bracesport DLG

[bracesport]

@Wildthing - I definitely need a better contact (especially as my wing is a tad heavy too)! 🇰🇷🌪(my son picked the emojis)

 

[bracesport]

@Wildthing - I started stripping my DLG today - I am removing the pushrods and will attempt a pull spring setup after drilling as many holes in the stabilisers as I can to remove weight - I am also thinking to move my servos/Rx/battery forward to help with CG - If the hole saw works on the FB I will consider removing wing material but more likely I will build a new wing!

 

[bracesport]

@Wildthing - tail lightened a little bit and 2x 0.8mm pushrods removed - the tail is a bit rough (tape over holes rather than shrink film), but this can serve as a test - dropped by the fishing rod shop and the kind man there gave me 3m of kevlar braid for the pull strings - now I need to make the springs!

@flyboa - what gauge wire do you use for you springs (I see Andrew Newton uses .04mm - also, Andrew Newton bends a simple 'U' shape for his springs, but I thought it is likely they are a 'Z' bend (tails at 90 deg to each other)?

 

[flyboa]

what gauge wire do you use for you springs (I see Andrew Newton uses .04mm - also, Andrew Newton bends a simple 'U' shape for his springs, but I thought it is likely they are a 'Z' bend (tails at 90 deg to each other)?

I use the same wire. "U" shape works fine for your stronger servos. For weak servos I bend to about 90 degrees.

 

[bracesport]

@flyboa - I got some 0.4mm wire and when bent up @90 deg and 5cm spacing feels surprisingly stiff - I might space the bends I tad wider.

Also picked up some ADAMS (DTFB) sheets today, so In all likelihood, I will make a new wing!

 

[flyboa]

@bracesport experiment with different lengths to get the correct stiffness. New wing is better. Any cuts in the outside paper will weaken the wing.

 

[bracesport]

@flyboa @Wildthing - I will make a new wing on Friday and keep my original (non-Adams) wing for something else - I see flyboa's wing weights are about 70-80g @1.5m so that will be the target!

 

[flyboa]

@bracesport there is still a lot of weight savings you can achieve by using a lighter boom and 1/16" balsa tails.

 

[bracesport]

@flyboa - might need to start again!

 

[bracesport]

So it is back to the drawing board

1- I will get some balsa wood for the tail (bass wood was a rookie mistake)!

2- redo the fuse with some more material removed from the pod - we have experimented with 0.1mm layers which give an awesome finish, so now I will try 0.6 wall thickness

3- I have some new (DTFB-Adams) FB to make a couple of new wings!

4- target flying weight 180g

 

[flyboa]

@bracesport when I used a 3d printed pod it was not structural. It still was easy to damage which required some CA to repair.

 

[bracesport]

today I am printing a new modified fuse pod @0.6mm and 0.15 layer thickness - I added a bit more surface to the wing attachment area and lengthened it 5cm to get the weight forward - total weight should be under 40g.

 

[flyboa]

I bought these 3D printed pods that worked pretty good. Weighed only 17g but were quite fragile.

 

[bracesport]

@flyboa - my finished weight will hopefully be lighter than the CAD weight - as the fill is not 100% - my 1.0mm walls were very strong, so I am keen to see what's 0.6mm is like - we shall see!

what thickness are your stabilisers?

 

[flyboa]

@bracesport 1/16" or 3/32" depending how light I want to go.

 

[bracesport]

Wings are underway - I chose to hotwire by hand using my wire guides - the Adams (DTFB) with paper removed on one side curls a bit so I had to be careful with the cutting - the blanks turned out quite good and only required a small amount of sanding to even out the edges - the bottom half has the TE taper from the chord line - the top half has tapers from both LE and TE from the chord line - the bottom half is also tapered to the wingtip from 150mm in - I also inserted a 3x1mm CF flat into the lamination - the wings are glued and are in a Vacuum bag - it is a waiting game now!

 

[bracesport]

stage one - wing blanks seem pretty good - total weight is 90g with the embedded 3mm CF flats - 3D printed fuse @0.6mm wall also seems pretty good - extra surface for attaching the wing will be useful - I will clean up the parts, assemble the fuse sections and then weigh.

 

[bracesport]

@flyboa - the 3D printed fuse @ 0.6 is still not as light as yours - This fuse is longer than the last one to push the battery out further - I suspect you don't have the subframe tray for the servos - I am thinking to make some holes in the sub-tray where the cover goes over it (double thickness) - I am under 50g for the complete fuse but I was hoping for slightly less!

 

[bracesport]

feathers next - I used 2.0mm balsa and the cut pieces weighed 15g - I wiped some epoxy onto the surfaces and put them in the Vacuum bag for a bit of added strength - hopefully, the final weight will be about 17g!

 

[flyboa]

@bracesport looking like around 250g AUW. With a good wing airfoil it should still float.