Hope you enjoyed the last round of pics... If you did, Alan managed to put together a wee treat...
Well impressed with the way that turned out... Thanks Alan!
That was just a wee test run using a variable power supply set at around 3.5V. Good to finally see some of the fruits of your labour!
As you can see, we've painted the slots to differentiate lane colour... After trying some of my 4y/o nephew's squeezy-bottle poster paints on a test piece, we decided that it wasn't going to give us the coverage we needed, so we tried some car spray paints on another offcut. Although it was quite easy to spray too much in one area and get pools and puddles, it was easy enough to wipe up with some kitchen roll or toilet paper if you didn't leave it sitting for too long.
The yellow does look a little pale against the natural MDF, but once the tape is down and the track surface is painted, I reckon it'll be a good contrast. Talking about the surface, I had intended to use a 5l tin of white Sandtex with a couple of 150ml tins of black to grey it down a bit, but I still wasn't happy it would be quite dark enough... My local B&Q (hardware store for all you non-Brits) doesn't stock the fine textured black, so it was the best I could come up with. Until...
Wandering around B&Q again (as one does), I discovered an almost perfect colour... Fine Textured Silver Blue. Looking at the title, you wouldn't think it would be particularly suitable, but if you were to see it, you'd understand. I'll post a pic or two once I get it painted. I quickly collared one of the store assistants and asked if I could swap my white for the blue, even though I didn't have my receipt...
"As long as it was unopened, resellable and scans into the stores inventory system, no problem."
Next day, I turned up with the offending tin and true to their word, out comes a credit note 2 mins later! Well chuffed... That saved me forking out another £15-£18 that I could ill-afford at the end of the month and having to explain it to the missus! Cheers , B&Q!
As you may have noticed from the first couple of pictures, we've managed to get a little further on...
We had already cut out the basic shape of the "esses", and matched up the join on the back straight. I screwed that down to the riser and started playing around with bits of spare decking planks to form the gradient supports. The picture above shows the last 6ft or so of the back straight and as you can see, 3/4in MDF really does flex a substantial amount... Takes quite a bit of force though; thank God for mechanical leverage! :oD
Next (and last sheet) to be done was the 8'x4' which would hold the rest of the start/finish straight and the first corner. Turn 1 is a compound corner which tightens up as you pass the 90* mark. After cutting out a section so that the leading edge of the climb would sit flush nd routing Turn 1, we slid the sheet under. Then it was simply a case of joining the dots to complete the straight. As everything seemed to line up, we secured that sheet too.
Crude but effective decking planks form a very solid support, and the above photo illustrates the slightly shallower grade up to the back straight.
Next up, we'll be filling any screw heads sitting slightly below flush with the track surface. We'll also be sinking some brass screws down through the track, for power feeds from underneath the track to the copper tape.
After what seemed like aeons of marking out and routing (which took MUCH less time that the marking) we finally started "getting 3-D" on Sunday morning.
First up, we assembled the rear riser that's going to support the back straight. Despite a bit of cack-handed bandsaw use by me the finished article is remarkably straight and level. We screwed it down securely and performed a quick " have we over-engineered it?" test. Luckily Doug's relatively skinny so the answer would seem to be "Yes!". Thankfully. We didn't cut access holes into the support as the power is going to be fed into the track both just before and just after the staraight as well as on the start/finish straight so there shouldn't be anything inside the box at all.
Its worth pointing out that the first picture shows the entire table clearer that its been since Doug started this - we truly are masters of shifting junk back and forth. Sadly much of it seems to have found its way into my garage across the road. Hmmm...
Buoyed on by our success (and a mug of tea) we decided that now was the time to begin the cutting of the first board. Ulp.
We'd been debating the exact profile to cut around the track for a while. Doug has favoured "wiggly", with the edges of the board being cut to the profile of how the track will flow with the cut tracks being similar to the racing line. I, however, am far lazier and just wanted to cut straight - parallel to the routed tracks. We could then paint on the road and disguise the straightness of the cuts with some cunning landscaping. Eventually we decided to compromise and cut an initial curve near the apex and then straighten - the edges to be "roughed-up" later with the cunning landscaping.
I got a bit arty with the camera at this point, so whilst the photo's lovely it doesn't really show much more than what a nice model of a Supra we've been using as out guinea-pig car. Why? Because its both long and wide and so will give us an idea of the maximum space cars should take up as they round corners.
This whole cutting thing seemed much easier than we'd (well, I'd) feared so it didn't take long for us to trim out the rest of the board and get an idea of the levels. The straight at the back is 9 inches above the datum table level, but as the cars have about 10 feet of track to reach this level then traction shouldn't be a problem. In the 4th picture its worth noting that the lowest edge of the board will be trimmed back to meet up with the one remaining board to be cut - the start/finish straight that will then turn 180* under the flyover to join the bottom of this slope.
Later in the day we also made a start on cutting the second main board with the downhill hairpins to the start/finish line, but I'd put the camera to bed by then.
Well... It's been over a year since I finished the table, and I finally decided that I really should make a start on the actual track.
I had thought of using a flexible "fence" (read: plastic pipe) and screwing it down at 2" intervals, however, the test cuts weren't very satisfactory, so I relented and simplified the layout somewhat, so I could use a radius arm instead. If I'd stuck to the original plan, I'd have needed to construct centre points for the radius arm somewhere through walls etc. so discretion (or rather practicality) was the better part of valour...
With the help of a friend, the routing seems to be going remarkably smoothly and so far, no major hiccups. We've routed the first sheet of 5'x10' MDF already and nearly finished the second.
The next stage will be to build the risers for the back straight and cut out a rough outline of the track edges. If I get some time I'll post some photos and let you see what's happening...
The picture shows a plan I made up on Slotcar Manager (SlotMan). It shows the full size of the garage, (just over 16'x8') and the shape of the table (5' and 3' deep approx) and how the track will fit on. The small grid squares represent 25mm, so if you're really desperate for exact dimensions then you can count them!
Lane centres are 100mm with the overall width of the track being 300mm at all times. I'll probably move the edges of the track in and out from the slots going round corners etc to make it look like the cars are taking the racing line, whilst also giving enough sliding room at the same time.
A lap of the track is intended to go something like this:
Starting from the triangle (start/finish line) you sprint along the first straight, under the bridge and into the Parabolica. It starts off at 1.6/1.7m radius and tightens up progressively into a 0.2/0.3m radius. It then opens out and you're flat out down the front straight to the hairpin. This is a o.1/0.2m radius and will be the slowest corner. From there you climb up The Sweeps, over the bridge and into another tightening left-hander (0.1/0.2m) where the track flattens out. This takes you out onto the level 4.3m (14' ish) back straight and into the twisty section. From the end of the straight and out of the last 0.1/0.2m radius, you start to drop down through The Esses and into Karussell. This will be a 0.2/0.3m switchback which pops you out straight into "The Corkscrew", the inspiration for which can be found on OldSlotRacer.com. I reckon a lot of cars will come off here, but the idea is that you'll just have to take the elevation changes into account too, as it's designed to be technical as well as smoothe and flowing, as far as I can make it...
The idea behind the design and choice of radii is to give both lanes the same running distance, but also roughly the same amount of tight corners or wide bends.
Well that's it until next time... Perhaps I'll have built a shed in the garden by then and I'll be able to unearth the table to take some pictures of it.
