While visiting one of the fields this week, I ran across a plane called the yard arm, made with a tomatoe stake for a fuse and FFF for wing and stab. A less than $30 build including motor and ESC.

I flew the yard arm and decided it would make a great little indoor flyer if scaled down, so when I got home I drew up a set of plans for a 3mm version which I named the 'Super Simple'.

I had a Sukhoi BNF which was pretty beaten up that I had bought just for the brick which I intended to use later in somehing just like this. I removed parts from the Sukhoi to put on this bird.

I suspect if you had a Vapor or other bind and fly aircraft that you no longer fly, you could use the parts from just about any of those planes.

The 'Super Simple' AUW is 1.15 oz

I had to lengthen the wires from the motor to the AR6400 brick by about 2".

Scrap 6mm Depron were used on the motor mount and optional brick cover was hand cut from 1mm scrap I had laying around.

When gluing the wing halves together, you want to end up with a 15 degree diheadral. I probably should have cut a template out, but I just eyeballed it.

The leading edge of the wing is glued onto the 3/16" fusealage stick (from Ace Hardware or Lowes or Home Depot) 3" back from the tip of the fuse with Gorilla glue.

I used Gorilla glue for nearly everything on this plane. Be sure to put masking tape over any seams to prevent the glue from gobbing up. When you peal it off, the excess glue will go with the tape.

I used the landing gear from the Sukhoi and made a mount for it out of scrap 6mm foam and glued it to the underside of the wing and fuse at the leading edge.

The wing is a KF airfoil. I glued the KF strip to the underside of the wing using Aileens Tacky glue.

Blenderm tape was used for elevator and rudder hinge.

The propeller was swapped with a GWS 5030 using a mod kit I got from Neal at Graves RC. This prop slows the plane down and gives it more torque.

I put about 2 degrees of right thrust and 2 degrees of down thrust in the motor mounting.

Maiden flight was right on the money. Did not have to trim anything! Surprised even me! I was guessing as to where to mount the wing, where CG should be and had no idea as to whether or not I was in the ballpark, but it came out far better than I expected. I was all prepared to have to make 2 or three before getting it right, but luck was with me.

Cutting power, the Super Simple glides in for a greased landing. Couldn't ask for more.

I will probably scale this up and make a larger version out of FFF. It will make a nice trainer for some of the new fellows and won't break the bank outfitting it.

By the way, I use a 1/32" bit for cutting 3mm foam. I edited my constants.rb file to remove the FFF fudge factor and set the material depth to just a tad over 3mm because the 1/32 bits have very little cutting area and if the bare shank gets into the foam it melts it. I like the smaller bits because they give a cleaner cut. You can modify the SU file if you don't have one of these bits. Attached files SuperSimple.cnc (7.2 KB)Â SuperSimple.skp (99.3 KB)Â

 

Awesome plane!

Can you elaborate on this, cause I'm having trouble figuring out what the standard "fugde factor" is, and I have different cutting depths all the time. (Like do you put the bit against the material and call that zero, or keep some distance?) result: fold lines going too deep, or not deep enough (I do not use wavy FFF, as we do not have that here in Holland, but besides Depron, we have something called "Polypron" which is tcomparatively priced with FFF, it comes in nice 6mm x 1meter x 1meter white plates and is a little "softer/more bendable" than depron)

Like Randy says:-"we need absolute depth control!"

Martin

 

Flash you've outdone yourself on this one. I really like it. Looks like it might take a beatin' too

 

The next version of phlatscript will have a parameters setting for this, but for now, you simply need to edit the constants.rb file to change the inside and outside cut depths to 100.

You will find them at around line 130. Change the 140 to 100 and that will remove the overshoot that is in there for FFF.

$cut_depth_factor_inside = 100
$cut_depth_factor_outside = 100

Now, once you have removed the overshoot, you need to make sure you set your material depth to the exact depth you wish the tool to plunge.

This will depend a lot on your particular phlatprinter and the material being cut. Assuming you are cutting foam and the rollers are pressing the foam flat against the table top at the cutting bit, you can just set the cut depth to 3.2 or 3.3mm and you should be fine for 3mm Depron.

The cut depth factors only affect the inside and outside cuts, so your tab depths will be accurate regardless. I like to set mine to 60 percent. That makes it easy to trim parts away, sometimes a simple push will break them free.

If you are cutting harder materials such as plywood, you would need to zero your Z axis just where the bit touches the bottom of the material being cut rather than zeroing it at the top of the table.

Hope that clears up the mystery for you... if not, PM me and I will explain further.

 

Thank you sir!