Phantom V2 - DLG - design build

[Jackson T]

Ha - just lucky to have these CF tubes in the parts bin at work - the printer is doing most of the work!

I think I need a new job .

the wing weight was the major culprit as I used 100g Carbon

Did you do a single layer of cloth, or multiples? I thought ~100g cloth would be pretty standard.

They are split top to bottom through the centre and I will lay them up in their halves and then set the join with a balloon

Just did some research, the bladder technique looks really handy. How do you stop the balloon from adhering to the inside of the part?

 

[bracesport]

Hi Jackson - the go seems to be <50g cloth and the balloon does not adhere to the epoxy (luckily)!

I think I need a new job .

Did you do a single layer of cloth, or multiples? I thought ~100g cloth would be pretty standard.

Just did some research, the bladder technique looks really handy. How do you stop the balloon from adhering to the inside of the part?

 

[Jackson T]

Hi Jackson - the go seems to be <50g cloth and the balloon does not adhere to the epoxy (luckily)!

Just a plain latex balloon for animal making, or specialty balloon?

 

[bracesport]

I just use those long skinny kids balloons for twisting animal shapes - nothing special!

Just a plain latex balloon for animal making, or specialty balloon?

 

[bracesport]

I had a quick test of the cutting rig this morning - I cut a parallel section and a tapered section and both worked well - I used some MIG welding wire and cut at about 3v - I think I could have a tad more spring tension, but the cuts were smooth regardless - next I need to test the cutting with the foil templates - so far so good - exciting!

 

[bracesport]

YAY - a first run of the hot wire cutter with reasonable results - to cut a long story short this is a great cutting system, but I need to redo my foil templates - the lead in is too tight and the wire is catching in the corner - I will post some specific detail on that when its done.

 

[bracesport]

I printed the first two foils in poly carbonate and edged them with the aluminium tape - the lead-in at the LE's are much better now - the second set are on the printer now - I also started preparing the foam blocks.

 

[bracesport]

I wanted to do some more testing before committing to the cuts - this time I am using Nichrome wire which is very thin - the resistance is way different than the Mig welding wire so the power went up to around 12v - the cutting speed also increased and so I was slowing it down and caused a few ripples - I need to reduce the weight - needless to say it was good progress given it was the second cut on the rig!

That foil thickness is about 4mm!

 

[Wildthing]

VERY SLICK, you are a master designer

 

[bracesport]

I have done two rounds of foil templates and with the second set this morning I am still not happy with the lead into the LE cut - I think I would rather print a third set than waste cuts - the wire is getting caught for a second before moving into the cut so the transition radius onto the foil is too small.

 

[PsyBorg]

@bracesport You are guiding the wire by hand I assume. Why not just start lower and make the rise up the leading edge just a continuation as if it were just a longer slope? No flat land to lead onto the foil. The under cut should work fine and be first I would think. Come in flat and straight then just fall into the cut leaving a good edge to transition into the top cut where you just slope your template up to meet the lower cut and continue over the top.

 

[bracesport]

Yes that is an idea I have if these latest foils is not an improvement!

@bracesport You are guiding the wire by hand I assume. Why not just start lower and make the rise up the leading edge just a continuation as if it were just a longer slope? No flat land to lead onto the foil. The under cut should work fine and be first I would think. Come in flat and straight then just fall into the cut leaving a good edge to transition into the top cut where you just slope your template up to meet the lower cut and continue over the top.

 

[bracesport]

Another round of test cuts - I think I am getting there - cutting the tapers is working well - the issue I had at the leading edge is sorted in part by the improved foil templates and in part by slowing the entry cut down and adding slightly more heat.

I just need to find some better top weights as the foam lifted slightly at the TE and we will be on our way.

 

[Jackson T]

They're looking good! So does the weight on the string pull steadily while you guide the height of the wire by hand? I'm a bit confused.

 

[bracesport]

Apart from starting the cut, the wire is pulled through automatically (the weighted string pulls it through) - the cutting boom is counterweights to be almost weightless (biased so the boom ends float along the table - this means the cutting wire has slight downward pressure on the templates - the rig has adjustable geometry to cut different tapers.

They're looking good! So does the weight on the string pull steadily while you guide the height of the wire by hand? I'm a bit confused.

 

[bracesport]

I cut the six panels in the wing this morning - six great cuts - to cut the left side tapers I rotated the wire rig and swapped the pull string to the other side - all worked well - I need to make some templates for the plan form and then do some cleanup to make the curved edges - I was very nervous doing the cuts but I needn't have been as it all went smoothly - slow 'ease-ins' at the leading edges and I stopped the bar at the trailing edges and let the 'spring tension' of the wire pull itself out to complete the cuts.

 

[bracesport]

Some more prep - wing template and mylars are cut.

 

[bracesport]

In preparation for my Spars I have prepared a single layer of 80g CF cloth to use for strips and such if needed - one idea is to use it for the basis of my shear web and epoxy the pultruded 3x1mm flat bars onto it - it is a work in progress so we shall see.

 

[FoamyDM]

WOW you are getting Serious about this! great work so far.

 

[bracesport]

It is all deceptively simple and thrifty - just takes some planning!

WOW you are getting Serious about this! great work so far.