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Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3812 Reg: 04-2006
| Not sure yet. The shaft itself was 1250grams. Need to add the bearings and housings, plus the little brackets and the additional tube (below) to support the rear bearing. I estimate the whole deal will come in at less than 3kg, so a saving of about 5kg or more. I need to weld a bar in to support the front bearing. I have been playing around with sand bending some tube I had laying around. I just buggered it up in the shed and tore through the steel. I have welded it up, and will have a look tomorrow night to see if it is salvageable. I need to sort out the wiring and switches. I hope to get it all sorted in the next two weeks. I go for surgery on that damn shoulder in October, and then I am out of action for probably 3-6 months. |
Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 753 Reg: 06-2008
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Ben Lipman wrote on Monday, September 22, 2014 - 08:45 pm:I need to weld a bar in to support the front bearing.
I will be interested to see what you do here, so please post photos. Mine will probably need something too.
Ben Lipman wrote on Monday, September 22, 2014 - 08:45 pm:I go for surgery on that damn shoulder in October, and then I am out of action for probably 3-6 months.
Oh bugger... |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3813 Reg: 04-2006
| Andrew, After reading a Formula SAE judges paper on common design faults with Formula SAE cars, one of his gripes is that a lot of cars only used a single bearing or mount to support the column. This causes the bearing to act as a pivot and allow the column to swing around. I used some 19mm (1.2mm wall thickness) that I had lying around. I filled it with sand and bent it into a U shape. The design is shamelessly stolen from the Kelly V8 Supercars, as seen on the TV coverage.
This I welded to the dash bar on the roll cage, just near where the front bearing is mounted. It is only tacked with he arc welder to test the strength at the moment. (Seems to be quite strong laterally, but needs some gussets to support it in the vertical plane - using larger OD tube would have helped). The bearing is supported between the tube by some 2mm steel cut and bent to fit.
The tube is not quite symmetrical, which annoys me. I considered going out and buying more steel to do it again, but seeing as I am trying to get it all done out of work hours (ie at night) that would have meant work stopping for a few days. At least this way people will know it is home built, LOL. |
Aaron Casey
Goo Roo NSW '94 2jz JZZ30 gttl, '93 UZZ31 track, VT, 2x Leyland Mini's
Posts: 3715 Reg: 08-2005
| Hahahahaha looking good man! Carbon dash moulds would see a few people interested me thinks haha |
Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 756 Reg: 06-2008
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Ben Lipman wrote on Wednesday, September 24, 2014 - 06:31 am:After reading a Formula SAE judges paper on common design faults with Formula SAE cars, one of his gripes is that a lot of cars only used a single bearing or mount to support the column. This causes the bearing to act as a pivot and allow the column to swing around.
Yep, mine has two as well. Front one is lower down than yours, rear one hanging off the dash bar. But we just extended the column to change my driving position, so wondering if there will now be too much flex in it. We will find out the first time out... |
Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 757 Reg: 06-2008
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Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3817 Reg: 04-2006
| I think the only movement in yours would be from the actual flex in the steel shaft. If you move the bearing closer to the wheel you may run the risk of having a large section in the middle unsupported and therefore able to flex. The paper I read defined 'tests' for various components. The steering column only sees torsional loads of 10 -15kg in SAE cars so I would estimate big heavy cars with wide tyres this would be no more than 50kg with no power steering. The other two loads are from the monkey hanging off the back of it when he gets in and out of the car(lateral), and straight down the shaft in a big frontal impact(longitudinal). The shafts will be incredibly strong along its length, possibly too strong when you think about it going through your chest. As for lateral strength, I think if you can grab the wheel and get in and out of the car, then it is strong enough. That is how I am testing mine, and why I think it needs some gusseting at the roll bar join for more strength in the vertical plane. I wish I had of explored the way your column is mounted. There is some utility to having it mounted semi permanently with U bolts/pipe clamps etc. |
Michael McKellar
TryHard NSW Mini
Posts: 133 Reg: 08-2008
| The other thing to consider is how the bodywork in front of the rollcage would deform in a frontal impact. If it moves the bottom of the column towards you, the safest thing is to have the column pivot upwards around the the rear mount. THis moves it away from you rather than allowing it to spear your chest. |
Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 758 Reg: 06-2008
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Ben Lipman wrote on Thursday, September 25, 2014 - 06:32 am:I wish I had of explored the way your column is mounted. There is some utility to having it mounted semi permanently with U bolts/pipe clamps etc.
Ben Lipman wrote on Thursday, September 25, 2014 - 06:32 am:If you move the bearing closer to the wheel you may run the risk of having a large section in the middle unsupported and therefore able to flex.
That's why I wanted to see how you did yours. I can remove the bracket from the dash bar and modify it. Not to move the bearing, but to add a third one onto the shaft. |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3818 Reg: 04-2006
| Weight reduction is ongoing. The weekends effort added up to a saving of about 8kg. Combined with the previous round of weight savings (headlights, charcoal canister etc) I have found 13.5kg. Only 86kg to go. The next targets are: door hinges - I am told they are 14kg each, so an easy 10kg saving there. Supra passenger seat - maybe 20kg. Carbon doors - given mine are fibre glass maybe 2-3kg max, but they need doing. Carbon front bumper - maybe 4-5kg if I am really frugal. SO where does the other 50kg come from? |
Blake Gloyn
Goo Roo manawatu soarer JZZ30 TT
Posts: 1205 Reg: 02-2006
| the door hinges are 7kg each. |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3819 Reg: 04-2006
| Yeah sorry mate, I meant 14kg all up. Here is the dash reinstalled. I didn't like the way the old dash was 'inside' the steering wheel. I had to change focus and look away from the track. I decided to position the Racepak where I wanted it, and cut around the stock dash pad to make it fit.
One afternoon Ill check the toe rods are exactly equal, get the car off the stands and drive it in a straight line to center the steering wheel 'boss'. Then I'll weld that into position. (it is only held on by a central bolt currently) |
Peter Nitschke
Junk Filterer South Australia UZZ30 UZZ31
Posts: 12701 Reg: 11-2004
| That dash position looks excellent. |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3820 Reg: 04-2006
| Thanks Peter. I found another 1.5kg after work today. I cut the steel sections between the headlights where the bonnet catch used to be. No bonnet catch, no need for this steel. I am retaining the high beams for the time being, so I cant remove all of it.
84.5 kg to go... |
Aaron Casey
Goo Roo NSW '94 2jz JZZ30 gttl, '93 UZZ31 track, VT, 2x Leyland Mini's
Posts: 3719 Reg: 08-2005
| Another thing maybe if you get some alloy for the strut brace... few kg there we were talking about a few weeks ago.. also might be worth checking out how much Kurts intake pipes weigh, the stock cast ones would have to be a lot heavier |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3821 Reg: 04-2006
| The quest for more lightness continues. Friday night I went up to the central coast to pick up some doors. These will become plugs for new moulds, which will then be used to make lighter, prettier carbon fibre doors. Today I started making some replacement hinges. A few sketches, some measurements and a big helping of suck it and see got me started. The first hinge did not work, but it allowed me to visualise what needed to change. The second version worked OK, so I modified it a few times and now have a hinge that works.
The old factory hinges weigh 5.4kg. I have read elsewhere they weigh 7kg, but my scales have proven otherwise.
The new hinge weighs 1.3kg. It is a bit heavier than I hoped, but 200grams lighter than I budgeted. I might need to get the hole saw out and have a go at it. 81kg to go. (car now weighs 1356kg) |
Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 760 Reg: 06-2008
| Excellent work mate. I trust we'll all get to see the engineering drawings published. Didn't need a 2-stage hinge? |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3822 Reg: 04-2006
| LOL at "engineering drawings". Some white board sketches, and cardboard cut outs, none of which represent the finished product. Basically I traced the stock hinge onto some 2mm steel sheet, drilled the holes and bolted it to the car. I then guestimated the point in space around which the doors needed to rotate to actually open and close. After a few rounds of tack weld, test, grind, cut, tack weld, test, grind, cut...I ended up with this. I'll rip it off the car tomorrow and measure it when I start the other side. |
Paul Kalie
TryHard NSW TT
Posts: 156 Reg: 02-2008
| So looking at it the doors can be removed by opening and lifting up ? if so = Awesome |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3823 Reg: 04-2006
| Yeah Paul, it was part of the 'design brief' from the owner. Should make working on the car much simpler. The chopped strand fiberglass and poly resin doors weigh a little over 10kg each. I am hoping the carbon epoxy versions are significantly lighter. I am going to take my time and modify the steel doors so the moulds are nicer. I am going to get rid of a lot of the bumps, ridges and recesses in the factory doors. These will be a race car only design with no compromises. The outside will look the same, maybe a little smoother, but the inside will be smoother. |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3824 Reg: 04-2006
| Made the second hinge today. Much easier when you know what you are making before you start. So that is a total of 8.2kg off the total. 78kg to go.
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Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3830 Reg: 04-2006
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Andrew McKellar wrote on Sunday, October 05, 2014 - 07:06 pm: I trust we'll all get to see the engineering drawings published
Ben Lipman wrote on Sunday, October 05, 2014 - 07:37 pm:LOL at "engineering drawings".
Ahem. It appears that there may end up being some technical drawings to come. As part of my rehab (shouldersurgery) I have been put onto CAD. I have spent the last couple of days playing with some of the free CAD programs.
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Andrew McKellar
DieHard NSW V8 Soarer Sports Sedan
Posts: 762 Reg: 06-2008
| Very nice. Are they actually parts, or are you just playing around? |
Clayton Carlyle
TryHard NSW v8 soarer twin turbo
Posts: 335 Reg: 04-2009
| Is this turbocad Ben? |
Ben Lipman
Goo Roo SA Soarer TT manual, plus TT track car, plus a spare shell
Posts: 3831 Reg: 04-2006
| They are parts that I am playing around with. The top pic is a mould for a fascia to replace the factory stereo, with a single din stereo and pocket for stuff. The second and third pics are a gearbox mount for the R154. The second pic takes two poly bushes in the large holes, and then bolts to the lower mount in the third pic. This is just doodling for now until I can get a factory gearbox mount to take measurements from. Then I will make myself one. When I have two arms. Clayton, this is mostly Emachineshop. I think they will give me the boot soon though as the software is free assuming you get them to make your stuff. Emachineshop is easy to use as you can easily draw a shape/line and adjust measurements in the boxes by typing it. I also have Rhino3d for 'evaluation' but find it is nowhere as easy to use as emachineshop. Is turbocad free? I would like a more permanent solution that is free and easy to use. Or if not free, something I can buy for a couple of hundred dollars, not thousands.
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