Ultra Bandit Build

Starting a new build or conversion? Post your information, findings and pictures here.

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Geoff White
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Ultra Bandit Build

Postby Geoff White » Fri Jun 29, 2007 6:14 pm

I am putting a Ultra Bandit together for a friend(no prizes for guessing once you see the photos) and I thought some of you might be interested in seeing whats involved.

It will be powered by a AMT Netherlands Olympus HP. The radio will consist of a mixture of 8511 and 8711's and the receiver will be a weatronics.

Geoff.
Last edited by Geoff White on Fri Jun 29, 2007 8:12 pm, edited 1 time in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 6:18 pm

So lets get started.

The first thing we have to do is to fit the front former that the front flex plates mount onto. I cyno'd it in place and then reinforced with hysol.
Image

You can also see the nosewheel steering arrangement that is used in the UB.

Next step is to add the nose wheeldoors.

The front door is simply hinged by a single plastic dubro hinge at the front.
There is no air ram on this door and it relies on air pressure to keep it shut. The spring is purely to keep the door shut when the model is on the bench.
The door is opened by the noseleg strut pushing against the wooden block that I hysol'd onto the door. This is the same system as used by both the Kingcat and the new BARF.

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The rear door is hinged using 3 dubro hinges. The individual pines were removed out of the hinges and were replaced with a single piece of piano wire. This enables the door to be removed easily if necessary.


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The only slight issue at the moment is the front door will not close completely because the wooden wedge is hitting the retract. It will have to be ground off using a dremel.

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Next came the fitting of the air ram to operate the door. It is screwed onto a nice CF bracket that comes pre supplied. The fixing on the door is also a nice piece of CF that has to be tapped for 2-56 bolt to attach it to the air ram.


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The final part of the noseleg unit is to simply cyno together a bracket together to mount the NW steering servo. Using the pushrod as a template the bracket is hysol'd onto the left hand side of the fuselage.

Image
Last edited by Geoff White on Fri Jun 29, 2007 8:22 pm, edited 4 times in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 6:20 pm

Next I moved onto the intakes.
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These are joined together and then reinforced by adding a round wooden former.

They are held in the fuz by two 4-40 screws as shown below.

Image
Last edited by Geoff White on Fri Jun 29, 2007 8:17 pm, edited 1 time in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 6:48 pm

Next comes a really important part of the build.

The two parts of the fuselage are joined using 4 steel pins that are factory installed. I was very happy to see that they fitted perfect.

They come with just a former at the front and back holding them in place which means they need reinforcing.

To do this, the first part is to create some balsa blocking pieces that fill the space between the pins and the fueslage. These are then glued into the space with plenty of hysol(not forgetting to roughen up the surface first). Then a self tapping screw is simply screwed through the hole in the pin and into the balsa. This screw is purely there to act as a anti rotation device.

Image

As you can see I have roughened the surface of the fuselage thoroughly.

Now I think I am right in saying in early UB kits that was all the reinforcing that was recommended. However in this kit BVM say to carry on and epoxy a piece of glasscloth over the whole structure to make it bullet proof.

Following instructions I mixed some epoxy resin and added milled fibre to increase the viscosity. I then added the cloth making sure it as well wetted out and had no voids.

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Just for interests sake Here is a photo of the metal bracket that receives the pin. This was factory fitted.

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OOps just remembered!

Dont forget to add some flats onto the steel pins so that they can't slip and lead to a dramtic change in trim.

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To mark the place to put the flats on the pins I placed the two halves together, tighten down the bolts. loosen the bolts and remove the fuselage and you will be left with a nice mark when the bolts tightened down onto the pins. This is a standard technique that I guess you all knew about:D
Last edited by Geoff White on Fri Jun 29, 2007 10:25 pm, edited 2 times in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 6:58 pm

I turned my attention to the rear part of the fuz, in particular the tailplane and fin mounts.

The come factory fitted and again were perfect. The mounts are screwed to a CF former with 4 4-40 bolts. However I also received an addendum from BVM saying that I should add a fillet of aeropoxy around the edge of the bracket. This is because over many flights the prototypes brackets were moving slightly.
Image

In the same manner they also said to reinforce the fin mount.

Image

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 7:03 pm

Next comes some fairings around the rear of the front fuselage

These fairings cover the access hole for the bolt that holds the fuselage pins.

Image

the fairings are held in place with a 4-40 bolt.

Image

And you get to the bolt to tighten or loosen by a small access hole just big enough for a ball driver.
Last edited by Geoff White on Fri Jun 29, 2007 9:03 pm, edited 1 time in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 7:10 pm

Now the canopy.

The canopy is help on by a nylon 1/4 UNC bolt. A 1/4" ply plate needs gluing into the rear of the fuz and securing with two small screws.

Image

The canopy comes pre assembled and fitted perfectly but the really critical part of adding the 5 retaining hooks is left to the builder. The slots for the hooks are already CNC cut in the canopy floor so its simple a case of cyanoing them in one by one after filing the slots and then reinforcing with hysol.

This method of retaining the canopy is classic BVM and indeed is indentical to my super bandit.

Although a relatively simple task, it is vitally inportant to file the slots in the fuselage accurately becuase if the canopy was slight off then it would look awfull and I would hold my head in shame!

Anyway after taking many measurements I filed each slot in turn until I had all 5 fitting perfectly!

The font hook.

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The rear hooks

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The slots in the fuselage

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BTW its a good job I ignored the moulding marks that are in the fuselage as they were slightly wrong.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 8:29 pm

Here is a general view of the front fuselage half.

Its one big model!

Image
Last edited by Geoff White on Fri Jun 29, 2007 9:04 pm, edited 1 time in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 8:36 pm

Next comes the tailplanes mountings

The tailplanes come with the metal tube and CF rod preinstalled. I gues they are made on a jig.


Image

The metal brackets are already installed in the fuselage so its just a case of installing the beech block to set the incidence of each tailplane. Here is an dry fit of the beech block,

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Note the grub screw in the bottom of the block.

The tailplane halfs are installed and the block is pushed on from the inside, grub screw done up and then tacked in with cyano.

The tailplanes halves are removed and then the block is hysol'd firmly in place.


Image

A had a slight problem with one tailplane as the Cf rod was not exactly parallel to the metal tube so although I tacked the beech block in with cyano when I removed the tailplane the friction was enough to knock it loose.

I sorted this by a slight elongation of the hole fore and aft. This doesn't matter as the block is purely there to set the incidence.
Last edited by Geoff White on Fri Jun 29, 2007 9:04 pm, edited 3 times in total.

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 8:39 pm

As already seen there is a grub screw in the beech block. In addition there is a large bolt that secures the main tailplane tube in the pre installed bracket.

Consequently two holes need drilling in the bottom of the fuselage for access. These are marked on the fuz so its a quick job.

Image
Last edited by Geoff White on Fri Jun 29, 2007 9:00 pm, edited 1 time in total.

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M J Namih
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Ultra Bandit Build

Postby M J Namih » Fri Jun 29, 2007 8:40 pm

Geoff,

It is so good to see a build review by a modeller. I look forward to the rest of it. Well done.

Moussa
MJN :D

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 8:48 pm

So now the tailplane can be mounted as shown below!

Image

Image

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 8:49 pm

Thats it for the moment guys, back to the build!

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Geoff White
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Postby Geoff White » Fri Jun 29, 2007 9:29 pm

Cheers for that Moussa.

I will try and do regular updates as and when I find the time to do some building, which at the moment is quite often as the weather is pants :(

Bring back the summer

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Ian Bailey
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Postby Ian Bailey » Fri Jun 29, 2007 9:59 pm

Summers been and gone Geoff, had'nt you noticed ? Been too busy with that ARTF obviously !

Ian B
I am going outside, I may be some time.


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