you could do if you listened to these while you're doing a build!!   

Andy

[Frank v B]

Now for the final assembly
- painted the cowls, nacelles and installed them permanently.  Yes, I did install the new motor first.
- assembled the landing gear.  Even spray painted the wheel rims to match.
- installed the servo arms and centred the arms.

Next on the list: canopies (nose and tail), connect the flying surfaces to the servos.

Assembled it to see what it looks like.  Cute.  It is a lot smaller than it seems in the pictures.

Frank

[Frank v B]

Total weight so far (no battery) is 10.4 oz.
Better than I thought it would be at this stage.*

F.

Someone built the same size Guillow's P-38 and it came out at 32 oz. and it flew fine!!!
He used an 1800 mah 3S battery.  Mine will use one 300-400 Mah 3S battery.

[GuyOReilly]

Looks amazing!!
These props should be black or metal grey, then it would be OUTSTANDING! 
Love to follow that build.
I am on vacation all week therefore free to attend the Maiden Flight! 

[sihinch]

Awesome build Frank. Nice job!