Alternative Rotor Materials
01-16-2005, 11:24 AM
#11
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Originally Posted by 20bPlease' date='Jan 16 2005, 12:15 AM
what do you mean if the rotors are too light the bearings are gonna take a beatng? wouldnt less weight help the bearings? and yes i know they work well.. everyone works "well" but everything can also be improved on... ughh people come on... not many people leave the "box" when it comes to building their rx-7's
the bearing needs support, it does have more load at some crankshaft angles than others.
casting new rotors seems like it would be a huge expensive and complex task, why not look into something more reasonable? like alloy side plates? thats a lot easier! or a center main bearing, it tackles the rotor "problem" from the other direction.
01-16-2005, 03:56 PM
#12
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Originally Posted by j9fd3s' date='Jan 16 2005, 01:24 PM
the bearing needs support, it does have more load at some crankshaft angles than others.
casting new rotors seems like it would be a huge expensive and complex task, why not look into something more reasonable? like alloy side plates? thats a lot easier! or a center main bearing, it tackles the rotor "problem" from the other direction.
casting new rotors seems like it would be a huge expensive and complex task, why not look into something more reasonable? like alloy side plates? thats a lot easier! or a center main bearing, it tackles the rotor "problem" from the other direction.
casting would prolly be too expensive but i could easily CNC a set. and alloy sideplates doesnt reduce rotating mass which is what im aiming for.
01-16-2005, 04:34 PM
#13
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I was under the impression you were just asking out of curiosity, If you want to reduce rotational mass flywheel, propshaft, halfshafts, wheels and tyres in reality are the cheapest and most effective route - with emphasis on the wheels and tyres because that's also unsprung mass. If you're hell bent on removing the mass the far side of the clutch, just get the flywheel taken down (professionally - flywheels are not things to take half measures with) It's a worthy cause IMO, reducing weigh is never a bad thing especially when it's rotational/unsprung.
Mark
Mark
01-17-2005, 02:44 PM
#14
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Believe it or not the weight of the rotors is beneficial to most of the people using them. Lightening things to far will make a very hard to drive vehicle unless you only do autocross. In which case they would love you.
If you have the abilities to cast and create parts with these tolerances and structure, the most effective part you could work on is the plates. There is a lot of weight in the cast iron plates that could easily be deleted with out any ill effects, and real potential benefits for anyone purchasing them.
If I had the capacity to do any casting of this nature it would be in the plates.
If you have the abilities to cast and create parts with these tolerances and structure, the most effective part you could work on is the plates. There is a lot of weight in the cast iron plates that could easily be deleted with out any ill effects, and real potential benefits for anyone purchasing them.
If I had the capacity to do any casting of this nature it would be in the plates.
01-18-2005, 06:45 PM
#15
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Originally Posted by rotarypower101' date='Jan 17 2005, 04:44 PM
Believe it or not the weight of the rotors is beneficial to most of the people using them. Lightening things to far will make a very hard to drive vehicle unless you only do autocross. In which case they would love you.
If you have the abilities to cast and create parts with these tolerances and structure, the most effective part you could work on is the plates. There is a lot of weight in the cast iron plates that could easily be deleted with out any ill effects, and real potential benefits for anyone purchasing them.
If I had the capacity to do any casting of this nature it would be in the plates.
If you have the abilities to cast and create parts with these tolerances and structure, the most effective part you could work on is the plates. There is a lot of weight in the cast iron plates that could easily be deleted with out any ill effects, and real potential benefits for anyone purchasing them.
If I had the capacity to do any casting of this nature it would be in the plates.
what plates are you talking about... photos...
01-19-2005, 01:30 AM
#16
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These are for a 20B obviously, but anyone can plainly see and understand that decreasing the amount of weight the engine has to carry around is always a benefit.
The plates are constructed of cast iron, and if you were to simply replicate them the density of cast iron is .27lbm/in^3 while aluminum is .10lbm/in^3 ,cast is 2.7 times, nearly three times as heavy for a given amount of material.
From some calculations I did a while back you can shave very close to 50 pounds off from an REW just by replacing the irons with a aluminum counterpart, which have already shown in rotary applications to be strong enough to work as well as cast iron.
One of the big things would be the ability to cast deep thick channels for porting, and the ability to use a modular replaceable setup for weak sections of the cast parts, ie. the dowel pins. And using steel inserts for the tension bolts for the front plate would allow for the front plate to be made of aluminum as well.
Spray these with some armcore C or ceramics and it would be a killer combination of light weight high wear low friction surface that I think could really give a rotary engine a modest increase in efficiency and longevity.
The plates are constructed of cast iron, and if you were to simply replicate them the density of cast iron is .27lbm/in^3 while aluminum is .10lbm/in^3 ,cast is 2.7 times, nearly three times as heavy for a given amount of material.
From some calculations I did a while back you can shave very close to 50 pounds off from an REW just by replacing the irons with a aluminum counterpart, which have already shown in rotary applications to be strong enough to work as well as cast iron.
One of the big things would be the ability to cast deep thick channels for porting, and the ability to use a modular replaceable setup for weak sections of the cast parts, ie. the dowel pins. And using steel inserts for the tension bolts for the front plate would allow for the front plate to be made of aluminum as well.
Spray these with some armcore C or ceramics and it would be a killer combination of light weight high wear low friction surface that I think could really give a rotary engine a modest increase in efficiency and longevity.
01-19-2005, 01:40 AM
#17
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Originally Posted by Mazdero' date='Jan 14 2005, 03:05 AM
I have a friend in Australia who made rotors out of aluminum. he said that the Apex seal groove would wear very fast, so he made the groove larger and put a steel insert in the groove for the Apex seal to sit in. He told me it worked awesome, but was very expensive to manufacture. I remember him telling me it has to be a certain grade of aluminum, something about expansion rates. I don't remember since this was a while back.
How low did he get them down to?
01-27-2005, 10:23 PM
#19
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Originally Posted by 20bPlease' date='Jan 18 2005, 07:45 PM
racing beat sells aluminum plates
01-30-2005, 09:44 PM
#20
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Originally Posted by CrassFC3S' date='Jan 21 2005, 02:14 PM
no. it will still have the whole drivetrain to drag with it. The only time it would really rev any faster is when it is in neutral, and even then its dragging the flywheel.
it wouldn't be enough of a difference to cause a problem, but it might be enough of a difference to help.