Nikasil Cylinders

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Vigilant1

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Well, the aluminum case is going to run higher oil temperatures, but the aluminum cylinders would likely bring head temperatures down, and you are also going to exchange weight...so it comes out as a wash to me. Basically $2k for all the aluminum.

But keep it on a magnesium case, aluminum cylinders...better cooling all around AND you realize the weight savings....
Are higher oil temperatures normally seen with the aluminum cases? Aluminum has about 50% better heat conductivity than magnesium, which ought to translate to better heat transfer from the oil to air moving past the case (and especially the sump). The same better conduction could, I suppose, lead to more addition of heat to the case from the cylinders, but if we've already added (better cooling) Nikasil cylinders, I'd expect that to be less of a problem.
The main reason to suggest the Al case is to get sturdier bearing saddles and better resistance to eventual cracking. But those problems would be way down the road under normal use (reasonable HP, reasonable CR, etc). The Mg cases work just fine for a long time under normal use, and they save weight and $$.
 

jeffwalin

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Are higher oil temperatures normally seen with the aluminum cases? Aluminum has about 50% better heat conductivity than magnesium, which ought to translate to better heat transfer from the oil to air moving past the case (and especially the sump). The same better conduction could, I suppose, lead to more addition of heat to the case from the cylinders, but if we've already added (better cooling) Nikasil cylinders, I'd expect that to be less of a problem.
The main reason to suggest the Al case is to get sturdier bearing saddles and better resistance to eventual cracking. But those problems would be way down the road under normal use (reasonable HP, reasonable CR, etc). The Mg cases work just fine for a long time under normal use, and they save weight and $$.
The car guys report increases in oil temperatures with the Al cases. I would guess you are right about the source being the cylinders, and if so then we should see improvements with Al cylinders.

I look at the Al cylinders more for resolving heat issues at the head, and think they have the added benefit of being lighter. I don't see the issues with the Mag case being as pressing an issue in reality....maybe once the head life is increased it may become something to look towards.

As far as bearing issues I would likely look to running a Type 4 center main for the stronger crank and that can be done in a Mag case. But again....not an issue that needs immediate attention like cylinder head heat.

I'm also building a Cygnet, and any weight added to the front of that thing is going in the wrong direction!!

Jeff
 

Urquiola

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Not a VW type 1, but Rotax 912 have been doing the cast cylinders and nikasil plating for a while. The cylinders are air cooled and the heads are water cooled.

The Zipper Big Bore kit for the 912 engines use LN Engineering cylinders.

I used to be a member of the Sonerai group when the Chinese cast aluminum nikasil cylinders hit the market years ago. I even bought a set to measure and play around with....

My opinion is that the issues seen with the cast aluminum nikasil cylinders were a combination of substandard material strength and assembly procedures. They were being torqued to the same values as an engine with cast iron cylinders....and the expansion of the cast aluminum was going to be much greater than cast iron for the same temperature...so they grow more. Unfortunately this created too much pressure for the cast aluminum to withstand so it permanently deformed at the case/cylinder or cylinder/head junction (or both). I had direct conversations with a fellow (I believe in Canada) that ran them for a short while, but had trouble. When he tore the engine apart he had trouble separating the cylinders from the head and case.

Some of this possibly could have been resolved with a different torque value for the heads, but that would not resolve the issues with the Chinese cast aluminum cylinder strength. I think they are junk, even for a stock street build in a car.

The LN Engineering Nickies are a completely different animal. Jake Raby has been using them for years on his street engines, and the Porsche crowd seems to like them. The alloy is stronger, plating is likely as good as you will get, and I believe they have worked out all of the issues with them. That is what you could get for $3800!

The real problem with the LN Engineering Nickies is the economics. I don't know anyone who would think that the loss of 12 or so pounds of weight and the better thermal performance (allowing maybe a slight power boost) is worth $3800. Maybe if they were half that price.....

slociviccoupe I sure would love to see you be able to bring something like that to the market, if you could!!
I had the interior of cylinders in my Citroën 652 cc, flat-tiwn engine, re-plated with Nikasil at 'Rectificadora del Valles', near Barcelona, around 200 €. Blessings +
 

BrunoTheBear

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Hi all,

I'm working on VW Type 1 engine project for my ultralight aircraft (French regulation), and was considering using Aluminum Nicasil cylinders for weight gain purposes.
Does anyone know if the QSC 92mm Aluminum Nikasil cylinder are thin wall or thick wall cylinders?
If they are thick wall, then they can be put on a 94mm bored case, leaving quite a big amount of material to prevent deformation and distortion.
Of course if they are thin wall, it's a different situation...
 

dwalker

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I have Porsche 911 steel cylinders bored and Nikasil coated and we see better temps and longer life. On my Corvair engine I will be using in my Dragonfly I will have a set of 94MM VW cylinders cut for the conversion and then Nikasil coated. Various companies I have worked for/with have used US Chrome for over 30 years.
Porsche provided aluminum and aluminum/steel lined, known as Biral cylinders from the factory. The OEM AU cylinders were originally Nikasil which gave some issues and where phased out in favor of Alusil. The steel lined cylinders are Nikasil lined.

Ideally, any cast or "billet" AU cylinder would be made from Alusil, not lined with Nikasil, but in the aftermarket that likely is not an available option.

I am actually quite shocked no one in the VW world has picked up on the the Biral cylinders for the Type1 given the proven reduction in cooling and weight.
 

Urquiola

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Hi all,

I'm working on VW Type 1 engine project for my ultralight aircraft (French regulation), and was considering using Aluminum Nicasil cylinders for weight gain purposes.
Does anyone know if the QSC 92mm Aluminum Nikasil cylinder are thin wall or thick wall cylinders?
If they are thick wall, then they can be put on a 94mm bored case, leaving quite a big amount of material to prevent deformation and distortion.
Of course if they are thin wall, it's a different situation...
Would Corvair cylinders fit? It were produced in several different dimensions, they made over 2 million of these cars. Parts easy to find. Blessings +
 

jeffwalin

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ln engineering are kind of expensive at $3800 a set for a VW flight engine. It almost doubles the build cost.

I would love a set, though....but I would be more inclined to buy a set from Hummel Engines (Scott Casler) or build my own....
 

Tipsynipper

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The QSC cylinders are steel lined, & not Nikasil. They are thin wall.
I used a set on my Nipper years ago which worked very well & are still in service at about 300 hrs. , & have another 2 sets to fit. The QC is terrible, I made 2 good sets from 12 cylinders, some poorly machined, some different lengths.
 

jeffwalin

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QSC sells full aluminum cylinders. I could not find steel lined cylinders in their products, though they must have sold them in the past if you have a set!! I believe these were the "biral" type cylinders, which are yet another option to explore...but not currently available from QSC as far as I can tell.

 

BrunoTheBear

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QSC confirmed me they were thin wall cylinders...
Weight is an important point for my VW engine project and there seem to be 12lbs difference between steel and aluminum cylinders.
That's quite big when it's on the nose side of the aircraft !!
 

jeffwalin

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QSC confirmed me they were thin wall cylinders...
Weight is an important point for my VW engine project and there seem to be 12lbs difference between steel and aluminum cylinders.
That's quite big when it's on the nose side of the aircraft !!
Yes sir, weight is a big deal on VW powered planes particularly, with our limited horsepower.

But, particularly in the case of the cast aluminum cylinders in the past, that weight savings won't do you much good if the engine isn't reliable due to those lightweight cylinders.

A better path to weight savings would be focusing EVERYWHERE on the whole plane on saving weight.

Everything that is not NEEDED in flight is impacting performance and putting more heat into your engine.

Including my big, fat, waistline!!!
 

Tipsynipper

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QSC sells full aluminum cylinders. I could not find steel lined cylinders in their products, though they must have sold them in the past if you have a set!! I believe these were the "biral" type cylinders, which are yet another option to explore...but not currently available from QSC as far as I can tell.


QSC don't know what they are selling, or are B***ing. They listed them as Nikasil, I have been talking to ebay who may have told them to change their listing, but so far have not done so. They are steel lined, as a magnet will stick to the inner wall, unless they have invented magnetic aluminium.
If you need any more proof that they don't know what they are selling have a look at:


If you do decide to deal with QSC you can do so direct, but I would strongly recommend that you go through ebay, as you have far more protection as a buyer. I would also strongly recommend that you measure them very, very carefully.

The set I bought are still in service some 10 years later, so I am not suggesting they are no good, but, they need careful installation and care.
 

BrunoTheBear

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* its 100% aluminum
* each cylinder weight around 1kg
* all dimensions seem OK so far
* visual inspection of Nikasil coating does not show any flaws (as far as I can see)

So far so good !
 

Tipsynipper

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The cylinders I have received (all previous 4, and the last 12 which I could make a 2 sets of 4 from, 4 I sent back as un-usable due to defects in the cylinder wall or wrong length) are all steel lined.....the lining is only about 0.035" thick, so it doesn't make much difference to the weight.
Make sure you measure the length of the cylinder, from top to the base where it meets the crankcase face. QSC cyls (2).JPEGIMG_2807.JPEG
 
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