Crower Rod Failure
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From: Milky Way
Re: Crower Rod Failure (earl)
If you look at this picture:
And my FEA of the stresses in a rod shown as .avi movise on this page:
http://www.mtggraphics.com/big...a.htm
Look closely for the big end distortion in movie 3 and 4. You should see that the heat stress shown in Earl's pix is where the FEA predicts the distortion.
I would say the rod distorted first, then spun the bearing.... I think that is what the heat signature shows... but I don't have the rod in my hand...
And my FEA of the stresses in a rod shown as .avi movise on this page:
http://www.mtggraphics.com/big...a.htm
Look closely for the big end distortion in movie 3 and 4. You should see that the heat stress shown in Earl's pix is where the FEA predicts the distortion.
I would say the rod distorted first, then spun the bearing.... I think that is what the heat signature shows... but I don't have the rod in my hand...
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I had a set of crowers do this same thing to me 2 years ago. I just thrashed them and went to a new company. I still have them sitting in a box somewhere, if crower is going to do something about it, which I doubt.
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From: Simi Valley, CA, USA
Re: Crower Rod Failure (earl)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl »</TD></TR><TR><TD CLASS="quote">
I'm not trying to create a bandwagon movement.</TD></TR></TABLE>
Yeah... Too bad that always happens when you post. You're just too damn reputable on H-T
Anyway, I've never heard of that many problems with Crowers. I used to always hear about problems with Eagles, which is why I went with Crower to begin with. I will swear by them until a problem arises.
Although, that $300 for a single rod is bullshit. A new set of 4 retails for $700.
I'm not trying to create a bandwagon movement.</TD></TR></TABLE>
Yeah... Too bad that always happens when you post. You're just too damn reputable on H-T
Anyway, I've never heard of that many problems with Crowers. I used to always hear about problems with Eagles, which is why I went with Crower to begin with. I will swear by them until a problem arises.
Although, that $300 for a single rod is bullshit. A new set of 4 retails for $700.
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Re: Crower Rod Failure (BigMoose)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigMoose »</TD></TR><TR><TD CLASS="quote">If you look at this picture:
And my FEA of the stresses in a rod shown as .avi movise on this page:
http://www.mtggraphics.com/big...a.htm
Look closely for the big end distortion in movie 3 and 4. You should see that the heat stress shown in Earl's pix is where the FEA predicts the distortion.
I would say the rod distorted first, then spun the bearing.... I think that is what the heat signature shows... but I don't have the rod in my hand...</TD></TR></TABLE>
What would make this rod distort first or cause it to stretch like that, considering that 600 hp is not really pushing these rods.
And my FEA of the stresses in a rod shown as .avi movise on this page:
http://www.mtggraphics.com/big...a.htm
Look closely for the big end distortion in movie 3 and 4. You should see that the heat stress shown in Earl's pix is where the FEA predicts the distortion.
I would say the rod distorted first, then spun the bearing.... I think that is what the heat signature shows... but I don't have the rod in my hand...</TD></TR></TABLE>
What would make this rod distort first or cause it to stretch like that, considering that 600 hp is not really pushing these rods.
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Re: Crower Rod Failure (BigMoose)
Wow, that is good stuff, Moose. 
It seems like the annimation shown is what would happen only on the downward intake cycle where the rod is being pulled down by the rod journal.
On the compression and the exhaust strokes/cycles (both moving upwards), the rod itself would be in compression and therefore be much stronger, correct? (It is harder to compress a piece of steel than to pull it apart.)
On the power stroke (downward), you would have the pressure pushing on top of the piston/rod, therefore cushioning the rod stress in that stroke.
So what this suggests is that on 3 out of the 4 engine cycles the rod is ok but at the top of the exhaust stroke is where all the damage takes place.
This then suggests that rods should be rated by rpms and not horsepower since the higher the rpm, the more the stress.
It also suggests that aluminum rods cannot be made bulky enough for a small bore engine to ever live for long periods at high rpms. Too much flex in aluminum compared to steel.
Does my thoughts make sense, Moose, or am I completely confused?
It seems like the annimation shown is what would happen only on the downward intake cycle where the rod is being pulled down by the rod journal.
On the compression and the exhaust strokes/cycles (both moving upwards), the rod itself would be in compression and therefore be much stronger, correct? (It is harder to compress a piece of steel than to pull it apart.)
On the power stroke (downward), you would have the pressure pushing on top of the piston/rod, therefore cushioning the rod stress in that stroke.
So what this suggests is that on 3 out of the 4 engine cycles the rod is ok but at the top of the exhaust stroke is where all the damage takes place.
This then suggests that rods should be rated by rpms and not horsepower since the higher the rpm, the more the stress.
It also suggests that aluminum rods cannot be made bulky enough for a small bore engine to ever live for long periods at high rpms. Too much flex in aluminum compared to steel.
Does my thoughts make sense, Moose, or am I completely confused?
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From: Hotrod, PA, USA
Re: Crower Rod Failure (dragline)
I bent a crower rod not to long ago. Brian from crower contacted us and asked to send the rod back for inspection. Also mentioned that they thought 800hp for the weight of the rod design was about its limits. Then offered to build me a custom heavier set for a good price. BTW the rod was hydrolocked.
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From: Milky Way
Re: Crower Rod Failure (earl)
Earl, I think you are right on target with your observations. I think RPM is killing the big end of these rods... that is one of the reasons I wanted to play with the FEA analysis.
When I did the analysis I posted, I did not have the license for the software that would allow me to split the cap and analyize a bolted joint... so the FEA is far from perfect. I also owe somany's who shared with me the basic rod solid model that I tweaked. Note the solid model is not anyone's specific rod, just a genericized shape based on what is "about" current practice.
What I was intrigued with was how well the big end distortion mimicked all the heat stress photos that I had seen to date when you loaded the rod in tension, as might be induced by high RPM stresses. I did not show the compression FEA's because they were not very interesting... basically little to no distortion. I saw absolutely no preliminary instances of buckling from compressive stress (pressure loading from combustion.)
I thought the distorted shape very interesting, because at least I, felt it was not intuitive. I was surprised by the "pinching in" up in the top half.
As for the use of an aluminum rod, I would not pass judgment until a suitable shape was similarly analyzed... It's hard to guess such a complex question.
Also note these were a quick analysis, just acouple of evenings... If one were to get serious you could put a few hundred hours into the FEA.
If one were going to track down what might be the problem, especially if previous versions were suitable, I would head in one direction -> heat treatment, alloy composition... ok, Maybe two ..
For dragline, the distortion shape is driven by the modulus of the material, the imposed stress, and the geometry. That is the beauty of FEA, if done right, it shows you how your hard metal will distort under load.
When I did the analysis I posted, I did not have the license for the software that would allow me to split the cap and analyize a bolted joint... so the FEA is far from perfect. I also owe somany's who shared with me the basic rod solid model that I tweaked. Note the solid model is not anyone's specific rod, just a genericized shape based on what is "about" current practice.
What I was intrigued with was how well the big end distortion mimicked all the heat stress photos that I had seen to date when you loaded the rod in tension, as might be induced by high RPM stresses. I did not show the compression FEA's because they were not very interesting... basically little to no distortion. I saw absolutely no preliminary instances of buckling from compressive stress (pressure loading from combustion.)
I thought the distorted shape very interesting, because at least I, felt it was not intuitive. I was surprised by the "pinching in" up in the top half.
As for the use of an aluminum rod, I would not pass judgment until a suitable shape was similarly analyzed... It's hard to guess such a complex question.
Also note these were a quick analysis, just acouple of evenings... If one were to get serious you could put a few hundred hours into the FEA.
If one were going to track down what might be the problem, especially if previous versions were suitable, I would head in one direction -> heat treatment, alloy composition... ok, Maybe two ..
For dragline, the distortion shape is driven by the modulus of the material, the imposed stress, and the geometry. That is the beauty of FEA, if done right, it shows you how your hard metal will distort under load.
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From: Irvine, CA, usa
Re: Crower Rod Failure (BigMoose)
It amazed me that the distorted shape that this Crower is in, matched the shape of your stressed rod analysis. I now feel stronger that it is a rod failure thru stress rather than detonation or some other outside factor.
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From: Milky Way
Re: Crower Rod Failure (earl)
One last thought, if the RPM is in fact causing the big end to loose integrity, they then might be "HP limited" wrt failure. If the pinching is closing up the oil clearance, the higher load (from Torque) might be "punching" thru the remaining hydrodynamic oil film... just a thought.
Glad to have helped... if in fact I did!
Glad to have helped... if in fact I did!
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From: USA
Re: Crower Rod Failure (earl)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl »</TD></TR><TR><TD CLASS="quote">This then suggests that rods should be rated by rpms and not horsepower since the higher the rpm, the more the stress.
It also suggests that aluminum rods cannot be made bulky enough for a small bore engine to ever live for long periods at high rpms. Too much flex in aluminum compared to steel.</TD></TR></TABLE>
Earl, I sound like I am hounding on you, I want to assure you that I am not, but I just cannot agree with this at all. I have had the same set of rods in Ed's car for over 2 years, aluminum BME rods and I take that motor to well over 10500 RPM!!! Small bore motor, making about 1200...
I think what people seem to forget is that detonation doesn't always rear it's ugly head in the form of physical damage to the piston. Sometimes it can work off of the spark plug as a glow plug effect, sometimes off the valve edge, and other less likely times off of the head gasket. But det is also not the only factor to cause a bearing failure. A little dirt in the oil at the right time to bind the bearing to the rod journal on the crank, a little too much heat, a little bubble in the oiling system, etc. All these are factors that can and have caused bearing failure, and all have looked similar to the pics shown above.
That FEA model that Moose drew was very interesting, but hardly accurate in my opinion, no offense to Moose! FEA programs utilize inputed vector stress levels and linear gradients of deformation based on a calculated algorithm inputed into the program for any specific material. I, myself, being from a metallurgical background, feel that the materials used in rods now days cannot stretch to the point shown in those models. If this were the case, then the pins would have definitive surface fractures on them and the body of the rod would also have definite signs of deformation, whether it be in the shape of stress cracks, surface blemishes or even an over deformation in length of the rod itself, which would also be apparent on the 3 remaining rods in that set! Also, if this much deformation is occurring, then absolute signs of the pin flex would be blatantly apparent in the piston's pin bore!!! Elongated wear starting from the inside out with evident galling of aluminum onto the pin itself, especially if this was a high RPM engine and the failure happened then, but regardless, the other remaining pistons and rods can usually tell this tale in a very accurate expression of wear, deformation and signs of failure.
But again, this is just my .02
It also suggests that aluminum rods cannot be made bulky enough for a small bore engine to ever live for long periods at high rpms. Too much flex in aluminum compared to steel.</TD></TR></TABLE>
Earl, I sound like I am hounding on you, I want to assure you that I am not, but I just cannot agree with this at all. I have had the same set of rods in Ed's car for over 2 years, aluminum BME rods and I take that motor to well over 10500 RPM!!! Small bore motor, making about 1200...
I think what people seem to forget is that detonation doesn't always rear it's ugly head in the form of physical damage to the piston. Sometimes it can work off of the spark plug as a glow plug effect, sometimes off the valve edge, and other less likely times off of the head gasket. But det is also not the only factor to cause a bearing failure. A little dirt in the oil at the right time to bind the bearing to the rod journal on the crank, a little too much heat, a little bubble in the oiling system, etc. All these are factors that can and have caused bearing failure, and all have looked similar to the pics shown above.
That FEA model that Moose drew was very interesting, but hardly accurate in my opinion, no offense to Moose! FEA programs utilize inputed vector stress levels and linear gradients of deformation based on a calculated algorithm inputed into the program for any specific material. I, myself, being from a metallurgical background, feel that the materials used in rods now days cannot stretch to the point shown in those models. If this were the case, then the pins would have definitive surface fractures on them and the body of the rod would also have definite signs of deformation, whether it be in the shape of stress cracks, surface blemishes or even an over deformation in length of the rod itself, which would also be apparent on the 3 remaining rods in that set! Also, if this much deformation is occurring, then absolute signs of the pin flex would be blatantly apparent in the piston's pin bore!!! Elongated wear starting from the inside out with evident galling of aluminum onto the pin itself, especially if this was a high RPM engine and the failure happened then, but regardless, the other remaining pistons and rods can usually tell this tale in a very accurate expression of wear, deformation and signs of failure.
But again, this is just my .02
BCICAN
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From: Cincinnati, OH
Re: Crower Rod Failure (earl)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by earl »</TD></TR><TR><TD CLASS="quote">....There was no black death on any of the pistons and no signs of detonation. The other 3 rods were perfect. Still it is hard to say..... </TD></TR></TABLE>
Earl, I have an idea of what is meant by black death...but I want to hear your definition just to make sure. Or if anyone can answer. I was going to a family thing today and I randomly thought of this post haha. Thanks.
Earl, I have an idea of what is meant by black death...but I want to hear your definition just to make sure. Or if anyone can answer. I was going to a family thing today and I randomly thought of this post haha. Thanks.
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From: Simi Valley, CA, USA
Re: Crower Rod Failure (GoldenEagleMfg.com)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by GoldenEagleMfg.com »</TD></TR><TR><TD CLASS="quote">
FEA programs utilize inputed vector stress levels and linear gradients of deformation based on a calculated algorithm inputed into the program for any specific material.</TD></TR></TABLE>
I dare you to say that again.
FEA programs utilize inputed vector stress levels and linear gradients of deformation based on a calculated algorithm inputed into the program for any specific material.</TD></TR></TABLE>
I dare you to say that again.
Thread Starter
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From: Irvine, CA, usa
Re: Crower Rod Failure (GoldenEagleMfg.com)
I think if a rod went thru one revolution at Moose's annimation it would be history. It is an exagerated example of what the rod would like to do if it could. It was just interesting that the shape of the rod matched the annimation.
I've seen a few spun rod bearings and there was much more heat discoloration than this rod showed. Just not sure. I do agree that there are many things that will cause bearing failure. The uncontrolled explosion can cause failure even in a main bearing (at least in V-8's).
That is an amazing history with those rods. I have to admit I am very prejudiced against aluminum rods from back in the days when Vennom was racing. I remember at least 3 races that they ventilated blocks with aluminum rods but I think there may have been more instances on the dyno.
I've seen a few spun rod bearings and there was much more heat discoloration than this rod showed. Just not sure. I do agree that there are many things that will cause bearing failure. The uncontrolled explosion can cause failure even in a main bearing (at least in V-8's).
That is an amazing history with those rods. I have to admit I am very prejudiced against aluminum rods from back in the days when Vennom was racing. I remember at least 3 races that they ventilated blocks with aluminum rods but I think there may have been more instances on the dyno.
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From: Irvine, CA, usa
Re: Crower Rod Failure (Dunc)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Dunc »</TD></TR><TR><TD CLASS="quote">
Earl, I have an idea of what is meant by black death...but I want to hear your definition just to make sure. Or if anyone can answer. I was going to a family thing today and I randomly thought of this post haha. Thanks.</TD></TR></TABLE>
Earl, I have an idea of what is meant by black death...but I want to hear your definition just to make sure. Or if anyone can answer. I was going to a family thing today and I randomly thought of this post haha. Thanks.</TD></TR></TABLE>
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From: Milky Way
Re: Crower Rod Failure (GoldenEagleMfg.com)
Just to note that you set a scale factor to multiply the actual deformations by to generate the .avi movie. If we showed actual deformations you would not see them... just a couple of mills.
I've got softball games tonight, but if I have time, I'll pull the deformation only plots from one of those stress runs with a scale.
I've got softball games tonight, but if I have time, I'll pull the deformation only plots from one of those stress runs with a scale.
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From: USA
Re: Crower Rod Failure (BigMoose)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigMoose »</TD></TR><TR><TD CLASS="quote">Just to note that you set a scale factor to multiply the actual deformations by to generate the .avi movie. If we showed actual deformations you would not see them... just a couple of mills.
I've got softball games tonight, but if I have time, I'll pull the deformation only plots from one of those stress runs with a scale.</TD></TR></TABLE>
I see. Moose, the FEA programs I use are similar. I plotted a crower rod, and I could get very different results using different piston weights ( inputed strain vectors for pin ) and different RPM's. My FEA only allows me to strain to the yeild point of any given material. ( including the bolts. I drew the cap and rod body seperately ) Unfortunately, I am having a hard time exporting the images from the program. ( COSMOSWorks )
And again, in my FEA, it allows me to input linear stress, linear dynamics and heat transfer. It is very easy for me to deform the rod in ANY circumstance, but then again, it did this with ANY rod I drew into it. I will repair the software to gain access to image export sometime today. I have models of Crower, Pauter, Eagle, BME aluminum and Cunningham. The results will suprise you.
I've got softball games tonight, but if I have time, I'll pull the deformation only plots from one of those stress runs with a scale.</TD></TR></TABLE>
I see. Moose, the FEA programs I use are similar. I plotted a crower rod, and I could get very different results using different piston weights ( inputed strain vectors for pin ) and different RPM's. My FEA only allows me to strain to the yeild point of any given material. ( including the bolts. I drew the cap and rod body seperately ) Unfortunately, I am having a hard time exporting the images from the program. ( COSMOSWorks )
And again, in my FEA, it allows me to input linear stress, linear dynamics and heat transfer. It is very easy for me to deform the rod in ANY circumstance, but then again, it did this with ANY rod I drew into it. I will repair the software to gain access to image export sometime today. I have models of Crower, Pauter, Eagle, BME aluminum and Cunningham. The results will suprise you.
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From: Milky Way
Re: Crower Rod Failure (GoldenEagleMfg.com)
Vince,
That's great! I sure look forward to the images. I think its a good thing to have some serious technical discussion like this. It helps to show some folks the tools that are out there, and the limits to those tools.
I agree also that I can distort and fail anyone's part with FEA, so the results are always to be suspect, and applying them is sure an "art"... There are limits in the software, limits to the analyists capability, limits just about everywhere... We (the company) uses it a lot, so I respect it in the hands of an "ace" analysist (which I openly state I am not!) ... I just "dabble" in everything.
The tools do however, give an insight to the problem that many do not have. In that regard, my good friend and ace metallurgist, who I had the pleasure of working side by side for 25 years, died suddenly last week. The loss of John's quips, and insights haunt me daily... a thing to keep in mind is, "we're all just passing thru...as we try to do what we do...and search for the truth in life."
That's great! I sure look forward to the images. I think its a good thing to have some serious technical discussion like this. It helps to show some folks the tools that are out there, and the limits to those tools.
I agree also that I can distort and fail anyone's part with FEA, so the results are always to be suspect, and applying them is sure an "art"... There are limits in the software, limits to the analyists capability, limits just about everywhere... We (the company) uses it a lot, so I respect it in the hands of an "ace" analysist (which I openly state I am not!) ... I just "dabble" in everything.
The tools do however, give an insight to the problem that many do not have. In that regard, my good friend and ace metallurgist, who I had the pleasure of working side by side for 25 years, died suddenly last week. The loss of John's quips, and insights haunt me daily... a thing to keep in mind is, "we're all just passing thru...as we try to do what we do...and search for the truth in life."
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From: USA
Re: Crower Rod Failure (BigMoose)
Dave,
I am sorry to hear about your friend. I meet people all the time that I think will forget more than I will ever learn, my father being one of those people. I too do not proclaim to be any sort of pro when it comes to FEA analysis, or anything for that matter, but I am always open minded and ready to learn. After all, how else do you learn if you don't ask questions from people who are in the " Know "
But my opinion is that FEA results are subjective at best. They do allow for a detailed insight to open design flaws, but are hardly advanced enough to allow a real world scenario that can prove a failure in a multi-dimensional stress environment.
Thanks for the great input Dave, I appreciate your experience and education. We need more real world people like you giving their experience!
Vince Tiaga
I am sorry to hear about your friend. I meet people all the time that I think will forget more than I will ever learn, my father being one of those people. I too do not proclaim to be any sort of pro when it comes to FEA analysis, or anything for that matter, but I am always open minded and ready to learn. After all, how else do you learn if you don't ask questions from people who are in the " Know "
But my opinion is that FEA results are subjective at best. They do allow for a detailed insight to open design flaws, but are hardly advanced enough to allow a real world scenario that can prove a failure in a multi-dimensional stress environment.
Thanks for the great input Dave, I appreciate your experience and education. We need more real world people like you giving their experience!
Vince Tiaga
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From: Milky Way
Re: Crower Rod Failure (GoldenEagleMfg.com)
Thanks Vince,
This is one of the good threads that I too look forward to continuing...
Let me expand a little on:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">They do allow for a detailed insight to open design flaws, but are hardly advanced enough to allow a real world scenario that can prove a failure in a multi-dimensional stress environment.</TD></TR></TABLE>
The answer to that is in the field of constitutive modeling. Sadly the models are extremely proprietary. I have been around them in my career and the results are phenominal. Each one had over 60 man years of effort into their development, ...Now cost that at $300K/manyear and you have quite a large number, to say the least... These are not the tools available to the open market. In fact the existance of the tool in the company is your market advantage...
Models I have seen can track inherent flaw growth with cyclic thermal and mechanical stress to a "T" and they start with the statistical minimum flaw that any form of NDE will find. If you can believe it, another model can predict within just a few percent of the mechanical properties of alloys without ever fabricating the alloy, from the field of atomistic modeling... The atomistic modeling will simulate the heat treatment, and suboptimize the heat/cool parameters for the alloy properties and grain size you desire out the end... Way cool stuff, just not on the open market.
But I sincerely agree with you about the capability of what is openly available. ... I wonder what a rod would have to sell for if the invested NRE analysis cost alone were $2Mil...
Regards,
Dave
This is one of the good threads that I too look forward to continuing...
Let me expand a little on:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote »</TD></TR><TR><TD CLASS="quote">They do allow for a detailed insight to open design flaws, but are hardly advanced enough to allow a real world scenario that can prove a failure in a multi-dimensional stress environment.</TD></TR></TABLE>
The answer to that is in the field of constitutive modeling. Sadly the models are extremely proprietary. I have been around them in my career and the results are phenominal. Each one had over 60 man years of effort into their development, ...Now cost that at $300K/manyear and you have quite a large number, to say the least... These are not the tools available to the open market. In fact the existance of the tool in the company is your market advantage...
Models I have seen can track inherent flaw growth with cyclic thermal and mechanical stress to a "T" and they start with the statistical minimum flaw that any form of NDE will find. If you can believe it, another model can predict within just a few percent of the mechanical properties of alloys without ever fabricating the alloy, from the field of atomistic modeling... The atomistic modeling will simulate the heat treatment, and suboptimize the heat/cool parameters for the alloy properties and grain size you desire out the end... Way cool stuff, just not on the open market.
But I sincerely agree with you about the capability of what is openly available. ... I wonder what a rod would have to sell for if the invested NRE analysis cost alone were $2Mil...
Regards,
Dave
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From: USA
Re: Crower Rod Failure (BigMoose)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BigMoose »</TD></TR><TR><TD CLASS="quote">But I sincerely agree with you about the capability of what is openly available. ... I wonder what a rod would have to sell for if the invested NRE analysis cost alone were $2Mil...
Regards,
Dave</TD></TR></TABLE>
Haha, point made! There is no possible way for a company to utilize the software and equipment you mentioned unless they were doing so for some type of multi-million dollar project or had a critical part to test before production ( something like Nasa, Hughes Missle Systems, Boeing, Airbus, Etc. )
The market tools of FEA are based on user inputed calibrations and most of their stress test are linear, which we all know is not the case in real life. Although I may seem like I am bashing FEA's, I am not. I think they are a great tool for education of mechanical, thermal and compositional properties in any given product design. That is why we purchased the program for our use here at the shop. We make mulitple products for companies like Boeing, Hughes Missle systems, the Swiss army, the US military and many others. Sometimes their designs come to us in fully detailed drawings that have been proven, sometimes they ask us to design the parts for them.
In any case, I will continue to research the different designs on the market and input them equally into a test scenario. Maybe you can do the same Moose and together we can show the highs and lows of each design based on our own tests
Regards,
Dave</TD></TR></TABLE>
Haha, point made! There is no possible way for a company to utilize the software and equipment you mentioned unless they were doing so for some type of multi-million dollar project or had a critical part to test before production ( something like Nasa, Hughes Missle Systems, Boeing, Airbus, Etc. )
The market tools of FEA are based on user inputed calibrations and most of their stress test are linear, which we all know is not the case in real life. Although I may seem like I am bashing FEA's, I am not. I think they are a great tool for education of mechanical, thermal and compositional properties in any given product design. That is why we purchased the program for our use here at the shop. We make mulitple products for companies like Boeing, Hughes Missle systems, the Swiss army, the US military and many others. Sometimes their designs come to us in fully detailed drawings that have been proven, sometimes they ask us to design the parts for them.
In any case, I will continue to research the different designs on the market and input them equally into a test scenario. Maybe you can do the same Moose and together we can show the highs and lows of each design based on our own tests
Honda-Tech Member
Joined: May 2004
Posts: 440
Likes: 1
From: Malta, Europe, BBG02
Re: Crower Rod Failure (earl)
I had E-mailed the link to this Post to Crower and Brian Crower sent me back and he told me :
There's obvious heat (discoloration) in the rod as a result of a spun rod
bearing.
Run your rods with confidence.
Thanks for your interest in Crower.
Crower Cams & Equipment Co, Inc
6180 Business Center Court
San Diego, CA 92154-5604 USA
Tel: 619-661-6477
Fax: 619-661-6466
http://www.crower.com
___________________
Guess now I could sleep better at night
There's obvious heat (discoloration) in the rod as a result of a spun rod
bearing.
Run your rods with confidence.
Thanks for your interest in Crower.
Crower Cams & Equipment Co, Inc
6180 Business Center Court
San Diego, CA 92154-5604 USA
Tel: 619-661-6477
Fax: 619-661-6466
http://www.crower.com
___________________
Guess now I could sleep better at night