Rigid collar subframe reinforcement, INTERESTING, any thoughts?
#26
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Had a chat with my CNC-buddy. He had a look at the images and asked if the collars was made in titanium when he heard the price
We will look into producing a prototype set in highgrade aluminium for a third of the price , will there be any interrest in this?
We will look into producing a prototype set in highgrade aluminium for a third of the price , will there be any interrest in this?
#28
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The "point" in theese collars, is to eliminate the space between the subframe hole edge and the bolt, and by this eliminate the possibility of subframe movement. the built in "washer" is like a copper-ring between for ex. oilpan and oiltap-bolt.
#29
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Subframe Movement and Camber
Definitely interested.
#32
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What kind of aluminum should be used? I'm going to make a set real quick and see if it does anything
Probably want an aluminum alloy such as 1100 or 3003 that is easy to anneal once machined.
You want these annealed "dead soft" so that they can function as shown in the video.
Are they re-usable? Since there forming to fit, does that mean if you ever take the subframe off again that you would need another set?
I imagine it would be like re-using fiber style gaskets. You can with proper preparation and if you are really careful on installation and removal.
In this case, perhaps apply liberal anti-seize when assembling and when removing be very careful to bring the subframe straight down off of any studs.
Probably want an aluminum alloy such as 1100 or 3003 that is easy to anneal once machined.
You want these annealed "dead soft" so that they can function as shown in the video.
Are they re-usable? Since there forming to fit, does that mean if you ever take the subframe off again that you would need another set?
I imagine it would be like re-using fiber style gaskets. You can with proper preparation and if you are really careful on installation and removal.
In this case, perhaps apply liberal anti-seize when assembling and when removing be very careful to bring the subframe straight down off of any studs.
#33
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I don't see it. It is really just a bandaid for a poorly designed joint.
The proper way to design a bolted connection in shear is to use the friction of the mating surfaces to create the strength of the joint, not the shear strength of the bolt. Basically this means that unless the connection is improperly designed in the first place, sleeving the connection is defeating the whole purpose.
The shear strength of bolt+sleeve will likely still be less than the frictional force required to move the clamped connection. Additionally, this means that you are much more likely to reach the failure point of the bolt/sleeve because a much higher percentage of the resisting force is being transferred into the bolt.
One other thing is that as mentioned by others, fabricated sheet metal unibodies are not that precise, which means that by forcing the holes to be concentric, you are likely preloading the joint to some degree.
The proper way to design a bolted connection in shear is to use the friction of the mating surfaces to create the strength of the joint, not the shear strength of the bolt. Basically this means that unless the connection is improperly designed in the first place, sleeving the connection is defeating the whole purpose.
The shear strength of bolt+sleeve will likely still be less than the frictional force required to move the clamped connection. Additionally, this means that you are much more likely to reach the failure point of the bolt/sleeve because a much higher percentage of the resisting force is being transferred into the bolt.
One other thing is that as mentioned by others, fabricated sheet metal unibodies are not that precise, which means that by forcing the holes to be concentric, you are likely preloading the joint to some degree.
#35
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Before I did that, I would mark the subframe and either do a trackday or at least toss the car around hard in a parking lot, and see if it moves. I have my doubts as to whether this is an issue for the FD at all.
Assuming that it is found to move though, yes, you could do that, or you could increase the torque on the bolt. Or, what I would do, is drive the car and let the subframe get seated where it wants to be, then weld a pin or some keystock around the edges of the mounting location to remove the possibility of movement. That way you are not overstressing the bolt, nor are you forcing the subframe into a position it may not fit, but you are still constraining it fully.
Assuming that it is found to move though, yes, you could do that, or you could increase the torque on the bolt. Or, what I would do, is drive the car and let the subframe get seated where it wants to be, then weld a pin or some keystock around the edges of the mounting location to remove the possibility of movement. That way you are not overstressing the bolt, nor are you forcing the subframe into a position it may not fit, but you are still constraining it fully.
#36
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I don't see it. It is really just a bandaid for a poorly designed joint.
The proper way to design a bolted connection in shear is to use the friction of the mating surfaces to create the strength of the joint, not the shear strength of the bolt. Basically this means that unless the connection is improperly designed in the first place, sleeving the connection is defeating the whole purpose.
The shear strength of bolt+sleeve will likely still be less than the frictional force required to move the clamped connection. Additionally, this means that you are much more likely to reach the failure point of the bolt/sleeve because a much higher percentage of the resisting force is being transferred into the bolt.
One other thing is that as mentioned by others, fabricated sheet metal unibodies are not that precise, which means that by forcing the holes to be concentric, you are likely preloading the joint to some degree.
The proper way to design a bolted connection in shear is to use the friction of the mating surfaces to create the strength of the joint, not the shear strength of the bolt. Basically this means that unless the connection is improperly designed in the first place, sleeving the connection is defeating the whole purpose.
The shear strength of bolt+sleeve will likely still be less than the frictional force required to move the clamped connection. Additionally, this means that you are much more likely to reach the failure point of the bolt/sleeve because a much higher percentage of the resisting force is being transferred into the bolt.
One other thing is that as mentioned by others, fabricated sheet metal unibodies are not that precise, which means that by forcing the holes to be concentric, you are likely preloading the joint to some degree.
#37
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Interesting concept... I just can't see spending 300+ on these parts that might cost $10 to make in mass production.. And I'm sure bolt holes are interchangeable with other cars..
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