Jump to content
Model Cars Magazine Forum

One of the most famous race cars nobody seems to know anything about.....


Egilman

Recommended Posts

Hi all, 

First off, thank you for the views and support... Second of all, it's nice to see the interest in this particular piece of history....

But time has come to re-evaluate the progress and direction this has taken... As I have mentioned I've been working with whatever images and data I could glean from the net, but in reality that can take you only so far before the lack of accurate data starts to effect the outcome and inaccuracies start creeping into the design... It has become clear to me that I've reached that point...

This is where I finally wound up...

screenshot_593.png.471d8497d1c67c0c4037142b32975a6f.pngscreenshot_592.png.55990912b53963fe677fe691d4aba393.png

 

Correct, (kinda) motor mounts and a properly configured engine crossmember... with a much smaller flywheel....

This came about from the very kind contribution of some very detailed images that were gifted to me from Big John, (THANK YOU JOHN !!!) the process I'm working on requires revisiting what was drawn before and adding new details and features as the info comes available... I now have sufficient info data and pics to make almost EVERY part I've designed so far better and more accurate... Unfortunately many of those parts require a complete redesign to incorporate the new details...

Some of it I got right, a lot of it is close and some of it is just plain wrong...

So given the mountain of new information and pics... It's come time to start over... Those who do a lot of scratch designing/building know this process very well...

So I'm here to announce Version 2 will be starting soon.... 

So don't change the channel, don't go surfing... 

As soon as I get my new base images indexed and loaded into SW, I'll be restarting the log...

Look at it this way, you will get to see this built right from the start, creating a frame.... It won't take long and I'll be using much of what went before, but I will be adding the details that I now know exist which I didn't when I first started this project...

Amazingly the images I now have access to show that quite a few of my guesses in how she was configured were amazingly accurate despite not having absolute proof of their configuration...

Anyway, Onwards, and I apologize for the delay which has become painfully necessary to reach the end of my stated purpose, create the most accurate model of the Marmon Wasp currently in existence...

Thank you in advance for your patience...

EG

Link to comment
Share on other sites

Hi all,

First iteration of more accurate parts....

screenshot_595.png.b38c89c1e279d6f59c56afd1d6c56e47.png

Left Frame Rail, new on the left old, on the right...

Next up the front suspension bracket, it carries the forward end of the front springs and the Shock Absorber upper mount... It's what those four forward rivets are securing...

Now, Right and left rails....

screenshot_596.png.82c2fe706d416496ec4c56ca265f2574.png 

Onwards.....

  • Like 1
Link to comment
Share on other sites

Thank you for those pics John, they really spell out what they looked like and how they were mounted...

I just finished off the Rear Crossmember....

screenshot_601.png.f51ed4727335076221cbdd018bb39f54.png

screenshot_602.png.226b6262645cc077a340d26879b6fa58.png

And the reverse side in the frame...

screenshot_603.png.b4be292f18865fbac31cf70ef917b514.png

Man those pics are so detailed, I can even see the correct form and mounting for the rear springs, it's a lot more involved that just a bracket bolted to the frame...

And an overall view....

screenshot_604.png.8732096235bbf280e4752a049dbcc8f9.png

Currently looking at the next cross member forward, the one at the back of the drivers seat, it carries the frame for the rear body and fuel tanks....

Onwards....

Link to comment
Share on other sites

Another update...

These would be the Rear Firewall Crossmember, The Brake intermediate shaft cross member and the Center Thrust Crossmember....

 

The Rear Firewall crossmember, It carries the forward end of the Fuel and oil tanks and the rear wall of the cockpit....

screenshot_607.png.9f57b21d6da8ba67d15279dedec057f3.png

The Brake Intermediate Shaft Crossmember... It carries the levers and torque tubes of the brake system from the left side of the chassis to the right side to actuate the right side brakes simultaneously with the left side...

screenshot_608.png.f45a6ea76a5951457a5ae69592d3050c.png

Those two crossmembers are simple angle irons welded to mount plates and riveted to the side frame rails, pretty simple...

Finally, we come to the Center Thrust Crossmember....

screenshot_609.png.f13fd77316e11cf290c6284a8633530d.png

The Center Thrust Crossmember is the most important cross member as it transfers the push of the driveline to the frame keeping the thrust load of the rear axle & wheels off the springs... It also carries the emergency brake input shaft and the forward end shifter gate which transfers the motions of the shift lever to the shift rods leading back to the transmission... It is made of 3/16th flat steel press formed into a channel and riveted directly to the frame rails... It is the strongest of the six crossmembers making up the frame...

An overall view of the Frame where it stands today....

screenshot_606.png.e64c6d13d4e7d64bd5016e038a34d8fc.png

Next up, the rear motor mounts and crossmember....

Onwards....

 

Link to comment
Share on other sites

Well another update...

Full frame...

screenshot_610.png.ab093855585442873a491aaf079f9674.png

Except for a few minor details miscellaneous holes bolts & rivets, (added as I add more parts for the most part) she is complete!!!

The increased level of detail also includes a bit of narrowing, as I was adding parts on the previous version she started feeling a bit fat so I rechecked and took an inch and a half off her width... Should help with the fitting of parts in the future...

I also dropped the engine back into her....

screenshot_615.png.bbde543a85940f40de4246a509096a32.png

It's the only part that hasn't been adjusted as of yet.. (although I will be adjusting the crankcase flange shortly to correct it's shape)

Anyway this is the status as of today, Happy Easter everyone...

EG

 

  • Like 1
Link to comment
Share on other sites

Thanks John... Your pics really make a difference...

Currently done the rear shock mount, it went rather quickly as the original wasn't that far off... The Spring mounting bracket is another creature altogether though... Requires a complete redesign cause my original was way off...

Working on it now, next update when it's done....

Link to comment
Share on other sites

Update:

Rear Shock mounts and Spring brackets... (the shock mounts were easy, the spring mount was another story)

Overall view of the area...

screenshot_616.png.2fd5325967a1dae03dcce3adc57ae05d.png

Nothing unusual to the casual view....

Where the spring brackets live....

screenshot_617.png.d15a7e116aed35e1e93e52103b6c354c.png

Different aren't they! not just bolted to the frame... but looking at their actual configuration the mechanics makes sense... And I might add a perfect application of the lever to reinforce the spring pivot point...

Out of the frame....

screenshot_618.png.3941fcd0512ed1a6adcbda6bc5dc9c01.png

And of course an overall beauty shot... I know, it's only beautiful to us engineering types who like this kind of stuff,.....

That's it for today, I'm now on the road to a rolling chassis again...

Thanks for your patience with me...

EG

screenshot_619.png

Link to comment
Share on other sites

  • 2 weeks later...

Well another update, this one took a while to create....

Front Springs....

screenshot_621.png.b242e9d6c2721a8436771dce37b5c595.png

Eight tries at it, five complete redraws..... 2" x 35" Asymmetrical Leaf Springs.... The Axle mount centers 15" from the front pivot point leaving 20" behind the axel The leaves are 1/4" thick at the Axel Mount and taper to 1/16" at the tips and the tips are full width radiused... (my originals weren't)

screenshot_622.png.132d82efccd96b93845ae306b102bb7a.png

And they are mostly one piece, the two shackles are separate pieces as well as the rear pivot hanger...

It wasn't easy...

Overall look...

screenshot_620.png.c182644ee9178530b5355059d891ee8e.png

I'm going to take a break for a few days, have some RL issues that need to be dealt with, but then after a suitable rest for the brain, I'm going to tackle the rear springs....

Onwards my friends...

  • Like 1
Link to comment
Share on other sites

Posted (edited)

Thanks for the like John It's appreciated....

And I've started the Rear Springs.... First I have to create the mounting plate, it's the pivot point of the upper spring and carries the load from the Wheels & Rear Axle vertically to the frame...

Mounting Plate, A lot different than first envisioned....

screenshot_625.png.84f2b5ea3c99f0a9d2dec74b9772844a.png

Thanks to the pics John provided, much, much more accurate....

Reverse side, attached to it's mounting bracket....

screenshot_624.png.e61f9c55b9adc95af3400a8641633b18.png

And finally in place against the frame.....

screenshot_623.png.07becac8607c0b37d6463e6c88f0af69.png

Now I start to build the upper rear spring....

Onwards....

Edited by Egilman
Link to comment
Share on other sites

Well another update...

Rear Springs, I was hoping that I would be able to use the springs I had already made to build the second version... Unfortunately no That wasn't going to work so I've set about building a whole new set of Rear Springs.....

screenshot_628.png.5f33915d95e5e2f7c42d643921af8a68.png

screenshot_629.png.dcaa32fa72fc2247328c58f0469011ce.png

screenshot_630.png.1bd5f8ac7de0ec078e77482c29c1146d.png

And in measuring it against the detailed photos I now have I found that I also needed to rework the Bracket as well to more accurately reflect it's true position on the car... 3/4ths inch closer to the rear and up at the turn of the curve on the frame rail...  

Then I added in the old springs and the ends sat way to low, so I was forced to completely rebuild the springs reflecting the correct measured position on the car... The curve is now accurate, 40" long by 2" wide with a 3" drop at each end... 

I've included two pics showing the current iteration colored in the cars natural yellow color....

screenshot_627.png.536947927beebd259fdbc8566b179a6d.png

And one of the spring itself showing the upper mainspring and first leaf...

screenshot_626.png.0baf851e5ff65329d4eb854b1a7745ff.png

and it's one solid piece as well....

Next posting when the spring itself is finished...

Onwards.....

 

Link to comment
Share on other sites

And now the bottom springs are done.....

screenshot_634.png.111df97cfd87bbe998b988eaa5041f3f.png

screenshot_635.png.2298116d28f68f1a5c1abb68a8cd0a1a.png

Fun times, And before I go on to the next part, I've got to reconfigure the front springs to better match the rears....

An overall look....

screenshot_636.png.cd66dc0efb6ef4d5902a87de3c908f49.png

Haven't decided which direction I will go next, but it will be one of the Axles....

Onwards...

  • Like 1
Link to comment
Share on other sites

Update:

Front axle...

screenshot_637.png.96ce5b138d04d383f4fd2d63b4a0a913.png

Overall, (along with the front Shock Absorber Bracket)

screenshot_638.png.0f958c56b33c8fd9bc51c647b7a033fa.png

Now to design the spindle tubes, leading to the Spindles themselves at which point I'll incorporate the camber, (outward lean) and toe-in, (narrowing of the front wheels at the leading edge) All improvements of the front steering engineering of the automobile...

It's good to note that in 1910 they understood proportional steering, camber and toe-in and how they effect tire wear and turning control, they were still working towards castoring front wheels... (heck most people don't understand steering geometry even today)

But they still did not understand body roll, moment of inertia, weight shift and thrust angle, nor why they were important... 1910 was a period of discovery in the auto industry and Indy was intended to be the proving grounds for auto engineering advancement...

The steering of the Marmon Wasp incorporated all they had learned..... I'll attempt to explain it as I go.... (what little I understand)

Anyways,

Onwards...

Edited by Egilman
Link to comment
Share on other sites

Thanks John...

Yep, I saw that...

The twin mount on the right side is the original, made from 5/16" steel... Day of race pics clearly show four shocks on the front mounted inside and outside the frame rails... The left side is a replacement to make her drivable made out of 3/8" steel.... It sits too far forward as well as being only a single mount....

Inner right side...

1911-5052-28-marmon-040.webp.6f8c6497a1a666c6e1965158733c1c23.webp

Inner left side...

1911-Harroun-and-Marmon-Wasp-900-600.jpg.d1f51b266210ea7bf8fe13893feb4103.jpg

Edited by Egilman
Link to comment
Share on other sites

Thanks John, been working on her steady this week as time allowed... Here is the current status....

Left side...

screenshot_643.png.769bb3a27391558c3a83d7497fa67d42.png

Right Side...

screenshot_644.png.626fa95a4088ca7531499559b9e5db30.png

Front....

screenshot_645.png.128d97355990538ba32beca6abf4fc75.png

Rear...

screenshot_646.png.5065996b6c1dfff7f977e6ab6668f7d7.png

I haven't drawn the Steering Knuckles yet, but I've learned they were identical from side to side just mirrored... The steering arm was a separate part that was bolted on over the right side knuckle so it is unique to the Wasp... My previous design was of the standard steering knuckle/arm, (one part) from a standard Marmon Speedster...

 

Your pics of what is actually on the car are a godsend for getting it right...

That's what I'm figuring out now, the steering knuckles will be easy, it's the steering arm that will be a challenge...

Again thank you for your generosity....

EG...

screenshot_647.png

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...