77 replies to this topic

[Mopar Rob]

With the Sano III rapidly approaching, I decided I needed to build some more cars. Some of the West coast guys seem to be ripping it up with Tripod chassis, so that what I'm building.

Did the layout in AutoCad last week and am waiting for my friend Bill Worden to finish making the pieces. As an interim, I started with the main wire. It was very easy to bend up using my Retro Pro jig, purchased from Mike Swiss at Chicagoland Raceway. Special thanks to Geary Gaspord who was able to supply me with some replacement parts due to my wife's cats or my eight-year-old?

Using a JK bracket and a Chicagoland axle tube.

Need to call Swiss in the morning. I just realized I don't have any guide tongues.

[Mark Wampler]

Just being a little nosy. It's fun to build your own guide tongues.

[Mopar Rob]

Unfortunately, I'm not the machinist. I'm just the guy with mediocre AutoCAD skills, a Retro Pro Jig, and a soldering iron. Bill's making the parts on a hobby mill in his basement. I do have an alternate design with an integral tongue, but that probably would require being CNC or waterjet cut?

Just trying to make the chassis with equipment that's readily available to most hobbyists.

It would be nice to make 100% of the chassis including the tongue and motor bracket

[MSwiss]

Knowing Rob, I'm sure he wants to take advantage of being able to use a steel guide tongue. The majority of even hardcore builders buy those vs making them from scratch.

[Lucky Me]

Rob,

I can attest that this design works Very well. I built one also using pictures of Mike Steube's car. You can view the build HERE.

It is also a very lightweight build. When properly balanced it should be a jet!

[Mopar Rob]

Rob,
I can attest that this design works Very well. I built one also using pictures of Mike Steubes car.

I initially looked at Steube's car for insparation, but also picked up design ellements from your build and Rick's chassis kit. That's what makes scratch building interesting

Photo and Kit below by Rick Bennardo

[Mark Wampler]

I learned to make guide tongues from the Steube scratchbuilding vid. Drill press, calipers, punch and a shop grinder were all that was used.

[911GT3]

Another Ohio Valley racer built a tripod chassis and it was jet at Tom Thumb. Look out Rick, Neil is gunning for you.

[Mopar Rob]

I'm told the pans are done. Bill told me he's waiting on an 1/16" end mill to make the wire slots. Should have all the parts by the weekend to finish the build. For now I'll post a better picture of the design.

[Lucky Me]

Another Ohio Valley racer built a tripod chassis and it was jet at Tom Thumb. Look out Rick, Neil is gunning for you.

Neil was at the Fatboys warm up race, we pitted beside each other, I looked over and thought he had my car , come to find out he built 3 of these and they are fast !
I think Neils game just went to another level. I think we are going to be seeing more Tri-pods in the Very near future. I will be starting my 2nd one soon. They doooo work !!
Cant wait to get some feedback from Rob on his current build. I will be watching this thread closely.

[Pablo]

Thanks for sharing, Rob.
I don't know anything about CAD but it looks pretty cool

Interesting design......some guys are making rails converge at the front, and some (like you) are making them go wide at the front.
I'm still in the late 60's, making them straight

[Mopar Rob]

Thanks for the interest.

All the design engineers at work, design in 3D using ProE. I use AutoCAD because that is what we use at work for plant layouts and that what I'm working with most of the time. Cant expain how cool the technology is becoming. We have a couple of 3D visualization labs that words cant explain.

Maybe one day I'll start playing with 3D design?

[Pablo]

One thing I always have a hard time with, is estimating how far forward the flag can go without conflicting with the body.
I'm sure 3D would fix that

[Rick]

Rob, looks kool. I have yet to see a tri-pod chassis built. Lots of quasi tripods are there, no true ones yet. The one kit I cut was a true tripod. Tripods have no parallel rails.

This one I tested Sunday, much too stiff for a Hillclimb, I think it would be a killer high speed King track chassis with the guide tongue shortened up.

[gascarnut]

I have a question:

Why are these frames called tripods?

Literally, a "tripod" is something with 3 feet, like a wing car that rests just on two rear wheels and its guide.

These frames are quite obviously not just resting on the rear wheels and the guide, so what's with the misnomer?

[MSwiss]

IIRC, the term "tripod" in slot car chassis came originally with three-railed triangular wing car chassis around 1985.
Early on, most were made of piano wire in Texas for G15 racing.
Tom Hansen had a steel G7 version that held the single lap World Record for a time.
In most cases they were wider in the front.
When Koford started selling a twi-railed tapered chassis, it was coined a Bipod.
One with less taper going to the rear was called the Wedge. It had 3 rails.

While correct, the "guide shoe/only rear tires touching" tripod stance of a wing car car never was never really referred in Pro wing car racer chit-chat.

[Hworth08]

Tripod? Because it sounds cool, kool, kewl, ect.

Racing products often sell better to the public because of their name than their proformance. The high lift cam, tunnel ram manifold...

[Jairus]

Taper-rail?
Wedge chassis?

[Prof. Fate]

Hi

I have seen various definations and I don't know that anyone screens them for "korrekt". Grin.

All my cars that seem to have 4 wheels are actually "tripods" as in the weight is carried by the guide, not the front wheels.

Fate

[Mike Patterson]

Rob, when are you going to do some assembly?

[Mopar Rob]

Rob, when are you going to do some assembly?

This weekend. Would like to have it built by Saturday night to test at Mike's, but wont rush it to make it happen. Have another chassis to test anyway.

My friend who does the machine work had some personal stuff he needed to do when not at work. He finished up some D3 F1 pieces (build will come after this chassis) today. He also needs to fabricate some sort Jig which will require machine work just to do the chassis machine work or so I'm told.

[Mopar Rob]

Have another chassis to test anyway.

Worked really well until I hit a car that de-sloted in the straight during practice. Then stepped on one of my others after I dropped it on the floor. Figured since I took out 1/2 of my Can-Am fleet before I even raced, I needed to go home and build some replacements until the others could be fixed.

Here are enough pieces for 4 cars. Need to soak in laquer thinner to seperate them, since their glued together. Will start build tomorrow

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[Jairus]

Rob, I noticed that a taper rail like the one in this thread provides more movement at the back end of the chassis than at the front. Much like a full plumber/floppy pan chassis of the old days. You might be on to something here....

[Mopar Rob]

First thing I do is de-burr the chassis using P400 wet/dry sandpaper. This is a throwback for me to the days of building Open 12 chassis and removing the Laser Oxide on the chassis.

Off to make some breakfast. Don't want to wake the sleeping members of my household up with Dremel tools and other noisy tools

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[Mike Steube]

The inspiration for the first chassis I built with this basic design was from a 60's Thingy I saw in the Thingy forum. They must be Thingy chassis', not Tripods.