RC Groups

RC Groups
    Scale Kit/Scratch Built
        Build Log 1/6 Scale Ultralight

#1 Marked Jul 01, 2012 05:16 PM

1/6 Scale Ultralight
1 Attachment(s)
Since I have this plane,why not do a model of it?
It is a Kolb Ultrastar,1983 or so,which me and my friend Tony helped me rebuild.

The front isnt original,looks and flies better,,,and is very comfortable.

#2 Marked Jul 01, 2012 05:27 PM

1 Attachment(s)
The frame is made of fiberglass rods,since I had them in my pile of stuff.
Boom tube is a section of fishing pole. Thin and light,it is also the correct size scaled down(the real one is 5")

I used thread to bind main parts together,will later cover them with epoxy and sand smooth...or will try..:rolleyes:

If anyone has better ideas joining the rods together,let me know. I am just using superglue then epoxy.

#3 PittSpecial Jul 01, 2012 08:01 PM


#4 GravyBones Jul 01, 2012 10:39 PM

This is awesome. I was in an ultralight once and loved it. Glad to see you scale down to RC level. Any vids of your full scale flights?

#5 Marked Jul 01, 2012 11:02 PM

Pitts may have some. I have several with the camera mounted on the wing facing inward. I also have one of a deadstick landing.,..plane kept hitting thermals. Utube...look up kpt417 there may be some there.

#6 Marked Jul 02, 2012 12:43 PM

4 Attachment(s)
Here are more pics of parts I have made. The pulleys are stacked washers glued together. I will change the other fittings several times before Im done.

#7 PittSpecial Jul 03, 2012 06:10 PM


#8 Marked Jul 03, 2012 06:43 PM

2 Attachment(s)
The real plane folds up...so I am doing the same. The crummy shots are the result of 10+hours of designing,building,rebuilding....multiple times until I was able to move the elevators,then fold the tail up without disconnecting anything. Elevators and rudder are cable operated.

#9 Steve85 Jul 04, 2012 10:53 AM

Neat techniques, Mark. I've used kevlar fishing line and epoxy to bind carbon fiber and fiberglass tubes together in the past. It seems to hold up pretty well. Keep on posting!


#10 Marked Jul 04, 2012 11:57 AM

The foam surfaces are for fitting only...easy to modify ..will probably frame the final controls...since I am trying to keep weight off the tail.
Seems like most scale models get tail heavy fast. :rolleyes:

#11 simano Jul 04, 2012 04:17 PM

Hey Mark,

I just found the thread. The build looks great so far!!.

Let me know if any of my tools or building materials can be used as I have quite a bit of stuff laying around as well.

I will be following the progress regularly!!


#12 Marked Jul 05, 2012 04:11 PM

2 Attachment(s)
the landing gear was a challenge.the rear view is 1in too high..I forgot to take the wheel diameter into my calculations. So unsolder and recut the back legs..after 1 Hour+ fitting the wrong ones:mad:

I reset the height of the fuse and taped it down,front(on old tx) middle,taped on the side of a box,rear,taped to a plastic box. there it sat on the floor for 3 days. the middle of the cross tube(taped flat on the floor) will be cut out,at least 7 1/2 " of it.

#13 Marked Jul 06, 2012 07:57 AM

2 Attachment(s)
This shock design is from the Legal Eagle ultralight.

pic 1 ....it works like the Cub gear,pulls outward,the opposite of a R/C car shock.
There is a slit in the outer tube,the inner tube has the pin that compresses the spring. Its a little hard to see at first,but I figured it out enough to have it on the full size one. The original design had no shock,just a solid tube...this resulted in many gear failures,unless you landed softly EVERY time.

pic 2....the assembled shock. this is better than bungees,you can change springs or add washers in if you add weight to the plane,or rough terrain.

It was hard to make them so small,and have them function.Im sure others on this forum who have better machinery could do better. I just used a Dremel tool for all machine work...its all I have:D ...and a bunch of bits;)

#14 Maurice Pudlo Jul 06, 2012 08:50 AM

The quality seems fine to me considering your tools. I like your creative use of materials (the fishing rod in particular).


#15 Marked Jul 06, 2012 09:15 AM

I still need to clean up all the parts and fittings..a paint job will go a long way. The majority of the airframe is black.

All times are GMT -5. The time now is 05:28 PM.