Winter Build - 1/3rd scale Iris

OKTurbo said:

Would you feel uncomfortable with swept back fins that looked like this?
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Iris to Aerobee 350 in the blink of an eye!

I don't think you will have any problems at all with your fin mods. I'm lovin' the scale details...

AfterBurners said:

Your method of soaking the balsa with thin CA is the same method I use. It really hardens the balsa and it sands like butter after it dries. I usually do 2-3 applications.

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AfterBurners, I believe OKTurbo used penetrating epoxy on the nosecone and couplers. It is a thin version of epoxy designed to thin enough that wood will soak it up & then harden. Used for resoration work.

I have a theory on coating balsa nose cones with CA . . .

Heating the nose cone first might increase the absorption of CA, since the pores of the wood would be more open.

Dave F.

Yeah, I soaked the nose cone in Smith’s Clear Penetrating Epoxy Sealer. It’s primarily used to restore dry rot wood. Seems to have soaked in pretty good. I’m still going to cover the nose cone in a layer of fiberglass too.

I got a little quiet time after the Christmas presents were all opened.

OKTurbo said:

Yeah, I soaked the nose cone in Smith’s Clear Penetrating Epoxy Sealer. It’s primarily used to restore dry rot wood. Seems to have soaked in pretty good. I’m still going to cover the nose cone in a layer of fiberglass too.

I got a little quiet time after the Christmas presents were all opened.
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Nice.

Greg Furtman said:

AfterBurners, I believe OKTurbo used penetrating epoxy on the nosecone and couplers. It is a thin version of epoxy designed to thin enough that wood will soak it up & then harden. Used for resoration work.

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My apologies

Can't wait to see this one finished! I've been wanting to do more scale builds and this is getting me more motivated. Loving the attention to detail.

Dave
What I do is add a Magnetic apogee detector to the altimeter section and if at any time the rocket goes wrong and ends up under power and horizontal
the MAD will separate the payload section and deploy the parachute to slow the rocket down to just doing some cartwheels

bobby_hamill said:

Dave
What I do is add a Magnetic apogee detector to the altimeter section and if at any time the rocket goes wrong and ends up under power and horizontal
the MAD will separate the payload section and deploy the parachute to slow the rocket down to just doing some cartwheels

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Bobby,

I have seen MAD's used for Apogee deployment. How well does it react in a high-speed instability situation, like a shred, for example ?

Dave F.

Dave

It will separate the rocket into 2 halves instead of being streamlined, If for instance in a shred the fins will be gone and that will help it to be non stable. I was referring to if for instance say only 1 fin came off it may go horizontal in a straight line.

But if the payload section is ejected and the parachute comes out the chute may shred but you will still have something out in the air stream
to prevent the rocket from being like an arrow to just tumbling.

More like the lesser of 2 evils. I would rather have parts of a rocket that has slowed down some and tumbling horizontally than a fully intact rocket
going horizontal like a bat out of Hades

The MAD will deploy the parachute if it is at apogee or not just as long as the MAD detects that it is 90 degrees from vertical

Bobby

Bobby,

Thanks for the explanation. I have never used a MAD, personally.

Dave F.

Woah. Been a long time since I’ve updated this....ever have a project stall on ya?

Got out in the shop and Started to fiberglass the nose cone.





Now to mix up the epoxy and make it happen. I used and old busted up booster section to hold the nose one, bu you know....it looks pretty good. I like those proportions. Maybe another project.

Almost a shame to cover that awesome wood work... Great to see you back at this one!

I was wondering what happened! Glad you're on it again, I have a lot of interest in an Iris.

First round of ‘fill and sand’ is done. Lots of dust...

First try at making the fin brackets look right. Probably going to make a fixture so I can make a bunch that are all the same.

The screws are a really nice touch, that's the kind of detail that sets a rocket apart.

Ok kids, this is how we did it before laser cutters.

I committed on the motor mount. It’s glued into the body tube. I used Titebond II just to avoid an epoxy mess. The little fin mount brackets are going on now. Nosecone is looking better. My goal for it is a polished aluminum look.

Progress pics for Friday. Adding a few more scale details.


Current state of things.


And I need to get a plan on the electronics ...

Had to make some little standoffs for the rail guides so they clear all the ‘bumps’.

Man Turbo, that is looking fantastic! Brilliant work!

Thanks Mugs! I’m really going for scale on this one since we have such good documentation on the IRIS...plus it’s a simple one to build.

I’ve been working on the finish. Not a lot to show. It’s a slow process. The nosecone will be painted gloss black then the ‘Spaz Stix’ mirror chrome will go over that. Hoping for a metallic look. First time to try it.

The Spaz stix give a fairly convincing polished aluminum finish. I think it needs a little more coverage, but I ran out. Ordered another can. Next will be layout the black roll pattern. Then red fins.

OKTurbo said:

The Spaz stix give a fairly convincing polished aluminum finish. I think it needs a little more coverage, but I ran out. Ordered another can. Next will be layout the black roll pattern. Then red fins.
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That looks great!!

Can I ask where you sourced all of the tiny hardware that you used for your detail bits? I need things like that for my Zeus/Spartan project.

Mugs914 said:

Can I ask where you sourced all of the tiny hardware that you used for your detail bits? I need things like that for my Zeus/Spartan project.

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Got it all from eBay. All pretty cheap, but it came from China so delivery was slow. The challenge is to find the correct size for your scale.