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Discussion Starter · #1 ·
Building the Stoney Mountain Quarry Stage - Part 1

It all started with a move around in the Manx Slot Car Club room. The roof is leaking in certain areas, and the floor and carpet are wet. Unfortunately a small test track that Dave Capelen had brought in had been sitting on the wet carpet and, as it had a surface made from chipboard, one of its edges had swollen and become unusable. I asked Dave what he was going to do with it, and he said he would probably never get round to repairing it, so I asked if I could take it off him.

That was the start of my new rally stage. I had always liked this small piece of track, and the way it had been decorated, so decided to add what was left of it to a new rally stage I would build. A more experienced track builder advised me against it, but I ignored this advice because I didn't want to see the track wasted. In hindsight I've got to agree that Mike Buss was right!
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It took me almost as long sorting that section out as it did to create 3 brand new sections!

I started by drying it out, stood up against my lounge radiator, and then studying the section and working out how I could cut the swollen part off, and leave the rest of it in a stable condition. I added a few sections of wood to strengthen it prior to cutting, and when I was happy enough drew a pencil line where the track still looked solid, removed a couple of screws that were in the way and began cutting with a handsaw. My Grandad did a lot of joinery and taught me well, so it ended up pretty straight. The photos show some of the swollen bits, and the underside of the track section where I added strength (the newer looking wood).

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The next thing to decide was how large to do the stage. I decided to add 3 sections of MDF sized 2ft by 4ft. I'm showing my age here with the imperial units! It converts to approx 1200 x 600mm x 9mm thick. This would mean that I could easily transport the sections in a car.

Once I had those, I strengthened each board, on its underside, with 2 inch by 1 inch (50x25mm) pine, making sure each edge lined up with the edge of the MDF, to make for accurate joining of the boards later.

Then I laid out some large sheets of paper over the top so that I could draw the layout. I used 3 different sizes of plates and the bottom of a kitchen roll holder for the different radii of curves I wanted.

If you do irregular curves (2 or 3 different diameters) then you have to carefully blend the curves into each other to keep things smooth.

I soon found out that the paper was actually the wrong way to go; I should have drawn it straight onto the boards, as in the end I had to transfer it from the paper onto the MDF, which was no easy matter. Anyway, by doing that, I had to find out where the radii centres were, to create the curves. This was something I knew I would need for the routing later on. I put a small circle around each of these radius points for future reference.

I also marked the start and end point of each of the radii. This would prove very useful when it came to doing the routing. I ended up with about 6 different radii, 65mm, 70mm, 85mm, 100mm, 110mm and 140mm used in multiple areas. Remember, for every different radii you have you will need to adjust the router setup, so use them multiple times rather than having loads of different ones that don't really make much difference to the track layout.

The photos show my original pencil sketch, and then a view from above on the final layout put onto the sheets of paper.

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I then added a triangular piece to the old section of track, so that it would match up with the new sections, which were slightly wider. Again, this took a bit of messing to get everything lined up.

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To be continued ........
 

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A trick that I used on the latest track that I built was to put a strip of alloy across the track adjacent to the joints between boards, to help prevent warping. The alloy strip is sandwiched between lengths of timber and pinned in position with 8mm dowels. The dowels that you can see in the photo are the ones that locate to the two sections together. The dowels that pin the alloy and timber sandwich are hammered in flush with the framework.

Time will tell how well this will work.
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Kevs Racing Bits
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I saw that original small rally stage, it was very bloated with water, I'm really pleased you kept most of it.

...I'm really looking forward to driving the big Rover SD1 on it
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Be careful with the small radii!

There are several tracks that were used during the Slot Rally GB series, that are quite hard to drive due to the severity of a couple of hairpin bends. This was largely due to guides getting " wedged" in the sharp turns, meaning the car would stop then the wheels would push the car out of the slot.

I don't recall who told me, but I was once told that the smallest successful diameter of curve for 1/32 was equivalent to a compact disc. Without going to measure one, I'd guess that's about 100mm.

It might be worth routing the smaller diameters in a bit of scrap first to see how bigger guides pass through the slot.

Simon
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Tightest curve that I have used has a 1.5 inch radius on my "doughnut" "track" but for a rally style tracks I would say that a 4 inch radius is about the tightest that you can go. Remember that you have to get the tape to lay flat, unless you use braid.

 

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Kevs Racing Bits
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Looking at the Porsche on the layout I'd say the tightest corner is about 55-58mm radius.
 

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Discussion Starter · #8 ·
Hi guys, thanks for your comments. As I said in the original post, the tightest radius is 65mm, which I know works, as I measured it on another track I've seen and used. A compact disc is 60mm radius by the way, I've just measured one
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For fitting the sections of track together I have cabinet makers dowels and toggle catches, which is a method I have used on my one previous stage, which I had a lot more help with. I'm not finished, but I'm actually further on with the build than the story written so far. I just haven't had time to put it all in a post yet, so I'm writing it in a few parts. I made mistakes along the way, so I'll mention those, so that anyone reading this, that hasn't done a build before, can hopefully avoid the same ones.

Some of the members of the Manx Slot Car club seem keen to build their own rally stage, so I thought I'd write it down in a bit of detail to help them get the confidence to have a go themselves.

If I get chance I will post more tomorrow.
 

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Discussion Starter · #9 ·
Building the Stoney Mountain Quarry Stage - Part 2

Now for routing the slots. Fellow Manx Slot Car Club member Mike Buss kindly volunteered to help me, so I took all sections of my track up to him, where we could use his newly cleared out garage.

The first job was to lay out all the new sections upside down, on a flat surface, so that we could bolt them together, leaving a flush track surface. 6mm bolts were used to initially hold them together, as well as washers and butterfly nuts. Then, holes were drilled to locate the Cabinet Makers Dowels. Two were used for each join. These provide a positive location when joining the sections together.

Then Toggle catches were added to the side of the sections, these pull the sections tightly together, and are really easy to fit and to use. I made the mistake of purchasing short ones, next time I would purchase longer ones, as this gives you 'more room to manoeuvre' when fitting. Once these are fitted, then the 6mm bolts are not really necessary, although they give the joins extra strength, should you feel this is necessary.

Once complete all the sections were unclipped, turned back the right way up, and re-clipped using the toggle catches.

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The original section of Dave's track was created on a slope, so where this section and my new sections were joining there is about an inch (25mm) height difference. My original plan was to create a couple of plywood slopes to join the 2 slots that cross these boards, but after some discussion it was decided that it would be better to raise the whole of the MDF board, which was to meet the original track, at one end, to match them up.

This meant a bit of unscrewing, glue-bond breaking and inserting wedges..... say it fast and it sounds easy! Anyway, it eventually got done, and a perfect match was achieved.

Next was the bit I was most nervous about; the routing. I have made a rally stage previously, in fact Mike Buss, Mike Dove and myself spent a weekend creating 3 tracks a few years ago, using the same build method. Last time Mike Buss did the routing, with our assistance. This time I said to Mike that I would like to attempt the routing myself, so that I could learn better how to do it. There were bound to be mistakes, but there were last time too, so you just have to go for it.... besides.... isn't filler a wonderful thing?
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Firstly, a SAFETY announcement: MDF produces dangerous dust and harmful vapour when cut. An FFP3 rated dust mask is the most advisable type to have if you are exposed to MDF dust, and one combined with an organic vapour filter will also provide protection against any formaldehyde vapours that are present.....you have been warned!

Freehand routing is very difficult, and if used you will usually end up having a lot of unevenness to the slot. We have found that you must create a solid/secure way of guiding the router. For straights, that is to use a straight piece of wood and screw in a few locations to secure it, then, when guiding the router down this wood, there should be no chance of it moving.

The first step though, is to do all of the curves. In our experience, it is much easier to join curves with a straight than the other way around when routing. The curves were done two ways:

a ) With the router, and the utilization of a modified straight cutting guide extension (the ones with the parallel rails) for curves of 85mm radius and above, and

b ) With a dremmel and a 'Circle Cutting Guide' for smaller radii.

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The modification to the 'straight cutting guide extension' was to screw a piece of wood to the underside of it, and then drill a hole as close to the router as possible. This would allow the tightest radius with this extension. A piece of brass tube was bonded in here, to strengthen this new hole, for when using it as the centre radius point.

A 3.2mm (1/8") two-flute router bit was used, which gives an ideal guide slot width. The MDF board was 9mm thick, so I set the guide depth to 8mm, which means that there will still be some material to hold everything together once routed. You could use 7mm if your guides will only go that deep. At our club a lot of deep guides are used, so I'm just trying to accommodate everyone.

Using the centre points I had previously marked, a small pilot hole was drilled. Then, a 3mm (1/8th") hole was drilled at the start of the first curve. With the modified straight cutting guide fitted into the router, a screw was now inserted into the brass tube and screwed into the centre point of the curve, not too tight, as you still need to move it to position the router. Then, put the router bit into the hole at the start of the curve. Now a very important bit, lock the cutting guide in position! I missed doing this three times! If you do, then don't worry, just reach for the filler!
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You will see those errors in a couple of the following photos:

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The next point is where it is nice if there are two of you, one to press the routers ON button and move it around to the curves end point, and the other to steady the location of the centre point screw and/or do some form of dust extraction. Not absolutely necessary, but helpful. Once you reach the end point then turn the router OFF. Another important bit here.... Do not move until the router bit stops spinning! Apologies if you think I'm explaining this as if you are daft, but I'm just highlighting some of the areas that we made mistakes ourselves. Hopefully you can avoid those mistakes.

For any radii smaller than the 85mm minimum this setup can achieve, we used a dremel with the cutting circle guide attached. As the dremel is not as powerful as the router, two cuts are necessary, the first one at 4mm and the other at 8mm. If you try and do it in one you will most likely burn your way through, and burn the router bit out too! As you can see, routing MDF is a dusty job.

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Once all the radii were done we then joined them all up with the straights. For the solid router guide, we used a couple of different lengths of wood, each with flat sides and a few holes drilled through for securing screws. The relevant length can be selected and then can be positioned by putting the router bit (still attached to the router) into the end point of each radii, so that it can be set exactly in the correct position. Once happy with the position, the wood can be temporarily screwed into position. This is where the different holes come in useful, select holes that are well away from any guide slot positions. Now the router can be run along the length of the straight from one end of a radii to the end of the other radii.

After any routing, we cleaned the dust out of the slot with a screwdriver blade, and vacuumed it up. These pictures show the finished routing, one from each direction:

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Once all the dust had been cleaned off the track we loaded it all back into my car and I relocated it up my attic, ready for painting, scenery, copper tape and the electrics to be done.

To be continued.........
 

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Speaking of your attic .. did you ever get to finish the roof and putting the track down there?

the mask suits you by the way ... ;))
 

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Hi Pete, yes, the attic is almost ready for a track. At the moment I'm using the space for this track build though. Roof is insulated and covered. Floor is insulated and covered too. All woodworm treated as well. I've also put a workbench at one end and moved all my slot car build crap out of the kitchen!
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As I now have 2 rally stages almost complete, I doubt I'll do a big track, unless we lose our club room.
 

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Great build and a nice description.

For the "tight" radius turns I just made up a couple of simple adapters to allow for the router to be used.

First piece was just a piece of angle that just need 4 holes drilled in it. Two of these holes have to match the spacing of the guide bars on the router. The second piece is just a flat piece of material, with a least one hole on the center line, and another pair of holes to match the holes on the angle.

It is then possible to have the centre of the circle you are routing as close as you like to the router bit,

Angle fitted to guide bars.

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Flat piece of material. Thin piece of alloy in this case.

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Position when used for larger curves.

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Positioned for very tight curves,

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Kevs Racing Bits
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One of the tips I picked up here and seems logical, route two curves and join afterwards with the straight.
 

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Discussion Starter · #15 ·
That is a great adapter Dave, and before doing another track I think I would create something similar. I definitely think that having the right 'tools' for the job speeds things up and takes some of the frustration out of the process. However, ours did work well, it was only 'user error' that caused the mistakes...... the 'user' being myself!
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At the time you never think you are going to build another track though do you? I found the process very interesting, and enjoyed working with the guys that helped me, but there is no denying, it is hard work, and very time consuming. Hopefully it will be worth it in the end though
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You can get so much track on a routed stage, especially for a rally stage where you can have tighter bends and more of them. One of the more frustrating aspects of plastic track is the power drops you can get around the circuit. If you are doing a competitive event there is nothing worse than some of the competitors having a perfect track and the other half suffering from a drastic power drop half way around. With this sort of track that is much less likely to happen.
 

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Too many tight turns there for me, I'd never get my NSR Mosler round it!!
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Lovely jog, can't wait to see the fully finished job.

I'll pop in next time i am over.
 

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"At the time you never think you are going to build another track though do you?"

After each track that I have built I am itching to build another incorporating fresh idea's or seeing where I could have made improvements.

Yes rally tracks are a great way to get a lot of track into a small space, the first track that I ever built had a 21 foot lap on a 4x4 foot base.

Don't forget that if you include a DPDT switch in your layout you can run the track in ether direction with just the flip of the switch. So there is twice as much fun straight away. It can be very surprising just how different a track can be driven in the opposite direction. A compound curve that tightens in one direction is a lot harder to get right then the same curve driven from the tightest part and then opens out.

I would also like to build another track that uses two slots just a 1/4 inch apart. So you can get away with just 3 strips of tape or braid at that point.

See the video below where I used this idea on the large corner.

 

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LOL, I was only guessing, at 100, and I did say diameter BTW. ..........

keep us up to speed,

Simon
 

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Kevs Racing Bits
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...Don't forget that if you include a DPDT switch in your layout you can run the track in ether direction with just the flip of the switch...
DPDT already fitted to a few Manx Slot Rally stages, no doubt already in the plans for Stoney Mountain Quarry too
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