Wicked Creation on VW pan stiffening.
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Re: Wicked Creation on VW pan stiffening.
On my baja I built a rear sub frame to stiffen up the back.
It is welded to the toursion housing and the frame horns in front of the axel and has removable struts at the end of the frame horns to aid it tranny R&R. The roll cage bolts to it from the inside in four places.
It is welded to the toursion housing and the frame horns in front of the axel and has removable struts at the end of the frame horns to aid it tranny R&R. The roll cage bolts to it from the inside in four places.
BRAT Motorsports #936
Bolt Center: Salt Lake City, Ut
ACE: Air Cooled Engineering, now Black Line Racing
Bolt Center: Salt Lake City, Ut
ACE: Air Cooled Engineering, now Black Line Racing
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Re: Wicked Creation on VW pan stiffening.
That is similar to what I did then removed except I used rectangular tubing. I had a 1" X 2" cross piece between the two shock towers and two down pieces to the mounts from there. You were smart and supported the cross-piece but F/G is not good enough for a secondary support for the cross tube. Also, what is good for off-road may not be good for an autocross, road racing or a drag car.
You've also disturbed the tube's shape by notching it; I would think I would want the down support to be in place more towards the end of the tranny mount. Remember, the engine is being cantilevered off the end of the mount probably w/no other supports.
I think that the German Engineers intended for a certain amount of flex in the tubes but I don't they that expected for their little cars to be used like we do. I am not sure what they did with the combat models which might be a different story.
Anyway, a bolt in 'one size fits all' design is turning out to be more difficult than I expected.. which I should have expected.
I have another idea but I am not sure if I could make it. I am still playing with eliminating the cross-tube and substituting a couple of diagonals tot he torsion house which is still up-in-the-air because on the driver's side of the car is the clutch and throttle cables to account for.
Thanks for the input BAJA-IT.
You've also disturbed the tube's shape by notching it; I would think I would want the down support to be in place more towards the end of the tranny mount. Remember, the engine is being cantilevered off the end of the mount probably w/no other supports.
I think that the German Engineers intended for a certain amount of flex in the tubes but I don't they that expected for their little cars to be used like we do. I am not sure what they did with the combat models which might be a different story.
Anyway, a bolt in 'one size fits all' design is turning out to be more difficult than I expected.. which I should have expected.
I have another idea but I am not sure if I could make it. I am still playing with eliminating the cross-tube and substituting a couple of diagonals tot he torsion house which is still up-in-the-air because on the driver's side of the car is the clutch and throttle cables to account for.
Thanks for the input BAJA-IT.
- bajaherbie
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Re: Wicked Creation on VW pan stiffening.
mine is just like baja-it's but different.
Of all the paths you take in life, make sure a few of them are dirt.
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Re: Wicked Creation on VW pan stiffening.
I don't think I want to know!
If my understanding of it is correct: stress, like electricity, likes to run as close to the outside or on the outside of a metallic object as it can. It also doesn't like to change direction very well but it can; just running in a straight line is preferred. On a rod or wire there is only one surface but on a tube there are two surfaces for travel. You whack a third of both surfaces away even though you fill it in another plain it affects the strength or torsional/twisting ability of the tube.
If my understanding of it is correct: stress, like electricity, likes to run as close to the outside or on the outside of a metallic object as it can. It also doesn't like to change direction very well but it can; just running in a straight line is preferred. On a rod or wire there is only one surface but on a tube there are two surfaces for travel. You whack a third of both surfaces away even though you fill it in another plain it affects the strength or torsional/twisting ability of the tube.
- Piledriver
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Re: Wicked Creation on VW pan stiffening.
I'm looking to add framehorns to my 73 T3 to ditch the rear crossbar and replace the nosecone mount with a midmount setup.
The only thing giving me second thoughts is thinking I may end up with a automatic on it for reliability reasons... I need ~13.5" between the rails to clear a VW automatic... Don't want to spend kilobucks on a beefed manual that in the end will never be reliable anyway.
Wondering if the Berrien buggy CrMo setup can be spread that far.
Will be making up a custom rear crosspiece and fully captured double shear mounts for mid and rear, will be combined with a 5 bar brace setup, I will probably make this one from tubing and just weld it up as I have decent welding gear now.
The only thing giving me second thoughts is thinking I may end up with a automatic on it for reliability reasons... I need ~13.5" between the rails to clear a VW automatic... Don't want to spend kilobucks on a beefed manual that in the end will never be reliable anyway.
Wondering if the Berrien buggy CrMo setup can be spread that far.
Will be making up a custom rear crosspiece and fully captured double shear mounts for mid and rear, will be combined with a 5 bar brace setup, I will probably make this one from tubing and just weld it up as I have decent welding gear now.
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: Wicked Creation on VW pan stiffening.
Morning Pile. I've always liked the design that Barrien has (I just checked and their site has been busy updating and no pix as of now. Price is just under $90 or their tubular frame horns. They now list 3684 products and doing a quick search the product names of some of them look interesting enough to keep tabs on until pix show) simple but strong looking.
I took an old picture (taken sometime in the mid 90s.) and lightened it up to see if it showed how I originally went after trying to support a water pumper; a bit of the diagonal does show.
The way some of the old buggies were built was to put an extruded section of C-channel (sometimes called a U-channel) between the frame horns that covered the flat where the body mount bolt is. The weak part of this is they had to notch the ends of the channel to sit on the frame horns so the package tray on the shortened pan bodies (aka the rear seat on longer body buggies) would nest on top of it giving some additional body support and it also gives an ersatz place for someone to add supports like BAJA-IT did; again, the weak part is the notching of the ends of the channel.
What I did was somewhat similar but a bit different. Since that area in my glass buggy is open I had free access to a big wide area; I put a piece of 1" X 2" rectangular tubing in the same area as the flat channel (I had already had the body of my blue bug off and back on so I had an idea of what could be done) but instead of laying it parallel to the ground...
I laid it with the long side laid on the diagonal part that goes up to the shock mount. From there was a 1" X 2" rectangular tube, as a diagonal, that went down to the transaxle mount ahead of the CV joint (see arrow in picture of the engine mounted). I then built my engine cage (to look as a luggage carrier on the old cars) and added some supports to make engine mount brackets. This picture was taken during the time when I had become convinced that there would not be enough air-flow to support a radiator tucked under the body or could be ducted in to the area so I was going to use it exclusively for the fuel tank.
I had also noticed that I could get some flex out of the rectangular tube; it should have been mounted 90° to the end casting but that brought on other problems so I removed the whole mess and started in another direction.
Rails/tube framed open buggies have it much easier as everything is out in the open... except for short back rails where some additional support for the engine is needed .
I'm still playing with some ideas that I haven't been able to rule out... yet. One of them retains the cross-tube or a diagonal but the mount where I wanted to locate it is going to be difficult to make.
Lee
I took an old picture (taken sometime in the mid 90s.) and lightened it up to see if it showed how I originally went after trying to support a water pumper; a bit of the diagonal does show.
The way some of the old buggies were built was to put an extruded section of C-channel (sometimes called a U-channel) between the frame horns that covered the flat where the body mount bolt is. The weak part of this is they had to notch the ends of the channel to sit on the frame horns so the package tray on the shortened pan bodies (aka the rear seat on longer body buggies) would nest on top of it giving some additional body support and it also gives an ersatz place for someone to add supports like BAJA-IT did; again, the weak part is the notching of the ends of the channel.
What I did was somewhat similar but a bit different. Since that area in my glass buggy is open I had free access to a big wide area; I put a piece of 1" X 2" rectangular tubing in the same area as the flat channel (I had already had the body of my blue bug off and back on so I had an idea of what could be done) but instead of laying it parallel to the ground...
I laid it with the long side laid on the diagonal part that goes up to the shock mount. From there was a 1" X 2" rectangular tube, as a diagonal, that went down to the transaxle mount ahead of the CV joint (see arrow in picture of the engine mounted). I then built my engine cage (to look as a luggage carrier on the old cars) and added some supports to make engine mount brackets. This picture was taken during the time when I had become convinced that there would not be enough air-flow to support a radiator tucked under the body or could be ducted in to the area so I was going to use it exclusively for the fuel tank.
I had also noticed that I could get some flex out of the rectangular tube; it should have been mounted 90° to the end casting but that brought on other problems so I removed the whole mess and started in another direction.
Rails/tube framed open buggies have it much easier as everything is out in the open... except for short back rails where some additional support for the engine is needed .
I'm still playing with some ideas that I haven't been able to rule out... yet. One of them retains the cross-tube or a diagonal but the mount where I wanted to locate it is going to be difficult to make.
Lee
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Re: Wicked Creation on VW pan stiffening.
This is pretty much what I had in the mid-90s before cutting it off. The rectangular tube was dimensionally smaller but it still did not want to sit correctly on the end casting until welded in place. The rectangular tube I used was pretty badly made as the two long legs were different in material... probably when rolled over the mandrel the seamed side got stretched somehow; I do remember it being thinner there and it soon became apparent that the stock was too thin to start with for what I wanted it to do/support.
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- Piledriver
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Re: Wicked Creation on VW pan stiffening.
Nothing beats a nice triangulated brace setup, you can make it from reasonably light material if all the loads are simply pushing or pulling.
You could probably do it all in 1" round.
I'm trying to track down the bits to build a decent tubing notcher based on the "Notch-O-Matic" http://www.chopperhandbook.com/notcher.htm
You could probably do it all in 1" round.
I'm trying to track down the bits to build a decent tubing notcher based on the "Notch-O-Matic" http://www.chopperhandbook.com/notcher.htm
Addendum to Newtons first law:
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
zero vehicles on jackstands, square gets a fresh 090 and 1911, cabby gets a blower.
EZ3.6 Vanagon after that.(mounted, needs everything finished) then Creamsicle.
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Re: Wicked Creation on VW pan stiffening.
So far I don't think there is going to be a good one-size fits all solution. Yours is probably as good as they come for all around strength but looks heavy... is it? The "Stiffy" is triangulated a bit better... in ways; it doesn't have quite the angles your design does from the shock mount to the end of the transaxle mount but it is lacking that extra support for swing axle owners. If you made a bracket from the body to support the crossbar like BAJA-IT you might get a good situation with the truss/torsion bar that the EMPI and Eyeball engineering has; glass cars need not apply I think.
I even tried a pair of brackets mounted where the pivot for the trailing arms is that might work for the Swing axle... something similar to the Mendola "Stiffy" or your design but then what might it interfere with on the driver's side of the car (information I don't have). The other problem with that is I don't want to tie anything more to the torsion bar unless there is more support for it to the pan (back to the body lift or tot he Wicked Creations support again. On an off-road toy, that is just something hanging under the car to reduce clearance.
For the cross-bar installation like yours and the Stiffy it is pretty much push/pull but the diagonal arms are more of a deflected push/pull. The two other designs are push pull on the cross-tube and pull on the torsion bar end castings.
I'm already the best way though two rolls of masking tape too.
I looked at your tube notcher but the pix was a bit small to get too much out of it. I'll get a better look at it later and spend some time reading the dialogue.
I'm batching tonight as the women in the family decided to go out and spend a birthday for one of the two grandmothers by pulling some handles. They left at three PM and still aren't back at 11:00 PM. I hope they are having a good time.
Lee
I even tried a pair of brackets mounted where the pivot for the trailing arms is that might work for the Swing axle... something similar to the Mendola "Stiffy" or your design but then what might it interfere with on the driver's side of the car (information I don't have). The other problem with that is I don't want to tie anything more to the torsion bar unless there is more support for it to the pan (back to the body lift or tot he Wicked Creations support again. On an off-road toy, that is just something hanging under the car to reduce clearance.
For the cross-bar installation like yours and the Stiffy it is pretty much push/pull but the diagonal arms are more of a deflected push/pull. The two other designs are push pull on the cross-tube and pull on the torsion bar end castings.
I'm already the best way though two rolls of masking tape too.
I looked at your tube notcher but the pix was a bit small to get too much out of it. I'll get a better look at it later and spend some time reading the dialogue.
I'm batching tonight as the women in the family decided to go out and spend a birthday for one of the two grandmothers by pulling some handles. They left at three PM and still aren't back at 11:00 PM. I hope they are having a good time.
Lee
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Re: Wicked Creation on VW pan stiffening.
There are web based notching templates work really nice. You put in your tubing size OD, and angles that the tubes meet up. It then generates a PDF that you print and wrap around the tube to be notched. Then you just follow the outline. It comes out damn near perfect (compared to just eye balling). If you are only doing a few tubes I would just go this simple route. I used my band saw for the initial material removal, then the grinder and belt sand to pretty them up.Piledriver wrote:Nothing beats a nice triangulated brace setup, you can make it from reasonably light material if all the loads are simply pushing or pulling.
You could probably do it all in 1" round.
I'm trying to track down the bits to build a decent tubing notcher based on the "Notch-O-Matic" http://www.chopperhandbook.com/notcher.htm
http://www.metalgeek.com/static/cope.pcgi
Steve
My Baja Build
My Baja Build
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Re: Wicked Creation on VW pan stiffening.
I used notching templates to do some of the notches on the back of my car, they work good.Steve Arndt wrote:There are web based notching templates work really nice. You put in your tubing size OD, and angles that the tubes meet up. It then generates a PDF that you print and wrap around the tube to be notched. Then you just follow the outline. It comes out damn near perfect (compared to just eye balling). If you are only doing a few tubes I would just go this simple route. I used my band saw for the initial material removal, then the grinder and belt sand to pretty them up.Piledriver wrote:Nothing beats a nice triangulated brace setup, you can make it from reasonably light material if all the loads are simply pushing or pulling.
You could probably do it all in 1" round.
I'm trying to track down the bits to build a decent tubing notcher based on the "Notch-O-Matic" http://www.chopperhandbook.com/notcher.htm
http://www.metalgeek.com/static/cope.pcgi
BRAT Motorsports #936
Bolt Center: Salt Lake City, Ut
ACE: Air Cooled Engineering, now Black Line Racing
Bolt Center: Salt Lake City, Ut
ACE: Air Cooled Engineering, now Black Line Racing
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Re: Wicked Creation on VW pan stiffening.
I use a HF notcher I updated by actually aligning it and re-zeroing the angle indicators, it actually works quite well, although the bushings are loose in the bores, I was going to open the holes up slightly and try and press in some thin sealed ball bearings, the seal being key, although that link you posted looks super cool I need to dig in and maybe make that a winter project
The web notchign stuff does work tho, if you only need to do on or three its good. otherwise get the HF notcher and align it, it is very good bang for the buck, it just needs to be setup properly first.
As for the stiffening, I am loving all this good info here! And yes stress is kinda like electricity, although thinking of it like water is easier for most people. While it doesn't really travel on the outside generally, it does in torsion. this is part of why a shaft with a pinhole drilled down its length can take more torque then a solid shaft of the same size. The changing direction analogy is the most important thing however. Its like water flowing down a river, the water flow is the stress (bending, torsion, stretching, whatever) and the strength of the material is the size of the river, the amount of water is the amount of force. Turning the river or putting a small obstacle in the middle (like a rock, which we will call a hole in the material) will not end well for the river banks or the smoothness of the river. even tho a small rock in the middle of large river does not shrink the size of the river all that much, like how a small hole in a good sized beam does not change the amount of material carrying the force all that much, it is the sudden change in direction of flowing water OR stress in the material as in out example, that does the real damage.
that is a terrible explination, but if you google "stress concentration" you can get some good info, I'll try and link a decent explination when I find it. Mine is more confusing than enlightening...
The web notchign stuff does work tho, if you only need to do on or three its good. otherwise get the HF notcher and align it, it is very good bang for the buck, it just needs to be setup properly first.
As for the stiffening, I am loving all this good info here! And yes stress is kinda like electricity, although thinking of it like water is easier for most people. While it doesn't really travel on the outside generally, it does in torsion. this is part of why a shaft with a pinhole drilled down its length can take more torque then a solid shaft of the same size. The changing direction analogy is the most important thing however. Its like water flowing down a river, the water flow is the stress (bending, torsion, stretching, whatever) and the strength of the material is the size of the river, the amount of water is the amount of force. Turning the river or putting a small obstacle in the middle (like a rock, which we will call a hole in the material) will not end well for the river banks or the smoothness of the river. even tho a small rock in the middle of large river does not shrink the size of the river all that much, like how a small hole in a good sized beam does not change the amount of material carrying the force all that much, it is the sudden change in direction of flowing water OR stress in the material as in out example, that does the real damage.
that is a terrible explination, but if you google "stress concentration" you can get some good info, I'll try and link a decent explination when I find it. Mine is more confusing than enlightening...
give a man a watch and he'll allways know what time it is. give him two and he can never be sure again.
Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.
Things are rarely just crazy enough to work, but they're frequently just crazy enough to fail hilariously.
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Re: Wicked Creation on VW pan stiffening.
I'm still playing around with this Kaffer bar/truss bar/torsion bar idea when I can but I now need some hard information. Can some of you take some measurement of the shocks upper head that attaches to the torsion bar. I need the diameter of the head on the outside, the thickness of the head, grommet and spacer. I know the bolt is 12mm but if anyone can give me the shank length. In case you don't know, the shank is the unthreaded part under the head down to the threads. What I am trying to do is machine a pair of mockup pieces to represent the shock's upper end/eye along with the bolt in place and the shank length is part of that that piece of the puzzle. I am pretty sure that the shock head and the bolt head (and washer?) will affect my ideas but I need to figure out how much.
Also, if you can, can you give me clearance between the shock (worse case condition would be appreciated too) and the stock lower pocket on the trailing arm with the shock installed. What I am trying to find out is if the shock can be offset on the top and still work with the stock trailing arms. I am too cheap to go out and buy a pair of cheap shocks for the one-time use (I will if I have to though) which I would not be using otherwise. I also don't want to rely on just the cheap shock dimensions as there could be differences between them and good quality shock also.
Thanks! Lee
Also, if you can, can you give me clearance between the shock (worse case condition would be appreciated too) and the stock lower pocket on the trailing arm with the shock installed. What I am trying to find out is if the shock can be offset on the top and still work with the stock trailing arms. I am too cheap to go out and buy a pair of cheap shocks for the one-time use (I will if I have to though) which I would not be using otherwise. I also don't want to rely on just the cheap shock dimensions as there could be differences between them and good quality shock also.
Thanks! Lee
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Re: Wicked Creation on VW pan stiffening.
I haven't forgotten about this but I have gotten somewhat stymied over it.
I thought I started a string on if but can't find it so:
I laid a string between the two shock tower eyes on the torsion tube end pieces and measured the angle of each of them.
The angle is ~50° to the line on each side.
I have come to one (but not my final) conclusion: while I probably like the Stiffey best it doesn't have all the connections (stiffening) on a swing axle application (2-joint) that it does on the 4-joint IRS. I am trying for a one-size-fits-all answer.
I still like Piledriver's approach but it does get tight w/the size of clevises' he uses. He does group them towards the end of the crossbar though.
I am still kind of partial to cip1's imported unit (welding needed) http://www2.cip1.com/ProductDetails.asp ... D255%2D100 An overall look: http://www.csp-shop.de/technik/pdf/deeng/20917.pdf Where I am now is something close to the CSP design but making the end piece not a weld together assembly but that may be hard to do and still keep the price down (I am not going to manufacture it and that is for darn sure. If I did I would give it a unique name... something maybe like a flopperstopper ).
One of the reasons I like the last two is the work/load join is closer to the shock head/eye on the torsion housing that everyone ends up using one way or another. Mendola's design has that extra support piece (IRS only) that does share loading which I like.
There are a couple of other designs out there that also use the shock mount bolt but the connection to the transaxle mount connects to the crossbar away from the torsion housing which can allow the cross-tube to flex (and I understand they do from talking to people about them) defeating its purpose. One design, I think, uses the bolt to thread into the crossbar which in my opinion weakens the design. You don't put shear or angle loads on threads as they are for clamping and are weak when not used correctly.
Lee
I thought I started a string on if but can't find it so:
I laid a string between the two shock tower eyes on the torsion tube end pieces and measured the angle of each of them.
The angle is ~50° to the line on each side.
I have come to one (but not my final) conclusion: while I probably like the Stiffey best it doesn't have all the connections (stiffening) on a swing axle application (2-joint) that it does on the 4-joint IRS. I am trying for a one-size-fits-all answer.
I still like Piledriver's approach but it does get tight w/the size of clevises' he uses. He does group them towards the end of the crossbar though.
I am still kind of partial to cip1's imported unit (welding needed) http://www2.cip1.com/ProductDetails.asp ... D255%2D100 An overall look: http://www.csp-shop.de/technik/pdf/deeng/20917.pdf Where I am now is something close to the CSP design but making the end piece not a weld together assembly but that may be hard to do and still keep the price down (I am not going to manufacture it and that is for darn sure. If I did I would give it a unique name... something maybe like a flopperstopper ).
One of the reasons I like the last two is the work/load join is closer to the shock head/eye on the torsion housing that everyone ends up using one way or another. Mendola's design has that extra support piece (IRS only) that does share loading which I like.
There are a couple of other designs out there that also use the shock mount bolt but the connection to the transaxle mount connects to the crossbar away from the torsion housing which can allow the cross-tube to flex (and I understand they do from talking to people about them) defeating its purpose. One design, I think, uses the bolt to thread into the crossbar which in my opinion weakens the design. You don't put shear or angle loads on threads as they are for clamping and are weak when not used correctly.
Lee
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