Wanted to take a moment to introduce a new jack stand for our cars...
10-26-2016, 01:16 PM
#33
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10-26-2016, 01:38 PM
#34
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Thank you very much!
I appreciate you sharing your thoughts on the pins as well, as we've had some concerns expressed to us about how weak they appear to be.
Those current pins are 1/4" steel and each is in double sheer and capable of sustaining up to 19Kn (1.9 metric tons of force per pin). Each pin will only need to bear half the weight of whatever each stand is supporting, so you would have to load 4 metric tons on EACH stand before you approach pin failure. Considering that the stands are rated to 2 tons/pair, that gives you a safety factor of 4 for each pin.
I appreciate you sharing your thoughts on the pins as well, as we've had some concerns expressed to us about how weak they appear to be.
Those current pins are 1/4" steel and each is in double sheer and capable of sustaining up to 19Kn (1.9 metric tons of force per pin). Each pin will only need to bear half the weight of whatever each stand is supporting, so you would have to load 4 metric tons on EACH stand before you approach pin failure. Considering that the stands are rated to 2 tons/pair, that gives you a safety factor of 4 for each pin.
10-26-2016, 02:38 PM
#35
Thank you very much!
I appreciate you sharing your thoughts on the pins as well, as we've had some concerns expressed to us about how weak they appear to be.
Those current pins are 1/4" steel and each is in double sheer and capable of sustaining up to 19Kn (1.9 metric tons of force per pin). Each pin will only need to bear half the weight of whatever each stand is supporting, so you would have to load 4 metric tons on EACH stand before you approach pin failure. Considering that the stands are rated to 2 tons/pair, that gives you a safety factor of 4 for each pin.
Still, we want the stands to appear every bit as strong as they are, so we will most likely go with larger diameter pins in the production model.
Thanks again!
I appreciate you sharing your thoughts on the pins as well, as we've had some concerns expressed to us about how weak they appear to be.
Those current pins are 1/4" steel and each is in double sheer and capable of sustaining up to 19Kn (1.9 metric tons of force per pin). Each pin will only need to bear half the weight of whatever each stand is supporting, so you would have to load 4 metric tons on EACH stand before you approach pin failure. Considering that the stands are rated to 2 tons/pair, that gives you a safety factor of 4 for each pin.
Still, we want the stands to appear every bit as strong as they are, so we will most likely go with larger diameter pins in the production model.
Thanks again!
10-26-2016, 02:48 PM
#36
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Not even close. Are you sure it's a 993 you own? You seem pretty friendly and reasonable. Here in the 996 forum, we envision that most of the lawnmower engined/"It's not a real 911 if it's watercooled" owners are more like this:
BTW, I concur with the redundant pin comment. All that weight being held up by one pin manufactured who knows where with me laying underneath the car? Makes me a little nervous, especially if I'm using them to work on a much heavier vehicle.
BTW, I concur with the redundant pin comment. All that weight being held up by one pin manufactured who knows where with me laying underneath the car? Makes me a little nervous, especially if I'm using them to work on a much heavier vehicle.
10-26-2016, 03:05 PM
#38
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It looks like you have some mech engineering talent doing your design verification. Would suggest you do some actual tests under both static and dynamic(drop test) with the rig. I also suggest you test until failure and see how the product fails. Some times things break in ways we never considered like the windows blowing out of the Comet pressurized aircraft back in the 50s. (BTW, the 'n' is for Newton in SI and should be cap; '19KN')
As a sidenote regarding just the prototype, during testing a professional mechanic accidentally let the jack slip and dropped a Ford F350 (the heavy end) with the stand in place, and we were expecting it to flatten. Incredibly the protoype held without any visual signs of failure. Needless to say we disccarded that prototype anyway just to be safe, but rest assured the actual production model will be tested thoroughly and rated appropriately.
Thanks again!
10-26-2016, 03:15 PM
#39
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I'm not a mechanical engineer nor a physicist, but I do know that when something is "dropped" from a distance, the increase in load is not linear. Folks *are* going to drop their cars onto these stands, regardless of what you state in your instructions. Even from 3-4", I'm thinking that the load will be greater than 8,000 lbs. Not bashing your design. Just need to really pound the snot of them during development to ensure that you've addressed folks' subconscious concerns.
Agreed completely, and though we've both deliberately, and accidentally tested the prototypes as mentioned just above, the production version will be run through the rigors with our intent do destroy several of them to test their true limits and to ensure consistency in manufacturing quality. We're pretty obsessive over here which is probably evident in our design, with safety being the utmost concern, and we want to be able to sleep at night knowing we've engineered a solid margin of safety into the stands.
Just another thing I wanted to mention, we also tested the design on uneven surfaces under load, and though that is outside of recommended use for any jack stand, we felt it necessary to engineer a large safety margin in that respect as well.
Again, the production version will be tested to even greater extremes. You're going to receive one of the most thoroughly tested jackstands on the planet.
Thanks again!
Last edited by gyrfalcon; 10-26-2016 at 04:46 PM.
10-26-2016, 03:15 PM
#41
Race Director
Designing by committee is guaranteed to double your costs and push your ship date back at least 3 years. 
Looking forward to seeing this product for sale. Once it's for sale and I acquire a pair (of jackstands, Gnat), I'll try very hard not to drop my 911 on it from a height exceeding 4 inches, even though I've never dropped a car onto a jack stand in the 30+ years I've been old enough to work on cars with jack stands.
Looking forward to seeing this product for sale. Once it's for sale and I acquire a pair (of jackstands, Gnat), I'll try very hard not to drop my 911 on it from a height exceeding 4 inches, even though I've never dropped a car onto a jack stand in the 30+ years I've been old enough to work on cars with jack stands.
Last edited by 5CHN3LL; 10-26-2016 at 03:46 PM.
10-26-2016, 03:26 PM
#42
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Not even close. Are you sure it's a 993 you own? You seem pretty friendly and reasonable. Here in the 996 forum, we envision that most of the lawnmower engined/"It's not a real 911 if it's watercooled" owners are more like this:
https://www.youtube.com/watch?v=GgP4rEL8rSs
BTW, I concur with the redundant pin comment. All that weight being held up by one pin manufactured who knows where with me laying underneath the car? Makes me a little nervous, especially if I'm using them to work on a much heavier vehicle.
https://www.youtube.com/watch?v=GgP4rEL8rSs
BTW, I concur with the redundant pin comment. All that weight being held up by one pin manufactured who knows where with me laying underneath the car? Makes me a little nervous, especially if I'm using them to work on a much heavier vehicle.
Noted regarding the pins, and thanks to you as well for sharing that concern. That will be remedied in the production version.
10-26-2016, 03:37 PM
#43
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Designing by committee is guaranteed to double your costs and push your ship back date at least 3 years.
Looking forward to seeing this product for sale. Once it's for sale and I acquire a pair (of jackstands, Gnat), I'll try very hard not to drop my 911 on it from a height exceeding 4 inches, even though I've never dropped a car onto a jack stand in the 30+ years I've been old enough to work on cars with jack stands.
Looking forward to seeing this product for sale. Once it's for sale and I acquire a pair (of jackstands, Gnat), I'll try very hard not to drop my 911 on it from a height exceeding 4 inches, even though I've never dropped a car onto a jack stand in the 30+ years I've been old enough to work on cars with jack stands.
Don't know if we can do another 3 years of designing and testing these things with over 3 under our belts already lol. Much appreciated, and I'm looking forward to finally getting them out there!
10-26-2016, 04:12 PM
#44
Racer
For those with lowered suspensions such as H&R springs, the use of a low profile jack will be required and even then, it could be that a pre-wheel jacking as you described above, might still be required.
Certainly not a show-stopper, but a hindrance!
Great idea by the way!
Certainly not a show-stopper, but a hindrance!
Great idea by the way!
10-26-2016, 04:34 PM
#45
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For those with lowered suspensions such as H&R springs, the use of a low profile jack will be required and even then, it could be that a pre-wheel jacking as you described above, might still be required.
Certainly not a show-stopper, but a hindrance!
Great idea by the way!
Certainly not a show-stopper, but a hindrance!
Great idea by the way!
Thanks so much for the feedback and the compliment!