I delayed the track improvement project while the Racing to the Future™ program ran through its Fall and Spring schedule. That kept me busy through the end of March 2013. Now that we have celebrated 3 new Racing to the Future™ Champions, it’s time to get back into gear and get Woodrum Ridge Raceway back on track…literally. So just to prove I have no focus whatsoever, as I was planning the other side of the track’s banking structure, I took notice of the condition of the jumper tracks that deliver the power to the oval. Seeing the rails beginning to degrade gave me another sub-project to work on. After all, there’s no point in getting the banking all complete and then rip up the track again to fix some wiring. So in this installment we will not only show the final steps in completing the banking process, we will look at a new (to me) process of wiring the jumper segments around the layout of the track to prevent corrosion.
The corrosion pictured above completely caught my attention and needed to be addressed before any new work was started on the banking alterations. The original jumper lines were soldered directly to the rails. The flux used, although cleaned after the soldering process, left enough residue to cause this kind of damage over 6 years of racing.
This was the bottom of one of the original jumper sections. The top wire had worked its way loose. That along with the corrosion issue demanded action. There had to be a better way of building these jumper sections. I started researching options and decided to follow some of the building guides that cover routed 1/32nd scale tracks. Those articles described how to drop the copper or braid through the track surface and attach the wiring to those extensions. How do we accomplish the same idea with solid rails? And how do we avoid soldering directly to the rail, eventually having the corrosion reappear a few years down the road?
I decided the best way to resolve this problem was to create a mechanical connection to the rail, with no solder at the rails at all. I reshaped some track rail harvested from a scrap piece of track, cut and bent it to shape, and soldered a lead wire to the this new piece. We’ll call these “jumper tabs”. Then I took the jumper tab and scrubbed it clean, removing all traces of flux, so we reduce the chance these would ever corrode. We’ll get into the details below.
You can harvest a piece of rail from some scrap track. I’m using Tomy AFX track, keeping with the same type used in the layout. Just pull up a section. The rails are crimped under the track surface and will easily snap at the crimped section with a little wiggling back and forth. A 2-3 inch section will give you enough material to make several jumper tabs.
After getting that first segment of rail, we will bend an edge about 1/8th on an inch long, to form an “L” shape. Don’t worry if you make it a bit longer, we will file and shape it as we go through the process.
Here’s what your “L” shape piece should look like. While we still have the whole piece, we will file the short end of the “L”, sharpening the edge like a blade. This will make inserting it into the track easier, later in the process.
Cut the newly bent and sharpened tab about 1/4 – 3/8ths of an inch from the bend. This will give you room to solder the jumper wire and still allow it to fit within the area under track without affecting how the track lays down on the table surface.
Here are some tabs, made up and ready for the next step.
After tinning your wire and the surface of the tab, solder the two together as shown. Once cool, I scrub the assembly with Dawn soap and a toothbrush to remove any flux left behind. The scrubbing process also tests your solder connection and let’s you know it’s good and secure.
We can start prepping the rail on the bottom of our jumper tracks now. The Tomy AFX track (as well as the other brands) has areas of the rails exposed. We will use the sharpened edge of our “L” shaped jumper tabs to insert the tabs between the exposed rail and the plastic track. You may need to remove a small piece of the plastic to widen the exposed area of rail. A sharp X-Acto knife will do that easily. Make just enough room for the jumper tab. Removing too much may allow the inserted tab to move or shift.
This picture shows the jumper tabs pushed into place against the track rails. Don’t worry if some portion of the jumper tab sticks up above the rail on the racing surface. Will take care of that in the next steps. I used a small screwdriver to push the jumper tabs into the track, making sure they were tight against the rail surface. Once you have a pair place, test the connection to make sure the track rails have power. You can miss touching the rail or have some plastic between the rail and the jumper tab and not make the electrical connections. If this happens, simply remove the jumper tab and reinstall it, making sure the tab stays in contact with the track rail as you reposition it.
Once you have all four of the rails connected, it should look something like this. The tabs may still be able to work their way loose. So after you test the electrical connection and you know you have power through your new jumper tabs, the next step makes sure they will not move or disconnect over time.
Using a hot glue gun, coat the jumper tabs and a 1/2 inch or so of the lead wire of the jumpers. Use small amounts of hot glue at a time and allow it to cool before the next application of hot glue. You don’t want to spend all this time setting up the jumper tabs only to melt or distort your track with the hot glue. Take your time on this step.
Once the glue has cooled, your jumper tabs should look something like this. Now it takes some serious effort to pull a jumper line loose from the track.
Now we can smooth out the surface of the rails on the top side of the racing surface. In the circle above you can see where the jumper tab is contacting the track rail. It is also sticking up above the track rail surface a bit. Using a small, flat jeweller’s file, grind away the excess tab and make it level with the top of the track rail. Avoid using a Dremel or similar power tool. It would be easy to damage the plastic track surface or grind too much of the track rail away.
This is what the jumper tab should look like once you have it filed down into the correct position. It’s below the track surface and just slightly below the top of the track rail’s top edge.
Repeat the process for each of your jumper sections you want to add. This helps distribute the power evenly across the length of your track. The circles in the picture above show each of the jumper locations on Woodrum Ridge Raceway’s two tracks.
Now that we have addressed the power issue, let’s get back to finishing those banked turns!
When we last left the banked turns, the screw holes were filled, sanded and leveled with the track surface. In the pictures above you can see where we painted the patched areas with flat black paint. The track itself will get painted dark gray. The black patching shown here will help keep the gray paint even in appearance and will require fewer coats to make it even in tone. This also helps find any rough spots that may need to be retouched or sanded smoother before we move to the next steps of this project.
To give you a better idea of how much difference there is in the new banking versus the stock AFX banking, the new turns are only 1-3/4 of an inch high. Stock banking sits almost 4-1/2 inches high.
One challenge to expect with this banking process, is the turn will have a gap in at least one spot. The track separates slightly during the forming process when the dish-shape starts coming together. I made an effort to get the gap in one spot so it was the only one I would have to fix. On the right of the photo above you can see the gap that was left from the banking process. It was only 3/32nds of an inch wide. I filled the gap with some rectangular ABS plastic from Evergreen and CA glued (super glue – thicker type) it into place. Once cured, I sanded and shaped it to the track surface. The finished gap is on the lower left of the picture. The gap repair extends all the way down the depth of the slot so there is no interference with the guide pin passing though it. Repeat this process across the width of the track, filling all of the gaps left by the banking process. Also, the track rail on the upper right has an extra piece of rail extending the connection between the two pieces of track. There was electrical contact prior to the rail addition, but I added it as a precaution. As the track gets older and settles, that connection may have separated without the extra piece of rail.
Fixing Bowed Track
The oval at Woodrum Ridge Raceway is a combination of original (1986) Tomy AFX Track, newer (prior to the mold re-tooling in 2013) Tomy AFX track and Auto World Track. The vast majority of the track I purchased was straight and had no twists, warps or bowing. However, a couple of pieces of the newer AFX and Auto World 15 inch straights had a minor bow to them. This usually happens during the de-molding process during production at the factory. Knowing others have had this issue too, I decided to add a fix for this issue, instead of searching through additional purchases to find the “perfect” pieces. I only had 4 pieces of bowed track total, so that was not too bad considering how many of pieces go into the make up of this layout.
Here’s one of the two bowed pairs of 15 inch track I had. You can see where the sides of the track are separated near the center (at the green arrow). This leaves a gap about 3/32nd wide.
I took a bar clamp and gently squeezed the track sections together. Once the gap disappeared I stopped squeezing the sections and let the clamp hold them together.
Next, I drilled some pilot holes with a 1/16th inch drill bit. This track will be nailed down, but you could use the same method used with the banked turns, using screws and patching the countersink holes.
Once we have the nails tapped in, we will countersink them and file them flush with the track surface. Here we can see a small part of the head is above the track surface.
Very gently tap the nail with a nail set punch and a small tack hammer. Do not strike hard as this could cause the track to break. You are only trying to place the head a bit closer into the track surface. Filing will take care of the rest.
After setting the nail as far as you can safely do, take a flat file and grind the head flush with the track surface. The bottom picture shows the finished nail.
And now I will fess up and let you all in on a major mistake I made while building the new oval. Being all gung-ho to get this project started last year, I made the error of not accounting for the difference in length the inside track would have versus the outside track, due to the bending process of forming the banking. I wound up having the outside two lanes 1/4 of an inch shorter than the inside lanes. Oops. Not a major issue though. The inside lanes lined up perfectly with a 9 inch straight completing the oval. That meant I needed to create a 8-3/4 inch straight for the outside lanes. I took a 15 inch straight, since I had more of those, removed a section from the center to get the correct length and then re-assembled the section of track. Below are a couple of pictures of the finished piece. It’s completely smooth and sits between the two jumper segments of the back straight, so there is no power issues. Both sides of the new section power up as any normal piece of track would. So the lesson learned, measure twice (including banked turns) and avoid cutting at all.
Here’s the newly pieced together 8-3/4 inch straight.
A close-up of the joined section. Plastic strips glued below the track keep it all together.
So now that everything is assembled, we have one more step to make sure we have the best driving experience on these new banked turns. A side effect of forming the dished banking from flat turns is a slight distortion of the slot itself. This is very minor, but can cause bladed guides to hang or drag more than normal. This is easily fixed by taking a flat jeweler’s file and dragging it through the slots, completely through the turns and transition straights. You will see a curl of plastic come out of the slots and this resolves the pinched effect.
The jeweler’s file that I use to clean up the slots. It is a flat metal file, 1/16th inch thick and 1/4 inch wide.
Just drag the file along the slot to de-burr and widen the pinched areas of the new banking.
This brings us to the end of the July 4th weekend. As you can see in the photo above, the construction crew has left some debris to clean up. The next steps will be skid aprons and retaining walls. We will be using a new material for the retaining walls. It’s cheap, easy to find and conforms to the turns with no effort. I wish I thought about using this a long time ago.
More details in the next article.