VP Model, NoBody (3.8 meter F5J type foamy)

[Konrad]

I recently purchased a VP model NoBody on the secondary market. This was a NIB purchase and the seller was going to pay shipping. So why not.

 

What was driving this purchase was that I'm currently flying a Top Model 3.2m Samsara for the last 4 years and she is getting long in the tooth. Meaning I need to take her down for some much needed maintenance and a recovering. What I really liked about the Samsara was that she is sporting a 1.8m long fuselage. This is key to allowing her to signal air (hopefully lift). This is so much better than the normal 1.5 meter fuselages.

 

This VP Models NoBody has a 1.8 meter long fuselage.  True this is a pod and boom fuselage rather than a one piece molding. And some of this length is going forward to aid in balance. This VP Models fuselage addresses one of the few issues I had with the Samsara in that the nose of the NoBody is pointed down to meet the up coming air, I love this feature.

 

Searching the web I'm not finding much on this model. It does look to be an older design. And looking at the spec's this is NOT a full blown F5J model as the weight is coming in at 1.8Kg closer to 2.Kg. I think I'd classify this as a very high performance sport model that won't embarrass you should you find yourself at a local F5J contest. That is to say I and most pilots won't be equipment limited flying the NoBody. About the only thing I found in english was a write up on the USA distributor's Aloft Hobbies sales page. Having now held the model in my hands I see some discrepancies in what got and what Aloft is showing in the  spec's.

 

The first and most egregious error is that the wings of the NoBody are NOT of a "D" tube type configuration. My NoBody is sporting a Leading Edge (LE) with a carbon "C" cross section. "D" and "C" cross section wings have very different performance profiles (flex and life expectancies). Now the wings do have a web that ties the upper and lower carbon LE sheeting to the wing joiner tub. This sort of looks like a "D" cross section in the area of the joiner tube. I really like this web as opposed to some other designs that just use partial ribs to tie the wing joiner to the LE sheeting. Another mis-characterization is that the Nobody is not sporting a shoulder mounted wing. The wings are 3 piece with the center section is bolted to the top of the fuselage. 

 

As I did not receive this from Aloft Hobbies but rather in the secondary market I can't complain. But if you are looking at some models from VP Models to give the photos and write a real close examination. 

https://alofthobbies.com/collections/electric-gliders/products/no-body-3-8m-by-vp-models

 

Now I'm suffering from a lack of foresight. I purchased this model wanting a replacement for my Samsara here in San Francisco but I had the Nobody shipped to my family home in Denver. This really doesn't help with my need to find a replacement for my Samsara while I have her down for maintenance. I do have a Multiplex Lentus here in San Francisco that I should use as my Samsara stand in.

 

As I said I couldn't find much written on the NoBody model. So I'd like to ask the hive mind of RCM&E what experience you might have with this model.

 

 

[Konrad]

Yikes, I see that the fuselage for the NoBody is a full carbon lay up. As such it is NOT a 2.4gHz safe fuselage. This means that all the RX antennas must be placed outside the fuselage. I wonder how old this design really is. I haven't seen a non 2.4gHz fuselage since the turn of the millennium.  

 

Also of note the canopy is also a full carbon lay up. Other than marketing I see no advantage of this. In fact it looks like another attempt to keep RF signals out of the fuselage. because I don't think there will be much of a chance for the RF signals to reach inside the fuselage where I normally place the 900mHz antennas. I've decided to try FrSky's Twin system. This is a dual band system where there are two separate 2.4 GHz RF sections operating all the time (true redundancy). I know this will result in the NoBody looking like a porcupine with all the 2.4gHz antennas pointing out of the carbon fuselage. This will be a good test of the twin system as the NoBody is about 1/4 the cost of my usual 4 meter ships. Along with testing the twin system this will also be a test for FrSky's F-Port servos. This will cut down on the wiring weight but also give real time telemetry as to servo loads (amp draw) and temps (pending over load).

  https://alofthobbies.com/collections/modules/products/frsky-tw-lite-pro-module   https://alofthobbies.com/collections/frsky-twin/products/frsky-tw-gr8

[Konrad]

Been spending some time planning (something the wife says I fail to do 🤔). I'm having some concerns about the servo mounting in the wings. I see that VP Models has provided a lot of support to the servo pocket with the addition of the carbon tongue in the top skin lay up. I'm sure this is more than adiquate for any flight loads. My concern is to build a model that will survive my landings. 

 

I'm thinking of lining the foam servo pocket with some carbon tissue. This should not only add some stiffness but it should add a lot of strength as I will be tying the pocket to the bottom skins. Normally I'd do an overlay onto the skin. But I don't want to damage (much) the bottom skin's finish. I'm thinking of under cutting the foam 1mm or 2mm to leave a small pock to allow the formation of an epoxy Cab-O-Sil bead under the bottom skin. To help with the one wall I'm going to remove part of the plastic wire tunnel.

 

Another concern of mine is that I'm planning to use an undersized flap servo. Undersized as in an 18 gram servo with what I think will be too small a gear train for typical flap landing shock loads. To address this I'm planing to use an external bearing supported servo tray in conjunction with override springs on the flap push rods. 

https://alofthobbies.com/collections/servos/products/frsky-xact-hv5101-6-8kg-94-4-oz-in-0-10-sec-18g-wing-servo

 

[Konrad]

Here are what my flap push rods look like on my 3.2m 1.9Kg Samsara. I'm planing to use much the same setup on the 3.8m Nobody. It is interesting to note that before I used the override spring push rods I suffered a stripped gear box at a rate of close to one every other landing. With the override spring I think I'm sill on the same set of servo gears.

 

What I'd like folks to notice is that the flap horn is set way aft of the hinge line to maintain leverage when the flaps are down (80° to 90°). This does result in a non-linear flap response and should be addressed in your radio setup (programing). At the weight I think I'll be flying, I'm thinking that the spring should be wound from 0.50mm wire.

[Konrad]

I’m now in Denver and have met the NoBoby personally. Wow I’m impressed with the engineering and basis quality of the model. 
 

love that I see a sub LE wrap of carbon fiber tying the upper and lower composite skins together. Many designs just rely on the strength of the glue to tie the upper and lower skins at the LE. 
 

Now I need to make a major correction the NoBody does have a “D” tube wing on both the inner and outer panels. 
 

Earlier I asked my flying partner to take a look and he couldn’t find the rear web that would make the “C” cross section a “D” tube. I had to dig deep into the foam core to find this web and really happy to have found it. 
 

There are some other points I really like about the engineering, like the foam is a real nice high density foam. I haven’t seen this in the USA. I did find a brand name and it looks like foam came from Spain. The foam isn’t as dense as what I recall Dow Spider foam was like but it is dense. 
 

[Konrad]

I’ve hit my first configuration issue. Per the sales sites it is advertised that the nose can fit 32mm spinners. 

 

I don’t know if this unique to my particular NoBody fuselage or is typical. But, I can’t fit a 32mm firewall (motor mount) to the nose of the fuselage.  The motor mount just falls through. It is so louse that I cant even pilot on the OD of the retention ring of the CN motor mount. 

 

It looks like if the nose was 8mm to 10mm longer the nose tapper night have allowed for 32mm spinners.

 

As a result of the short nose or oversized fuselage diameter, I’ve had to build up the nose with a few layers of 150 gram fiber glass. 

 

Here are some in process photos. Key is that I had to roughen the ID of the nose to allow sufficient teeth to allow the epoxy to bond to the fuselage. As this glass sleeve will be taking all the loads from the motor and much of the landing loads I’ve prepped the inside aft for over 90mm.  I’ve found that I can’t do a continuous fiber layup on ID features. As a result I pieced the nose extension allowing me to keep the glass layers against the ID of the nose.

 

I’m showing how ugly the layup looks as I wait for the initial set of the epoxy. While the epoxy is green (set but not hard) I trimmed the glass as shown. I have so many layers that I can’t fit the firewall inside the fuse. I’ll have to wait until the epoxy is fully cured to allow me to grind the  ID of the nose to a snug fit with  the firewall/motor mount.

[Konrad]

Now I should mention that I was very impressed with the tail boom stub. The sides of this stub were  laid up with the outer surface having a peal ply (shark Skin) surface finish. This is a much better prep than what we can get by roughening the bonding surface with sandpaper.

 

[Konrad]

Well, that worked out better than I had hoped. I now have a very solid press fit nose mount.

I’m wondering if I actually have stronger nose with all that added glass.

[john stones 1 - Moderator]

Nice work Konrad.

[Konrad]

Thank you John.

 

I too am impressed with the results. Particularly when one realizes that I’m not in my workshop. Here at the family home in Denver I’m using little more than a pair of scissors, a knife, sanding block and drill motor.

 

I haven’t glued in the motor mount as I have to assemble the motor and ESC and index them to allow the batteries to fit. With the limited space in today’s narrow fuselages one needs to think 3 or 4 steps ahead in the assembly process. 

[Konrad]

WOW, 

 It really is fun to be building a model where the designer is showing some obvious engineering acumen! I’m really liking the sliding block wedge for the vertical fin mounting.

 

[Konrad]

Here I’ve fitted the firewall (nose ring mount) to the fuselage I’m really liking that from the outside we are only seeing about a 2mm ring of fiberglass to allow a smooth transition from the fuselage to the ring and then the spinner.

 

This is also the first time I’ve used West Systems SIX10 epoxy glueing in the nose mount.

 

When setting up the motor mount, not only are we concerned with the thrust line but we are also concerned about hoe the motor is indexed. Here I wanted the wires from the motor to be at the bottom to allow easy access to the batteries by keeping the ESC out of the way. With my particular motor this ment that I placed the mounting screw holes about 10° off the center line  

 

With the rather fat, great sport, fuse I couldn't get the CN 11 x 8 blades to lay flat against the fuselage. I’ll need to look for a set of blades that has a rather large pin off set. I recall that Graupneer use to offer such a blade design.