CriCri MC-15 in NZ

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MadRocketScientist

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Canterbury, New Zealand, Earth, Milky Way Galaxy.
The spar is made up of the web with four angle caps top and bottom, the web is actually in three parts. There is the doubler in the middle to allow for extra strength and the fork for joining. The outer end has a thinner 0.020" piece added on the end. I think this is to optimize weight and also that the aluminium sheet size was only 2 meters long.

Not sure what the engine talk is all about, the snowmobile engines are far to big for a CriCri making it so far off topic its not funny.

Shannon.
 

danmcgee

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Mar 8, 2010
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Virgina/ USA
Ok I see this part # 100-03 0.8 largest web, part # 100-04 is also 0.8 and has the cutout and taper from 0.8 to zero and part # 100-05 picksup exactly were 100-03 stops to the end of the spar and is 0.5 thick. I do see this.

Could I ask you to post some more close up pics of your spars on the cricridrawing page in your build folder so I can see all the details as well as the wood blocks. I would apreaciate that.

Thanks for your answer that helped me understand the intent of the designer.

Dan

engines no way they would work on a CriCri thats crazy
 

MadRocketScientist

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Canterbury, New Zealand, Earth, Milky Way Galaxy.
I haven't really got that far along with my spars, I have the webs and caps cut and cleco'ed but that's about as far as it is. I haven't made the wood blocks that act as spacers for the wing pins yet. I haven't even cut the web doubler to a taper yet. Some of the pics on Cricridrawings show the detail.

Shannon.
 

MadRocketScientist

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Canterbury, New Zealand, Earth, Milky Way Galaxy.
About time for another update, I have been working on the landing gear installation. My welding isn't terribly good but it is passable, I think I will outsource the welding if I do another CriCri.

The bolt holes for the main landing gear brackets don't seem to line up properly and I can't seem to work out why. The CAD drawings indicate that they should but the clamps touch on the lower fuselage, more research is in order to see where things have gone wrong.

I hope to have more progress on the landing gear over the next few days.

Shannon.
 

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danmcgee

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Shannon, awsome update and thank you for the canopy file that is such great information. You get that tank mold done then make two and I will buy one from you. The tank or a mold would be great. Is is posible to produce a drawing for the peddle tray I could use to make one with or maybe a trace drawing if not not a big deal. I just wanted to say your post and pics have made thing so much easyer for me already and your work is outstanding.

Dan
 

vondeliusc

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Kalispell, MT, USA
Shannon-
Looks like you got the 400-10's, but your leg mounts look to be missing the 400-09's (outer reinforcements). I don't understand how the bolt holes don't line up.
-Christian
 

MadRocketScientist

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Canterbury, New Zealand, Earth, Milky Way Galaxy.
I think there is a mistake somewhere in my CAD drawings. It seems I hadn't allowed for the gear mount sitting parallel to the skin and had drawn the holes as if the mount sat level. I will get to the bottom of it eventually and update my drawings.

I have left off the outer reinforcements (400 09) as the lower tube (400 06) is much thicker than in the plans to stop it cutting into the support bushings. After some discussion with the local builders and due to the thicker weld I don't think the additional reinforcements will be needed. Although it will be something I will be keeping a close eye on.

A few more pics of the nose gear progress. I ended up machining both tubes, the outer to save weight and a very light cut off the aluminium inner to make it a sliding fit. As is sometimes the case as soon as I was finished turning them I realized an even better option.:ponder::emb:

In the plans it mentions that the inner (401 05) can be made using 2mm wall thickness tubing. If doing this again I would use 7/8"x0.035" 4130N tube for the outer and a 7/8"x0.120"6061T6 machined to fit inside for the inner. The plans state the weight gain for the 2mm wall thickness instead of 1.5mm is around 20grams. This would only need one machining operation. and the modulus of elasticity of 6061 is close to that of 2024. (if the nose gear bends it will be next to useless even though the 2024 has a higher ultimate failure strength)

It would be so much easier if aircraft grade metric tube was readily available here.;)

Shannon.
 

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danmcgee

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Very well done Shannon great work. You are really knocking her out there. are you going to use a clear canopy for the rear portion as well or aluminum as we all have seen on other Cri Cri's?

Dan
 

Mac790

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Poznan, Poland
Very nice work Shannon,

It looks like a real airplane now:), it's a pity that we don't live closer, I would really like to see her in person. Can't wait to see the wings, and stabs completed. Have you thought about paint scheme?

Seb
 

danmcgee

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Hey Shannon were did you get your tank mold from? Also what is your idea for a oven to make your conopy's in you got my curiosity raised up here on that one. When you make your tank take lots of photos I bet I will not be the only one watching that progress with intent intreset.

Dan

Oh did you gewt your front nose gear mount fixed from the bad welds?
 

MadRocketScientist

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Canterbury, New Zealand, Earth, Milky Way Galaxy.
Lots more pieces welded, painted etc.

I see a three bladed prop, wonder where that came from:gig:, pity its only a MDF mockup at this point in the game.

Note the weld jig for the rudder pedals. The pedals only fit in them before the cable guides are welded on the sides.

Shannon.
 

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Mac790

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WOW, nice prop Shannon, are you also going to make a real one? Seems like a piece o cake, with CNC router:gig: How long it took to make?

Seb
 

MadRocketScientist

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Location
Canterbury, New Zealand, Earth, Milky Way Galaxy.
Yes I will be making real ones, thinking of doing them counter rotating. If you look closely at pics the first prop is different from the other one. I am not sure whether I will do them in wood or composite. Wood with a vacuum bagged carbon fiber wrap would be nice. Too many options:ponder:.

Takes around 35mins per blade on the CNC and possibly around 3 hours including making the prop blank. Finishing a real prop after the CNC has done its thing takes a lot longer.

The file I cut these from is pretty crude, I will get a better 3D model when I am closer to needing the real ones.

Shannon.
 
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