67 replies to this topic

[Alchemist]

I've always wanted to scratch build an inline chassis but I do not solder well.

 

So, I decided to build myself a "Retro Mod" chassis, using the inline configuration I grew up with, but with a twist.

 

As I was "imagineering" my concept, I decided upon using composite sheet as the base chassis material and fabricating the other parts with aluminum 6063-T5.

 

I had cut out a few dozen chassis designs with each and every one being revised, because it was crooked, uneven, or I did not like the design.

 

I started out with different sizes, but ended up selecting a .062" thick Phenolic G10 Composite sheet.

 

 

Here are a few of my recent chassis design pieces.

 

Thank you.

 

Ernie

[Alchemist]

I cut my "motor box" from 1" 6063 aluminum square tubing.

 

It's not too heavy, weighing in at 5.5 grams.

 

As a comparison, the forged brass motor bracket I purchased weighs in at 8.4 grams.

 

 

I then fabricated the motor box supports which connect it and keep in located onto the chassis.

 

 

Here is the motor box and the supports prior to assembly.

 

 

Thanks.

 

Ernie

 

 

 

 

[SpeedyNH]

nice. we have built eurosport chassis out of G10 f'glass single-sided copper circuit board.

speedy

[Alchemist]

Here is the final prototype chassis design with the motor box, supports, body mount brackets ( for wire clips), front axle mounts and guide tongue mounted.

 

The guide tongue is also composite.

 

[Alchemist]

Since my chassis is just for fun, and not intended for use in any sanctioned race, I decided to modify the guide similar to what I remember using when I first started playing with slot car in the 60's.

 

I'm using screws to secure the motor lead wires to the guide.

 

 

I found this FK180 motor with ball bearings in my stash of motors, so I decided to trial fit it.

 

I'll probably use this motor to test how the chassis works, once I finish up with the details.

 

Thanks for letting me share my first "scratchbuilt" chassis.

 

Ernie

[Alchemist]

I wanted to point out, that I decided to use the aluminum material for my motor box,  because it will also act as a "heat sink".

 

Thank you.

 

Ernie

[Geary Carrier]

Very cool Ernie...

[Alchemist]

That is very kind of you to say so Geary!

 

Thank you so much!

 

Ernie

[gotboostedvr6]

In case anyone is wondering
Thermal Conductivity [BTU/(hr·ft⋅°F)]
1 Copper 223
2 Aluminum118
3 Brass 64
4 Steel 17
5 Bronze 15

[Ecurie Martini]

Two (sort of) related points:

 

1. Anyone capable of the level of craftsmanship seen in this thread can quickly learn to solder competently.  The most common error that I see aside from inadequate surface preparation (cleaning) is too cautious an approach using an iron that is too small to get enough heat into the joint quickly (and then get out of there)  This leads to the typical lumps, bumps and blobs appearance of a poor joint.

 

2. The post above covers one of the reasons that I prefer to work in steel - its thermal conductivity is about 1/4 that of brass so the heat stays at the point of application thus higher local temperature and less spreading.  Steel is also lighter than brass and much stronger.  The downside? You need a good acid flux so careful cleanup is needed and, left untreated, it will rust.

 

EM

[havlicek]

Very cool Ernie!

[Bill from NH]

Ernie, you did a nice job fabricating this chassis & it's parts. It looks to be somewhat indestructible. It also might be a good chassis for rental car use too. I can visualize you making all sorts of other chassis designs using the same techniques. Maybe both 1/24 & 1/32.  What did you use to mount/attach the aluminum pieces to the phenolic? Did you use some sort of epoxy, or other adhesive? Let us know how this one drives.

[MSwiss]

Great job on the chassis.

It has a similar vibe as the below 3D printed one, Steve Grider designed and sells, on Shapeway.

I agree with post #10.

Your craftsmanship level is so high, your issue with soldering must be never having the proper iron or acid flux.

Guys always think they can get away with a $20-$30 iron from Home Depot, and rosin flux.

The difference between an 800 degree, and a 1000-1100 degree iron, is night and day.

Spend $65 on a Hakko 601 with a chisel tip, get some acid flux(Stay Brite, Lucky Bob, CR), and a small paint brush, and it's virtually impossible not to solder well.

[MattD]

This cured most of my soldering problems.   It does require a good washing when done to remove any acid residue.   I believe this to be what is in the little bottles of Lucky Bob's flux.

[JimF]

Two (sort of) related points:

 

1. Anyone capable of the level of craftsmanship seen in this thread can quickly learn to solder competently.  The most common error that I see aside from inadequate surface preparation (cleaning) is too cautious an approach using an iron that is too small to get enough heat into the joint quickly (and then get out of there)  This leads to the typical lumps, bumps and blobs appearance of a poor joint.

 

2. The post above covers one of the reasons that I prefer to work in steel - its thermal conductivity is about 1/4 that of brass so the heat stays at the point of application thus higher local temperature and less spreading.  Steel is also lighter than brass and much stronger.  The downside? You need a good acid flux so careful cleanup is needed and, left untreated, it will rust.

 

EM

 

+1.....couldn't have said it better.  Nice work Ernie.

[Half Fast]

I believe Lucky Bobs flux  is sulfuric acid which is not the same as Stay-Clean.

 

Cheers

[Dave Crevie]

I designed and built this wing car chassis about ten years ago. The material is RAM, radar absorbing material,

used on the skins of F-117 Stealth fighters. It was designed in SoldWorks, and I used the stress analysis to

arrive at the torsional property I wanted. The motor box are is spring steel, and bonded and riveted to the

chassis substrate using the bonder that is used to attach the RAM to the fighter's outer surfaces.

 

Sadly, the car was never competitive with the big boys, in any of it's configurations, so I abandoned the

project.

 

 

 

[Alchemist]

My Brethren,

 

Thank you for the kinds words and inspiration!

 

 

Hi Dave,

 

That is a very cool chassis, and for me, it's such in inspiration in design!  How did you acquire that awesome material - legally?  LOL!

 

 

Bill from NH said:

Ernie, you did a nice job fabricating this chassis & it's parts. It looks to be somewhat indestructible. It also might be a good chassis for rental car use too. I can visualize you making all sorts of other chassis designs using the same techniques. Maybe both 1/24 & 1/32.  What did you use to mount/attach the aluminum pieces to the phenolic? Did you use some sort of epoxy, or other adhesive? Let us know how this one drives. 

 

Hi Bill,

 

You are correct in your observation that the phenolic is virtually indestructible.  I'd like to share a story in regards to it's "durability".

 

Approximately over 10 years ago, when I was starting to get back into 1:24 slot car, I had purchased a few different brands of angle motor stamped steel slot car chassis, along with low cost motors and a Parma controller.  

Trying to redevelop my "hand-eye coordination) while relearning to drive, and coming to the realization, that when you crash, the chassis will bend, and beyond my skill level to repair!

 

Having worked with composites and alloys as well as custom painting, fabrication and body repair, (I was a design engineer in automotive restoring of vintage race cars/mods to current race car, and other high dollar collectable cars) I figured I would make an attempt to fabricate my own chassis.

 

Having discovered "Slotblog" back then, it was a thrill to view the many scratchbuilt chassis projects of the brethren here, and still is my source of inspiration.

 

Now, back to how indestructible, phenolic composite can be.

 

My first anglewinder prototype consisted of .032" thick G10 phenolic, and since I had a few chassis's that, to me, were no longer usable, I cut off the rear motor/axle mount and stuck it on my chassis design.

 

Here are photos of my initial prototype.  To this day, every thing is hand cut and filed to shape.  I would like to acquire some equipment to  make it easier but I find it satisfying to fabricate "old school".

 

 

The motor was built by our own "Sir John Havlicek", and I must say that I'm privileged to have a handful of custom built motors from him.

 

with body mounted:

 

 

On my first test, I wanted to see how it would survive a crash.

I live in Vallejo, CA - and Eddie's Slot Cars has the Blue King Track.

I ran full throttle on different parts of the track to intentionally crash in a variety of ways.

The most severe crash was at the end of the straightaway.

The other racers initially scoffed at my design and when everyone heard the big crash - someone sheepishly yelled "back to the drawing board" amidst a bunch of laughter.

Well, the only item that had come loose was a body wire clip that I just clipped back on and placed it back onto the track to keep testing.

I had quite a few inquiries after that incident, because they figured with such a big crash, the car would be totaled.

 

I was inspired to continue developing my composite chassis.

 

I would like to share the remaining prototypes of my anglewinder composite chassis's and my own custom box I keep them in.

 

Here is my box that I made from aluminum/polyethylene composite sandwich board and vinyl wrapped. 

The cars  on the shelves are all the anglewinder prototypes running Sir John Havlicek's motors. 

 

 

I made the handles from RC Car wheels and tires I had laying around and even fabricated cross-drilled steel rotors - made from steel washers.

 

 

This particular chassis, on the Blue King, with me driving, started out on the first lap in the mid 8 seconds.

After many more laps (after the many crashes LOL), and getting acclimated to driving it, eventually dropped down to my best of low 6 second laps.

 

A couple of fellow racers asked if they could drive it and I shared it with them.

One racer, after only a few laps, immediately was running mid 5 seconds laps.

The other racer was able to hit consistently 5.0-5.1 second laps, after having rubbed some traction compound on my tires and placed some weight on the front of the chassis.

 

After a little discussion, it was determined that my Parma controller was the problem because it could not handle the power from Sir John's motor.

 

I felt that it wasn't just the controller I was using - I just can't drive - hahaha!

 

The two racers had the more sophisticated controllers - they might have been Third Eye controllers or something equivalent.

[Alchemist]

What did you use to mount/attach the aluminum pieces to the phenolic? Did you use some sort of epoxy, or other adhesive?

 

I use 3M VHB RP Series Bonding Adhesive Tape; the VHB stands for "Very High Bond" while the RP - to me - stands for "Really Pricey" - because it is!  hahaha

 

I employ the RP16 Series, which is 0.016 in  thickness for my application.

 

I find it to be an excellent product for mounting my aluminum pieces to my phenolic chassis, and applied it to my slot car prototype chassis for over a decade now - though I have used the 3M VHB tapes for over 4 decades in the automotive arena.

 

This is considered an adhesive carrier, which is basically a foam core, permanent bonding, double sided tape adhesive.

 

After 72 hours of dwell time (letting it sit prior to putting it to use) it basically "welds" itself to the substrate and extremely difficult to remove without damaging your part!

 

Here are some details:

 

• Fast and easy-to-use permanent bonding method provides high strength and long-term durability
• Virtually invisible fastening keeps surfaces smooth
• Can replace mechanical fasteners (rivets, welding, screws) or liquid adhesives
• Eliminate drilling, grinding, refinishing, screwing, welding and clean-up
• Creates a permanent seal against water, moisture and more
• Pressure sensitive adhesive bonds on contact to provide immediate handling strength
• Allows the use of thinner, lighter weight and dissimilar materials
• Resists solvents - even sea water
• Temperature Resistance: Short Term (minutes, hours): 250°F (121°C) Long Term (days, weeks): 200°F (93°C) 

[Alchemist]

To determine the strength capability of the 3m VHB RP Series Tape, I used it to mount my rear wing mounting brackets to the rear tailgate glass of my daily driven wagon.  

 

This is a picture when the wing was initially mounted over 2 years ago.

 

 

I fabricated the wing supports out of 1/4" aluminum/polyethylene composite, while the glass surface mount brackets are made from steel.

 

The RP series tape is employed to the bottom of the steel brackets which is adhered to the glass.

 

I get a lot of questions on how it's mounted - some people have asked if I drilled through the glass.

 

 

Here is a picture taken today as the rear wing brackets still sit firmly in place, never removed, never getting loose,  having been through rain storms,  100 degree days of the summer, and the winter cold.

 

The wagon looks different now becauseI painted the car in the garage more than a year ago.

 

 

To me, the RP Series bonding tape is a phenomenal product.

 

Thank you.

 

Ernie

[Bill from NH]

Ernie, thanks for providing the above details.

[Alchemist]

Hi Bill,

 

Thank you for your inquiry!

 

Ernie

[Bill from NH]

I  have another question on the first chassis shown above. With the 3M tape being so strong, why didn't you tape the guide tongue to the chassis? Or did you tape it on, then added the two screws for reinforcement? Eddie's raceway was Rick Thigpen's home raceway before he moved to Oregon. i would expect your phenolic chassis would run nicely on Eddie's flat track too. Both Eddie & his wife are originally from CT. I used to wonder for years what you actually did in slot cars from reading your posts. The photos that you've posted above show the high level of your craftsmanship. Now I'll stop wondering.       

[Alchemist]

With the 3M tape being so strong, why didn't you tape the guide tongue to the chassis?

 

Hi Bill,

 

Yes,  I did and have always applied the RP tape under the guide tongue. 

 

The screws were an aesthetic afterthought.  They aren't required.  It's just that  I have a bunch of these wafer head screws and just wanted to put them to use.

 

My final version of the inline chassis will not have the screws.

 

My other anglewinder chassis's had  survived many crashes using the RP tape, without coming loose/off/cracking/breaking,  and that is without the front crash bar design that is employed with my current inline chassis.

 

With the front crash protection bar intended to protect the guide flag and tongue, I do not believe I need to worry about it's integrity.

 

 

Eddie's raceway was Rick Thigpen's home raceway before he moved to Oregon.

 

It was always a pleasure to see Rick T when I use to visit Eddies.

 

He would test his newly finished projects, as well as the other cars he built.

 

To see Rick's project pictures on Slotblog, is always a treat, but to see the cars he builds in person, is indeed an experience.

 

His home track is gorgeous!

 

I'm planning on building a track for myself in the near future.

 

 

I used to wonder for years what you actually did in slot cars from reading your posts.

 

I've had more than a few inbox inquiries about whether or not I had anything to do with slot cars etc.. , other than posting on Slotblog.  LOL

 

Viewing the craftsmanship here on Slotblog, displayed by the many talented and renown members, is such an inspiration and motivation.

 

I had never posted any of my slot car projects, because I was too ashamed that my skill level would not  even register on a scale!

 

It's been over 10 years now, and here I am, finally coming close to completing a project, wanting to share it;  in the hopes that I would  not be too ridiculed/criticized, because of the different path of my project and workmanship.

 

So, I would like to express my "Thanks"  to everyone,  for the encouraging and kind words.

 

It is appreciated!

 

 

Ernie

[Alchemist]

 

MSwiss said:

Great job on the chassis.

It has a similar vibe as the below 3D printed one, Steve Grider designed and sells, on Shapeway.

 

Hi MIke,

 

Steve's chassis, since your initial introduction a while back, is one great chassis.

 

I purchased one to have on hand and it's gorgeous as well as ingenious.

 

It's another "custom designed" chassis that inspires me.

 

Thank you for the kind words Mike!

 

Ernie