Help! Ft Explorer Reinforcment and Servos

[Om0r A.]

Hello everyone,
I am finishing up my Ft Explorer and I am planning on adding an aluminum bar for reinforcement inside the wing. The aluminum bar would go inside the plane's spar. However, I noticed that it seems I won't be able to do so because of the place where I need to put the servos (I'm building the sports wing). Do any of you know the solution to this? Thank you.

 

[FDS]

@Hai-Lee swears by fibre glass tape over the wing joins, before you roll the wing up. I have used that fix on a very bendy Tiny Trainer wing and it has totally stopped it flexing.
An aluminium bar is a very heavy way to do the job. If you search this forum others have a ton of cheap and light spar options for the Explorer.

 

[Headbang]

I use 2 bbq skews for support. I've put my explorer through the wringer and it has held so far. You do not need a long spar, just 3 or 4 inches inside each wing.

 

[Om0r A.]

@Hai-Lee swears by fibre glass tape over the wing joins, before you roll the wing up. I have used that fix on a very bendy Tiny Trainer wing and it has totally stopped it flexing.
An aluminium bar is a very heavy way to do the job. If you search this forum others have a ton of cheap and light spar options for the Explorer.

How can you apply this?

 

[Om0r A.]

I use 2 bbq skews for support. I've put my explorer through the wringer and it has held so far. You do not need a long spar, just 3 or 4 inches inside each wing.

How did you apply this? Are barbecue skewers strong enough?

 

[Hai-Lee]

Unfortunately the Explorer wing is almost an enlarged and re-dimensioned Tiny Trainer sports wing.

The spar is too weak for the weight of the plane when setup for speed and maneuverability.

I normally replace the original spar with a pair of dual folded spars of 10mm total thickness. With such a spar arrangement I fit the servo between the spars through a hole in the wing so that they surface mount on the underside of the wing

Added to that I fit a pair of plywood dihedral braces as well as the aforementioned fibre tape.

I hope that helps!

have fun!

 

[Om0r A.]

Unfortunately the Explorer wing is almost an enlarged and re-dimensioned Tiny Trainer sports wing.

The spar is too weak for the weight of the plane when setup for speed and maneuverability.

I normally replace the original spar with a pair of dual folded spars of 10mm total thickness. With such a spar arrangement I fit the servo between the spars through a hole in the wing so that they surface mount on the underside of the wing

Added to that I fit a pair of plywood dihedral braces as well as the aforementioned fibre tape.

I hope that helps!

have fun!

I’m really sorry, but I don’t quite understand what you exactly mean and how to do what you are saying. Could you add details with possible photos of some sort?

 

[Hai-Lee]

I’m really sorry, but I don’t quite understand what you exactly mean and how to do what you are saying. Could you add details with possible photos of some sort?

Sadly I do not have any pics of my FT Explorer as I built mine before I even had the ability to take a photo. My last Explorer was gifted away about 6 months ago now so I have nothing I can take a pic of BUT,

What I am describing as the spars and tape can be found on another and somewhat larger model I recently finished and managed to get build pics and video of. See:- https://forum.flitetest.com/index.php?threads/100-hour-replacement-build-das-ugly-stik.57330/page-2

The Ugly stick does not use any dihedral and therefore the tape in on the inside of the wing joint whereas if the wing has dihedral you should consider the tape used externally over the wing joint if you think it is required.

If you need more info I could do a few rough diagrams but I am about go flying so it may be around 4 hours before I can respond further.

I hope this helps!

have fun!

 

[kdobson83]

My vote is a paint stirring stick right in the middle of the wing. The weak point on that wing is right where the cut out is for the power pod. A pair stirring stick will add plenty of support. A cheapo carbon arrow shaft from Walmart works good too.

 

[Om0r A.]

My vote is a paint stirring stick right in the middle of the wing. The weak point on that wing is right where the cut out is for the power pod. A pair stirring stick will add plenty of support. A cheapo carbon arrow shaft from Walmart works good too.

Would a paint stirrer really be strong enough? Are you thinking of something like this? Also, every time I look for carbon arrow shafts at Walmart, they all seem very expensive. Do you have one in mind that is cheap?

 

[Om0r A.]

Unfortunately the Explorer wing is almost an enlarged and re-dimensioned Tiny Trainer sports wing.

The spar is too weak for the weight of the plane when setup for speed and maneuverability.

I normally replace the original spar with a pair of dual folded spars of 10mm total thickness. With such a spar arrangement I fit the servo between the spars through a hole in the wing so that they surface mount on the underside of the wing

Added to that I fit a pair of plywood dihedral braces as well as the aforementioned fibre tape.

I hope that helps!

have fun!

Do you think that the fiber glass tape would be enough by itself? If so, would I just apply it to the shaping joints on the outside of the wing?

 

[Hai-Lee]

Do you think that the fiber glass tape would be enough by itself? If so, would I just apply it to the shaping joints on the outside of the wing?

Unfortunately you will find that you definitely will need to cut and fit dihedral braces of some sort. I prefer ply for dihedral braces unless the wing has no dihedral in which case paddle pop sticks suffice.

The tape is to stop the wing panels from pulling apart and destroying the glued wing joint and so the tape is recommended to reduce the loosening of the wing joint. If the glue joint weakens there is increased pressure on the dihedral brace and eventually a possible wing fold.

Have fun!

 

[Om0r A.]

Unfortunately you will find that you definitely will need to cut and fit dihedral braces of some sort. I prefer ply for dihedral braces unless the wing has no dihedral in which case paddle pop sticks suffice.

The tape is to stop the wing panels from pulling apart and destroying the glued wing joint and so the tape is recommended to reduce the loosening of the wing joint. If the glue joint weakens there is increased pressure on the dihedral brace and eventually a possible wing fold.

Have fun!

I’m really sorry to nag you, but how could I make a dihedral grace and what would that look like? A non-dihedral can also work if needed. Thank you so much!

 

[Hai-Lee]

You will need to cut it from some solid material like Plywood and slide it into the ends of the wings where they glue together. You will need to apply glue to the brace before it is inserted into the wings so that it is glued in position.

Here is a simple explanatory diagram of a dihedral brace.

The angle of the "V" determines how much dihedral your wings will have and is normally measured in degrees. The height of each side should be the same height as the wing spars. The brace is glued to the wing spars inside the wings before they are joined.

The wings, (if you add dihedral) will need to have the mating faces beveled to leave little of no gap , (top and bottom), when test fitted together over the dihedral brace, (before applying any glue).

I hope that helps

Have fun!

 

[kdobson83]

Would a paint stirrer really be strong enough? Are you thinking of something like this? Also, every time I look for carbon arrow shafts at Walmart, they all seem very expensive. Do you have one in mind that is cheap?

Oh yeah, a paint stirring stick is plenty strong. Your adding it to the existing spar. The ones at Lowe's are good for bigger planes as they are long and thick, ment for mixing 5 gallon buckets of paint. Walmart has em too but they are smaller, good for pretty much any standard FT design.

And the arrow shafts, the cheap ones are $3 a piece at Walmart. The problem is they are popular and sell out fast. If you every see em in stock, feel free to grab a few. I've put em in multiple planes now, haven't snapped a wing yet, including my explorer. Oh, and they are easy to cut down to size as well for those smaller planes.

Here's the arrow I was talking about. $2 at Walmart. Says in stock at mine.

Anyway, paint stick would probably be a better option to strengthen up the center section of your wing. They are free too! 😋

 

[Om0r A.]

You will need to cut it from some solid material like Plywood and slide it into the ends of the wings where they glue together. You will need to apply glue to the brace before it is inserted into the wings so that it is glued in position.

Here is a simple explanatory diagram of a dihedral brace.
View attachment 129561

The angle of the "V" determines how much dihedral your wings will have and is normally measured in degrees. The height of each side should be the same height as the wing spars. The brace is glued to the wing spars inside the wings before they are joined.

The wings, (if you add dihedral) will need to have the mating faces beveled to leave little of no gap , (top and bottom), when test fitted together over the dihedral brace, (before applying any glue).

I hope that helps

Have fun!

Thank you so much for your help!

 

[Om0r A.]

Oh yeah, a paint stirring stick is plenty strong. Your adding it to the existing spar. The ones at Lowe's are good for bigger planes as they are long and thick, ment for mixing 5 gallon buckets of paint. Walmart has em too but they are smaller, good for pretty much any standard FT design.

And the arrow shafts, the cheap ones are $3 a piece at Walmart. The problem is they are popular and sell out fast. If you every see em in stock, feel free to grab a few. I've put em in multiple planes now, haven't snapped a wing yet, including my explorer. Oh, and they are easy to cut down to size as well for those smaller planes.

Here's the arrow I was talking about. $2 at Walmart. Says in stock at mine.
View attachment 129570
Anyway, paint stick would probably be a better option to strengthen up the center section of your wing. They are free too! 😋

One last quick question. How can I insert the paint stirrer without it being in the way of the servos? Thanks a lot!

 

[Headbang]

So just about anything is strong enough. Fiber tape along the length of the bottom of the wing will be plenty strong for normal flying. I have bbq skewers on the leading and trailing edge. My wing is also flat. It held up to some more intense inverted flying the other day. You only need a few inches on either side, so the spar should never get in the way of the servos. All options that have been presented here are good. It does not take much reinforcement.

 

[kdobson83]

One last quick question. How can I insert the paint stirrer without it being in the way of the servos? Thanks a lot!

If you use a paint stick, you put it right in the middle of the wing. It should be long enough to reach the servo holes. Your only trying the reinforce the middle/weak part of the wing where most of your stress is. The outer sections of the wing don't experience as much stress as the middle portion. The factory spar is plenty strong enough. Just glue paint stick right in the middle inside the spar. This needs to be done while building the wing btw.

 

[Om0r A.]

If you use a paint stick, you put it right in the middle of the wing. It should be long enough to reach the servo holes. Your only trying the reinforce the middle/weak part of the wing where most of your stress is. The outer sections of the wing don't experience as much stress as the middle portion. The factory spar is plenty strong enough. Just glue paint stick right in the middle inside the spar. This needs to be done while building the wing btw.

So, if needed, should I just cut the paint stick to not reach the servo holes? Also, does hot glue not work as a glue instead?