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Sep 28, 2017, 10:24 AM
Foamy and Glider fanatic
Blacky's Boy's Avatar
Quote:
Originally Posted by dz1sfb
What happened to your pictures?

Ken
I still see them. Did they disappear for everyone but me?
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Sep 28, 2017, 01:47 PM
Ken's CAD Models
dz1sfb's Avatar
Quote:
Originally Posted by Blacky's Boy
I still see them. Did they disappear for everyone but me?
Might just be my browser at work. If I do a reply to that post the link to them shows up, so they're there, but not visible here.

Ken
Latest blog entry: Mini H Quad Project
Sep 30, 2017, 05:54 PM
Foamy and Glider fanatic
Blacky's Boy's Avatar

I'm ready to maiden this baby


Well, right before I was going to make my own, the control rods I ordered through Amazon arrived in the mail today. They got installed a short time ago. I added a zip tie guide just in front of the tail, right at he point where the control rods cross to cut down on the flex.



And using an online utility I was able to convert that DX8 program to a DX9 and it imported perfectly (my DX9 wouldn't import it otherwise). After binding the rx I tested out the controls and they seem to be operating in the right direction.

I then took the time to make a balancing stand from a (2) of 1/4" dowels, some plywood and (2) pencil erasers. With this in place I tested the balance with Lipo installed





I installed a long strip of velcro in the nose so I can vary the position of the battery easily. Because of the ample room in the nose I can use a 1300mAh 3S LiPo pushed all the way up, or even a 2200mAh 3S installed more towards the CG.

So I'm just about all set for maidening this. So naturally it started to thrunderstorm. I just checked the weather and it looks clear for tomorrow. If it's not too windy I'll take it out for a maiden.

One thing I need to check. How many degrees of deflection should I set the elevons and ailerons for?
Sep 30, 2017, 09:11 PM
Ken's CAD Models
dz1sfb's Avatar
BB,
Very good. I just measured the deflection distance on my model. The ruddervators move 1/2" in both directions. The ailerons with the angled out pushrods give 1/2" of down and 0.6" of up. Aileron and elevator rates are set to 100% on high, D/R 75% Expo 50% mid setting, and D/R 50% Expo 50%. Rudder is just 100% with no expo.

Best to start at low rates and half throttle. The wing generates alot of lift, so keeping the throttle to about half to two-thirds will keep it under control until you get the ailerons trimmed for level wings. Then trim the elevator for level flight at half throttle. Then get some altitude and trim the elevator for a steady glide. You will find that there will be a power setting that yields level flight. That's the sweet spot for the throttle. If you're not getting enough response from the controls, switch up to higher rates.

Remember to take your time, and wait for the right moment. I have often found testing a new plane was less stressful without an audience.

Best wishes on the maiden,
Ken
Last edited by dz1sfb; Sep 30, 2017 at 09:18 PM.
Oct 01, 2017, 06:19 PM
Foamy and Glider fanatic
Blacky's Boy's Avatar

Well, that didn't go as planned......


The first portion of the maiden went OK. But the 1300 mAh batteries I have all have defective cells and would not hold a charge for as long as they should. It was enough to get airborne and fly a bit. And I was able to glide to the ground rather nicely. That proved that I had the balance right. I tried a 2000 Mah battery but even with me putting it as far back as I could it made the plane too darn nose heavy and cause the plane to nose in. I ended up crumpling the nose and splitting seam or two. I had a battery powered hot glue gun so I could make some minor repairs.

But in subsequent (short) flights with a freshly charged 1300mAh battery I found that the rudder was doing pretty much nothing. I could only bank, not turn. That lead to a crash,....or two. The motor mount came loose and one Vtail cracked loose from the glue joint.

<Sigh!>..........................I'm going to need to do some major repair work. And I'm ordering some new 1300mAh batteries.

Some of the other club members who are used to flying Vtails said that it might be because of the flex in the control rods. All that prop wash going over the Vtail is pushing against the ruddervons(?) and the rod will flex rather than allow the control surface to move. So I'll be adding some more guides to address this.

As I mentioned before Vtails always seem to give me a problem. Mostly because I don't understand their operation. Maybe if I understood them better I could spot trouble sooner. When pulling back on the elevator stick the ruddervons should behave as a standard elevator and actuate UP, And when pushing forward on the elevator stick should cause the opposite. Right?

Now when using the rudder stick, what should I be seeing when I move the rudder stick to the left and then to the right?

One other question, when I loaded up the DX8 program you sent I noticed that the subtrims were set. Realizing that these settings would not be the same for the model and transmitter I was using, I cleared them out and reset them. You don't think that could have been an issue, do you?
Apr 19, 2018, 07:36 PM
Registered User
XDmToter's Avatar
Hello Ken,

I stumbled upon this thread a few months ago, and I think I may build one of these. I was able to get all the parts to fit on a single sheet of MPF, including both wing options.

Do you think 1.75" of dihedral at each wingtip (about 10 total) will give it decent roll coupling on the non-aileron wing? Too much? Not enough?

It looks like a lot of dihedral in CAD, but I don't have much experience in this area.
Apr 20, 2018, 05:24 PM
Ken's CAD Models
dz1sfb's Avatar
Quote:
Originally Posted by XDmToter
Hello Ken,

I stumbled upon this thread a few months ago, and I think I may build one of these. I was able to get all the parts to fit on a single sheet of MPF, including both wing options.

Do you think 1.75" of dihedral at each wingtip (about 10 total) will give it decent roll coupling on the non-aileron wing? Too much? Not enough?

It looks like a lot of dihedral in CAD, but I don't have much experience in this area.
Keith,
That sounds and looks just right.

Ken
Latest blog entry: Mini H Quad Project
Apr 21, 2018, 07:41 AM
Registered User
XDmToter's Avatar
Excellent. Thanks Ken.

I think this will be a better fit for the electronics I have in my FT Sparrow. I built the Sparrow at 130% and I'm running a 2306 2650kv motor on it. She's a bit overpowered.
That motor is still a bit more than you recommend for the Eclipse, but hopefully it won't rip the wings off.
Last edited by XDmToter; Apr 21, 2018 at 07:43 AM. Reason: added rctimer link
Apr 28, 2018, 08:07 AM
Registered User
RobDog's Avatar
HI Ken,
You mentioned in one of your posts that you could supply a file for those of us with access to cnc equipment. Well, my brother owns a large bed laser cutter and if you could post them, or would be willing to email them to me, I'd be appreciative. There are 3 of us in my little flying group with 3d printers as well, so ill be checking thingyverse for the parts. This design looks like it would do very well with FPV equipment on it.

If it's a bother, no big deal. We can alway's just use core draw and pull the vectors off the pdfs. But having a vector ready to feed the laser software sure is faster. ....

Thanks for this design and I will post our flying videos when we get a couple built.
Apr 28, 2018, 11:37 AM
Registered User
tspeer's Avatar
Cutting polystyrene foam is the #1 cause of laser cutter fires. Just sayin. I use my laser to cut templates from 1/10" utility plywood, then use them to cut the foam using a vertical hotwire set up like a scroll saw.
Apr 28, 2018, 12:44 PM
Registered User
RobDog's Avatar
We have had good results from cutting very fast with very low power. But, yes, we had a couple of fires on a few first attempts.
Apr 28, 2018, 08:44 PM
Ken's CAD Models
dz1sfb's Avatar
Quote:
Originally Posted by RobDog
HI Ken,
You mentioned in one of your posts that you could supply a file for those of us with access to cnc equipment. Well, my brother owns a large bed laser cutter and if you could post them, or would be willing to email them to me, I'd be appreciative. There are 3 of us in my little flying group with 3d printers as well, so ill be checking thingyverse for the parts. This design looks like it would do very well with FPV equipment on it.

If it's a bother, no big deal. We can alway's just use core draw and pull the vectors off the pdfs. But having a vector ready to feed the laser software sure is faster. ....

Thanks for this design and I will post our flying videos when we get a couple built.
Hi Rob,
Here is the dxf and stl files. Use in good health.

Ken
Latest blog entry: Mini H Quad Project
May 23, 2018, 06:51 PM
Ken's CAD Models
dz1sfb's Avatar
My friend Bob recently finished his Eclipse.

Ken

Latest blog entry: Mini H Quad Project
May 25, 2018, 07:36 AM
Registered User
RobDog's Avatar
That looks awesome! Congrats
Oct 09, 2018, 05:30 PM
Registered User
XDmToter's Avatar
A little progress on my scratch build... The pieces are cut! WooHoo.


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