McLaren M20#73

Hi Andy, drop me your email address by PM thanks, can`t seem to find it. I am sorting out a road trip for late January and will call in if your around then.
Cheers
Russell
 
I've been building for 2 years now... the goal is to be running late summer which I consider doable.. a lot of stars will have to align.
Work continues on the rear suspension tower, and will require another couple of days to complete. Its the first time both rear rims have been mounted(15"x18" wide). Since having to wheel mount the 12" rotors and calipers, the inner rim halves will have to be changed as they're not large enough diameter. Will have a think on that one.
Will probably go with a MRX knife edge anti-roll bar setup.
Andrew
 

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That's looking really good Andrew. You have got through it much faster than I thought you would, a tribute to your skill. I'm going to have mine done by Christmas (even if it kills me) would cool to get both cars and Andrew Robinsons car together for a photo. I'm in body prep mode now and will have paint on it at Labour weekend. Just working through the list of small Fab and mechanical jobs that seem to be never ending. I'm in the process of making a mold to do the wind screen more like the original. Wait and see how it turns out, if you like it I could do one for you. As always, fantastic work. Cheers Leon
 
I've been building for 2 years now... the goal is to be running late summer which I consider doable.. a lot of stars will have to align.
Work continues on the rear suspension tower, and will require another couple of days to complete. Its the first time both rear rims have been mounted(15"x18" wide). Since having to wheel mount the 12" rotors and calipers, the inner rim halves will have to be changed as they're not large enough diameter. Will have a think on that one.
Will probably go with a MRX knife edge anti-roll bar setup.
Andrew
Steam roller anyone !!!
 
Hi Andy, if you look on page 29 post 568 there is a few photos of the front clip support attachments, they have the brake ducts incorporated, attached to the top link point and at the bottom on the tub. At the front the original is a cup/hook thing, I have made a drop and slide back arrangement and at the rear it will drop onto or slide back into a pin arrangement (haven't done that yet) as for the rear, it has the pins the same as original on the side pods and the back will hinge on a bracket bolted to the gear box. Yours will be quite different as it will have to suit the trans and the clip, I believe your trans will protrude through the rear panel on your car. Mine just fits inside and my trans is shorter than yours it will pin/bolt through the support pieces I glassed into the rear section of the clip, yours and mine are the same. I hope that is of some help, I will put up photos of the rear bracket when its welded up and finished. Cheers Leon
 
Leon.. Thanks for the info, let me know how your screen turns out.
The Rear suspension tower is finished. I added a latice tube arrangement that’s a little different than original but should be solid. An additional support bar was fabricated from the bell housing base to the engine to stop any flexing.
The Roll hoop is being bend. The rear stays on the original bolted to the BB intake manifold but that is not and option for this LS based motor due to the fuel injection. I will probably attach it to the rear suspension tower and have to add some crush tubes/base plate.
The ‘S1Sequential’ Load Cell/Stain gauge turned up. Looks quite nice, it’s programmed from a USB on the top, under the shift handle for lift free gear shifts. Fitted nicely on the Albins shifter.
Keeping at it... Andrew.
 

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That looks good and extremely complexed, the original is quite simple but of course is suited to the Hewland Trans. The original bolts to the side plates but mine bolts to a bracket on the top of the trans which is flat, however I do have my bolt spacing to suit the Hewland (in case I won Lotto) and my bottom mount is very simple again my trans is flat on the bottom like a Hewland. I have done a template for the screen just need to make a mold to heat and form it over. Still busy with body prep paint next weekend, YAHOO!! getting ever closer. Cheers Leon
 
The Roll Hoop has been fun and games getting Motorsport NZ Cage Homologation over the line. The main hoop footing plate has to be a 120cm2 x 3mm steel plate welded to the chassis. (I know... its aluminium), my 5mm plates didn’t conform. The diagonal has to be 1 piece 38.1 x 2.5mm welded within 100mm of the footing plate. The rear stays must be straight, no hinge mounts.The welding of the hoop must be from a RM. (MSNZ Recognised Manufacturer).these are just a few of the MSNZ Schedule A’ rules that must be adhered to. So I have to go down the Alternate design path, and get an Engineer to approve design and provide load calculations and get a RM shop to weld up structure. All just takes a bit more time and money. Working through it.
So during lock down 8 months ago I organised a 3 day, 2 nights bicycle trip on the Heaphy Track. One of the ‘Great NZ Walking tracks’, 4 bikes were strapped under the wings of a Cessna 185, and from Wellington airport flew to the Aorere valley (top of South Island) and landed in a cow padock next to the start of the track. Quite exciting.. A tough 1st day riding, some great views and memories were had, then flew back, Karamea - Wellington, all in 3 days.
..car progress slowed.
Andrew
 

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The Roll Hoop has been fun and games getting Motorsport NZ Cage Homologation over the line......So I have to go down the Alternate design path, and get an Engineer to approve design and provide load calculations....
Hi Andy,

I went the alternative design path and it was straightforward. I supplied hand-drawings to a structural engineer guy moonlighting at Gary Douglas Engineers Ltd (GDE) in Palmerston North. All I supplied was my main roll bar and backstay detail and materials specs, and he simulated deformation at design loads assuming it was robustly connected to the rest of the spaceframe. I have hinge joints. My understanding is that none of the standard fabrication details and "rules" need to be followed if you go the alternative design and have it engineered. In the end it was as easy as a standard homologation. I can dig out the details and PM you if you are interested.

Cheers, Andrew
 
Hello, Andrew, If you send me a sketch with all important information, I can trace your roll bar in the CAD and do a FEM analysis. Then you can see how something bends
 
Hi Andrew, I reread your build log last week as you had been down this path already. I sent GDE a few sketches of the rear sub frame and Roll Hoop which they are modelling this week. So its all under way.
Hans, thanks for your offer, I have it covered as per above.
Andrew.
 
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