Hobbistar 60 - Tail dragger conversion
 

Now that the wing repair is complete, I'm turning my attention to the next project for this plane - converting it from conventional tricycle gear into a tail dragger.

The first step was to remove all of the stock landing gear.

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RE: Hobbistar 60 - Tail dragger conversion
 

Next step: Filling in the main gear channel with some scrap.

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I went with a Sullivan tail wheel. The original idea was to have it castering, but a closer look at the tail presented a different solution - taking a notch out of the elevator.

The notch was centred, but the stripes weren't.

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Re-covered...

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RE: Hobbistar 60 - Tail dragger conversion
 

After the notch was cut and covered, I ground off the heads of the plastic tail bolts, possible because the horizontal and vertical stabilizers are epoxied in place. Once that was done, I re-covered the tail.

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The tail wheel bracket was mounted with four servo screws...

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... and the steering arm was connected to the rudder.

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RE: Hobbistar 60 - Tail dragger conversion
 

Cool, Idid the same with my Tower Trainer 40 but left the tailwheel to caster , it worked OK for my flying field but your solution is quite elegant.
The plane flew a lot better as a taildragger but it still sucked and I am glad it finally crashed and burned.
Inow have a Nexstar and its much better, maybe Ican make it a taildragger too?

RE: Hobbistar 60 - Tail dragger conversion
 

Jeffie, there's a guy named chuebner on RC Canada who has converted his NexStar - check out this post for pictures.

RE: Hobbistar 60 - Tail dragger conversion
 

On to the main gear. The first step was to decide on the orientation. I chose to have it sweep back.

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There are calculations you can do to determine where the gear should go. After a lot of thought, research and advice I decided that placing the axles directly beneath the leading edge (in a level attitude) was the solution for me. To that end, I followed these steps.
[*]Eyeball the placement of the gear on the fuse[*]Mark the leading edge of the gear on one side of the bottom, 5mm from the edge[*]Insert a t-pin at the mark[*]Roughly across the bottom from the t-pin, make a short line parallel to the edge and 5mm from it[*]Pick a forward point on the fuse. Measure halfway across the bottom and insert the t-pin there[*]Measure the distance between the two t-pins[*]Mark the same distance from the forward -pin to where it intersects the 5mm line drawn in step 4.[*]Insert a third t-pin at the mark[*]The line between the two rearmost t-pins forms an accurate leading edge location for the gear

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RE: Hobbistar 60 - Tail dragger conversion
 

With the leading and trailing edges of the gear marked, the covering came off the bottom.

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There was a small gap at one point where a razor blade could be worked in...

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... but first the bottom had to be cut across. A fine-toothed back saw worked well.

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RE: Hobbistar 60 - Tail dragger conversion
 

With the crosscuts done, a razor blade fit nicely into the gap.

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A small scraper soon followed.

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With some gentle encouragement, the bottom plate came off the fuse with little damage.

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Turns out I had a hardwood block that was the perfect depth and width - it just had to be cut to length.

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RE: Hobbistar 60 - Tail dragger conversion
 

I used 30 minute epoxy to secure the block.

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While it was curing, I turned my attention to the gear itself. Drilled out the axle holes...

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... test fit the axles...

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... and marked the centre line.

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RE: Hobbistar 60 - Tail dragger conversion
 

I put the tail wheel on before work this morning - couldn't wait to see how it looked.

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I made a drilling template for the main gear based on the location of the hardwood block.

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Got the holes marked and ready for drilling.

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RE: Hobbistar 60 - Tail dragger conversion
 

With the holes marked it was time to lug my trusty drill press to the bench.

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A little protection...

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Started with the pilot holes.

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Then to an 11/64" bit for the #8 wood screws.

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RE: Hobbistar 60 - Tail dragger conversion
 

Time for one of my favourite tools - the transfer punch.

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Holes marked.

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Started with a pin vise...

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... finished with a hand drill and 3/32" bit, marked with tape for a 1/2" depth.

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RE: Hobbistar 60 - Tail dragger conversion
 

For#8 wood screws I'm not sure it's necessary to pre-thread the holes and drizzle in some CA, but I've gotten into the habit with RC so I went ahead.

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After that came the covering, then the main gear.

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I cut some brass tubing to bridge the gap between axle size and wheel bore.

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Then onto its new legs for the first time!

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RE: Hobbistar 60 - Tail dragger conversion
 

Irun a lot of four strokes and having the improved ground clearance to swing a big prop is important to me. Ialso fly off tall grass sometimes and it makes a big difference with a tail dragger.

RE: Hobbistar 60 - Tail dragger conversion
 

I hear you. This plane is powered by an OS 65 LA 2-stroke running a 12 x 6 prop, but I whacked the grass with it plenty of times while I was learning on it with trike gear. Had to replace the nose gear a couple of times too.

RE: Hobbistar 60 - Tail dragger conversion
 

Ijust hate it when my plane turns green from mowing the grass with the prop. http://www.rcuniverse.com/forum/js/f...ey/msn/lol.gif

RE: Hobbistar 60 - Tail dragger conversion
 

Together again for the first time.

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Just a little nose heavy at the rearmost point of the CG range.

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RE: Hobbistar 60 - Tail dragger conversion
 

Looks great, hope it flies as well as it looks.