Ridge Runt Evo

[Jarron]

I finally started my Ridge Runt build. Very impressed with the quality of the balsa and the laser cutting. Mine will be the electric version using the Emax XA 2212/1400 motor. With a 8x4 folding prop, what would the amp pull be?

You'll draw 17A on 3s. Why the 8x4 though? The 7x4 we use makes gobs of power with that motor on lightweight airframes like this on only 12A.

 

[Wayne]

Hey guys - Great to hear from you on the builds.

@zeo0nie1 -

1. For wing twist, you can twist the wing while heating it up with the iron or a heat gun. You will see some waves form in the covering, just apply heat to those to shrink the covering some more. You will need to "over twist" slightly. Also, make sure the aileron is not twisted before going after the wing.
2. I like to mark the location for the bend with felt tip pin. Then use some needle nose pliers to make the bends. For the tail you only need a simply 90 degree bend, not a Z bend. For the ailerons, Z bends are a good option if you have not glued in the control horn to the ailerons.
3. Drilling out the servo horn - Good question. We should add this to the guide. My old school trick is to cut off about 1" of extra wire with some wire cutters, and chuck that up in a drill or dremel, and use the "cut" end of the wire as a drill bit. Perfect sized hole every time. If you have a drill index, then I use some calipers to match to the correct drill size.

Here is a pretty good drill index if you don't mind spending some money, many uses in the hobby and around the house:

Cobalt Fractional, Number, and Letter Index Drill Bit Set, 115-Piece

Amazing deals on this 115 Cobalt Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Wow, the prices went way up on these! Here is a more practical price for a smaller kit:

Titanium High-Speed Steel Index Drill Bit Set, 29-Piece

Amazing deals on this 29Pc Titanium Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

I've been pretty happy with these drills, but I try to take good care of them too. We have some simple rules for drill uses here at the shop. Only one bit out of the kit at a time, and no drilling hard metal without a drill press and the correct speeds and lubricants. Those simple rules will make your drills last a very long time. (could start an entire thread on how to use a drill bit, or how not to use one.)


@stephensackro - Pretty sure you will be fine using the original bulkhead and servo tray in front of the wing. We ended up with a bunch of nose weight on the electric prototype after moving the servos under the wing. The 7x4 will have plenty of power with that motor.

 

[stephensackro]

Hey guys - Great to hear from you on the builds.

@zeo0nie1 -

1. For wing twist, you can twist the wing while heating it up with the iron or a heat gun. You will see some waves form in the covering, just apply heat to those to shrink the covering some more. You will need to "over twist" slightly. Also, make sure the aileron is not twisted before going after the wing.
2. I like to mark the location for the bend with felt tip pin. Then use some needle nose pliers to make the bends. For the tail you only need a simply 90 degree bend, not a Z bend. For the ailerons, Z bends are a good option if you have not glued in the control horn to the ailerons.
3. Drilling out the servo horn - Good question. We should add this to the guide. My old school trick is to cut off about 1" of extra wire with some wire cutters, and chuck that up in a drill or dremel, and use the "cut" end of the wire as a drill bit. Perfect sized hole every time. If you have a drill index, then I use some calipers to match to the correct drill size.

Here is a pretty good drill index if you don't mind spending some money, many uses in the hobby and around the house:

Cobalt Fractional, Number, and Letter Index Drill Bit Set, 115-Piece

Amazing deals on this 115 Cobalt Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Wow, the prices went way up on these! Here is a more practical price for a smaller kit:

Titanium High-Speed Steel Index Drill Bit Set, 29-Piece

Amazing deals on this 29Pc Titanium Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

I've been pretty happy with these drills, but I try to take good care of them too. We have some simple rules for drill uses here at the shop. Only one bit out of the kit at a time, and no drilling hard metal without a drill press and the correct speeds and lubricants. Those simple rules will make your drills last a very long time. (could start an entire thread on how to use a drill bit, or how not to use one.)


@stephensackro - Pretty sure you will be fine using the original bulkhead and servo tray in front of the wing. We ended up with a bunch of nose weight on the electric prototype after moving the servos under the wing. The 7x4 will have plenty of power with that motor.

Even with the motor up front you were still tail heavy? How did you make up the push/pull linkage?

 

[Wayne]

I think someone asked if they are to glue the plastic housing for the phrods to one another... NO! The smaller is a bearing surface free to slide back and forth in the larger housing.

Yes, we needed nose weight with the motor and battery under the canopy. I think we had a pretty small battery in there as it was what we had handy.

 

[zeo0nie1]

1. For wing twist, you can twist the wing while heating it up with the iron or a heat gun. You will see some waves form in the covering, just apply heat to those to shrink the covering some more. You will need to "over twist" slightly. Also, make sure the aileron is not twisted before going after the wing.

Good tips, thanks. I fixed it a bit. Will see how it flies

1. I like to mark the location for the bend with felt tip pin. Then use some needle nose pliers to make the bends. For the tail you only need a simply 90 degree bend, not a Z bend. For the ailerons, Z bends are a good option if you have not glued in the control horn to the ailerons.

This worked well. I'm very glad that I read this before I glued the aileron horns in.

Edit: also, I was within inches of gluing the the inner pushrod sleeve before reading another comment of yours. Might want to drop something into the build instructions.

1. Drilling out the servo horn - Good question. We should add this to the guide. My old school trick is to cut off about 1" of extra wire with some wire cutters, and chuck that up in a drill or dremel, and use the "cut" end of the wire as a drill bit. Perfect sized hole every time. If you have a drill index, then I use some calipers to match to the correct drill size.

Nice, thanks. Finally, an excuse to use the Dremel snake extension that I've had forever. I should use it more!

Here is a pretty good drill index if you don't mind spending some money, many uses in the hobby and around the house:

Cobalt Fractional, Number, and Letter Index Drill Bit Set, 115-Piece

Amazing deals on this 115 Cobalt Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

Wow, the prices went way up on these! Here is a more practical price for a smaller kit:

Titanium High-Speed Steel Index Drill Bit Set, 29-Piece

Amazing deals on this 29Pc Titanium Index Drill Bit Set at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

I've been pretty happy with these drills, but I try to take good care of them too. We have some simple rules for drill uses here at the shop. Only one bit out of the kit at a time, and no drilling hard metal without a drill press and the correct speeds and lubricants. Those simple rules will make your drills last a very long time. (could start an entire thread on how to use a drill bit, or how not to use one.)

Cool, I'm due for a HF run.

It's almost ready, just need to sort out the innards. With a 450 mAh battery, the 95g of ballast that I have on hand doesn't move the CG enough. I don't know if this is normal or just another artifact of my building... ah... style.

Maiden soon!

 

[Wayne]

Even though I extended the nose some over the original plane, they still need a good bit of weight up front to make CG. This is part of the fun of some vintage designs, we fly with much lighter gear and batteries these days, and if you stretch the nose too much it alters the classic look. don't worry, she carries the weight just fine, actually will fly smoother with the extra weight on board. Just place it far forward as practical.

 

[stephensackro]

If my eyes and straight edge are correct, it appears that there is a slight bit of dihedral that should be in a completed wing? With one wing panel flat on the table, what would be the block up height for the other wing?

 

[stephensackro]

If my eyes and straight edge are correct, it appears that there is a slight bit of dihedral that should be in a completed wing? With one wing panel flat on the table, what would be the block up height for the other wing?

Would someone with a completed wing kindly take a measurement for me.

 

[The Bluehead]

Mine came out at 5/8th of an inch.

 

[stephensackro]

Mine came out at 5/8th of an inch.

Thanks, just what I needed. It would be useful if Wayne would put this in the construction drawings.

 

[The Bluehead]

I thought that I read the center section set the dihedral, I couldn’t find it in the directions, but I did find it in the build thread.

 

[stephensackro]

I thought that I read the center section set the dihedral, I couldn’t find it in the directions, but I did find it in the build thread.

I thought the same but couldn't find it either. Buy relying on the center section to set the dihedral , if you are off a tiny bit, it would make a large difference at the wing tip. Blocking it up works best.

 

[stephensackro]

Bluehead, what type of hinges did you use for the elevator and ailerons ?

 

[Wayne]

The dihedral angle is set and will build out correctly as the carbon spar caps force the correct angle.

 

[The Bluehead]

Thought so, thanks Wayne. Just couldn’t provide where I had read that.

I used clear doculam film for the hinge Stephen.

- Will