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Richard O'Clery · 10-06-05, 10:15 AM

Hi Russ

I think what you have achieved to date, and the way you are going about it, is exemplary! I can't wait to see some more updates.

Can I ask about your rear uprights? Are you looking to fabricate, cast, or machine from billet?

If either of the latter two, what alloy are you planning to use?

Yes, I am being entirely subversive with these questions - I am trying to decide how best to manufacture the uprights for my own project. There are pros and cons with each and I am trying find the path of least resistance!

I'm currently favouring machining from billet, because I can have my pattern 3D scanned, imported to CAD and then milled from alloy by a local shop. The CAD can mirror it so the left and right side units can have different calliper brackets for each side (ie handbrake calliper vs main calliper), and in my case, can pickup the rear suspension pushrod behind the driveshaft on either side.

For casting, you'd have to make a pattern with attention to draft angles and shrinkage, and would have to liaise with both the foundry and the machining engineers. By the time you've reached an understanding with one, the other will find something to gripe about. I am convinced there are many layers of complexity with this approach (unless you have your own foundry - I ended up blowing chunks out of my concrete path trying this; something about leaked molten aluminium instantly boiling the water bonded in the concrete matrix - and having your own machine shop. I started to make a CNC machine, but didn't finish it because my casting aluminium ended up with too much concrete in it!)

I don't have anything against fabrication except for weight if steel, accuracy due to welding induced distortion, that it may not be pretty to look at, and can be inefficient if you want to build more than a pair or two.

I'd be really keen to hear your point of view, and from anyone else who has given consideration to all this. It's one of the many things that regularly wakes me up at about 4.19am and doesn't let me get back to sleep. Maybe I'm taking it all too seriously, but lack of sleep could be clouding my judgement...

Thanks
Richard

PS The concrete literally blew 8' into the air! The sparks from the burning electrical equipment were pretty though...

10-06-05, 10:15 AM	#22 (permalink)
Richard O'Clery roclery 3 Tenths Join Date: Jan 2005 Location: Perth, Western Australia Posts: 359 Rep Power: 7	Re: Kiwi scratchbuilt Hi Russ I think what you have achieved to date, and the way you are going about it, is exemplary! I can't wait to see some more updates. Can I ask about your rear uprights? Are you looking to fabricate, cast, or machine from billet? If either of the latter two, what alloy are you planning to use? Yes, I am being entirely subversive with these questions - I am trying to decide how best to manufacture the uprights for my own project. There are pros and cons with each and I am trying find the path of least resistance! I'm currently favouring machining from billet, because I can have my pattern 3D scanned, imported to CAD and then milled from alloy by a local shop. The CAD can mirror it so the left and right side units can have different calliper brackets for each side (ie handbrake calliper vs main calliper), and in my case, can pickup the rear suspension pushrod behind the driveshaft on either side. For casting, you'd have to make a pattern with attention to draft angles and shrinkage, and would have to liaise with both the foundry and the machining engineers. By the time you've reached an understanding with one, the other will find something to gripe about. I am convinced there are many layers of complexity with this approach (unless you have your own foundry - I ended up blowing chunks out of my concrete path trying this; something about leaked molten aluminium instantly boiling the water bonded in the concrete matrix - and having your own machine shop. I started to make a CNC machine, but didn't finish it because my casting aluminium ended up with too much concrete in it!) I don't have anything against fabrication except for weight if steel, accuracy due to welding induced distortion, that it may not be pretty to look at, and can be inefficient if you want to build more than a pair or two. I'd be really keen to hear your point of view, and from anyone else who has given consideration to all this. It's one of the many things that regularly wakes me up at about 4.19am and doesn't let me get back to sleep. Maybe I'm taking it all too seriously, but lack of sleep could be clouding my judgement... Thanks Richard PS The concrete literally blew 8' into the air! The sparks from the burning electrical equipment were pretty though...