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CH701 builder information


shafs64

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Hm....no slats and VGs.

Fit a Savannah stab/elevator to it (worth looking at the South African blog on doing that) and you'd just about have a Savannah VG!

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17 hours ago, Kyle Communications said:

Dont touch it...I believe its been stored outside for 10 years

What if you did a complete recovering. You could do a good inspection of the airframe once the covering was off. 

 

If the price was rock bottom, it could be a good purchase for someone who wants an "unfinished project". A real "barn find".

 

QUESTION: Who designed the aerofoil - Otis Elevators? It looks like a Clark-Y that needs Jenny Craig.

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It's an all aluminium aircraft, OME: the coverings are the aircraft. And a major concern if it's been stored outside for a long period would be possible corrosion at every point where a piece of aluminium meets another piece of aluminium....(

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17 minutes ago, IBob said:

It's an all aluminium aircraft,

OK. That would impact on the total restoration cost if you had to replace a lot of the sheeting. 

 

Not knowing anything about the construction materials, is the frame steel or aluminium? Do the construction details advise treating the aluminium to inhibit corrosion before assembly?

 

I will admit there could be problems, but I don't see them as being insurmountable if labour costs are not an issue.

 

What is the asking price for that aircraft, and how does the price compare for the kit?

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It's all aluminium, apart from a few bits of steel in the upper cabin frame and cockpit end of the controls.

I don't know what Zenith reccomend, but ICP supply a primer, to be painted on all mating surfaces. Curiously, some folk think this means on one mating surface only, but that's another story.

Mark Kyle knows a great deal by now about the work involved in dismantling and rebuilding the Savannah, which evolved out of the 701.

I'd be listening to him.

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Zenith leave it up to the builder, so it'd vary from aircraft to aircraft.  Mark alodynes a lot of his ally which would protect it even without the black goop.  A lot of 701 builders use no primer at all.  I went for the middle ground of just using a Dulux etch primer on all surfaces that are joined.

Worth noting that 701's are made of 6061-T6 which itself has corrosion resistant properties.  But it depends on where it's been left outside - dry hot climate, probably not a problem, but anywhere with rain could pose a lot of problems over 10 years.

Edited by Marty_d
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While it is well known that cleaned aluminium will soon develop a layer of aluminium oxide, which is inert, it is wise to add an extra protective coating. I remember getting a biodegradable replacement for alodine from Aviall. The product was  X-It PreKote from Fortune Chemical Company. http://pantheonchemical.com/prekote-surface-pretreatment/

 

It is a wise move to seal any material - wood, metal or synthetic - from the effects of the environment, especially where surfaces cannot be seen or accesses after construction.

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Alodine is the rolls royce of protection but it is a lot of work. The Savannah rebuild is all alodined but I wont do that on the RANS S-21. I am actually going to do the ICP thing. I havea full tin of the black goop and will get another and I will use the back stuff on all the mating surfaces.

 

I am not going to worry about priming the insides of the sheets. My experience now of several systems and also pulling 10year old aircraft apart if you do the black stuff correctly its works a treat. If you are a bit light on with the black stuff then I have seen corrosion between stringer and sheets. Done properly it works well and that black stuff even though it is water based is bloody tough .

 

So I am pretty sure my RANS will be the only one done like this. Its about 50/50 in the USA for either chromating everything inside or not doing anything with the S-21's that are being built there.

 

 

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I use a roller about 25mm wide and roll it onto the sheet and stringer then you let it dry then assemble...its a Italain product and have never been able to buy it here but we did find a product that maybe similar. I will have to find the details again

You can see the black stuff here on stringers and ribs and spars etc where aluminium mates to another piece

 

IMG_7683.thumb.jpg.fd97492fb0c381ae98fcb614002f317e.jpgIMG_6956.thumb.jpg.bed4495b4dc1d0426cf9d930556620ef.jpg

 

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OME at the start of my build I asked about the Black Stuff, which turned into a thread here, and which, like so many conversations about painting aircraft, devolved into various strongly held views with a fair bit of heat.
In the end I came away.

And I spray primed everything instead of using the Black Stuff.

 

However, like Mark, if I were doing it all again, I would use the Black Stuff: I'm sure it would be a lot less work for the same or better result, provided one had the roller (discovered by Australian builders, I believe) for applying it.

 

It's called the Black Stuff because it arrives from ICP in an unmarked can. But once upon a time the cans were marked, and somewhere back in that Black Stuff thread is what the cans used to say. As I recall, it's a water based etch primer.

Edited by IBob
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Almost none of the internal structure on my 58 year old Beech 23 Musketeer was painted. Corrosion very minimal and not much change in the 25 years I have owned it. With any aircraft purchase have a good look and talk to people that know the type.

20190724_144814.jpg

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My twopence worth! In my years as an aircraft mechanic the worst corrosion I ever saw was on ‘factory corrosion protected’ airframes! Not sure if he is on this forum but someone who owns several 

Aerospatiale Tobagos has had to scrap at least one because of severe corrosion and they are pretty much painted throughout! On my own CH701 I have only primed all mating surfaces

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On 27/03/2021 at 3:43 PM, IBob said:

OME at the start of my build I asked about the Black Stuff, which turned into a thread here, and which, like so many conversations about painting aircraft, devolved into various strongly held views with a fair bit of heat.
In the end I came away.

And I spray primed everything instead of using the Black Stuff.

 

However, like Mark, if I were doing it all again, I would use the Black Stuff: I'm sure it would be a lot less work for the same or better result, provided one had the roller (discovered by Australian builders, I believe) for applying it.

 

It's called the Black Stuff because it arrives from ICP in an unmarked can. But once upon a time the cans were marked, and somewhere back in that Black Stuff thread is what the cans used to say. As I recall, it's a water based etch primer.

A number of Savannah builders also refer to it as "black goop".

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On 27/03/2021 at 2:53 PM, Kyle Communications said:

Alodine is the rolls royce of protection but it is a lot of work. The Savannah rebuild is all alodined but I wont do that on the RANS S-21. I am actually going to do the ICP thing. I havea full tin of the black goop and will get another and I will use the back stuff on all the mating surfaces.

 

I am not going to worry about priming the insides of the sheets. My experience now of several systems and also pulling 10year old aircraft apart if you do the black stuff correctly its works a treat. If you are a bit light on with the black stuff then I have seen corrosion between stringer and sheets. Done properly it works well and that black stuff even though it is water based is bloody tough .

 

So I am pretty sure my RANS will be the only one done like this. Its about 50/50 in the USA for either chromating everything inside or not doing anything with the S-21's that are being built there.

 

 

I am using a product made by Cortec. It is a US-manufactured water-based primer that is applied very thinly. Many North American Zenith aircraft builders use this product. Here is a short description of the product: https://www.ecorrsystems.com/store/p/4709-Cortec-VpCI-373-High-Performance-Coating-5-Gal.aspx 

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