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Teltech BD-5D E-Pusher

Last updated March 2 2001

 

This model is made in the Czech Republic and comes with a Gel Coated fuse and a foam
sheeted wing.

Cockpit Component Placement
Mid fuse placement of landing gear brace
and fuse stiffener

 

Rubber bands as shown for the battery and the canopy plus the steering rod.
Steering rod is made from scrap including plastic sleeving.

 

Notes:

 

 

Note Left thrust and up thrust
Side view of tail section

 

When you have proceeded to the tail section. Note that the RUDDER pushrod has been forced
to the left side of the vertical stab. This is required to provide correct operation of the front when and the rudder.

Horizontal and vertical stab. - Do not mount motor mount until this step.

You need to CA the vertical stab onto the fuse, Therefore you need to SAND the part where the stab is
going to be glued.. sand away the Gel coat and expose the epoxy and the fiberglass.. Apply CA + KICKER and
the glue permanently with epoxy mixed with glass powder or cotton.

For the horizontal stab, slice into the fuse with a DREMEL CUTING DISC.. Along the moulded lines.
Hand Sand with a FILE... Remove the plastic covering on the stab and glue with CA + Kicker.. later
you use epoxy and apply it onto the inside using the motor hole and a long stick.

** NOTE THAT DUE TO POOR MOULDING ** The mould line that looks like it is suppose to be in the center of the fuse is ACTUALLY SKEWED TO ONE SIDE. I Glued the vertical stab onto this line and found that it was off by 3 MM! So I made a mistake. Anyway as long as the vertical stab is vertical , the model is OK.

Motor Mount :

You need some Left thrust as said in the model instructions, so just lightly CA a prop with its prop adaptor to the ply motor mount
and apply CA kicker, Hold the prop by the prop adaptor and check your upthrust and your left thrust according to the
angle as specified . Grip the fuse tightly, apply CA to the sides of the motor mount and apply CA Kicker.

Check alignment again and permanently seal the motor mount using Epoxy . In this case Epoxy is easier to work
with then goop and since goop is flexible you don't want it here.

To have Left thrust as a pusher means that when the prop is powered, it pushes the tail toward the LEFT causing
the model to go to the right.

The Blue lines mark the CG range
The holes are DRILLED along a hidden Channel

Notes on drilling the fuse holes for the wing.

There is a HIDDEN channel above the servo mount that has been cut into the foam in the factory.. you need
to route a servo wire along this hole.. This is done by using a small plastic Tube somewhat like the inner sleeving
for the control rods seen on the aileron controls into the hole and then pulling it across..

You CA one end of the servo wire to the sleeving and push this through the factory routed hole and out
through the holes you drilled..

MAKE SURE YOU DON'T mess up and drill these 2 holes outside of the fuse or on the mating portion
of the fuse and wing.. Mark them carefully and CHECK AGAIN before drilling.

Power system

The model was powered by a Kyosho AP36L Special on 7 Cells
direct drive on a Graupner 8x6 Prop. Current draw was 36 Amps
model weighed in at 1650 Grams. Cut the necessary breathing holes
now..

I recommend Astro 035 lightened from Kirk Massey as a replacement..
You can use air intakes to cover up the ugly holes or ask Kirk to
shorten the brush holders for you...

 

Cut breathing holes in the tail
This is the outlet which is placed near the head of the motor
The Air scoop is shown placed in front of the brush holders. Note that I used a servo arm cover as an air scoop , behind this cover are drilled holes from big to small as it tapers near the back of the cover. use CA and kicker to attach the air scoop.

DECALS

Put the model on one side and repeat instructions for the other side

Flying

The CG was balanced on the average of 55mm to 70mm as recommened , that is 60mm.
25 Grams was added to the head to make sure it would behave and be head heavy
for the maiden flight.

Maiden flight was carried out on a slope.. The model was tossed very hard onto the
oncoming wind of 3 MPH, my friend powered on but the power was say 60% out
of 100% we desired as measured by Gut feel.

After one fliight we landed and removed all the weight, so the published CG range
was validated... Next we went for the second flight and we noted that during
turns, the nose dropped rapidly even though we were turning onto slope wind...

When it hit a windy patch on the slope, the model would climb very easily..
the model is NOT a old-timer floater for sure, however it will glide very very
well.. Stall is forward with no tip stall noticeable...

The model is now back on the bench and we will install an Astro 035 as direct drive.
with the Kyosho AP- 36L special, response to throttle was a little delayed..
with a more powerful motor like the 035 or 05, response would be proportional
to throttle control..

Also note that with the Kyosho Motor, It will NEVER ROG safely. I believe only with
the Astro 035 and 8 Cells will this model ROG safetly and fly well.

My assessment is that this model will fly well on a flat flying field but is crummy on
the slope even while it is powered because it tends to lift too much when wind
is encountered.. On a flat ground, all you need to do is to push elevator down to
compensate if you are landing.. on the slope you may need to turn for another
attempt lest you crash in to a tree on the hilltop or something..

Watch the movie : 304 K Windows Media
See http://www.microsoft.com/windowsmedia

 

 

General Comments

This is NOT a beginner's model for construction and for flying.. Throws are sensitive and
should be reduced approximately 60% from the default throw on the radio.

The manual is very very poor so you need to be an experienced modeller
to figure everything out..

 

Good things

  1. OK to fly (not easy to fly) - Requires experienced modeller
  2. Easy to recover from too much command input
  3. Lifts easily

Bad things

  1. Very poor manual
  2. Gel coat pops off here and there
  3. Poor centerline on mould - requires massive sanding and re-spray painting to cover up
  4. Not enough parts given, must manufacture some yourself - wood blocks for stiffening
    control lines
  5. No vertical slot for vertical stab, makes building annoying since this model was touted as
    being designed on a cad system.. they could have added a slot for the vertical stab..
    as such the vertical stab rests on a pool of CA and epoxy, quite weak.
  6. Wing Servos are poorly placed.. They are placed in two holes and the servos are
    inserted vertically, so if you remove the landing gear for slope flying with power the
    wings will get ripped off by sand and grass as the control rods are below...
    I recommend that the experienced modeller route the servo shape with dremel router
    and have the servo lie by its side, then install the control rods and have a plastic servo
    cover to guide the dirt and sand past the servo control mechanism so there is no
    snagging. If you want to fly on flat ground, then leave this as is....... it is fine.
  7. The manual claims that the most difficult of part of the model was assembling the front landing
    gear ..this is untrue, assembling the canopy took two days to carefully paint and apply decals
    to the inside .. lots of work masking and airbrushing. Also Alignment of the wings was not
    advised.. This is bad because mistakes can be made so the model can become un-airworthy..

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