# Dropped Magnet MagnaTraction Style Chassis: The Build



## K.L. VanAtta (Mar 23, 2009)

Good Afternoon,

From the number of hits my other thread has, I decided to do a tutorial on how to build a chassis like the two dropped magnet chassis' in the original post. I have been taking photos as work has progressed and will use a photo to illustrate what I'm doing.

Please ask questions and give comments. I will learn as much as anyone from your observations.

Thanks,

Keith L. VanAtta a.k.a klv


Dropped Magnet MagnaTraction Style Chassis: The Build

I first saw a dropped magnet style car in 1971 at a Michigan HOPRA race. It was a full brass pan competition AFX chassis with lowered magnets through the plastic chassis to sit on top of the brass. The evolution began.

By the first HOPRA Nationals the cars had just enough plastic to hold the magnets, electricals, wheels/tires, gears/axles, and a body. Sounds like a lot, but wasn't a lot there. 

The car I'm building is a modification of a 1974-75 Amateur class car for Michigan HOPRA. In '74-'75 magnetic shims were allowed, which makes the car MUCH harder to set-up and drive quickly. The build chassis has just dropped magnets, easier build for you, much more fun to drive, and less costly all around.

Let's begin.

Gather up your tools, the more tools you have the better prepared you are, and round up some parts. At this point all you really need is a MagnaTraction chassis and a pair of magnets.

I would save the real MT chassis and use an Auto World or Johnny Lightning. Yes, I know they have some issues, but we can overcome them.
I'm using a Johnny Lightning soft black plastic type, we will be doing a lot of cutting on it.

I just grabbed a pair of magnets, each Gaussed in at 562G, after zapping the reading averaged 575G. A lower middle range pair, good for this project.

The last item in the picture is my steel armature plug, good for setting air gaps, setting perpendicular magnets, and a million other uses. It has a 0.700 inch diameter and made from soft steel: did it myself on my lathe.











Okay, for one of the hard parts. You need to remove the pickup holders/brush contacts from the chassis. To do this grind or drill the rivets off, but, YOU NEED TO SAVE THE RIVETS. Take a Dremel and a pointed grinding bit and grind off the top portion of the rivet. Grind some then gently test if the plate will come loose, if not, grind some more and test again until they come off. Plate and half a rivet. Clean up the mangled part of the rivet so you can reinstall it later.











Photobucket is doing maintenance and I can't get to my photos. Will continue later.

klv


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## chappy2 (Jan 7, 2013)

Awesome KLV, looking forward to following your build steps.

Chappy


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## sidejobjon (Jun 3, 2010)

We Love walk threws
Thanks SJJ


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## K.L. VanAtta (Mar 23, 2009)

Good Afternoon,

Photobucket has returned and the build photos are available again.

The next photo shows the five parts we should have after removing the pickup holders/brush contact plates.

To prepare the rivets, get a six inch length of 0.032 wire, a Dremel, and your smallest grinding bit. Place the wire through the rivet, mangled side facing up, and take the grinding bit with the Dremel set on the slowest speed, gently touch the mangled part of the rivet until it spins. As the rivet spins, the extraneous parts of the rivet will be ground away to manageable size. The rivet needs to go back into the rivet hole in both pieces upon assembly.










Next, lightly sand the top of the chassis. I use a piece of 220 grit paper and use 40 circular passes. This shows some potential trouble spots. Look for unsanded areas like gearplate hangers; this could indicate a slight twist in the chassis.










I think that will do it for today. Next up is cutting the chassis to allow the magnets to drop freely through.

Thanks for letting me ramble....klv


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## K.L. VanAtta (Mar 23, 2009)

Good Morning,

Part 2

Everyone can relax, the difficult part is over.....ah...sorry...just kidding. Or to use a favorite adjective from one of my favorite movies, "Repo Man" (1984), "...intense...". The next few hours of cutting and shaping will be "intense".

The tools needed are a Dremel, cut off disk bit, flat disk grinding bit, hobby knife with a #11 blade, a thick, sturdy square cutting blade for the hobby knife, not a single edge razor blade. A flat, course file, a round or half round file, some of your favorite music, and a bottle of pop (soda) or water. Almost forgot, your favorite animal companion; mine is a 10 year old Maine **** cat that lounges on my workbench directing progress.

Begin by scribing two lines across the bottom of the chassis from one leading most edge to the other leading most edge of the front magnet opening. I know that there is very little room and that there are two different depths of material. Take your time, realign your straight edge as needed, and mark down which line is the correct line.

Flip the chassis over, still working on the front magnet opening, and make five or six cuts along both contours of the plastic strip that holds the magnet from dropping through. Don't cut though yet! Now, on one of the contours begin to make small push through cuts that nearly go through, I mean small, 10 to 20 cuts, and don't go through the plastic.

Repeat this last cut again, this time with the intent of cutting through. The piece should break away with minimal effort and blade work now (Note; having a clean cut, or something close, will save time when filing. You now have max 2 minutes of filing as compared to a straight cuts 5 to 10 minutes.). Use this procedure on the other end of the plastic strip to remove it entirely.

Flip the chassis over again. Looking at the bottom of the chassis and the two lines that you've drawn, get the Dremel and fit it with the cut-of disk. Set the Dremel to its slowest speed and begin to make a cut as close to the horizontal line across the chassis as you can without nicking the chassis. I generally end up 0.032" to 0.063" away from my lines. Finish removing this piece with a hobby knife.

Smooth the area with the face, not the edge, of the cut-off disk, and the grinding bit, go slowly. While the course file can remove large amounts of material quickly it tends to be uneven, you need a bit of experience to know how this file will cut in your hands. I rough cut with the file, smooth with the Dremel, and then finish file.

The end result will look like the picture below. A half circle that is flat on the top a bottom. The magnet will fall right through.

Repeat this process to the rear magnet opening.













Removing the inside magnet retaining posts is one of the most difficult things I can think of in building an AFX type chassis for me. Until I found the blade necessary to do the job right. That blade, I don't know the number, is a long rectangular shaped blade that is thicker and stronger than any other I've seen. Its cutting point is squared, single edge, 0.250" wide, long taper, and very sharp. It take the pressure of the cut without bending, an added benefit.

Builders/Customizers/Racers remember, working with these sharp tools can result in injury. I always try to find the safest places for my fingers to hide when I'm working in small spaces. Please be careful and safe, if you don't like the technique I described or feel uncomfortable with it send me a PM or ask a question in the thread, among us we can come up with something.

Look inside the motor compartment, see the four posts that hold the magnets from hitting the armature, we want to remove them. Take your knife, find a position that is comfortable and allows you to cut from the top of the post to the bottom without interference. Start at the inside of the magnet box and, using the magnet box wall as a guide, rock the knife across the top of the post.

Do this again. The next time apply more cutting pressure while using a rocking motion to cut. Keep an equal pressure throughout the cut and stop at the bottom of the post, or near it. Through the chassis opening opposite the post pull the blade as close to flush against the bottom of the motor compartment as possible and at the base of the post. Cut with the same rocking motion and after a few cuts test to see if the post will come out. If not keep cutting a little at a time.

While it is not totally needed to remove these posts, removal maximizes the potential of the magnets you have to work with. Allowing you to have the best air gap, magnet to armature, and flattest magnet surface to maximize downforce.

Later.....klv


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## LDThomas (Nov 30, 1999)

Thanks Keith. Loving it...


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## K.L. VanAtta (Mar 23, 2009)

Morning,

Finished editing Part 2. It is all there now. I mistakenly closed the browser tab and had to retype half.

klv


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## K.L. VanAtta (Mar 23, 2009)

Good Morning,

On to the next part.

Part 3

The next step is to replace the pickup hanger/brush contact plates and rivets, and installation of the magnets

To our tool collection we are adding a steel plate, alligator clips, c-clamps, a couple pair of pliers, and two type of epoxy. The goal is to straighten out the plates while we have them off the chassis, thus solving one of the quality control issues with the stock chassis. To install the magnets in a manner such that they stiffen the chassis and provide the greatest magnetic field for the armature and downforce.

Straightening the plates is no big deal. Put the entire flat portion of the plate in the pliers leaving the brush contact arm and the pickup spring cup free. Now bend, twist, and tweak the arm and cup until they are in alignment with the flat portion in the pliers. When you are happy with it (or give up) check by holding it down on the chassis at the rivet point. It will look straight and even if its close, by shifting the pressure a little to the center of the chassis the contact arm will drop in its' slot.

One plate will need to be trimmed to clear the dropped magnet, this is easy when you take your time. Be sure to trim it back to the edge of the magnet opening. Now to epoxy one at a time on.

Rough up the two surfaces to be glued together with a Dremel and a hobby knife. Mix up some 5 minute epoxy, I used JB Weld, and apply it to the chassis on the boss that holds the plate. Drop the plate on, find the rivet and drop it into its hold in the plate and chassis. Use tiny alligator clips to apply pressure on the rivet and the leading edge of the spring cup (see photo). Let it cure for 10 minutes. Do the other side.










Now that the epoxy has cured and the plates and rivets are reattached to the chassis we can move to the magnets. Finding a matched set, or matching a set of magnets is all well and good if you have the necessary equipment to do a proper matching. For this build the number of paperclips the magnet can pick up will suffice.

What I think is more important is dimensional matching, making sure the magnets are close to very close in size. You wouldn't pair a 0.250" tall magnet with one that was 0.300" if you were building a MagnaTraction, would you? I got lucky and pulled a pre-matched set of magnets from my supply each Gaussed at 562G, and one was 0.295" tall and the other 0.301" tall, that within 0.6% of each other, very close. I use a BOW (Best of the West) magnet zapper and after zapping the magnets averaged mid 570G, a 2.**% gain.

I polished each magnet with a wire brush in my Dremel and polished a little more with some crocus cloth on the inside face of the magnet. You don't have to do any thing I described above, just that old habits are hard to break.

Clean off the magnets with tape so they are dirt and grime free, epoxy will adhere better too. We'll set the magnets aside and decide how much to shim the magnets from the steel plate. We are shimming away from the steel plate to 1) give us room to sand the chassis down, 2) create a space for the pickup shoes, 3) the ability to use smaller wheels/tires, and 4) once sanded the rear magnet will be flush with the chassis and square to the track surface.

Shimmed the front magnet 0.020" and the rear 0.010". Put the magnet air gap tool in and place the chassis on the steel plate and set the magnets in place, feels like stuck to the plate.

This is where I discovered a 3 degree twist in the chassis I was using. After fiddling with it and thinking about it I decided that when the magnets were epoxied in, if I took the twist out with the c-clamps, the rigidity of the unit would keep it straight.

Looking at the set up you will see some large gaps between the chassis and the magnets. The goal of glue in the magnet is to bond them with the chassis and I like epoxy for this, specifically a slow cure, 30 minute version. Look at the photo to see some of the places I applied the epoxy, anywhere there is a gap on the side or back of the magnet. Use a lot because it will flow into the gaps sealing them. Then, let it cure over night.

Go say "Hello" to your family.

Thanks....klv


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## ruralradio (Mar 11, 2011)

Last time I built a dropped mag car was the summer of '76, a motel room in Lake Bluff Ill., the Firesign Theatre on the stereo, and some guy named Thurman drifting about the room doing all manner of hippie things.....:dude:

Welcome back, Keith. Stay after it.

BTW, KLV, it was because of your doing that I was there in the first place...... have I ever thanked you?


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## K.L. VanAtta (Mar 23, 2009)

Chappy2, SJJ, LDThomas thanks for the encouragement! 

Everyone who has stopped by to what this thread is about, thank you!

Pat, After 40+ years of friendship some things don't matter any more. The important fact is that we were both there to experience it with some friends that we're still in contact with.

Hey, remember Otisville Bar and Grill and the hamburgers?

Keith

Tried to get my 25 year-old into Firesign a few years ago, she didn't get it! Gave me this weird look when I told her the title, "How Can You Be Two Places At Once When You're Not Really Anywhere At All?".


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## TeamMadMarsupial (Dec 23, 2012)

Wow, this thread is like a trip down memory lane! We must have dropped the magnet on a hundred of these chassis back in the day.

Thanks for posting the build.


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## shocker36 (Jul 5, 2008)

Nice build I often think I was born 15 years to late as I missed all the cool racing from the 60s and 70s wether it was slots, canam, or drag racing etc


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## K.L. VanAtta (Mar 23, 2009)

Finished Part 3.


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## K.L. VanAtta (Mar 23, 2009)

Finished Part 3.....klv


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## T-jetjim (Sep 12, 2005)

This is awesome. Can't wait for the rest!


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## 22tall (Jul 28, 2002)

Thanks for the blast from the past KLV. 

There are a couple things I have changed from those days. First the safety issue. I used to cut my thumb in the same place all the time. I switched from putting a band aid on after the fact to before cutting. Haven't bled for my hobby for decades.

When it comes to holding things together I have been using E6000. It is a rubber cement on steroids. As KLV mentioned epoxy is great for filling gaps. I put electrical tape on the visible side. This will give you a smooth joint.

Looking forward to the rest of the build.


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## K.L. VanAtta (Mar 23, 2009)

Good Morning,

I want to thank 22tall for the two worthwhile suggestions, never thought of the band-aid solution, and the adhesive market has become so much more "high tech" then it was in the 70's.

Thanks to T-jetjim, shocker36, TeamMadMarsupial, and RuralRadio for stopping by and the kind words.

It's on to Part 4.

Say that we have let the chassis set and cure overnight and that the epoxy has bonded to everything use a hobby knife to separate the chassis for the steel plate and remove the steel air gap plug. Take a good look at the chassis, see if you can cut away any epoxy overflow and do so, check all the magnet to chassis joints and repair as necessary. 

Once you've finished this you're ready to begin sanding. A word about sanding; never apply too much pressure, take your time, and check progress often (as much as I like building cars, I like to build a particular car ONCE). Be sure to catch any problems early so that they are correctable, not later when they are terminal. You'll find a comfortable level for yourself that will sand the chassis/magnets quickly, give a smooth face, and be square to the track surface.

I use 220/280 grit sandpaper and a known flat surface to do the sanding. This where one of my many 1/24 jig blocks becomes essential, currently I'm using a low cost one from Lucky Bob's, nice and flat, but, there are so many available currently it's hard to go wrong. My favorite is one made by "GoatBoy Products", Ian Thomlinson (I believe) a square, flat, and true, block made of aluminum alloy, nearly perfect.

You'll sand for a while, checking your work, and soon you chassis will look like the photo below. 










Here is a list of the parts in both photos that are on the chassis:

-G+ Rear Hubs
-Super Tires Tyco Silicone 0.430
-G+ Rear Axle
-1/16" brass tubing front axle
-JW's HO Speed Parts Aluminum standard Hubs
-T-Jet Front Tires

I apologize for not having a before sanding photo of the chassis and the glare in this photo around the rivets. The rivets are sanded down with the removal of plastic and epoxy. In the end the head of the rivet is somewhere around 0.005" thick, a great way to gauge the amount of sanding you have done.

I put the sets of tires on the chassis to get an idea of what size tires I will need to maximize the magnetic downforce (remember that magnetism is an "Inverse Square Law" force). I'm looking for something in the 0.005" clearance range on silicone tires to be satisfied, but, if I go the sponge tire route I'll try 0.010" to allow for compression (I found a plastic bag full of Buddy Bartos 1/24th sponge donuts that have the mounting hole at 0.275" and are 1.50" long, firm sponge, might have to make some tires). With the wheels/tires you see in the photo I had about 0.020" clearance front, and 0.027" rear.

I'm going to post one more part Monday and Tuesday, Part 5 and then sort out the tire situation. I can continue with Part 6 after that, rather give you a completed project that works then not.

Thanks for stopping by.....klv

* I have had the chassis running with every combination of tires I have presently. Runs like a Fray car with an AW arm on my tiny, tiny track. Made steady improvement as I ran, am encouraged.....klv


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## slotcarman12078 (Oct 3, 2008)

Great reading klv! :thumbsup::thumbsup:

I missed out of all this stuff as a kid, as my slotting history only lasted as long as the AFX snap lok track did (about 1 1/2 months)! 

Not to be a pain, but do you guys think this thread should be in "Tuning Tips"? I'll move it if you think so.


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## Boosted-Z71 (Nov 26, 2007)

KL this is a great thread, as a teenager I built several of these from standard AFX chassis long before magna-traction ever came along, however being a kid my building skills were pretty crude and most of the time things just were not right, I am going to dig them out again if I can find them and finish them now. I also have a 4 magnet t-jet that I built that deserves to be finished, thanks for all the work on the article and sharing.

Boosted


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## mowyang (Mar 24, 2008)

slotcarman12078 said:


> Not to be a pain, but do you guys think this thread should be in "Tuning Tips"? I'll move it if you think so.


I think this is the right forum for this thread. 
Great stuff, Keith! I enjoy any build that includes modifying pancake chassis. I remember reading your name in race reports back in the 70's, right about when you were probably racing chassis like this one. Welcome back to the hobby!


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## slotcar58 (Jun 21, 2007)

Great thread Keith! Great build! Build looks very similar to an enduro car that you built, we raced together in 1978 on Tom Hitchcox's first track! Glad to see that you are building again! Bob Dame (HOST) has reworked K & K bodies which would be perfect for this retro build. I can just see a Porsche 908 sitting on it! 

Leo (Rick) Belleville


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## K.L. VanAtta (Mar 23, 2009)

Everyone,

Part 4 has been finished (everything I wanted to say, must reread to check for lost words and grammar)....klv


An Interlude:


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## chappy2 (Jan 7, 2013)

Very Cool walk thru K.L., I got a chassis on the bench to give it a go this week.

Chappy


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## gonegonzo (Jan 18, 2006)

KL ,

Great article . I don't have the knowledge to have input but enjoyed and appreciate what you have done here . I also think you' might have inspired others to try this type of build and re-kindled others into finishing their "back burner" projects .

I hope you have more projects to come . That's what H T used to be about . This is refreshing after the latest trend leaning on the political and complaintive side . Thank you again .

Gonzo


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## K.L. VanAtta (Mar 23, 2009)

Good Afternoon,

Wow! Thank you to everyone who have left comments and those who have stopped by to see what this is about! In reading some of the posts it seems that my infamy has proceeded me (ha ha ha!).

Chappy2, Jim Hall fan? Happy to hear that you're going to give this a try!

Leo, How long have we known each other? Sorry, was not a fan of Randy's and George's bodies, but, bought tons of armatures. I would like to finish of all my builds for HT with Bob's bodies. Must send him an email.

Slotcarman12078, Never too late to relive your childhood (or be a child again in a metaphorical sense). Is this not a customization?

Boosted-Z71, When we all began our skill were crude. If we have the right mentors and teachers our natural abilities meld with our learned skills to create wonderful things. I don't know how many times I have begun again on a chassis!

mowyang, Thank you for remembering! May even do a pancake arm rewinding tutorial in the future. "Back in the day" we all wound our own.

gonegonzo, Thank you! I hope to take these pancake builds up to 1975-1976 national champion type cars sans the rare earth magnets and use polymer impregnated. Other improvements as well in electrical and tires; arn't Fray tires made for 1976 Unlimited Pancake car?

Of course there will be brass cars. This morning I laid out, on a sheet of brass, the central components of a "Bob Young" brass in-line chassis from 1970-71. Somehow Bob (a.k.a I can tell you) left the original with me in the mid 70's and steadfastly denies he is "Bob Young". 

Otherwise, from Riggens to beyond where Al Thurman is in brass. Al is another 40 + year friend of mine and I am SO IMPRESSED with the Land Shark line that I will by multiples of each.

Part 5 coming up I will post photos first and put in word over the next two days......klv


Part 5

Starting to hang the other parts on the chassis and turn it into a car. This first photo shows the disassembled components of the front axle. To me this is the standard, simple everyday front end setup; aluminum hubs, T-jet like front tires, cut to length spacers, and a 1/16th (0.063") brass tubing axle, all held together with big head pins.

Front wheels/tires of a HO size car are made to touch and roll, most rule books will clearly define this. Most rules also set a maximum width, currently 1 5/16" (1.3125"). I hardly ever exceed a width of 1 9/32" (1.28125"); why? I like clean passing (and racing) and on that rare occasion that I want to pass I can, goes for being passed too, I don't ever worry about tech in, and I don't think an extra 0.032" on an inch improves handling that much.

Other tips, round over the outside edges of the front tires this helps in general car dynamics. Think about this for a minute, what happens when a car enters a turn and rolls a bit, would you rather be on a sharp edge, box, or a rounded surface, ball? Use o-rings if you can if not you'll grind and size the tire yourself. 

Front axle slop I keep below the maximum. In this set up you gain the slop, lateral movement, by sizing the main axle x.xxx" longer than the width that you want; x.xxx" longer = the amount of lateral movement. This chassis/car has about 0.025" of lateral movement.











This photo shows the completed front axle assembly. Like I said, nothing ground breaking just what we did back then with the advantage of being nice and simple. Near the end we will be gluing the axle in place.











Here are the components of the rear end as I first ran the chassis/car. A G+ axle, a pair of G-Jet used sili-foam rear tires, and a Super II 19 tooth crown gear. All gave no clearance problems, the G-Jet tires are 0.450" in diameter and had enough life left to help set track clearance and make the first laps around my tiny test track. Looks like I need a tire between 0.405" and 0.420", dependent upon type, to get the clearance I want, 0.005" to 0.007".












That wraps up Part 5. I'll be back after I make some tires, grind some silicone, and do some experimentation......klv


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## ruralradio (Mar 11, 2011)

*Long live Bob Young.....*

_"......and steadfastly denies he is 'Bob Young'."_

The only man ever to run a 12 hour enduro solo in 11hrs 56m.


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## joegri (Feb 13, 2008)

klv thanx for posting yer "how to" for the magnatrak. i,d love to have more time to try this build. i will find time so time but? did you say brass in the future? ya got my attention now! i too am somebody that has seen yer stuff on different sites and always inspiring. this is what i mean bout time to build but,noooo i gotta go shovel snow then i,ll be wiped out to go n play in the cave! enjoying this build kvl:thumbsup:


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## gonegonzo (Jan 18, 2006)

I'll be looking forward to the Brass !

Gonzo


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## K.L. VanAtta (Mar 23, 2009)

Part 5 is finished....klv


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## K.L. VanAtta (Mar 23, 2009)

Good Morning,

Part 6:

Parts List:

AFX Rear Axle
Super II 19 tooth Crown Gear
JW's HoSpeedParts Rear Hubs 0.275" O.D. x 0.255" wide
Slade Brown's Sponge Donuts

Went through several sets of hubs and donuts until I found a combination I liked. Final size and notes on rear tires/wheels, tires are 0.438" in diameter with about 0.235" contact patch, the sponge feels to be a firm medium compound. This gives me a 0.010" to 0.012" rail clearance on the rear magnet and several hundred laps of racing.










The assembled rear axle may look a bit narrow, it is. Set at 1.27" the whole chassis will slide through the tech block. Reason for being narrow? Has a lot to do with my 1/24th racing days and how to get around the donut, transition to the sweeper, and on to the main straight of a Blue King. Think about a triangle formed by the guide pin and the outer edges of the rear tires and how that triangle would move when applying slot car forces to it; only applies to car that slide!

Thanks for looking.....klv


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## Bill Hall (Jan 6, 2007)

This is fun. Really enjoying reliving a build from the days of yore! 

Noted that you did not true the inside edge of the rear tire....yet? On a gravity sled, skittering across the rail in either direction is common. These days, I'm just fun running and using slip on silis for their durability and convenience; but I still dress a nice roll onto the back edge where the molding process ordinarily leaves them sharp and catchy.

Just curious....?


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## 22tall (Jul 28, 2002)

Here is an alternative to the steel armature plug. I made this out of Skulpty. It is nonmagnetic but will line up the mags.

I made this several years ago for another project I never finished. The original idea was to replace the standard mags with little neo discs encased in epoxy. Maybe one of these days...


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## alpink (Aug 22, 2010)

too too tall, that is a cool idea and available to more folks.
the idea of the plug is that it is just a tad over sized of a standard pancake armature and allows for shimming behind the magnets to ensure using the maximum capacity of the magnetic fields.
you already know that and are presenting options to those without a plug. good idea.
I have been trying to make a good mold of slimeline magnet spaces to do the exact thing you describe with Neo discs or squares.
had not considered the Sculpty for that application and now I have an option too.
thanx


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## K.L. VanAtta (Mar 23, 2009)

Bill, Thanks for reminding me.

22tall and alpink,

Thanks for the suggestion for making an air gap plug. In reality, if setting only the air gap, nearly any material, or item, will do. I have used an armature with tape wrapped around it to set air gaps at races in 1/24th and HO. In this build while air gap is important it is only one of duel primary reasons one needs to use magnetic materials.

The other reason is that this chassis uses the motor magnets to generate down-force to the track. To maximize the magnetic down-force the surfaces of the magnets need to parallel to the armature and parallel to the track. One way, perhaps the quickest, is to use a steel air gap plug and a piece of steel plate to set this.

Now, a factor that comes into play when setting the magnets is, how well the manufacturer cut the magnet. Most magnets will have a slope to the top and bottom surfaces of several thousandth of an inch, with the surface facing the armature being perpendicular to the leading edge of the bottom of the magnet. 

By using non-magnetic plugs the magnet will tend to align to one surface or the other, armature or track, diminishing performance. Using steel, the magnet tend to align to its optimum position relative to both the armature and track.

22tall, if you need a 0.700" steel plug drop me a PM. And steel plate too.

alpink, I assure you that no shims, magnetic or otherwise, were abused, injured, or killed in the making of this chassis. As checked by the National Counsel for the Humane Treatment of Shims.


Thanks for the questions and comments....klv


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## alpink (Aug 22, 2010)

:wave: ROFLMFAO :woohoo:


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## 22tall (Jul 28, 2002)

klv, you now have a pm.


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## ruralradio (Mar 11, 2011)

Tap, tap, tap..... this thing still on? Keith? Hello??


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