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Before attempting to build a full sized track, I followed the advice of several people who suggested to route a test track first. My "simple" design ended up using 10 corner sizes, ranging in radius from 10cm to 27cm, so the first tool I built was a simple "compass" to map these out on the 12mm MDF. Using a nail as a centre point. (HINT: hammer the nail into the centre point first, this makes it easier to find when using the compass) Then draw out the design so you can see where everything goes. I've used a 2B pencil as the width allows me to see the router bit underneath the guide.
Another trick I found useful was to draw the centre line on the router guide, and draw a line on the MDF where the router was to stop. Thus when the router came around I had a rough guide where to slow down with the route, rather than going too far.
When I started with the routes, I was using a strip of alluminium as a guide for the straights, as shown below. This worked fine for smaller straights, but I soon found that the pressure of me pushing and pulling the router caused the guide to bend in the middle from the force. Later I replaced this with a large piece of wood, secured at both ends with a quick release clamp.
As people suggested, I made mistakes. This was a good thing as I not only learnt to test the router position before making the cut, but also learnt that liquid wood is a good problem solver. I also found that the straight wood was problematic to line up. It was a case of inserting the router into the end of the start curve, pull wood tight to router base, clamp. Insert router into the end curve, pull wood tight, clamp. When remeasuring, because only a small portion of the wood was used, and the clamp was at the end of the table, it would need to be unclamped and then reclamped. To overcome this, I'm intending to make a jig which sites inside the route and is the same distance from the wood to the router so both ends can be matched at once.
My second mistake was trusting "Tomy". In the design pages I measured the distance between the middle of the hairpin curve and the squeeze tracks, to think that I could make squeeze sections on my test track the same distance. However on closer inspection the distance from the rail to the guide slot changes on both of these items, so is not equal to the majority of track. With my squeeze sections, this caused a conflict of the rail position (see picture below) between the two tracks.
With the problem above I can resolve this one of two ways - (1) Start again, (2) decrease the distance between the guide and slot rails in the squeeze sections. The good thing with this test is that (as stated at other places) MDF has two sides, so I'm opting for flipping the board over and starting afresh. Some of the mistakes I made have given me great insight into how to fix these problems, and I was quite surprised how easy it was to route once I'd changed some of my techniques.
As mentioned above, I decided to flip the board over and start again after the problem with the guide slots being too close. I fixed the compass guide holes to give some extra space between the tight sections of the track, and made the same modifications to the router compass jig.
I also made a small 'jig' for spacing the router on the straights. It was made from a couple of spare bits of wood with nails hammered in. One of the problems I found in the first build was that when lining up the router for straights, you'd measure one end, clamp it, go to the other end, clamp it, go back to the first end and it was out by 1mm or 2mm, this is because I was using a small portion of the guide wood, and the clamps were out at the edge of the wood. So these little bits of wood saved a lot of mucking around!!I also modifed the vacuum attachment for the router to fit on my vacuum by creating a small notch where the end of the hose clamps onto the router section.
Chopping or folding a business card up kept the slot clean when fixing with liquid wood, fortunately I didn't have too much of this to do between the corners and straight areas.
Another thing I discovered this time around was that wrapping a business card with sandpaper made an effective "slot cleaner" as shown below.
A picture showing the slots after cleaning up with the sandpaper.
For some reason my clamp decided it didn't want to grip as well as it should do, particularly on the longer straights. I think this may also have something to do with the fact that the guide wood I was using for the straight slots was thinner than the wood I used last week. Adding a secondary clamp to the offending end solved the problem, and a good douse of liquid wood cleaned up the problem routes.
I moved the "squeezing" S bend inwards about 5cm as I found it was easier to match a straight to a curve than matching two curves together. Another trick I found useful was (on a straight) to release the power on the router about 3cm before getting to the corner that you're getting to, and let it wind down as you're still pushing it along. Seemed to make a cleaner cut and I wasn't so plagued by the router "jerking" into a free cut, thus trying to make another cut in the corner.
Round 2 is looking better, most of the slots are clean, just waiting for the liquid wood to dry and give it a sand over, then start on the power rail slots, don't forget to wear a mask as the MDF creates small particles which had me coughing for a long time after the first attempt.
I opted to paint the track prior to routing the rails as others have stated problems with the paint getting inside the routes, which cause problems with laying the rails later. We had some spare paint left over from our recent house renovation, so it's a colour called "brushed sand", which looks like an off-white.
Unfortunately the paint got in the slots, and has caused a rough surface around the slot-area which may cause problems for cars to get around. I've used the sander to give it a fairly thorough clean up, but the cleaning of the slots caused me some problems. The paint is very tough so sanding has taken ages; about half hour per 30 cm. Working on that I'd be looking at around 160 hours of work to get them cleaned out!! On my next idea I grabbed the router and set it to the lowest speed and gently pushed it around the inside of the slots. This worked OK for the straights, but on the corners it followed the paint rather than the route. I decided to leave this until next weekend to solve, as I was feeling a tad under the weather.
This weekend I attempted to get the paint out of the slots - to give an indication of how bad this problem is, I attempted to push a Tomy slot car through the routes, and could probably push it 5cm (2 inches) before I would have to pick it up, move it forward a centimetre and start again. In other words there is a lot of paint in there! I first tried using my sanding technique, but found the small surface area inside the slot caused a lot of sanding back and forth with minimal gain. I then set up the router again, and ran it at both low and high speeds; even after three times through the same area, I was still not able to push a car around without drama. Trying to clean up with a Stanley type knife was not alleviating the problem any either, although it helped, it was a slow and long process. The photo below was taken after all three techniques were tried, showing how the slots were affected.
After around 4 hours of battling this, cleaning, routing, sanding, cutting and verbally abusing the paint and MDF I had cleared out a small section to a sub standard level. There was no way a car was going to make it around this track under it's own power as I could only just push it around the track.
I did have some success this weekend, however, in the form of some cheap foam brushes and some second hand paint. I'd picked up these brushes from the local hardware store for the grand sum of $au0.70 for three varying sizes, and a 250ml can of paint for $au1.50. Trialing these on my first test track gave a much better result to the surface, with far, far less paint going into the slots on my original test track (and the colour of the paint is probably a bit more "track like").
Trying the same technique with the "brushed sand" colour paint, the result was more satisfying, however it still got into the slots and would cause some work (although not as much as I am currently facing!!!). With the second track I estimate about 80% of the track needs to be reworked, whereas using this foam brush method, probably 1-2% of the track would need fixing. This sounds like a better option to me!!!
This last shot shows a close up of the slots, showing how "clean" the painting was. I also played around with a "two tone" paint job - I may incorporate this into the final design of the track.
Well, this painting debacle is going to cost me a lot of time, so I'm electing to start on the third test track. The good thing about this is the practice I am getting is invaluable, and MDF is fairly cheap (the sheet for this first trial cost me around $au10 - for this price I could buy few AFX pieces). This sheet with test track one and two will likely be cut up into breeding boxes for our Lovebirds. On another positive note, I also want to route the underside of this test track for power wires and timing gadgets; with track 2 I was always dubious that there may be a previous route in the way, or something else may cause me pain. So onto test track 3 .....
During the week I drew the track on the next sheet of wood, and spent a couple of nights in the garage while routing and working on it. I'm glad to say that on my third time around, I'm a lot better at getting the routes to meet successfully. The trick here seems to be to stop a corner just short (half a centimetre) of where you think it will stop, then get the straight to meet it. I've also found that there is generally more joy when routing the ends of the straight first, then routing the main portion of it secondary. On the subject of routing the corners with the home-made trammel, it's good to double check the entry and exit points, to make sure they are roughly correct.
After the routing was finished I cleaned up the board a bit and gave it two coats of the grey paint via the foam roller as discussed in earlier parts of this document. The result was good, although some extra work was required to clean the slots again (but nothing like the previous problem!!).
One minor modification I made to the design was to change the 'S' section of the design, so that the squeeze was removed. I'm sure the squeeze section on this track is overutilized; although this will only be a test track (as opposed to a race track), modifying the design means there are extra places to pass when two cars are run.
The next stage is to route the rail sections and then lay the rails themselves. With the paint in place, this seemed harder than I remember from the first test track; I also suspect my router bit is getting blunt from all the MDF I've been putting it through. along with trying to route through the dry paint from test track 2.
The first part of this was to test the rail depth. On test track 1 I'd got this pretty well correct, so I pulled this old track out and set the router depth to the same as this. The photo below shows the depth of the rails on this track, from as much of a side view as I could get. This rail is just sat in there for testing, so a bit of a kink in the track is apparent.
As I mentioned previously the paint in place seemed to cause some grief for cutting the MDF, as it seems to have held it in place better than the free wood. Even with the vacuum picking up the pieces after it, the router caused a bit of a mess, as shown in the photo below. I've super-imposed a picture with just a backlight to give a feel for the scope of the problem. I think in the final track I will be routing the rail slots before giving paint to it, I would even consider railing the track prior to painting, as the rails are metal, and rubbing them off (with a damp cloth) after the paint is down would remove the paint from the actual rails.
With this problem, I found that the best way to resolve the issue was to go around with a screwdriver and take the residual wood out of the rail routes this way. Then clean up with some light sand paper, including my "sand paper around a business card" trick. This was tedious and time consuming, as the router would "ride" on these extroneous parts of the route, which interfered with the true depth. So I'd route about 20cm, clean up, sand, then route again.
A problem with my jig also slowed me down this weekend, the nail in my guide jig decided to give way and stopped it from accurately going around the track. Whilst this was fixed with reattaching it and a quick blob of superglue, while waiting an hour we had some surprise guests turn up, which ended the track building for this week.
A point to remember is never leave the superglue on the jog, as mine leaked and stuck to the jig!!! I was fortunate that a screwdriver removed most of the tube, and it hasn't affected performance.
This is a preview for the lane spacing, showing a view down the main straight.
A few more hours work and the second lane rail routes are almost complete. I'll probably route over them again to try and maintain a consistant depth (and thus rail height when they are laid). When the waste from the router is flying around, even though the vacuum is attached, a fair amount is going inside the slot guide route, which is causing two problems. The first of these is the router guide is pushing all the excess along as it goes, when it gets to a certain point it will either ride over it (changes depth of slot) or stop the router from moving forward.
I'm fairly happy with the way it's going so far, so the plan at the moment is to clean up the rail routes, somehow check their consistancy, then locate where the control box will go, drill a large hole for the wires to come through, then drill some ~1.58mm holes to poke the rail wire through, and route a channel from these four holes to the control box. After this I'll touch up the paintwork then lay the rails down. Then test and finalize the wiring.
Someone on the bulletin boards (jimbo-slot) was asking about specifications for the slot depths. My plunge router is fairly inaccurate, and I've found a lot of inconsistancies with this as I look closer at the track. If I were to do it again, I would suggest "locking" the router down to a certain depth - I think my mistake here has been that I set the depth, and then "plunged" the router manually. This requires physical force both downwards and sideways under these circumstances, and whilst I paid attention to the incoming and outgoing slot (the connections between round routes and straight routes), the depth during these parts tend to be a bit sloppy. I would suggest for anyone else, as I will do in the future, to route the connection sections, then lock the router at the correct depth before routing the rest of the straight/corner. This should maintain a more accurate consistancy. In response to the original question, the guide depth is between 5mm and 6mm, the rail depth was measured by using the original test track and routing, then measuring the wire depth. The wire is 1.58mm round, and the slot depth is about 1.5mm. Once again I found the lock on the router was useful for consistancy here, although the paint on the track required me to go around about 3 times to get the depth the same all the way around.
The control box will be located in a corner on the board; this will have two 1/4" plugs for the controllers, a power inlet for the power and a 5 pin 180° socket for the timing portion of the track.
These holes will allow the rail wire to go from the topside of the board to underneath, where the power will be connected.
The underneath of the board was routed (badly) for the wires to go from the control box to the section on the track.I was originally going to use hot glue to keep these wires in placve, however I'll probably now use that to "tack" them down and cover the whole area with gaffa tape to keep everything intact, and prying hands out.
I patched some holes where the router bit and pencil had been pivoting. On this third attempt I was fortunate to have no routing mistakes so the patching was limited. Afterwards I gave it a quick coat of paint and sanded back to match the rest of the track. I also used some paint pens to mark the two lanes all the way around, electing to use the rail routes rather than the guide slot, which would be normal practice. Routing your own track can afford you these little changes to standardization.
Then rails started, unfortunately this wasn't as succesful as planned. The rail routes still seem about 0.5mm too wide, adding glue to the route didn't seem to help. I glued (polyurethane glue), laid a rail, then added some weight on top, all of which still didn't help. My "rail laying wheel" in the photo seemed to hold more in one place and create a groove in the wheel, rather than rotating and helping lay the rail.
I posted this problem to the and got two suggestions back - one was to insert slight 'kinks' in the rail and the other was to sand the underneath of the rails. I'll be trying this in the new year.
It's the begining of December, and I fear my time for the track is running out this year. We have overseas guests arriving in around two weeks and then Christmas will take up a fair amount of time. So I might have to clear up the garage and continue next year.
At the end of December, I got married, we then embarked upon a long holiday/honeymoon, thus the break in this construction. I must admit I feel like I've been slack, and finding it hard to get motivated back into the build of the test track, particularly as I've read more and more on the web about the overly magnetic properties of "round wire", which was what I intended to use on this build. I may contact Craig Jones, who is building the "Vortex 2" raceway (see links section) in Sydney, to see if he can post some sections of wire over. Craig went to the trouble of taking a large sheet of 0.4mm think steel sheet, and cutting it into 2.8mm strips. Just meandering thoughts at the moment. Need to get more constructive.
After having left the test track for around 6 months, and feeling guilty most of the time for not doing more work in the garage. Our group has discussed, upon occasion, the merits of differing rail types for a routed track. From what I can gather we have a few options, which roughlt fall into these categories:
Round Wire: The round wire is known here in Australia as "Farm Pak Fencing Tie wire", used on farms to keep livestock in; it's very cheap (200m for $au20) and fairly readily available at Bunnings and other hardware stores. One of our members made a test track using this wire, which was initially what I intended to do. However when I discussed this with him, his comments were that the magnetic downforce with this method far exceeded the requirements of the Tomy SG+ type car. His comments to me were that the trigger was held down with no requirements to 'back off' at the corners.
Flat Wire: I got in contact with Craig Jones (who is building the Vortex Raceways 2 in Sydney) to see how his track was going. He purchased sheets of 0.4mm flat sheet steel which he then got sliced into 2.5mm strips. This will lay vertically in the slots, and is similar to the rail inserts that Tomy would have used for their plastic track. The reasoning behind this is to trial both the "round wire" and the "flat wire", as I have heard the first gives far too much magnetic grip, thus taking away the challenge of racing. Upon contact with Mr. Jones, it appears he is having some trouble with the consistency of the cut for the rails - he cited that there is a marginal difference between some of the rail sizes and is currently (at June 2007) sorted these out to their varying heights. With the smallness of the scale, inconsistencies that seem minute can cause great drama to a slot car screaming through the track, causing a great deal of grief if you are running a "hot" motor which can reach real speeds of around 100km/h (about 60 mph).
Fish Tape: This was a solution suggested by Kevin Shaw from Full Tilt Speedways (see links), which is the method he uses for his tracks. Fish tape is an electricians tool - designed for gathering wires at the end of a conduit and dragging them back through. It measures 1.6mm x 3.2mm (other sizes are available) and is made from steel. The benefits of this is that the edge is rounded, giving an edge similar to the round wire, however it also has the same problem as the round wire with respect to the magnetic draw. I've heard mixed reactions from people on the bulliten boards regarding this wire - soem have said that it is great for non-magnetic cars such as T-Jets, others have said that using Stainless Steel versions of this medium produces less downforce for a magnetic car than the standard Tomy track. Regardless of this, I only found one source in Australia for Fish Tape (Radio Spares, in case anyone is looking for it), and they only had one type. Whilst the Fish Tape itself wasn't overly expensive, if it has to come from overseas then shipping could possibly be a larger cost than the Fish Tape.
Copper Tape: Copper tape is a solution employed by 1/32nd and 1/24th routed track builders. It has little to no magnetic grip and works well in those scales. For HO however, it requires modifications of the car to run, and suffers from the non-magnetism as per it's larger kin. There is a system called a "slide guide" which is distributed to make allowances for this, however it would require each member in our group to modify their car, and for no real gain in anything. Bill Brant (see links section as W. M. Brant) built a track in HO with copper tape, prior to moving to 1/43rd scale. I'd recommend reading his website if you are considering pursuing this track, as for a single racer it may not be the worst thing to do.
Braid: Similar to copper tape, braid works well for larger scales, and gives magnetism to the track, however, similar to Copper Tape, for the HO scale raceway, this is probably not the best rail. I'm sure it has been done, but modifications to the cars would be in order.
One other item I was discussing with Drew (who previously built a small test routed track) was heat and thermal expansion. When the current is applied to the rails, they tend to expand as energy becomes heat, and contract when they cool again. In a standard Tomy track, this is not a problem as the shorter pieces of metal have room to expand and shrink by overlapping with the next piece. I'm not sure whether the surface area plays a part in this, as a 1.6mm round wire will be about 2.01mm at any given point, whereas a piece of flat wire 2.5mm x 0.4mm will be around 1mm.
I've had some success using a flat wire called "Stitching wire" which has dimensions similar to the original Tomy track. My enthusuiam was waning a bit when trying the round wire, as it is far too grippy and would cause issues with high speed cars sticking like glue.
The friendly folk at CPS (see links page) sent me a piece of test wire - I'd initially asked for a 20cm sample, but they sent about a metre, which allowed me to build this straight. My construction techniques were similar to the tracks above, so I'll let some pictures do the talking here:
The dimensions for the broad flat stitching wire is 2.5mm x 0.5mm, whereas Tomy track is 2.4mm x 0.4mm, so it's a very close match. Made of galvanised steel wire, and coated with anti-rust material (according to their website and supporting documentation).
After the build, I hooked up some power and tested that the rails would conduct electricity; I also tested the magnatism for the track with the low-tech method of pulling the car up from both the test track and a piece of Tomy - everything worked and the magnatism was approximately the same.
One issue I ran into was the height of the rails - one of them was near perfect, but the other seemed to be moving up and down slightly. I removed the wire and re-routed this section, but the photo below shows prior to the second route.
After a week I took to the router again and ran it over the test track to get a more precise and consistant depth; according to Brad Bowmans site, he tries to keep his rail at an optimum of 0.012" (0.305mm) with a target of between 0.009" (0.228mm) and 0.015" (0.381mm) - he further states that the major manufacturers rail height varies between 0.007" (0.1777mm) and 0.020" (0.508mm). My depth was 0.017" (0.432mm) which is towards the higher end of the major manufacturers rail. Testing several cars on this showed that stock cars worked well, but lowered cars had slight problems. A close up is shown below.
One potential problem that a member of the HobbyTalk BBS mentioned, was the potential for rust on the stitching wire. For this I'm placing a raw piece of stitching wire in the weather, one in water, and a sanded piece (simulating rail degrading after a few races) in water. I've also done this for a piece of Life Like track to see what the results look like after a week.
Results of the rust test are below:
After 14 days of rust testing, the Life Like track seems a little worse for wear; to be fair this track is substatially older and has potentially been exposed to the elements before (this was an eBay purchase, so the complete history is not known):
After 21 days of testing, both tracks seem to be showing rust:
After 28 days of testing, both tracks seem to be showing rust in both the raw and sanded configuration:
Taking the original test track I started with a year ago, I re-routed the slots to a larger depth to accept the stitching wire; the router was set for the first round at the same height as I used for my test track, however after this I changed it to try and get closer to the magical 0.3mm rail height. I tested with the metre or so of left over stitching wire to see whether I had achieved this, however the rail and board were too far for my calipersto get a decent reading. Doing a 'hand test' by rubbing my fingers over the board the rail seemed to be just proud of the board, which is looking good. Still awaiting the 400 metres of wire to arrive, hopefully this will happen soon.
The stitching wire has arrived. Hopefully I'll get to lay it out this weekend.
Laying down the stitching wire was quite easy for the most part - the practice run I'd had on the piece of straight track certainly helped things along. However the first part of this journey was drilling through the track to allow a wire to be soldered to the stitching wire. I've chosen a smaller guage of wire than I will be using in the final track, as I consider that this track will bhe run with a standard wall-wart power supply. With the larger track I'm considering that I'll need to drill quite a larger hole as the wire is thicker.
After soldering, the wire needed to be trimmed and filed so that no excess was sticking over the top of the stitching wire; it also helps to solder the wire to the correct side of the stitching wire, although this is more of a cosmetic thing it looked better when I laid the second wire as I did this correctly.
Although the laying of the stitching and locking wire was relatively successful, there were still some points where the stitching wire sat too high from the board, and there were also some points where the locking wire would not completely go down, forming a bump over the height of the stitching wire. I'm not sure whether these are locations that I have missed when re-routing, or whether it may be dust that has got in the groove since the last time I worked on the track. I believe what is generally happening is there is a 1cm section which has not been routed (for arguments sake) but the wire moves up to this point, then moves down later, as you may be able to see in the following photo. I tried to use a small piece of wood and a rubber mallet to gently persuade these pieces to sit down further, but I believe it is something that is physically stopping this.
With the few minor hiccups of rail height, I carried on to connect up the power (via a Lifelike PS and controller) and give this a trial run; all was good with comparable magnetic pull to standard Tomy track, when testing a Turbo car.
I'm considering taking out the wire and re-routing the points which seem to be causing the problem - these have been marked on the board.
I put some videos up in our forum which are around 8Mb each, these are testing with a T-Jet car and with a Turbo.
After playing with this setup for a while, I came across another issue which affects certain cars, but not others. The distance between the rail route and the center route is about 1.1mm off, this creates a 2.2mm extra width between the two rails. I'm thinking that some of this may have been caused by the fact that the router bit is 1.58mm which was not compensated for when creatsing the track. In a straight this causes no issues with most of the cars, however when it gets to a corner, and in particular, a tight corner (as most on this test track are), the angle of the car pushes one of the pickups off the rail, as you can see in this image below.
These are some comparative measurements for the routed track and Tomy track.
The solution to this problems was to remove the wire from the route and re-lay it on the opposite side of the route (ie exchange the place of the locking wire and the stitching wire). I did this on the 'inner' lane for the two tracks and it seems to have solved the problem, however for my larger track, I'll be making another jig which takes this problem into consideration. I'm also contemplating buying a secondary router which I can have set at the power rail depth constantly, to save messing around with moving the large router small amounts to get this depth right.
Another issue that raised it's ugly head again was the problem of re-routing track after it has been painted. After I'd done some of the touch up work with the router to make sure the depths were consistant all the way around the track, it seemed that where the paint was on the top, and the router was out by a fraction of a millimeter, the edge ended up being frayed and thus pushed upwards. At some sections the MDF had pushed higher than the depth of the rail, so electrical contact between the rails and pickups was lost, and the car lost momentum. To solve this I went around the track and used a small pair of pliars to gouge away near the rail, then repainted the lane colours afterwards. It was slow work, but I seem to have got most of the problems ironed out, and most cars will successfully travel laps around the circuit now. Modified Super G+ seem to be the exception, the wheels cannot touch the surface, so sit there spinning (in certain areas or the track).
After thoroughly testing the circuit with a number of cars and a few beverages, it came time to address the electrics for the circuit. I posted a picture in the electronics section of some of the odds and ends that I bought to add the final touches to the track, in particular this will come to a junction box which will allow power and controllers in, and timing circuits out. Below is the photo of the box with it's physical mountings made, which was then wired to the track:
The next step is to trial the reed switches underneath the wood and make sure they work correctly. I've routed a deeper trough underneath for the reeds to sit in, and this gives about 2mm of MDF between the reed switch and the cars travelling above. The printer interface will be used, connecting to a 180° DIN type plug, which will be wired as per the diagram (from Lap Timer 2000) below.
After some frustrating trials with Laptimer 2000, and reliving the pain of using a soldering iron on really small parts, the track is mostly working with the reeds. I think that as a preference I will, next time, install the reed switches from the top of the track, rather than go underneath.
I've touched up some of the paintwork with white to signify the infields for the track.
Overall, I'm pretty happy with the way this track has turned out, and learned a few things along the way. The next task is to start planning and building the main track (after having a bit of fun with this one!!). I'm thinking of buying a secondary router, so that it can be permanantly set for the rail height, but eith way I will need to rebuild the lane spacing jig to the correct width, and review these notes before going forward. Firstly we'll be having another break overseas, so the next track will start after that.