Rotary Car Club - Tegheim - Home made 4 rotor Wolvo 142

Rotary Car Club (https://rotarycarclub.com/index.php)

- Show your rotary car build up. (https://rotarycarclub.com/forumdisplay.php?f=66)

- - Tegheim - Home made 4 rotor Wolvo 142 (https://rotarycarclub.com/showthread.php?t=13475)

what software is this again, I want it.

Investment casting to make those side plates?

No, Me and Gustav will try to do them billet. Havn't desided which material, and the design are only rough. We will work alot more on them before cutting.

First of all we shall try to make the Rotors.

What kind of lathe is that?

2axis Femco with 8, or 10" spindle I think.
Fanuc system.

Well, make sure to keep all of your programming when you're done so you can make more... I might start saving up to buy one from you lol.

In all this CAD, theory-crap and so on, I have done some backgrounds for my motivation :)

http://i815.photobucket.com/albums/z...11920x1200.jpg
http://i815.photobucket.com/albums/z...r1920x1200.jpg
http://i815.photobucket.com/albums/z...x1200-gold.jpg

Just because :)

Good combustion chamber sealing is always an issue with Wankels, so I hope you haven't made it worse by making the rotors and side plates multi-piece.
Very ambitious. Best of luck

It might be worse, but we have an idea.
We try this way, and if it's not working. Let's do it again :)

http://i815.photobucket.com/albums/z...00-brushed.jpg

As a fellow machinist and race piston engine builder why make a steel rotor when you can buy iron ones i would think if you are going to go this route use Titanium and save the weight ( half the weight of steel and all most the same strength ) or Is it to say it can be done.

The titanium would probably crack, it's too brittle.

well seeing how titanium is used as compressor blades in turbine engines.
The SR71 Blackbird is 95%+ titanium seeing any where from 500 to 3000+ degrees F at mach 3+
It's used as intake and exhaust valves in all forms of race engines, head studs for Top fuel engines at 8000 hp.
I question brittle. Figuring out the expansion rate for proper clearances at operating temps mint be a little tough.
Machining it's a bitch and aircraft quality billet is pricey.

Given how much I see it crack on aircraft firewalls, I wouldn't trust the apex seal groves, that's just me though

Plus, isnt titanium insanely expensive when compared to steel/iron?

Quote:

Given how much I see it crack on aircraft firewalls

I would say that an apple to orange comparison of a sheet metal fire wall of 0 too thin sheet titanium vs a copy thickness of a cast rotor thickness ( most people try to run titanium as thin as possible instead of the same size as the original Steel part trying to maximize the weight saving)

As an A&P in the US, aircraft firewall in the US is stainless steel per FAA. reg. non military

Quote:

Plus, isn't titanium insanely expensive when compared to steel/iron?

which is why I asked why make a steel rotor when you can buy iron ones I would think if you are going to go this route use Titanium and save the weight ( half the weight of steel and all most the same strength ) or Is it to say it can be done.

But it was just a question to see the thinking behind the route taken.

Yep, its a bitch to work with. And if you question brittle get some and try and bend it, needs a much bigger bend radius then stainless. It has it's applications no doubt. Studs and valves are a much different application to an actual rotor.

The main idea was to SAVE money doing them myself and get the other forefits along with it.
A used Rotor today are about 200USD, the material-cost only for a new one in billet-steel is about 100-110USD. And the work I do by my self.

I can understand that thinking.

With over 20 years of machining a lot of it for high end race teams and programs I tend to not look at the dollar amount but what is the advantage gained from something. I have been told buy people that know me that my out look is skued from the work that I have been involved with over the years.

Hope it works out
Good Luck :icon_tup:

We have done awsome progress this weekend. But we will not show it yet :)

im pretty sure turbine blades are a titanium alloy, specifically titanium scandium

Quote:

Originally Posted by Tegheim (Post 172576)

We have done awsome progress this weekend. But we will not show it yet :)

:D
http://t2.gstatic.com/images?q=tbn:A...I0AYpRtmod1NOf

I just ran into this thread...

First, welcome to RCC!

Second, I will be following this thread :)

Quote:

Originally Posted by Gravity Fed (Post 172577)

im pretty sure turbine blades are a titanium alloy, specifically titanium scandium

Compressor components are made from titanium-based alloys. I know Ti 6-4 is used quite a bit in blades, disks, etc.

What's a typical rotary EGT? I'm thinking all the titanium alloys I'm familiar with would not stand up to rotary combustion chamber temperatures and gases for very long. Titanium is poor in high-temperature oxidation and corrosion. Almost all modern-day turbine components (at least in the industry I work) are nickel-based. Inconels, Hastelloy, Waspalloy and other materials I can't name.

Quote:

What's a typical rotary EGT? I'm thinking all the titanium alloys I'm familiar with would not stand up to rotary combustion chamber temperatures and gases for very long. Titanium is poor in high-temperature oxidation and corrosion. Almost all modern-day turbine components (at least in the industry I work) are nickel-based. Inconels, Hastelloy, Waspalloy and other materials I can't name.
__________________

That I would agree with that on a modern-day turbine components but you also have to remember that modern-day turbines are cooled only by extra air being forced through the insides of the blades so the actual metal temp on a modern-day turbine components is a lot higher than the actual metal temp of a rotor witch is cooled on each rotor face by an intake charge of air and fuel and the internal side of the rotor has engine oil cooling it there by making the rotor more like a piston than a turbine component ( the turbine components never see a cool down cycle once its up and running )

std egt for a race rotary are around 1600 to 2000 deg F
piston race engine 1400 to 1700 deg F pending on tune and application

there are coatings that can be aplyied to the rotor for high-temperature oxidation and corrosion if that would be a problem

Quote:

Originally Posted by rgould (Post 172621)

No need to explain to me; I design turbine stators (we call 'em nozzles) for a living :) We actually use compressor bypass air to cool turbine components the "cooled" air is actually north of 1000F, typically.

Quote:

Originally Posted by rgould (Post 172621)

std egt for a race rotary are around 1600 to 2000 deg F
piston race engine 1400 to 1700 deg F pending on tune and application

That isn't as bad as I thought but still too high for Ti. From what I've seen 1000F is about the limit. In the turbine actual metal temperatures can get above 2000F, which is getting out of range for most traditional nickel-based alloys and then you've got to start getting into directionally solidified and single-crystal alloys with protective coatings...

Quote:

Originally Posted by rgould (Post 172621)

there are coatings that can be aplyied to the rotor for high-temperature oxidation and corrosion if that would be a problem

I'm familiar with your typical TBC's and environmental coatings on turbine components but not in compressors. In the aviation world compressor blades typically are bare Ti or have some kind of anti-abrasion coating.

Sorry to get OT but this is a good discussion.

http://www.kmhkreations.net/wp-conte...ollar-sign.jpg

I support the cheapness. It's cutting weight and costs less than a used rotor. Win/win.

[QUOTE]Default
Quote:
Originally Posted by rgould View Post
That I would agree with that on a modern-day turbine components but you also have to remember that modern-day turbines are cooled only by extra air being forced through the insides of the blades so the actual metal temp on a modern-day turbine components is a lot higher than the actual metal temp of a rotor witch is cooled on each rotor face by an intake charge of air and fuel and the internal side of the rotor has engine oil cooling it there by making the rotor more like a piston than a turbine component ( the turbine components never see a cool down cycle once its up and running )
No need to explain to me; I design turbine stators (we call 'em nozzles) for a living We actually use compressor bypass air to cool turbine components the "cooled" air is actually north of 1000F, typically.
Yes the rotary runs hotter than a pistion engine with its EGT temps But it is still a water and oil cooled engine witch still goverend bt some constancs

Quote:
Originally Posted by rgould View Post
std egt for a race rotary are around 1600 to 2000 deg F
piston race engine 1400 to 1700 deg F pending on tune and application
That isn't as bad as I thought but still too high for Ti. From what I've seen 1000F is about the limit. In the turbine actual metal temperatures can get above 2000F, which is getting out of range for most traditional nickel-based alloys and then you've got to start getting into directionally solidified and single-crystal alloys with protective coatings...

Quote:
Originally Posted by rgould View Post
there are coatings that can be aplyied to the rotor for high-temperature oxidation and corrosion if that would be a problem
I'm familiar with your typical TBC's and environmental coatings on turbine components but not in compressors. In the aviation world compressor blades typically are bare Ti or have some kind of anti-abrasion coating.

Sorry to get OT but this is a good discussion.

Was not trying to o fend by explaining the turbin cooling. You never realy know the person background but it also lets outher people know what we are talking about
I would say that the running temp of a rotor would be less than 500 deg F if it's that high. The Apex spring, side seai springs and corner butten springs would not be able to keep there strengh at temps higher than that. Another point would be that a rotor beinging hotter than that the oil on the inside would want to cristlize due to the heat. Also the rubber oil control seai would be more likely to fail as well.

An alum piston melts at around 1200 deg F yet a race engine see EGT of 1400 to 1700 deg F and the piston does not melt if tuned correct thanks to the water in the block and the oil in the sump keeping operating temp in a range of 180 to 230 deg F for both water and oil. The same is true of the rotary yes the EGT is higher and the parts are hotter but they still operate in a range of 180 to 230 deg F for both water and oil.

But it's good to have this discussion

Everything goes according to plan, but everything has its time:)
Meanwhile, the graphic card goes hot in the computer.
Is updating my drawings on the chassis and so on. And when inspiration is short, so make it a nice rendering, so you will be happy again:)

http://i815.photobucket.com/albums/z...s/Frame-03.jpg
http://i815.photobucket.com/albums/z...ssembly-01.jpg
http://i815.photobucket.com/albums/z...s/Frame-04.jpg

Amazing project! Good luck!!

1-4-2-3? firing order?

1-3-2-4, maybe I done it wrong in the movie? :P