Test Track Design

One of the most consistant pieces of advice I have received in my research is "build a test track first" - this is to work out how it all goes together, what pitfalls can be found, and what the success rate is like. I'll be using this as a test to see if I can guage the depth meter on the router. This seems to be the hardest part of getting this router to work, and is probably because I opted for the cheapest one I could find.

The test track will be to hone my skills in getting the track as close as possible to the fuul size track, and will be the design shown below, being a good test of corner making, marking the wood and resolving any issues which can occur at the build stage. This track will most likely end up in my study as a "test track" where I can run newly built or restored cars with the minimum of fuss.

I've deliberately incorporated some of the features I'll be using in the full size track, including "squeeze" sections, and a "box" to link the power, controllers and PC for timing software into the design. This is based on a design by 'jbromberg' in the Slot Car Illustrated forums (please see links section).

Go to the 'construction' part of this site to see how it turned out.

Routed Track Design

Looking around the internet more, trying to get some different ideas for the design, I started looking at routed tracks. The majority of people who had made these wooden tracks said that it wasn't as hard as they believed in the first instance, so I've decided to try to make one of these. This opened up a whole new world of possibilities; as I was no longer "limited" by the track which Tomy supply. In fact the people whose comments and posts I read said that once you try a routed track, you'll never go back to plastic. My next design was inspired by Kevin Shaw at Full Tilt Raceways.

The picture above shows my first design on a 1200 x 4200mm - although I'm thinking about making the "wiggle" section a bit tougher and banking the 180° corner on the right of this picture by 10°. I'm sure there will be a few more "personalized modifications" I make along the way.

The two photos below show Kevin Shaws' build, you can see these photos on his website, along with his other designs (please see Links section for his site address).

Plastic vs. Routed

There are two ways to go when designing a track, plastic (as supplied by Tomy, Aurora, et al) or routed. As always, there are pros and cons against both of these methods. I've listed a few here.

Plastic	Routed
Pros: Easy to set up and take down as a temporary track Can be setup anywhere After getting bored of a track, you can dissassemble and build an entirely different track	Pros: Cheaper to make Design limited only by imagination Distance between lanes is not set, allowing for more realistic racing Every curve can be a different radius Every curve a different duration Interesting gradient changes Squeezes to make things more challenging An optimum number of lanes "I built it"
Cons: Limited track design from pre-supplied parts Distance between lanes is pre-determined by manufacturer	Cons: Requires permanant location Cannot be changed easily

Lane Spacing

One of the joys of routing a track is that you are not limited by the spacing provided with standard track. Below is the standard spacing as provided by Tomy tracks

As you can see, there is minimal spacing for "drifting" between lanes 1 & 2 and also between lanes 3 & 4. As we drive one event at least which has non-magnetic cars I wanted a fair amount of space so that two cars could be going around one turn with both allowing a bit of space for the rear end to lean across the track. Below are two diagrams using a 20cm width for four lanes (drawn by Mike K on the ).

On another part of the track I was keen to have the lanes as close as possible to "squeeze" the cars together and not allow passing. This is a common theme on the 1/32nd car tracks which use this as a strategy point for slowing down faster cars (or for a faster driver to get past before being blocked). I turned back to Tomy to measure the lane spacing between both a 9 inch squeeze track, and the 3 inch hairpin corner. Both of these have a limited section of area which bring two cars closer together.

As you can see, the space between the slots on this track is approximately 24mm. I say approximately as the slots are generally measureed from the middle to the middle, however it was more practical to measure the closest two points of the slots.

It surprised me a bit that the slots in the hairpin were closer at approximately 19mm, shaving another 5mm from the width between slots. With this new information, I believe the width of my track, at the minimal point can be (3 x 20mm) + (2 x 32.5mm) or about 12.5cm at a narrow point.

The example below shows how another builder has used this technique.

Lane Colours

As per the "standard" four lane racetrack colours, they will be red, white, blue and yellow as shown below. Red is on the outside lane.

Table Top vs. Free Standing

I saw on another site a mention of this and thought I may go through some thoughts and considerations with the argument of "Table Top" vs. "Free Standing" raceways. Firstly, to define each, the first is generally a raceway which is laid out on top of a table, with the track overlaid to cover the top, using the table legs and the top for a place to store cars and miscellaneous items. The second is a raceway that has it's own legs, these generally don't have places to store cars and are usually found in larger establishments.

I'm currently leaning towards going from "benchwork", which is a technique employed by a lot of model railroad enthusiasts. This is half way between the two, as HO Is probably too small for a free-standing arrangement (this is usually employed on 1/24 and 1/32 scale tracks) and a table.

Tips and Tricks for design and construction

After speaking to so many people about building a routed track, I thought it was worth seperating the advice given and aquired from the net in this area. Some of these may not work for you or me, but the people I spoke to believe they are worthy of a mention. So I've archived them here.

Tony Kidson

Tony was one of the first people I emailled in regarding to routing a HO track. His first track can be seen from the links section, but unfortunately diasaster (in the form of water) struck before he could complete his second and main track. As well as giving advice on the , he handed me these gems of information via email:

Make a test track first; learn what can go right and wrong while using the tools.
Slot drill bits are acceptable substitutes for router bits.
CNC Routing may not be as accurate for slot depth as hand routing, due to the inherant problems with the base material.
Keep MDF dry; any moisture will spoil the surface prior to painting.
Digital Verniers are a must!

Kevin Shaw - Full Tilt Raceways

I called Kevin at his home in America. Shipping a track to Australia would be highly expensive, so he offered some good advice about building tracks, and, as you can see from his site (check the links page) his work is outstanding quality. These are some of the points he mentioned:

MDF is more forgiving than Formica, but needs to be painted to finish it off.
Amana Tools sell a true 1/16" bit in solid carbite for around $us16 to $18.
Make a pattern for the inside lane from 1/2" MDF and run the router around it.
Try to use the router enough to get a feel for the depth of the bit.
Try to cut as much of the track in one piece.
Make a jig to fit inside the primary guide slot for routing a secondary guide slot.
Don't try to make the corners too sharp as it will cause a problem for the wire and possibly not correctly route.
If you need to stick the rails down, use Gorilla Glue, or Elmers Ultimate.
The best wire is flat with a rounded edge.
When painting, avoid getting paint in the slot.
Make a practice track first!!!
A smaller "trimmer router" (around 2.5" to 3" in base diameter) is better than a larger model as it's easier to see what you're doing.
When complete, cut the track out with the router, as this makes a cleaner cut than a jigsaw.

Will Brant

Will has a MSN page which documents a lot of his sucesses and otherwise, this can be seen in the links section. However I also posted a message on his board and got some tips from him:

Don't be afraid. Routing isn't that difficult. Every error can be fixed.
Put a lot of thought into your design. I didn't the first time, and ended up with a track that was too difficult to drive.
Don't try to build the "world's best track" the first time around. Make something that challenges your skill (building and driving), but expect that you will want to replace that track sometime soon. Unleash you talents on the second track...

Slot Car Illustrated

I found these "Tips and Tricks" on the Slot Car Illustrated message board; these relate to 1/32nd scale cars, but some can be applied to HO:

Design

The biggest advantages to a routed track are that no two corners are of a constant radius and there are almost no perfect straights.
Squeeze sections are what makes it interesting. With squeezes a whole new level is added to the racing, bringing strategy and entertainment to your racing. Just don't use too many.
Adding small LED lights under the overpasses help with visibility.
Don't put the light sensors on a curve. The cars can slide far enough to trip the counter for the next lane.
2" minimum overpass clearance is required. 3" is recommended if 1/24th scale cars are to be run.
Overpasses should not be placed over curves, in order to provide maximum visibility for drivers.

Common Mistakes

Spend lots of time planning, and when you get a design you like, draw it out as big as you can.
Don't buy cheap router bits
Parabolic turns ... even when using a compass to lay out some corners, when it comes time to do the routing use the Lexan strip, it will give a smoother transitions.
Don't make it look like a plastic track.
A whole series of esses can be irritating.
Don't put squeezes on straights.
Leave ample passing spots between squeezes.
One tight corner is usually enough

Paint

There are a couple of common choices for paint:

Latex paint.
Chalkboard paint. Available at Home Depot (in Canada) for $15 Can per qt. Buy 2 quarts. And two quarts of oil-based primer (two coats. Don't thin the primer.).

Mix 1.5 to 1 (chalkboard paint to thinner.) with oil-based paint thinner (mineral spirits). It's fairly difficult to thin. Lots of gunky stuff builds up in the tray while you stir.
Paint it on the mdf with a wide brush, followed by light rollering (with a 4 inch sponge roller) to smooth it out. The paint needs frequent stirring, or it settles and gunks up in the tray. So every time the brush goes in, give it a stir.
Use 4 inch foam rollers. The paint eats the rollers, so discard the roller after each coat of primer or paint. Roll the paint in the direction of travel on the track. Prime the edges and the slots really well.
Chalkboard paint dries fast, but let the it dry for about two days before laying the copper tape.
A new track will always be slippery at first.

Routing

Wear masks! Routing is a sawdust nightmare! It is advisable that you have an extra person going along right behind you with a vacuum cleaner hose, sucking up sawdust as it is made.

Router Guides:

Once you nail down your guide, put the (unplugged) router in the existing slot, and turn the bit by hand to make sure it spins. If you do this at both ends of your cut, everything should line up.
When you try to match up the flexible strip to another curve, it's best to start back about 3 inches and work your way toward the end of the existing slot. It's a little tricky, but gets easier.
Lay out the track design (on the wood) using a compass and straight edge for most of it, then I do all the routing with the flexible strip, using the layout as a rough guide. Using only the flexible strip may take a little longer, but you'll get a more flowing track, and it will look more realistic.
Lay full sheets of MDF out on the workbench, clamp them down, and route across the joints. Cut out the roadway afterwards. After cutting out the track, round all the edges just a bit, too. Just looks nicer.
Wherever there's a straight section, give it a slight curve, and the entry to corners will be smoother. For elevations, route the slots first, then cut out the roadway, and then start blocking up areas and see how it affects the rest of the track
Try to start and stop the routing on a relatively straight section, makes it easier to line things up when you move the flexible strip.
DON'T cut anything freehand.
Never pull the router, always push. And push HARD against the lexan strip.
PRACTICE ON SCRAP FIRST.
When repairing routing mistakes, use a piece of 1/8 inch styrene sheet cut into a 1x4 inch strip; push the strip into the slot at the area that's too wide and fill in the area with Durham's Rock Hard Putty, and let it dry overnight. Wait till the putty has fully hardened, give the strip a tap to break the seal against the putty, then slide it out. Nice clean repair. Or you can fill the whole section and re-route after the Durham's has set.
You can also wrap sandpaper around the styrene strip to clean up some of the sloppy routing. Just slide it into the slot and sand.
Here's a major time-saver during the sanding process. Duram's seems to shrink into the holes a bit, sometimes requiring a second application. The alternative is to apply an excess of putty to the hole, which requires quite a bit of sanding later, after it cures. I ended up using the latter method, but instead of sanding, I used a small hand planer to remove the bulk of the Duram's, finishing with a quick run with the sander. I was able to do the whole track in about an hour. And that's fixing LOTS of routing mistakes, and more nail holes than I can count.
Use a two flute tungsten carbide router bit, rather than high speed steel.
Check for glue build-up on the router bit. A dab of turpentine will take it off.

Wiring

Use18 gauge 2-wire lamp cord for jumpers.
If you have 4 or more lanes, usually a good 0-20V, 10 amp power supply is good.
Power taps are necessary for longer tracks to prevent voltage drop.
Track wiring will include dynamic brake circuits.

Table Design

In my situation, I need to have a table which can be removed from time to time. The track will sit in our garage in the first part of it's life, and will hopefully be moved into our (soon to be made) patio/veranda area out the back. I've looked at a few others table designs and most of them haven't been well suited to my situation. While most people tout the design that Greg Braun has put on his site (please see links section) as "the" choice, I'm steering more towards a design which is employed more by model railroad people called "benchwork". A classic table is a series of pieces of straight wood, complimented with a full sized sheet on the top, giving the base for the track to sit on. With benchwork you are essentially removing that top sheet thus making the completed table lighter. This will be essential for me to be able to move the track, as it will not remain in one position for all of it's life.

I'm also thinking of making the legs in a removable fashion, matching the table where it joins, and adding a bench underneath for the essential racing items, such as timing PC and power supply.

Table Material

I'll probably go with pine as the basis for the benchwork, as it's fairly cheap and readily available. I suspect I can go to a scrapyard and pick some up at a bargain price too.