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1932 Studebaker Indy car build


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I'm in the middle of building a replica of a 1932 Studebaker Indy car. There was a prototype in 1931 (Hunt-Jenkins Special #37) and four more factory-sponsored cars in 1932. Most of them still exist, in one form or another. One (#22) is in the Indy Speedway Museum.

I had a frame made by Charlie Glick in Paris, IL. He did a very good job copying the chassis of the car in the Indy Museum, but there are a few niggling details that I need to adjust. I've been drawing the car in 3D CAD to get the parts placement right. This week, I discovered, several years after getting the chassis, that rear frame end is about 7 inches low compared to the original cars. The photo of #22 below shows the rear spring shackle eye at about the same height as the top of the frame rail. The other cars look about the same.

Here's a plan I am thinking about: I can live with moving the rear spring shackle eye up about 3 inches or so, don't need all 7 inches. However, any change at all involves cutting the frame about where the kickup is highest over the rear axle. The chassis is basically a "C-section" there about 4.6" high with 2" deep flanges top and bottom. 1/8th inch thick steel. I think I can cut a pie slice out of the chassis rails about .6" wide at the top flange and narrowing to a point at the bottom flange, but leaving the bottom flange uncut to keep things aligned. Then I can rotate the back 20 inches or so of the frame upward about 7.5 degrees and re-weld it. I can bevel the cut edges, weld on both sides, grind it smooth, then weld on a 1/8"-1/4" thick gusset or fish plate on the back side of each rail where it won't show.

Has anyone cut and re-welded a chassis like this? I don't like butt welds for this but I don't see any other choices, and an overlapping gusset plate should restore the stiffness. The rails are mild steel, not high strength alloy. They make stretch limos and re-weld the frames, but usually the frame rails don't show - mine do, so I can't gusset both sides or box the rails. Any suggestions?

More pictures and info about the project on my web site at http://www.studegarage.com.

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What if you had someone crawl under one of the existing cars and make you a template, then you would have a better reference of where you want to go. Then you could draw the correct version like you have done with the existing. With drawings in hand, you might consult some highly regarded frame shops and perhaps Mr. Glick. Though I believe your repair will be in compression while static, the flanges might be in various load conditions while driving. The cut upper flange makes me wonder a bit but I'm no engineer...that's why I suggest talking to a pro. The other thing is, would you be happy in the end with only moving the frame back part way? With my ballpark eye, it looks to me that your rear wheel would be almost 2" lower with the 3" adjustment vs going the full 7". Okay I'm done here...really want to see this

car finished.

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Your frame builder looks to have done a very nice job, too bad the dimensions weren't exactly right the first time around. I agree with the above 2 posts, a butt weld with interior gusseting should work fine. If you are concerned about the strength maybe a couple bolts through the plates before you weld them if you don't mind the heads being exposed. I also think if you have to cut the frame anyway, you may as well get as close to possible to the original dimensions. If you aren't happy with the 3 inch lift, it will be a lot more work to change it after you start making body panels. I've seen grain trucks built on stretched semi tractors this way and they haul a lot more weight than your car will ever see.

Edited by whtbaron (see edit history)
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I agree with your detail drawing however I would remove a section of the top flange at least 2 inches long on each side of your cut and replace it with a new, one piece section of flange so you do not have a continuous weld on the side and top of the frame. JMO

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Looking at the photo of the maroon #22 car, the rear spring eye is much higher than the front eye. This would be the result if I bring the rear up a full 7 inches. I thought that best performance occurs when the spring eyes are at the same height, but I am very open to opinions on this. Bringing my current rear spring eye up about 3.8 inches would level the spring eyes and bring the chassis rails level when the car is loaded with 2 passengers and gas. The front springs will be very stiff and the rear ones much softer. This should produce good roll resistance and good steering, though a very stiff ride, especially with bronze spring bushings and greasable bolts. The springs and bushings have been ordered, should arrive next week.

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  • 3 weeks later...

As a matter of fact, I was just taking a well-earned break from hacksawing the frame. I finally decided to bite the big bullet and move the frame ends up the full 7 inches. This places the rear spring eye a few inches above the front eye, which is supposed to give better handling. One day, after I lap Indy at 140 mph, I'll let you know if I did the right thing, LOL. I'm almost done cutting the first side, will soon move on to the second. I'm leaving the bottom flange intact, don't know if I can bend the frame ends up without heat or not. Should I ask my wife to lift up the back of the chassis while I use the torch or should I ask her to heat the frame rails? Maybe I'll just get the come-along and leave her to the gardening...

The set of 4 new springs arrived from Eaton Detroit Spring. Mike Eaton was easy to work with, did good work, shipped the springs in about 2-3 weeks. I'm working on the design of the various hangers and shackles. It was easy when they were abstract parts, but now that they have to fit EXACTLY, a lot of attention to detail is needed. The springs came with bronze bushing, including grease grooves. I'll get drilled, greaseable bolts to keep things lubricated. Fortunately, the off-road Jeep guys use them in their urethane bushings, so they are pretty cheap to buy. I wouldn't want to drill a Grade 5 bolt down the middle, cross drill it, and tap for a grease fitting, especially not 12 times (4 springs x 2 eyes plus shackle hanger points).

I started on the steering box. The original Ross unit from a 1929 President had a big rectangular flange. The Indy cars cut the flange off, turned the end of the part that holds the shaft for the Pitman arm, and put it in a big clamp. I think that was so the height of the wheel could be adjusted to suit the driver. I cut the flange off with an angle grinder, took away most of the excess meat, and my buddy turned the o.d. to 1.875". I'll make the clamp out of a weldment of 1/4" plate and some bars.

Another big moment was when I gritted my teeth very, very hard and ordered the 4 wire wheels for the car. These will be real wires with splined hubs and knock-off spinners, just like the old days. It took a lot of research to find out what size wheel to specify and the dimensions for a good splined hub, especially one to hold the inner and outer bearings on the front spindle. Here's a CAD image I made of how the wheels will look. Now, I'll have to do a lot of extra consulting work to pay for the wheels! Ouch.

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I've been busy!

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Edited by Gary_Ash (see edit history)
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The splined hubs to hold the front wheel bearings and the 1963 Buick Riviera brake drums have been a real pain to design. Originally, I planned to make an inside hub to hold the bearings and the drum, then use the 5 bolts on the drum to hold an external splined hub for the wheels. The problem was that I couldn't design the external hub to go over the inner hub near the drum surface and still have enough metal thickness to feel comfortable. I finally gave up and made one splined hub adapter that takes the two bearings on the inside, has splines on the outside, and holds the drum and wheels. These will be machined from 4140 steel, normalized before machining, then hardened and tempered to be really strong, tough, and pretty hard, but not brittle. Amazing how problems can be solved by the simple application of many design hours and cubic dollars!

The front hubs have the pockets for the bearings, the rear ones just have a tapered hole and keyway for the axle shafts. Of course, the rights are threaded different from the lefts, so that makes 4 individual - and different - hubs to be machined. This is an exercise in reducing a 40 lb hunk of 6.5" diameter steel bar to about 7 lbs of useful material. Most of it can be done in a decent lathe. The hard part is cutting 112 little splines around the o.d. of the 3.6" diameter tube. They have be exactly the right profile - not exactly a gear, but close. A few small companies around the world make splined hubs for cars like old Jaguars and Bentleys, but no one will tell you what the dimensions ought to be, especially for the nominal 72 mm size. Rudge-Whitworth invented and patented the splined hubs about 1912, so it's not like it ought to be a big secret, but it is. Anyway, I think I have a set of good-enough dimensions and I ordered a spare wheel center to be used as a gauge for machining the hub splines. The wheels and hubs WILL fit together!

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post-47871-143142356687_thumb.jpgHere is the drawing that appeared in an article by Ray Kuns in 1935. The 15-page article gives many specific details of the Studebaker Indy cars. Of course, in 1935, you could just go down to the junkyard and pick up the parts you needed - no more! His various books have a lot of useful information about building speedsters and race cars in the 1930s and later. The actual wheelbase will be about 103".

I was aware that there were a number of discrepancies in what he drew vs. what the actual dimensions were, but the drawing is generally pretty good. Errors that I now know about include his depiction of the cockpit width extending to the outside of the frame rails when it actually goes to the inside of the frame rails, a difference of about 4 inches. He may actually show the body width dimensions correct while drawing it wrong.

The other error, which seems to have led to my problem with the rear section of the chassis, is that he shows the eye of the rear spring hanger (where the shackle goes) to be below a line extended from the lower edge of the frame rail. I think my chassis builder relied too much on the Ray Kuns drawing and not enough on actually measuring the Studebaker car at the Indy Speedway Museum. Note that the Kuns drawing shows the rear shackle in an inverted position. I think a spring can be made to work that way, but I haven't found any photos of the cars that show a spring and shackle mounted like that. I suspect that Kuns got a day with the car, made a bunch of sketches and notes, then found that it didn't go together right when he made the publication drawings, so he faked it with the shackle. So, now I have to use the hacksaw and welder to make up for the mistake.

I've got one side cut and weld-prepped, will get the other done this week and try bending it to where it needs to be.

Edited by Gary_Ash (see edit history)
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I'm glad I put a 60,000 BTU/hr Hot Dawg propane heater in the garage last year! It was 6°F here this morning, warmed up a little by mid-day, but I needed the heat to work.

The cuts I made were about 1.33" wide at the top flange, enough to rotate the frame a full 16.5 degrees and get the shackle eye where it really is supposed to be. I made the second side cut, dressed up the cut edges, and put my jack under the tail section. Of course, the whole chassis lifted off the jack stands, so I placed a pair of the new rear springs across the frame rails just in front of the cut. I was pleasantly surprised to see that I could jack the rear up and have it pivot on the lower flanges, which I had not cut, no heat required. It took a few up-and-downs while I trimmed to get a uniform gap of about .040". I lined things up, clamped it tight with some ViseGrips with a 1/4" thick copper plate behind the web, and started tacking. As I expected, laying down some beads about 1" long, alternating sides, pulled the gap closed even more. I hammer-peened each short weld bead as I went, to stress relieve.

Once the welding was mostly done, I took the chassis apart - a bolted assembly has some advantages. This allowed positioning the inside joints for the best weld penetration. I ground down the outside and inside (web only) to get things flat and smooth. I left the inside weld bead untouched at the top flange for extra strength. I was too lazy to follow DavidAU's advice to cut out a longer pieces of the top flange to avoid a straight weld, but it's very good advice if you have to do this some time. I welded in a 4"x2"x1/8" fish plate across the weld zone on the back side. It's kind of a Band-Aid, but at least it's something.

So, I am happy to report that the shackle eye came up exactly where I wanted it, the rails didn't twist, and the welding went well. Here are photos.

And just for frosting on the cake, UPS delivered the splined wheel center I ordered from England on Monday. It's 8.25" diameter, 5.5" high, has 0.2" wall thickness, and weighs 5.5 lbs. It's a nicely-made steel part, looks like it was machined from a solid bar of steel - which would have started at more than 90 lbs. We'll use it as a gauge to check the fit on the splined hubs.

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Edited by Gary_Ash (see edit history)
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Gee, you guys are TOUGH! But, I know that you're just concerned for my welfare and worry about weld cracks, thank you.

So, I laid out a bigger, longer plate for fishplating both sides. They will be made from 3/16" thick A36 steel plate with a bunch of 3/8" holes to plug weld the plate to the 1/8" thick web of the rail, as well as welding on the edges. I took the DXF file of the fishplates down the street a mile to the metal cutting and fabricating place. They'll laser cut them early next week. Each will weigh 1.6 lbs. I'll go grind out the little fishplate...

I had been getting a bunch of other parts ready for them to cut and bend, so I took a bunch of DXF files. The laser cutting is excellent, narrow kerfs, dimensions on 3/16" and 1/4" thick plate to within about 0.005". I don't bother to drill holes, I just have them cut them in. That way, they are exactly in the right place. I don't even have to ream for bolt holes. They'll be cutting spring shackles, steering box mount, formed plates to go under the rear springs and mate to the shocks, brake backing plate adapters, etc.

I'm using TurboCAD for all the design work, by the way. As I need good CAD for business use, I got the top-end Pro Platinum version and run it on a fast PC. However, even the TurboCAD Deluxe basic version at $129.99 will do 2D and 3D. They offer pretty good deals from time to time that are well below the "list" prices. I'm drawing all the parts and pieces as I go, so I'll have a complete car as a 3D CAD model when I'm done, as well as the real thing. Assembling the parts in CAD has helped me find some errors before I started cutting steel.

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Yep... we can be vocal around here, but I concur with the disapproval of the mini-plate... the new one looks much much better. You would have regretted leaving it the other way when you finished. It's like building a house, you need a strong foundation. You can change paint colors, horns, interiors down the road, but the only way to change a bad frame is to go back to square one.

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  • 4 weeks later...

What are you running for an engine? Updraft or down draft carb? How about the trans.... free wheeling? Or are you going to mix and match chassis components. Any photos of the driveline?

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Ed:

The original 1931-33 Studebaker Indy cars used the 337 cu in President straight 8. In the 1933 race, the five factory cars were beaten by an independent entry running the smaller 250 cu in straight 8. Due to the depression, production of the 337 cu in engine was cancelled for 1934 and the factory was developing a racing version of the 250 engine when bankruptcy ended Studebaker's Indy program. At least one of the engines was installed in a factory car for tests. A few completed race engines were sold off, current locations unknown.

My engine will be one of the Studebaker 250 cu in straight 8's, as used from 1929-42 in Studebaker sedans. I found a couple of 1937 blocks to use - they look the same externally as the early engines, with the water pump on the left side. These used insert bearings in the 9-bearing crankshaft mains and also in the rods, unlike babbited mains of the earlier blocks. I've got one 7:1 compression aluminum head. Using old photos and some measurements from the existing Indy cars, I designed and made cast aluminum intakes for four Stromberg EX-23 carbs, as well as the linkages. The cam will be a hotter version of the stock cam with longer duration. While the original engines used a magneto because they didn't carry batteries in the cars, I'll stick with the stock dual-point distributor. My engine will look pretty close to the one shown below in the 1934 photo. Expected output will be 190-200 hp at 4000-4400 rpm, 250-260 lb-ft of torque over a broad range of rpms.

I've got a 1938 President 3-speed transmission, one of the "sideways" boxes with synchromesh. Gerry Kurtz can add an overdrive to it for me, if I decide I need one. Rear axle is from a 1928 Studebaker GB commander coupe with stock 3.31 ratio. With 7.00-18 tires on the rear, that should be good for more than 115 mph, without overdrive. I picked up five NOS axle shafts from Nelson Pease in Palmer, MA, passed along two of them to Bob Valpey for his #37 car. The original factory cars used the same axle with 3.09 ratio. Front axle is from a 1929 President FH sedan, about the same as the originals. My steering box came from the same 1929 President donor car.

Ed, I was in your shop in September with the other Studebaker guys on tour, if you remember.

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After a lot of traveling, I finally got back to finishing the frame modifications. My first attempt at fishplating the cut-and-welded frame rails didn't pass review, so I ground off the small plates and had some bigger plates laser-cut from 3/16 steel plate. There are ten 3/8" diameter holes in each plate where I welded the 1/8" thick frame rails to the fishplate. I added some lengths of stitch welds around the outside edge of the fishplate. A 4"x1.5"x1/8" plate was formed to fit inside the top flange where it had been cut and re-welded, and this got stitch welds around the outside. Each weld was hammer-peened while hot to relieve stress. A little grinding was needed to clean things up. The rails came out straight and, for sure, they'll have enough reinforcement now!

I also added a CAD image of my planned instrument panel. I have most of the Stewart Warner instruments from a 1931 or '32 sedan, just need a tach and oil temperature gauge. The current Stewart Warner "Wings" series has the right while-on-black markings and arrow/crescent needles. Too bad they used the wrong typeface!

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Edited by Gary_Ash (see edit history)
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Yes, John, I've done it before on my 1948 Studebaker M5 pickup truck, including the odometer wheels. I made water-slide decals on a color laser printer, coated them with water-base acrylic varnish for protection. For ink-jet decals, I use Krylon clear, but the Krylon will destroy laser-printed stuff. White numbers on a black background (or on glass) are a little tricky.

Here's a page on my web site that describes it: http://www.studegarage.com/instruments.htm

I made the CAD drawing of the instruments in preparation for restoring the ones I have. I was just hoping I didn't also have to re-do a brand new gauge, especially since the modern bezels are crimped on tight all the way around. Sigh!

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Impressive build. I hope to stop by some day and see it in person. I know of a mag in Maine I have been trying to buy for 5 years. It came off a Pierce eight in 1936. The car had a dual spark plug set up, the mag and a Mallory distributor. Custom manifolds also..... very cool. From playing around with vintage straight eight's with good carburation and manifolds just under 200 hp is workable. You got to spin them VERY fast! I think I would use modern piston/ ring packages along with new modern rods. It will run the build price up a little bit but is worth it not to put a hole in the block if you suffer oil / rod failure issues. Good luck. Ed

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  • 3 weeks later...

I was working on the support frame for the cockpit skin. I think the originals were made from 1"x1"x1/8" angle iron, bent to a 6" radius for the front parts and 8" radius for the one that supports the dash. I couldn't find anyone locally that could bend angle iron "leg in". One specialty shop in Chicago quoted me $600 to make three fairly simple pieces. On the suggestions from one of the local metal shops, I wound up plasma cutting the curves out of 1/8" flat plate, then bending 1"x1/8" flat bar to fit the outside of the shape. A little welding and I have 1x1x1/8 angle iron with exactly the right curvature. I was lucky that the parts didn't warp when I welded the pieces together, but I used some heavy weights to hold them flat on the garage floor while I welded. A nice steel welding table would help, but I don't have one. I may just have to get a 24"x24"x1/4" flat plate and set it on some saw horses so I don't have to crawl on the floor to do this stuff! I did buy a Harbor Freight pyramid roll. I had hoped to roll the full 1x1x1/8 angle with it, but it would take more horsepower than my arms can provide to get the 6" radius bends. It did work fine bending the 1x1/8 flat stock to a smooth radius.

Two identical "hoops" get bolted together back-to-back to hold the firewall and support the back of the hood and the front of the cockpit. On the original cars, there seems to be a stainless steel fender welt seated between the hoops to separate the cockpit skin from the hood. I found some stainless welt with a cloth leg at Bob Drake, a supplier of early Ford V8 parts - looks like just the right stuff, easy to bend, shouldn't kink.

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Edited by Gary_Ash (see edit history)
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Nice work Gary, I had to take a few weeks off due to us moving. I hate packing !! Its unreal how much stuff you can put in a three bedroom house. I hope to get back to the car week after next. I'm probably going to build my cowl piece somewhat like you did. thanks. That remindes me I need to charge my camera

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I spent the last couple of days machining some parts for the front spring hangers, the ones at the front tips of the frame rails. The guy who built my chassis had made a set, but they turned out to be not wide enough for my 2" springs. I had been fortunate a couple of years ago to receive two cast parts that were spares for an original Indy car. I really wanted to use them to include their DNA, as it were, in the car, but they really didn't fit the frame rails and my bolts for the spring eyes are much larger diameter (3/4"). So, I copied the shape of the casting and made four ogive-shaped pieces for the ends of the tubes that hold the spring eyes. I've got to get some short pieces of drawn-over-mandrel 2" o.d. x .188" wall tube to get thick wall tube. I don't want black iron water pipe from Home Depot.

I started with 2" long pieces of 2" diameter cold-rolled steel bar to make a pair of the end pieces. I had bought a small Harbor Freight 7"x10" lathe for jobs like this. Well, maybe there is a way to swing a 7" diameter part on the lathe bed, but the chuck that came with the lathe would have a tough time gripping anything over 3" o.d. Maybe you can grip the i.d. of larger parts using the alternate set of lathe jaws. I soon discovered that it doesn't have enough horsepower to make a cut deeper than .010-.020" or it jams and blows the fuse. So, it took me about three days to machine the four end caps at .010" per cut. In the end, the parts came out OK, finish was acceptable, and accuracy was good, like better than +/- 0.005". My advice would be that if you want a lathe, spend more money than the HF unit, and get something that will handle larger steel parts. If you are making miniature brass cannons or other tiny parts in aluminum or brass, the HF lathe is OK for the money, and it's better than not having any lathe. Also, be sure to buy some carbide lathe bits or you'll spend a lot of time re-sharpening the tool steel bits. I found that all of the bits benefitted from being stoned with an aluminum oxide bar to dress the edges - they cut a lot better.

I still have to get the DOM tube from Metals Depot or some other on-line place. My local steel shop doesn't carry it. I'll cut the tubes to length, machine out about 180 degrees of the tube, and weld the caps on. Then I have to align the tubes on the "paws" of the spring hangers and weld it all together. If you look in the first photo of my previous post, you'll see the front spring hangers and cross bar (wrapped in protective paper - they were chromed) on an original car under construction in 1932.

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Edited by Gary_Ash (see edit history)
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I've drooled longingly over those Chinese knockoff lathes but have yet to buy one ( up here it's Princess Auto instead of Harbor Freight, but looks like the same junk). I've been watching the auctions for something old enough and big enough to be good, but not totally worn out from being in an industrial setting. So far it looks like everyone else has the same idea and the premium units get bid up quite high. Also have to watch the voltage and type of power they were run on ( single phase as opposed to 3 phase electricity), there's some strange ones out there.

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  • 2 weeks later...

We just got back from a trip to England, touring through the Cornwall, Devon, and Cotswolds areas. On our last day, we stopped to visit Motor Wheel Service in Slough, near Heathrow Airport. They have just finished building a set of wire wheels for me, will ship them this week. I would have brought them home on the plane but excess baggage charges are really expensive. We met with Gary Gardner, the sales guy, and Dan, one of the technicians. They build lots of new wire wheels, mostly for older MG's, Bentleys, Jaguars, etc., which have splined hubs and knock-off spinners. Their supply chain is set up well enough that it is cheaper to buy new wheels from them than rebuild the old ones, but they do that, too. They bring in bare rims and wheel centers, punch and dimple the holes, cut the spokes to length and roll the threads, then lace the wheels, true them, and apply powder coat finish. Chromed and stainless wheels are also available, and they supply tires like Blockley racing tires. They also have splined hubs for a lot of cars, though not my project, as well as spinners. It's a very well-run shop, highly recommended if you want excellent quality wire wheels. Their web site is at www.mwsint.com.

I can hardly wait for the UPS guy to deliver my wheels!

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Excellent project. Many of us dream of such a fun project.

Just found the thread. I wonder a little about the web stiffeners at the chassis cut. Every structural web stiffener I have seen has a fillet weld all round (leg length equal to plate thickness) with no spot welds through holes. The welds transfer shear mainly and weld length is what counts. The rounded corners are good to avoid stress concentrations. There are two usual failure modes: tearing and buckling. Buckling will be initiated in the compression flange (usually the top one in your case) and tearing is more likely at a weld or stress concentration, usually in tension. Buckling can be prevented with a thicker flange and by a gusset perpendicular to the web and flanges, welded to each flange and the web. Tension can be reduced by converting to shear by welding on a stiffener such as you have on the web.

In NZ we have rules about Low Volume Vehicles such as this and it would need to be certified by an appropriate professional engineer to be allowed on a road. Is there a similar situation there?

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Spinneyhill, I'm comfortable now that weld cracks, buckling, and tearing will not be a problem for the repairs I made. I normally use a maximum of 1/4 to 1/3 of the yield stress as the maximum allowable level in the steel, and there is enough moment in the chassis cross-section that the car will never be close to that, even so. The back section of the chassis rails support about 1/8 of the unsprung weight or 225 lb/102 kg. How many g do you think can be generated when the car hits a big bump? I'm used to designing pressure vessels 3-12 meters in diameter and 5-30 meters high, as well as complex mechanisms, have been doing this for almost 50 years. I'm from the school that says, "If in doubt, use more steel!"

Fortunately, we don't need to have a PE sign off on a design for car chassis, even for 1-offs, at least not in the Commonwealth of Massachusetts. The most difficult part is going through the Registry of Motor Vehicles inspection by the State Police - they are principally looking for stolen cars and cars built with stolen parts. My claim is I merely replicated a design that was manufactured in 1932, and I will have a serial number plate from a Studebaker car built in 1932 but has been disassembled and scrapped in a way that didn't result in a destruction record on any databases. My car will incorporate parts from the original vehicle, and I have bills of sale for all of the major parts. In recent years, most states in the U.S. have eased rules about kit cars, specials, etc. so that this is now permitted.

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Excellent. I wasn't sure of your background and am impressed with your ability with CAD (another dream of mine, for use with 3D printing some day). I suppose the axle coming up at speed onto the spring bumper will be an important part of the loading too. Your more-or-less full height web stiffener will help deal with that, as will the wee plates holding the end of the cross member. My engineering mechanics are a bit rusty to work out the loads on the chassis.

Interesting that they used two angles back to back for the cowl shape rather than a T shape. I suppose it reflects the sections available and what they could cheaply fabricate in the factory.

Keep up the good work! It is an interesting project.

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  • 3 weeks later...

I just got some photos of the splined hubs in production. The basic machine work is done, hogging a 40 lb, 6.5" diameter blank of 4140 steel into an 8 or 9 lb finished shape. The splining will be done next week and the mounting holes drilled. The two-eared spinners have a coarse thread, 8 threads per inch, to lock the wheel centers in place. The markings in the photos are in Chinese, because that's where the work is being done. They show the left hand thread for the right side of the car and vice versa. There are also some small plugs that go in the outer ends for grease seals. I couldn't find a shop in the U.S. that wanted to do the work and had the capability to cut the splines. Soon, I'll be able to put the hubs on the axles and slide the wire wheels on! I still need to buy tires - 6.00/6.50-18 in the front, 7.00-18 in the back. I'm planning on the new Excelsior radials that look like old bias ply tires.

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Hello Gary, I am envious and happy for you of the progress you are making with your Stude. You will end up with a very solid car. Do you have any additional information regarding the light blue Studebaker racer (pictures posted elsewhere)? Can you tell what type wheel is on that car? Are they more like the spline drive from a Jag. or dental drive like a Buffalo? I have been modifying a set of Jag. XK-140 wheels and hubs onto another British make and having fun with it.

Alan

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Alan, I posted some pictures of the blue racer under Boojoe's 1927 Studebaker speedster build thread. The car was built from scratch in Argentina a couple of years ago, made to look like a 1926-style car. It has a later straight-8 engine (1928-29). The wheels were also made in Argentina by a company there. They have pretty good prices, but building wheels with splined Rudge-type 72 mm size centers was a problem for them at the time I wanted to order the wheels. The smaller sizes were in stock. The car is currently in Switzerland, I think. It had a transmission problem, but they found another one to use.

Were your Jag wheels 62 mm or 52 mm size? Motor Wheel Service has a wide range of wire wheels to fit Jaguars and other British cars, as well as splined hubs.

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What a wonderful project, LOVE IT...

My now deceased brother restored the 1952 number 16 Indy Offy that in 53 Art Cross drove to 2nd. I showed it at Pebble Beach in 2001. It was the Smith Special, also known as Springfield Welding sponsored car.

Loving this build.

Wishing you the best,

Dale in Indy

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  • 2 weeks later...

The wire wheel bits are coming together, at last. The four wire wheels arrived here from England, just a few days shipping time via UPS Express Saver. Now I need to order the 6.00/6.50-18 tires for the front and the 7.00-18 ones for the rear. They'll be mounted with race tubes having brass stems. The hubs are nearly complete now, just need final anti-corrosion treatment, then they'll be on the plane from China. These turned out to be very difficult parts to make, special spline-cutting tooling required, and electrical discharge machining (EDM) for the countersunk holes for the lug nuts in the rear hub assemblies that couldn't be reached by conventional cutters. The knock-off spinners are getting their final polish, laser engraved labels, and chrome plating. Real wire wheels with custom splined hubs are not for the faint of heart!

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