Question about VTOL

You then have a suitable profile. Sorry for the demand.
Impressive how far the construction has already progressed. A really great project.

At the end of the load cabin, on the “roof” of the parachute compartment.

Hey Rolf.
Didn’t see anything in your comment as a demand, rather and interest and curiosity. I am pleased to get them.
Yes it has come together fairly quickly, I think even faster if I wanted to start printing from scratch today. Lots of reprints as I tuned the design, this caused a lot of delays. But ya fairly quick.

Your saying the FC is at the end of the load cabin on the roof, I wasn’t aware there was a parachute compartment so no idea where this is. However I get the impression from the attached video that the Parachute is mounted on the bottom and the FC is under this panel. So I updated the design to take the FC location into account. I don’t like where I have it now and on the next build it will be where this is roughly anyway.
Fighter FC Location


My design updated with the new fc location. Will need to look into things to aid wire routing.

Interesting this vide shows the parachute location is on the underside.

Now you have caught the compartment for a GPS/compass. The FC is further ahead. I have just no better picture at hand and marked the spots:

Edit: more clear photo:

Cheers

Oh i see.
Hmmm. So i have created to much space for the gps to go into if i use it there instead of the fc. I will have a look at the fc location you referenced. Interestingly thats where i have the gps at the moment. Ok when i get home i have some tweaks to make. But its all good thanks for the information.

Thanks again for these photos they are really helpful
I updated the next version to include the GPS and FC mounting.

I have not done a parachute bay as yet, because I don’t know enough about the size of the chute folded up. I imagine with some reading I will find that.

Can I ask what size lift motor and props are those.

Oh and I love the shop.

I opted for a complete T-motor set (motor,ESC,prop): Fighter VTOL 4+1 fixed wing - #491 by Rolf.
Best you scan through the above thread. There are many helpful posts and links, especially from GregCovey, god rest his soul.

Why do you want to rebuild a parachute bay ? I think it exists because the Fighter was also advertised as a 2-mot with the option to land it regularly by parachute.

As a safety feature, that would be different, of course.

Rolf

Why the comment about Greg. Did something happen to him.
As for the parachute bay, since this is my own build and design I didn’t include the parachute…just wondering if I want to. Good safety item.

Edit:
Just did some reading about parachutes. They take up a ton of space and weigh more then I expected.

Additional Edit
I just read the link about Greg, Super sad news. I had chatted with him a few times. Super guy.
He will be missed.

Thank you for the link

Hey Rolf
Happy new year. Just finished wiring my wings. They come in at 1740grams. So close to yours. I still need to add the aileron linkage and servo cover. But thats only a few more grams so pretty close to yours. Thats also the wing with the Pitot so that adds a bit. So happy happy. I think the body is coming in heavier however. I have not properly weighed it as yet.

Cheers

Hey Rolf
So I finally got the total machine weighed.
The fuselage is 2691 grams or 2.7 KG…compared to 2.25 kg for the original Fighter.
The wings are 1.74 kg versus the 1.77kg of the Fighter.

That said, I am missing the receiver for the main body so a bit more weight there.
As well as no propeller so a little more there.

The wings need the aileron linkage and propellers…so a few more grams there but other then that they are done.
So right now it’s coming in around 6.2KG versus the 5.79KG of the original fighter so around a 400 gram difference.

I will see if there is anything I can do on the design to further reduce the weight, but I confess I am pleasantly surprised it’s come in so close.

Cheers

Congratulations Rick. The low weight of the wings with 3D printing is impressive - the quad motors and quad mounts are already weighed in there ?

Rolf

Hey Rolf
Yes thats the wing weight with the motors, arms folding mech and everything needed but the propellers and servo linkage. I went back over the drawings today looking for areas I can further reduce weight. But starting to run out of ideas. The difference between your model and mine is that mine is about 6.4% heavier right now. I imagine that will go to 7% with the last couple items. So shaving it down a bit more might be possible. Just need to think on it.
I am going to look at different printing filaments as well. Also if there are any settings I can use to reduce the weight just through printing of the parts themselves.
But at this point I need to get the last of the wiring done and see if she spins up.

Hey Rolf
I just noticed the Pitot Covers on your bird.
IS there somewhere that sells them

Hi Rick,

the ribbon comes from key chains. At e.g. amazon just search for “Remove Before Flight Red/White Key Chain”.

Rolf

cool
I ordered some from Amazon last night. Will get a straw and so heat shrink tubing and make up a cover.
I didn’t know you can get them from Amazon.

Thanks very much.

Got mine today.
Thanks for your help Rolf. As always I very much appreciate your assistance.
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You could try reducing wall count and infill density for outer wing as it sees lower loads.
Schrenk’s curve is a decent approximation of wing lift distribution.

Hi @rickyg32 ,
What you did is amazing, need long hours and hard work… I am currious to know how long you did print the whole plane? What 3D print do you use that can do such long hours ?
I just think to print wing extension using 3D print.
Regards,
Tony

Hey Tony
hard to say how long it took because I would print, find a problem, update and print again. Make improvements as I go. But if I was to do it again, print everything starting today. It would likely take about 2 weeks or less. It’s not a hard thing to print.

Hey Lupus,love that name.
Yes I am looking into changes to the printing profile. That said I am really close to the weight of the original Fighter so it’s not a lot to change.
Right now I am looking at a different approach to building the wing al together. More of a hybrid wing. Wood and 3d print. For me this is about learning so it’s all good.

As for Schrenks Curve, I have never heard of that …will check it out.

Hey @Rolf
It’s been a bit since I came back to this topic.
In the time since I tossed the build and started over. I found issues with the 3D printed parts and their in ability to stay stable and well they weigh a lot.
Anyway I went back to the drawing board and thinned out the 3d printed frame and installed a plywood internal structure. I found that the PLA was just not rigid enough to make it a viable VTOL.
So I took my original drawing and tweaked it with all the information that you provided. The down side is the body with tail is heavier then the original fighter. IF I bother to try another version I will see what can be done to reduce the weight. But so far 3D printing is proving to be a heavy solution.
I tend to use each thing I build to learn new stuff…so this time its paint and vinyl lettering.
I would love to turn this into a fiberglass hull. Would be a lot lighter.

Here is what the body looks like today. It’s fully wired.




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