Mark’s Slot Racing Page
My meager attempt at a how-to-build a routed track guide
04/24/2007
Hi. Last Christmas I bought my 4 yr old son, Michael, a Scalextric racing set for Christmas (based on his love of his Tyco battery powered set and my fond childhood memories of days spent racing Aurora HO race cars in the 60’s). He’s had a ball with it but it’s a bit of a pain to walk around on the family room floor and to move and setup. One day I looked up 1/32 racing on Google and happened across a newsgroup/forum that talked about routed race tracks. I started Googling “routed slot racing” and I came across a link in SlotForums.com from a fellow in Sweden called Claes and his thread entitled ‘My First ‘REAL” Routed Track.’ It was basically a primer on designing, routing, and modeling a routed track. After reading all 5 pages of his thread and watching his awesome track take shape, I had a serious case of the “I’ve got to build one of these myself” bug. So I posted a couple tentative questions and was answered promptly and politely by several of the denizens of SF. I’ve got to say these guys are incredible. They are willing to share their (considerable) knowledge of track building, slot racing, and modeling with anyone and everyone. They are undoubtedly the nicest on-line group of people I’ve ever had the pleasure to come across.
Anyway, I researched everything I could find about routed tracks and the more I read the stronger the bug bit me. If I was hooked before, now I was more determined than ever to build my own routed track. My biggest problem was space – there simply wasn’t enough space in my house to store a big track when it’s not in use (taking out the pool table is NOT an option!). So I walked around my basement thinking where, where, where… and then the light bulb lit over my head! I got out my tape measure and measured the space available -- on my workshop ceiling!!
Next I had to figure out how to maximize a 3 ½ x 8 foot layout. I wanted a 3 lane track so my daughter or wife (or guests) could race too. It needed to have a long straight, maybe banked curves (my son likes going flat out –well, who doesn’t?) and some curves to make it more interesting. To maximize the space and add to the visual appeal, I decided to elevate the back straight which would also let me maximize the length of curves in the lower section (they’ll fit under the raised part of the track). So back to Google and SF for 1/32 scale layout ideas. Though many of the designs were great, I decided to choose an “M” style track that I’d doodled on some scale graph paper. The sharpest curves are near the front within easy reach to make marshalling easier, the driver stations can be near each other at the front, I can get almost 30 linear feet of track in my limited space and best of all it kind of looks like the “M” in Mark and Michael.
Here’s my initial 3 lane draft:
After seeing several examples of it, I decided I really like the idea of freeform routing the grooves (the cars follow the race lines –cutting corners, basically shortening the track) but I also am building this primarily for my 4 yr old (yeah right) so I decided -- at least at this point -- not to tighten up the lanes at the top of the track (which should help with de-railings too) and only merge the lines at the sharp turns where it transitions to the tight hairpin turns in front.
Here’s a picture that shows a more polished geometrical radius track. I’ll use this drawing to delineate the roadway when the time comes – the cars won’t run the currently marked lines (at least unless someone at SF talks me out of it) but I'll have a template of the roadway. I plan to make it from 4 pieces of MDF so I can use the first ones as templates for the second ones.
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It was recommended to me at SF that I get some model railroading books on eBay to learn about bench work and I did just that. I also found some excellent pages at SlotForum as well as sites I Googled showing how it was done.
Saturday, I went to Lowe's and bought a sheet of 3/8" plywood and had it cut into 4" x 8' strips for the benchwork. I also bought some 8' poplar 1x2's and some pine 1x2's to use as bracing. I'm planning to build as lightweight yet strong a bench as possible. Tomorrow I'm buying a pair of folding table legs from Harbor Freight to stand the table on when in use. I plan to take it outside to use as my work surface when I route the track (I ordered my solid carbide 5/32" router bit yesterday). The benchwork and pictures of that process are coming next.
The Bench
04/28/2007
Because I assembled so many Brunswick Pool tables in my illustrious past, I have a strong respect for just how strong a plywood frame can be. I'm not going to be putting anywhere near 600 pounds of slate on this bench so I figure to engineer a nice light but strong frame from 3/8 inch plywood for the track's base.
The first thing I did was cut a couple dozen 4 inch blocks of poplar to act as glue blocks for screwing the frame together.
Then I cut 3/4" off of 2 of the 4" x 8' plywood strips (so they would fit inside the frame).
I cut the end pieces of the outside frame from one of the 8' plywood strips 43" long (figuring I'd need the extra inch for the layout later). I pre-drilled them to make it easier to assemble.
I put together the outside frame and then added the long crossmembers.
After dragging the assembled frame back to my crowded work area I started measuring for the cross pieces. I measured each space individually so as to keep the frame relatively rectangular. I'm not real concerned about it though -- I'm planning to use a flush trim router bit with a bearing to cut off the MDF when it's permanently mounted. Below is part of the stack of cross braces.
Below is the frame with some of the cross pieces installed. At this point it is incredibly light (well under 20 pounds I'd say) and very solid.
I've added several more cross pieces since this photo but my cordless battery bellied-up so I couldn't finish as planned and I've called it a night. I have about 4-5 hours of time invested in the benchwork so far. Next time I'll finish the crosspieces. They will be placed on 16" centers except at the top where the elevated straight will be. I will place them on 8" centers there so I can better support the track (no sagging allowed) :O)
Below is a picture of where I've left off for the evening.
Today I spent a couple more hours making cross pieces and putting them in place. In a perfect world I'd have had time to mount the folding legs too.... Next time for sure.
Below is the "final" frame of the bench. Even with all the cross pieces I'd guess it's still around 30-35 pounds or so. Not too bad methinks.
05/05/2007
Legs:
I spent a couple hours gluing and screwing 2 strips of plywood last night and some reinforcing blocks <sigh>. You know, I’m 50 yrs old and well aware (even preach it to my kids) that you get what you pay for. But gee, $20 for a pair of lightweight folding legs (even with bad reviews) was just too good a deal to pass up <shaking head>.
The problem with the design of the legs is that the top of the “L’ on the legs is too short. When you try to fold the legs they try to cam out of the mounting screws. Since I don’t want the bench any higher than necessary, adding some spacer blocks under the mounting flange (the easy fix) was not an option. So I used my ¾ brad point drill bit and drilled a row of holes to make some relief for the top edge of the leg, and I took a pair of channel locks and bent those suckers so that the "cam’s" profile was even lower.
Another couple short pieces of plywood to bridge the frame (reinforced with glue blocks) and the braces are mounted too.
The frame is very strong and light but a little more “flexible” than I thought it would be. I’m sure better legs and bracing would stiffen it up but for now I’m hoping that adding the roadway to the top of it will provide the stiffness. Time will tell. At least for now, I’m claiming to have a free standing bench to build (and work) on.
The Finished bench
I’m thinking now that I might want to simplify the layout…. maybe still keep the elevated long back straight but instead of the repeated sweeping turns just have one that curves up toward the straight from the bottom left then back to the other on the bottom right. Sort of like an “anthill” under the straight.
Future drawing here :O)
This would give me more realistic opportunities to do cliffs dropping from the elevated roadbed, allow a less elevated long straight (for head clearance below it when stored), and saves me a piece of MDF (but still allows me to reuse the elevated section if I want to create the twisties once Michael has mastered driving the slot). Oh and did I mention it'd be a lot easier too? :O) I asked the experts at SlotForum for their opinions and after weighing them I'll decide which way the layout will go.
Anyway, it looks like I'm ready for some MDF, some layout work, and a bunch of routing. Stay tuned!
05/07/2007
Design
OK. I've decided that I am not going to make a simplified track design. BUT. I am going to build it out of just 1 sheet (instead of the 2 sheets I already planned). So, I'm going to poll the folks at SF to see what they think of the 2 designs I've narrowed it to and go from there. Below are the choices for the track (now titled Mountain State Motorway). Feel free to vote at SlotForum.com!
05/13/2007
MDF
I started the morning Saturday by going to Lowes to buy a sheet of MDF. Wouldn't you know that Lowes doesn't sell 1/2" MDF. So I used my fingers instead of my gas and found out that Home Depot stocks it. Sixteen bucks and a second trip out later I'm ready to begin cutting the elevated straight piece from the sheet. Better yet, MDF is an inch oversize so I have a LITTLE bit of extra space for the lower center section.
My son decided to water the MDF while it sat in my carport waiting to become 2 pieces -- fortunately he used a watering can instead of the hose -- and it created an interesting rippley corrugated effect near the bottom edge of the sheet that might make a dandy washboard surface effect. I decided to make that the underside of the track. The worst of it is along the bottom edge that's getting cut off anyway. No real harm, methinks.
The bench got it's acid test as I used it as a cutting platform and to my joy it supports that heavy ass sheet of sawdust remarkably well. I opted to use a Skil Saw set to just barely cut through the MDF rather than try to brace and support the sheet hanging off the bench and just used the Jigsaw to cut the inside corners from the straight. The sheet is now officially the "upper straight" and the "infield."
Oh I also collected a quart of sawdust to paint and use as grass when I get to the modeling phase.
I guess it's time to finalize the design.... since nobody at SlotForum really cares (excepting Bill maybe) what layout I choose, I've decided on design #2 as it will maximize the track length and possibly be slightly easier to learn to drive in the short run. After being reminded how freaking heavy MDF is I almost wish there had been an outcry of "use design 1" from the gallery. ;O)
We carried the bench and the now 2 pieces of MDF back to the basement (out of the weather) to await layout work. One day later this week I will add some attachment blocking to the bench and attach the "infield" on the center bottom of it. Expect some pictures of the layout work to follow. Thanks for following along.
05/17/2007
Layout
Friday night I added some blocking to mount the center section of the MDF to the bench in preparation for the layout work. Since I've been noodling the layout the whole time on graph paper, I have pretty accurate dimensions and locations for pivot points. I transferred those to the MDF and drilled the pilot holes for my homemade compass (a piece of scrap poplar 1x2 with a few graduation marks). Very high tech!
Since I was extremely careful, I only drilled about 3 of the pivot holes in the wrong place. Nice thing about this MDF stuff -- it will be very easy to hide my mistakes on. As my friend the contractor says, "caulk and paint, caulk and paint, makes a carpenter what he ain't!" :O)
Since the MDF is oversized an inch, I have an extra 1/2 inch between the middle sections of the ess turns that I hadn't initially counted on during the design phase. I plan to use that space for barriers when I get to the modeling phase (maybe steal a little Dremel-ed stone wall idea for there!).
I don't plan to skeleton-ize the center track section until I have the slots layed out and routed. Next steps planned include joining the upper and lower parts of the track together and laying out the center lane all the way around. I don't think I'm going to merge the lanes much. I want to keep it easier to drive for my little carpenter/slot car driver in training.
05/18/2007
I joined the upper and lower sections and trimmed off some of the excess MDF from the bottommost lower outside corners. I also have layed out the curves for the upper straight turns and layed out the center slot going all the way around the track.
I think I'm going to change the corner radii so that they're not so sharp (currently a 10"D circle), but otherwise I'm pretty happy with the layout.
After tweaking the curves in the center slot I'll be ready to route the slots.
05/29/2007
Routing
Saturday I moved the two pieces of MDF, the bench, and my tools outside to the backyard. I built a couple of router bases out of acrylic plexiglass ($4.88US) to use as a pivot arm and base for my theoretical “secondary” routing (I thought I’d route the center lane and then use that slot as a guide for routing the other 2 lanes). I used hotglue to glue the plastic to the bottom of my router base. I had a solid carbide 5/32 router bit that I bought on-line for cutting the slot and I used it to cut approximately a ¼ - 5/16ths inch deep slot in the curves in 2 passes. After I had the curves routed, I took a putty knife and “cut” the pivot arm off the router base, then I reset my depth back to the midpoint depth setting, set the bit into the slot at the end of one curve and took a straightedge and set it flush to the router base (which conveniently has a 3 inch radius from the bit) screwing the straightedge to the track. Then I went to the other end of the curve I was connecting and set the bit in the slot and did the same thing. I double checked my original spacing and found that the straightedge had pivoted away from the flush edge point that I first set. A couple of back-and-forths later and the lane distance was set right. The first couple times I got lucky and started at the end that my routing direction had the base turning into the straightedge but eventually the law of averages caught up with me and I walked the base away from the straightedge a couple of inches at the start of a cut, making a nice curly cut instead of a straight one. Eventually though and with only a few minor errors I finished routing the center lane.
Now it was time for my lane spacer base. I glued the other 8 x 8 inch piece of plastic to my router base and scribed a line 3 inches parallel to the bit. I drilled 2 holes on that line for the pins that would run in the slot and guide the router around the track with perfect 3 inch lane spacing. I thought (erroneously as you will soon see) that it would be better to space the pins as far apart as possible. At the first curve I came to I saw the cutting progress of the slot moving closer than the desired 3 inch space. $hit! Well I wasn’t going to experiment with pin spacing to try to find the ideal distance so I removed that base, glued the pivot arm base back on and commenced to routing all the radii and all the straights the hard way. It took me the best part of 7 hours all total to do all the routing. I have a bad back (disk problems) and the tired-er I got the more frequent I made mistakes too. Below is the picture with all 3 lanes routed:
After finishing all the routing, I screwed a poplar 1 x 2 to the top of the side straights to support it while I cut ¼ inch slots (to help bend the elevations into the upper section) into the bottom of the track perpendicular to the slots on the opposite side. I did manage to do that without accidentally sawing the track in half. I’m taking my victories as they come now – however insignificant! J
I purchased a can of bondo and am planning to fill my mistakes in and start re-routing them next weekend. Mostly, at this point, I’m hoping I haven’t wasted a day and a sheet of MDF.
These are a few of the things that hindsight has taught me:
With a little luck all the work last Saturday may be salvageable….
Thanks for following along.
to be continued...
