That home made sports car

On Thursday, December 19, 2019 at 4:29:23 PM UTC-5, snipped-for-privacy@whidbey.com wrote :
Hi Eric. It sounds like you've been bitten by a bug that never stops until it's eaten you up. I've been there; I have an original edition of Costi n and Phipps book, and a contemporary that I bought in 1961 -- _Sports Car Bodywork_ by Locke. Over the years I've built a near-bookshelf of bodywork, chassis, and engine sports-car and race car books.
I've helped out on two such projects by others, neither one completed. I'll suggest that it's 5 to 10 times as much work as most people, even experien ced metalworking people, think.
You probably don't want to hear this, but my suggestion is to buy a good ki t car that you like and build that. There will be plenty of work to do, for a year or more, typically. If you're really lucky, you'll find one that so meone half-completed before they gave up. Those toys have left broken marri ages behind. It's sTILL much more work than most people realize.
I've gone to great lengths to try things -- hammering aluminum, welding 413 0 tube, and so on. When I did some sports car racing in the late '60s and e arly '70s, I rebuilt two Alfa Romeo engines, and tuned Jaguars, Triumphs, h ot English Fords, and Bristols (AC Bristol cars) for my sporty-car friends. I had an excellent English mechanic for a friend and teacher. Out of colle ge I first worked for Ranger Yachts, as a fiberglass layup man. It's MUCH e asier to learn than hammering aluminum.
I raced an Alfa Romeo Giulietta Spyder, an MG Midget 1275, and I drove or o wned many others. My old college roommate still has one of the 50 Lotus 7 M k IVs that were brought into the US in 1971. I've driven it; even though it 's the most advanced chassis in the Lotus 7 series, it's still twitchy. My MG was more stable. Suspension and handling are exceedingly tricky on a scr atch-built car. That's why many of the English club-racer specials took the suspension parts wholesale from some proven car. The Triumph Herald was a favorite.
Carbs are manageable. There is a good book on tuning SU's that I used to us e. I've tuned Weber DCOEs for hopped-up engines, and sliding-throat Zeniths . Just read what the experts say. SU's, particularly, have so many combinat ions of main jets and needles that you'll be completely lost, if your engin e has even the slightest modifications, without a good book. There aren't m any "experts" left to call upon. IIRC, Clare here on the NG should be able to steer you to info sources.
Good luck. I'd love to see some beginner tackle a start-to-finish sports ca r and succeed. Something really simple, like Champion's Locost, gives the b est chance of pulling it off. Beyond that, it becomes distressingly complic ated and frustrating.
Reply to
edhuntress2
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My Allstate agent told me they would insure a Locost. That was maybe 15 years ago. NJ will allow a home-built car, and issue some kind of serial number for it, like a VIN.
Reply to
edhuntress2
Like Ferraris. I've been told by a Ferrari owner, at a concours, that his 275 GTB probably had 10 pounds of Bondo in it -- right from the factory. d8-)
Reply to
edhuntress2
If you read the Costin and Phipps book, you know that the closest thing to a true space frame was the Lotus 8. It was a failure.
Look at the early MB 300 SLR to see what kind of hoops they had to go through to make a true space frame. Or look at the frame on a Maserati Tipo 61, which was known as the "Birdcage."
A Lotus 7, Locost, etc. has no lateral stiffness (no triangulation) above the floor, in the passenger bay. To race them, they cheat like hell with the roll bar triangulation to get some stiffness in there. Otherwise, they're a Flexible Flyer.
Reply to
edhuntress2
If they had doors they would only close ONCE.
A bit like the early Dart Swinger 340. If you dropped the clutch with the door unlatched, good luck!!! The Duster/demon was moderately stiffer.
Reply to
Clare Snyder
Yeh Ed, I have been thinking about buying the frame. I can weld it, I do have the proper equipment, experience, and skill. But it may be easier to register the thing if I use an already made frame. I can always mod the fram if need be. But I really want to make the body and bolt all the stuff on. Eric
Reply to
etpm
il it's eaten you up. I've been there; I have an original edition of Co stin and Phipps book, and a contemporary that I bought in 1961 -- _Sports C ar Bodywork_ by Locke. Over the years I've built a near-bookshelf of bodywo rk, chassis, and engine sports-car and race car books.
'll suggest that it's 5 to 10 times as much work as most people, even exper ienced metalworking people, think.
kit car that you like and build that. There will be plenty of work to do, for a year or more, typically. If you're really lucky, you'll find one that someone half-completed before they gave up. Those toys have left broken ma rriages behind. It's sTILL much more work than most people realize.
4130 tube, and so on. When I did some sports car racing in the late '60s an d early '70s, I rebuilt two Alfa Romeo engines, and tuned Jaguars, Triumphs , hot English Fords, and Bristols (AC Bristol cars) for my sporty-car frien ds. I had an excellent English mechanic for a friend and teacher. Out of co llege I first worked for Ranger Yachts, as a fiberglass layup man. It's MUC H easier to learn than hammering aluminum.
r owned many others. My old college roommate still has one of the 50 Lotus 7 Mk IVs that were brought into the US in 1971. I've driven it; even though it's the most advanced chassis in the Lotus 7 series, it's still twitchy. My MG was more stable. Suspension and handling are exceedingly tricky on a scratch-built car. That's why many of the English club-racer specials took the suspension parts wholesale from some proven car. The Triumph Herald was a favorite.
use. I've tuned Weber DCOEs for hopped-up engines, and sliding-throat Zeni ths. Just read what the experts say. SU's, particularly, have so many combi nations of main jets and needles that you'll be completely lost, if your en gine has even the slightest modifications, without a good book. There aren' t many "experts" left to call upon. IIRC, Clare here on the NG should be ab le to steer you to info sources.
car and succeed. Something really simple, like Champion's Locost, gives th e best chance of pulling it off. Beyond that, it becomes distressingly comp licated and frustrating.
Once again, Eric, I wish you success. I'd love to see the completed project . Are you determined to make the body from aluminum? If so, allow yourself plenty of time to learn. One book I mentioned, _Sports Car Bodywork_, talks through making a body with just a leather sandbag and hammers. I tried it once, just to see what it was like, using a hollowed log and some 3003 alum inum. Banging out the hollows wasn't hard, but I would have needed more pra ctice or some instruction to shrink out the edges.
I think that time and patience go a long way on these projects, until you g et good at it.
Reply to
edhuntress2
...Banging out the hollows wasn't hard, but I would have needed more practice or some instruction to shrink out the edges.... Ed Huntress
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How did you try to shrink the metal?
Reply to
Jim Wilkins
I used a home-made leather-faced slapper and a dolly. It was the same dolly I used over 50 years ago on steel.
I didn't anneal, but the aluminum was already pretty soft. I have used the old trick with plain acetylene to leave a layer of soot, and then burning i t off with the torch. That anneals aluminum very well, but I wasn't getting the buckles out with the method I tried. It's supposed to work.
Reply to
edhuntress2
Making a paper pattern over the buck, cutting the aluminum to the patern, forming it over the buck allowing overlaps if required, then trimming and welding to achieve the basic shape makes the job a lot easier than working from a flat sheet and attempting to do all the shaping by stretching and shrinking. There is a limit to what you can do with an english wheel, plannishing hammer, and shrinking dies - muchless with a paddle and leather bag.
That's how we formed the nose-bowl for the Pegazair project. I "carved" a form out of pink foam, then we made the patterns, formed the aluminum with the hammer and bag, welded the panels together, and wheeled and plannished it to final shape, theun using shtinking dies put the lip around the edge (simplified version - but basically correct), We DID have to anneal the material several times, and for filler tig welding the panels together we used strips sheared off of the metal we were working. The seams dissapeared completely on the finished product.
Reply to
Clare Snyder
I wonder if that comment might explain a mates situation when he had to replace a diff in his Jeep here in the UK. Apparently no way to know whether it was a US made diff or a Italian one from the VIN number you just had to remove it and measure the fasteners. The US one used inch still but the Italian one used metric, fortunately for him it was the
shipping, customs, and VAT.
Reply to
David Billington
Still inch, even after Daimler owned them?
My 1991 Ford, made in Kentucky, is all metric. I had to buy 18mm wrenches and sockets to work on it because they aren't included in sets.
Reply to
Jim Wilkins
I'm good at hammer forming copper and silver and have also done aluminum. Shrinking soft metals isn't that hard, plus you can buy shrinker/stretchers that really make it easy to shrink. EWric
Reply to
etpm
I worked at a racing company in the early 1990s and they had the low end US made shrinker/stretchers and I was told they were acceptable on steel but they found the surface damage to soft metal such as aluminium too great so avoided their use. I mentioned to the workshop foreman that I had a UK made shrinking jaw set and brought them in and we did a back to back test and the results were like chalk and cheese, both worked but the surface damage was far less with my set, I expect they're equivalent to the high end US made ones mentioned in Fournier's book or the Swiss
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the dfsshrink files to show the jaw construction and resulting surface. Would be interesting to know how much difference the alternate grit jaws shown at TinManTech make for the results with the low end shrinkers.
Reply to
David Billington

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