Cutting Tail Parts

Tonight I layed out the long H Stab and V Stab parts and got them glued down and cut out all the parts. Time, about 2 hours.

I just loosely cut out this template in the interest of time and it actually ended up making it easier to see the line when I was cutting them out.


All the parts for a complete horizontal and vertical stabilizer. They just need to be sanded to match each other so my wing surfaces are nice and flat and symmetrical.

H Stab part cutting

Today I printed the rib templates and got them trimmed and taped together. I had the chance to get one rib cut out. 

I rough cut out a piece from the 1/4″ stock, then lay the HRB1 template on it and sprayed a light coat of paint. I was left with a nice silhouette to cut out on the band saw.

After cutting I sanded the edges smooth.



The result was perfect, but it took a long time to cut out the small piece with a knife and paint it. Tomorrow I will make the spar template and then spray glue them all directly to the laminate. I thin I can get all the spars and ribs for both vertical and horizontal stabilizers and elevator from this one piece.

H-Stab 2

I just finished the reverse side 1/4 foam that will become the spars and ribs. This time I mixed my micro super thick and spread it really thin. This made us easier to get it flat and I feel helped avoid bubbles under the BID. 

I again used the bias cut method for cutting the BID recommended in the manual. It worked great and the key was how I rolled up the fabric after cutting it. The first piece I rolled with the longest edge exposed and unrolled it along the 24″ length of the foam. The second piece I rolled with the angle cut edge exposed and laid it on the first to get the proper overlap and unrolled it diagonally. I left the pieces untrimmed and I’ll cut the excess off after cure. I used a lot of extra resin, spread it gently very thick and gave it time to soak in before working it in to the BID in two directions along the weave and removing excess.


The back side of the 1/4″ foam with excess fabric left. I’ll trim it after cure.

Horizontal Stabilizer

Tonight marks the start of the KR-Super2 build. I completed glassing the first side of a 2’x4′ 1/4″ Last-a-foam panel and one side of two 3/8″ panels for h-stab skins. Work was done according to Chapter 2 as per instructions. 

I was initially going to use Ecopoxy for this build because it was described as odorless and non-toxic and ok for structural parts. I purchased a gallon kit. Later I became worried that is may not be a good substitute. Aircraft Spruce was not able to provide a mechanical properties of the Ecopoxy resin system and I also read that the Aeropoxy does not contain the cancer causing substance MDA and is tested by Rutan for all structural use. I switched back to the Aeropoxy. Ordered a gallon kit from Spruce 3pm Thursday and it showed up 5pm Friday with UPS ground. Not bad. That allowed me to get started tonight.

All-in, tonight’s work used about 1/4-1/3 of a 1 gallon kit. About $30-40 worth of resin.


I laid out a sheet of 1/2″ ply to provide a flatter surface than my garage floor. The plastic is to protect the wood.


I cut the BID for the first two sheets as per instructions. The final piece I straight cut. When following the instructions I only had the small triangles as waste. Straight cut definitely has more waste, but the large leftover rectangle can be used elsewhere in the future. The bias cut method proved very hard to keep the cloth weave aligned as I was rolling out the cut sheets on the micro’ed foam. It took forever to get the weave aligned again. The overlap of the two pieces of cloth is also heavier. For future glassing, I think I’ll stick to straight cut and accept the waste to make a better, light part in less time.


Above, 45 degree cut cloth laid out and trimmed to size.
Overlap of 1.5-2″


Straight cut cloth trimmed to size.


Cut BID rolled up and ready to go.


Mixing station set up. I would pour out the amount of resin needed, weigh it. Divide that by 100 and multiply by 27. That gave the exact weight of hardener to weigh out. Tonight’s project used about 1/4-1/3 of the Aeropoxy that came today.


I printed and bound the. Hold manual for easy reference.

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My first attempt at mixing micro. It was a bit hard to spread. I mixed subsequent batches thicker and it spread on much easier.

Edit – the next time I mixed the micro 1:1 by volume with catalyze resin and this consistency was much easier to work with.


1/4″ foam nearly done with micro. I used an extra large scraper to speed things along. Just had to be careful to keep it flat and not let the edges dig into the foam.

Edit – the next time I used my yellow plastic squeegee to spread micro. Though it’s smaller, it seemed to work much better and faster.


Rolling the glass on to the foam was so easy with one big single sheet. Smooth by hand to eliminate air gaps between glas and foam.


Completed side 1 of the 1/4″ panel that will become various structural parts for the horizontal stabilizer.


I did the 3/8 panels with two glass pieces cut at a 45 degree angle. This was much less wasteful on the glass, but hard to align the two pieces of cloth to get the right overlap while keeping the weave pattern intact. 


Closeup of a finished panel.


Three panels with glass on one side. The 1×2 strips will give the wing skin panels a small curve that helps them conform easier to the airfoil shape of the h stab. 

Total time start to finish, about 4 hours.