Phantom V2 - DLG - design build

[bracesport]

I am going to leave the wings in the bags for a few days to cure nice and hard.

In the meantime I have started on the fuse moulds - I am running with the split mould technique and will join the two halves in a second stage with a balloon - I am putting some 50g FG in first to give me the shell and to ensure I get into all the corners - then I will add some 100g CF 45x45 to give it the stiffness with another layer of 50g FG to complete them.

 

[bracesport]

The wing parts are pretty damn cool - my experiment with the tinted epoxy was not quite there, but a lick of paint might be on the cards - the stiffness is awesome!

 

[bracesport]

Both fuse mould halves have their lightweight FG skins now - next some CF to stiffen them up.

 

[bracesport]

I have now added some 100g CF and 100g FG into the fuse moulds - fingers crossed it will al work out well!

 

[FlyerInStyle]

I just have a question, @bracesport , I would like to know, if it was possible to use a carbon fiber strip that has a wide grid (the squares are not woven as closely together as with what you are using) , and normal epoxy, to reinforce my foamboard plane? My nose keeps breaking, and I saw you do complete magic with Carbon Fiber, and wanted to ask how do you do it?

 

[bracesport]

I think you could just use some 50g Fibre Glass over the foam with epoxy brushed on - it will lay flat easier than Carbon Fibre no moulds required.

I just have a question, @bracesport , I would like to know, if it was possible to use a carbon fiber strip that has a wide grid (the squares are not woven as closely together as with what you are using) , and normal epoxy, to reinforce my foamboard plane? My nose keeps breaking, and I saw you do complete magic with Carbon Fiber, and wanted to ask how do you do it?

 

[bracesport]

While we wait on the epoxy I am preparing the boom and tail parts - I recycled the wing mount nuts and the stabiliser mount from the V1 fuse - the boom is 16g and in total the boom and tail is 34g - adding the 4 servos and wing nuts doubles the weight to 67g - so the balance of the weight will be the wing and and the front fuse section with the battery and Rx - hopefully the nose ballast will be minimal!

 

[bracesport]

I have add the wing mount bosses and given the parts a rough up with the sand paper - I also did a quick test with the balloon inside to use when I join the halves and that all seems to be in order - time is short this week so I will let the parts cure for a few more days before joining.

 

[bracesport]

Two layers of 50g FG strips added to make the seam joint - I put some foil inside to allow the balloon to slip around a bit easier, and I ended up putting a balloon in from each end rather than over stressing one balloon - food for thought for next time - fingers crossed!

 

[bracesport]

Before I went home I noticed one of my balloons had burst - so I pulled it all apart while it was green so I could re-do the join - the fuse parts are 47g so the total for the fuse/ boom/ tail/ servos looks to be 114g.

This morning I de moulded the half parts and I am quite glad I did as they are very robust with the FG and CF layers that I used - I think I will give them a decent internal sanding to shave off a few more grams - at the moment with the complete fuse (minus the nose cone, RX and Battery) plus the wing I am 244g.

 

[bracesport]

Here is my pattern built after some quick tests - I used my plastic foil again which heat welds and does not stick to the epoxy - a hand 'bulb' pump for kids balloons seems to make enough pressure - I will do some more tests with this latest pattern before committing to join.

 

[bracesport]

For good or for bad the join is underway - two layers of 50g FG strips along the joint - foil balloon - I used cotton thread to hold everything in place before closing up the moulds which really made things easy (pulled out the thread before clamping) - now we wait!

 

[bracesport]

There seems to be a nice join which I could see down inside the fuse (couldn't get the camera to focus in the dark hole) - I removed the end blocks and glued the boom into place with its underside jig - we continue to wait!

 

[bracesport]

De-moulded the fuse this morning and it is not too bad - I will give it a tickle up and see how it looks after that - I still have my original nose cone which I may use (sadly it is weighted so if no weight is required I will need to mould a new one)! The moulding process while a tad laboured (mostly due to time constraints) is pretty simple and I don't think I would go back to other methods now - you get exactly what to plan for in the parts!

 

[bracesport]

The wing joint will be the 'lucky last' job for the year - last day in the shop today - the thickened epoxy is in for the wing screws and the joint is made - I will leave the centre wrap as a second stage and am excited to come back in the new year and start the main assembly!

 

[BlockerAviation]

Absolutely beautiful. I have one question though, could this be done without the use of vacuum bags? If not what system do you use? I would like to get into composite builds but have no clue where to start.

 

[bracesport]

@BlockerAviation - that's two questions!

I would use vacuum bagging - in my case I make a bag (many options for that) and use the vacuum line from the food sealing vac gadget (very basic) - you could probably use a small (fish tank) air pump with the inlet reversed (actually I will try that in the new year) - Vacuum bagging is super easy and gives great results - to make a good wing use a hot wire setup and for a fuse the 3D printed moulds work well.

Absolutely beautiful. I have one question though, could this be done without the use of vacuum bags? If not what system do you use? I would like to get into composite builds but have no clue where to start.

 

[bracesport]

So I promised to have a weigh in of the fuse - 69g

To recap I went from 63g to 69g doing the join to fuse pieces and gluing in the boom - there is still some trimming of the boom length and some holes to cut, but I am happy so far - you can see the 0.5mm step in the fuse for nose cone - you can also see the surface from the 3D printed moulds, but I we sand an clear coat to smooth it all up!

So a 70g fuse/ 33g servos/ 130g wing (will increase with joining and centre taping)/ 16g tail (incl horizontal stab mount) is 249g without the Rx and battery - way better than the V1, but probably I am carrying a little extra epoxy weight as I am pretty lazy in soaking up excess - lets hope not too much nose weight is required!

 

[bracesport]

Ok, back to the build after a nice summer break - job one was to do the wing joint tape - I used 100g FG for this - the simple process was to follow what others have done with the plastic backing sheet and a foam clamp - hopefully all will be well.

 

[bracesport]

a few more days off to finish the summer break - plenty of time to cure..