Let´s continue working on the wing...we´re going to finish sheeting the top center and also continue doing the spilers. We cut the blades to the correct size from a preshaped trailing edge....

After the top sheeting and spoilers blade cutting were done, we continued with the fuse build. As this is a electric conversion we must planning before how the propulsion elements will be, weigh and try that all will fit on the front, before the CG, and also the neccesary cut-out or bulkheads mods to our conversion.
To save weigh and space and preserve to the conversion, we swapped the servos and used digitals miniservos instead of standard size ones.
Cheking the plans and using little servos does that motor, battery and speed control will be fitted below the hatch area, on the nose..., a little tigh but they will fit.... that´s a good news.
Also we like to preserve the lines and lenght and widness of this ship, but try to keep a more streamlined fuse..., we also will change the front hatch to a simulated balsa built-up canopy...

We couldn´t resist and joined the two wing halves... Wow ĦĦĦĦ it needs some sanding and others minors stuffs, but actually this is a true Olympic II wing...
After drinking a coffe cup while take and rest a little seeing the wing we continued with the fuse build tracing the lines were bulkhead will be fitted..

Let´s continue with the fuse build... To save weigh and interior space for the electric propulsion we used digitals mini servos instead of standard size one. By this reasan we redesigned a new servo tray with 3mm. light plywood plate and pine rails on the fuse sides and below glued to the main bulkhead. Also we installed the servo arm and keepers to see were we must drill for the tail transmision tubes...

Continue with the bulkheads mods. As the wing will be screw bolt on instead of rubber bands. we added at top of F-2 a piece of 3mm. aircraft plywood to drill later for the two front dowells, corners were round to let a balsa framed canopy-hatch. A front reinforcement of good Findland 3mm. aircraft grade plywood were added to the upper half F-2 bulkhead to be support the loads...
On F-1 bulkhead we cutted a lateral passage to let route more later the motor cables. Motor will be installed cowled on a very tigh area and extreme caution it is neccesary to avoid that cables touch the motor body when running.
Firewall was made laminating two pieces of 3mm. plywood. We used the sticker incluided on the Axi motor box with bolting and vent pattern to drill the holes on the firewall for the screws and ducting fresh air into the engine...
The area of the fuse sides that cover lateraly the nose cone on the original non powered sailplane were cutted. We added 2 degrees of right hand incidence so right side fuse it is over 1´5 mm. shorter than left one. Also, another 2 down degrees were added for vertical motor incidence.

I recently completed a e-power glider and wanted to build it light as possible. When i went to select my rudder and elevator pushrods i decided to first weigh both the steel music wire (.040) and carbon fibre (.050).

The difference in weight was significant - something like 4 to 1. This allowed me to save a signicant amount of nose lead weight using the CF pushrods vs. music wire. I didn't have too much room in the nose area so there wasn't the option of a bigger battery.

thank you again for the detailed build thread, i am really enjoying it.

john s.

Originally Posted by jswain

I recently completed a e-power glider and wanted to build it light as possible. When i went to select my rudder and elevator pushrods i decided to first weigh both the steel music wire (.040) and carbon fibre (.050).

The difference in weight was significant - something like 4 to 1. This allowed me to save a signicant amount of nose lead weight using the CF pushrods vs. music wire. I didn't have too much room in the nose area so there wasn't the option of a bigger battery.

thank you again for the detailed build thread, i am really enjoying it.

john s.

Tx a lot for your kindly words John,... I´m absolutly OK with you about that mini-hint of changing metal pushrods by carbon or fiberglass... Actually, during my TF P-47 e-conversion build, ... mine came a tad tail heavy.. so I did what you say and changed some of the metal pushrods, by fiberglass-carbon kite rods and use only some of the metal as stiffners... and voila...ĦĦĦĦ CG came on the right spot...
http://www.acro3d.com/public/phpbb3/...php?f=2&t=8920

By the way, on the O2 I´m using Lazer Nyrods from Dubro.., I think, ... not sure, but maybe they´re the same incluided on the new versions from Skybench..., anyway if neccesary I may swap the little metal stiffners incluided on the pushrods bag for another from carbon...
Tx again buddy...
Manolo...

Just letting you know that I'm watching your build and am really enjoying it also. Great photo documentation! (nice lighting too ) I went with CF pushrods for the same reason that JS notes - trying to keep the weight aft as low as possible.

I'm going to start building the wings for mine today and after some confusion about how to get the first few ribs setup with the ply spar pieces -and cutting the ribs so that it all goes together as it should, I think I've got it. We shall see!

Keep the posts coming!

Cheers,

Rob
P.S. Oh yeah, John, nice Ultra MkIV!! (I still hear the cheering!)

Hi Rob, Tx a lot for your gentle words, and wish you that enjoy during the building of this fine ship; no doubt about asking any question if i may help you... and feel free to posting anything here if you wish...
Provisionallly, we installed the motor on the firewall to check any misalignament on mounting holes if necessary. Here I preffer to use allen head 3mm. screw by 8 mm. lenght and washers.
As the space near the motor is very tigh, cables goes up, later they will be covered by the framed canopy...
Also, even it is early, now is easier.. so, we drilled the servo plate for the mounting servo screws. I like to use the allen head type from Dubro, as they screw all lenght and are easy to handle. I drilled holes with 1´5 mm., after that we tapped the screw, unscrew and add a little fine ciano to harden the threads inside the wood for more security mounting...
Also on the top of the main bulkhead two 7mm. dia. holes were drilled for the front wing dowels...
When all bulkheads are finished now it is time to really frame the fuse, so we glued all the bulkheads straing to the bottom fuse as first step. For added strengh and easy position we added a 8mm. balsa triangle spar on the bottom of the bulkheads...

Let´s continue framing the fuse... We checked for one las time the fit of all the bulkheads and firewall and when everything was OK, then we glued both fuse sides. We used fine ciano on all the interior joints and alifatic yellow glue for the exterior joints, ( I preffer use if possible white or alifatic glue on all exterior joints cause later, at the sanding time is more easier and prevides a smother finish than ciano.. ). Epoxy were used to fit the firewall and some x-acto clamps were used to hold the stress of curving the fuse sides. Also I pinned the bottom and side fuses to the building board after protect the plans with Reynolds wax paper...
For just in case... I traced the final pattern of the bulkheads and firewall on a secure place for future references.., well if it is not necessary will be better...
As we used a bolt on wing, a plywood plate on the trailing edge it is neccesary to disipate the stress of the bolt-on screws, so the trailing edge of the wing will be about 7mm. tall or so on the top of the fuse. As the top sheeting fuse is 3/32 we used a scrap of trailing edge so the difference of heigh between will be more flow...

We installed provisionally the tail to check the fit on the fuse rear and alignement..., also were the time for installing the pushrods housing. As said, we used a Dubro Lazers kit. Sanding a little the exterior of the pushrods is a good idea to have a good adhesion of the glue.
We glued the pushrods housing with fine ciano every 10 cm. or so to avoid flexing and also used very few epoxy at the fuse exit. We let about 3cm. or so of the housings to protude on the exterior of the fuse sides and more latter when glue dries then we will cut it flush with the fuse sides...

Cross grain balsa 3/32 was used on the top sheeting and the scrap trailing edge to fit near the trailing edge of the wing...

We continued with the fuse build.. After top sheeting was added, we cutted the pushrods exit flush with the fuse sides.
Also, on the nose we cut a 3mm. plywood ring to matte the alum. hollowed plate of the nose cone.. As seen in the pics, we moved F-1 bulkkhead over 1cm. forward to have more room on the rear for the battery and speed controller, so a little triming of this bulkhead is neccesary cause the fuse is more slimmer near the front .

Temporally we installed the motor on the firewall cause it is neccesary for the correct alignement of the plywood ring, sanding and, as we´re going to " bashing " a little this area; ( I never liked the look of the flat radio hatch, so with permission of the good Mr. Renaud, who for sure will be flying and designing his marvelous sailplanes over these celestials heavens, we´re going to change a little this area to form a built-up canopy hatch.. ).
As the hatch goes till the plywood ring, we added two little balsa triangles pieces on the top of the firewall and sides as reinforcement. We´re going to sand a lot of the corners to have a more rounded fuse...

Hey Manolo, nothing to add really other than "looking good!"

I just wanted to let you know that someone (I'm sure there are many more) is watching and following closely

Cheers,

Rob