172 replies to this topic

[Bigdogbro1]

Hello, everyone,

 

Thanks, Gregory, for the new member add!

 

OK, I have wanted to build a wood track for many years. I have two young grandsons that would love this hobby and the disciplines involved within it.

 

Now that I'm retired and have the means and have an idea for a four-lane 1/32 sized track in my walkout basement I need some help with some of the geometry for the turns and how I would need to fabricate (route) it. I have been watching and reading Steve Ogilvie's content and have picked up some great information.  I would like this track to be like a commercial track like Steve Ogilvie builds and have been designing around those ideas. I think I had better stick with a flat track but would like a few bank turns if I can get a good understanding of all the required geometry.

 

I currently have designed a 74-foot outer lane track that originally had all 3.5" lane spacing wall to wall. But after researching further, I feel the a 3.5" outer turn apron may be too narrow and think I can do a 4.5" outer apron. If you look at my track layout you can see the wider outer 4.5" turn gutter aprons but I cannot figure out how to route this track with the wider 4.5" outer gutter apron blending into the 3.5" inner apron on a opposite turn.  

 

I have seen track builds with lane spacing all the same where a router pin template is used and the builder started with getting a finished outer track edge formed then began routing the outer slot then moved inward to the next slot. I don't think that method will work for my track layout.

 

I sure could use some clarification and guidance to get me understanding the concept. Any support out there to get me on my way.

 

Thanks!

 

 

 

[Bill Seitz]

Rob,

 

The British Slot Car Racing Association has a great web page with one of the best articles I've seen for building a wood track - even explains how to design banked turns. https://slotcarracin...uild/track1.htm

 

I think the Chris Frost article above will answer a lot of questions.

 

A track can be routed using radius arms. Commercial ones are available, but something large enough for a slot car track are pricey. I've seen woodworkers making their own out of wood sheet stock. The problem that may arise is that the routing needs to be done flat, and the slots can constrict when bent to form banked turns. This maybe why all the banked tracks are built using a guide off the outside edge and working inward. That method works when all the wood has been cut and assembled in a track with banked turns - slots cut after banking. The Chris Frost article linked above discusses this.

 

I did notice the radii of your corners are small enough that you may be able to use the large Jasper circle cutting jig which does 53" diameter. However, while that would cut your slots, not the outer perimeter. Minecraft is the only commercial circle jig that I've seen able to expand to diameters beyond 53". The circle cutting guides are aimed at making small, round table tops, not slot car tracks.

 

I think you'll need at least 4 to 4.5" outside gutters. The inside ones will probably be fine at 3 to 3.5".

[breese]

Great CAD!!

 

Have you considered the outside lines might travel farther than the inside lanes?

[Bigdogbro1]

Hi Bob,

 

I sure have considered it. The design with all four slots of 3.5" lane spacing has a 66" difference inner to outer lane length. No crossovers or bridges on this one. Four heat races as normal.

 

Thanks for asking. Concerned with the routing technique with the outer lane gutter width change up. May be simple but It hasn't hit me yet.

[Paul Menkens]

Good luck! This video will give you an idea how a radius arm works.
 
 https://www.homedepo...1768841#overlay
 
Several years ago I routed three different tracks using a radius arm I improvised using a block of wood and some redi bolts. I did a scale  drawing of the layout and used a compass for the curves then connected them with a straight edge, then I built the table the same way you would build a model train table.
 
When the table was built I marked my center spots for my curves and drilled a hole for each one in the same place as I had used the pin on the compass on my drawings, I used a small nail the same size as the hole to pivot my improvised radius arm which I set to the size of the outside lane. I routed all my outside curves first then set it to the next lane in, my first track I spaced them at 4", the last one, at 4-1/2". I did this for the third and fourth lanes, the advantage of  doing all the outside lanes at once and then moving in to the next one, is that you're resetting your radius arm only once for each and you can be sure all are exactly the same where is if you reset it there will be slight differences.
 
When I had all the curves routed I used a straight board (1"x6") as a straight edge to route the connecting straightaways. I went a little beyond the end of the curves when I routed them and after the straights were done I filled in the extra curves with Bondo.
 
I used copper tape on these tracks rather then braid but if I were to resurrect the last one I would convert it to braid. Neither of these tracks were banked as they were made from particle board and it wouldn't bend like MDF but you can tilt the curves up.
 
I would suggest building something smaller then your blueprint to start, maybe a 4' x 8' tri-oval to get the hang of it.
 
Good luck!

[MSwiss]

With the size track you are building, and especially the the tightness of the turns, I don't think you want to route subsequent lanes using previous ones as a guide.

 

As the radius gets tighter, the router, guided by 2 pins, starts to get confused.

 

Below is what happened on the 2nd track I built, my 8 lane, 117' commercial flat track, with 4 3/8" inch lane spacing.

 

In my case, the cars still run normal, despite the little jogs.

 

I would stick with compass routing.

 

I can show you a good way to make a  precise compass arm.

 

I used the one I built on the first track I built, a 155' 8 lane King track.

 

I thought it worked superb.

 

What you haven't stated is your woodworking experience and equipment you have, or intend to buy.

 

As far as aprons, there is no rule that the inside apron has to be narrower.

 

If you need every fraction of an inch, to get around the track and run narrower inside aprons, you just connect them to the wider apron with a straight line and trim accordingly. 

 

IOW, you will cut the apron on the straightaway connecting the 2 turns, at an angle.

 

[Courtney S]

Im gonna make your life really easy especially with 1/32 cars look at racetrack scenics theyve got a new system where they build a routed layered wood track super easy to build you can use braid. You can use copper tape paints and assembles very easily. I dont have access to my computer at the moment. Be sure to check out their YouTube page as they just assembled their first production layout and its really neat.
https://www.facebook...mibextid=LQQJ4d
https://www.racetrackscenics.com/#/

[Bigdogbro1]

Thanks for the suggestions. 

 

Question: Is a 3.5" outer turn gutter enough width for 1/32 cars (5" to 6" long) or is 4.5" the way to go. 

 

I would rather not have the tail end of the cars scubbing the outer turn fence. 

 

I thought about the straight line router fence board to connect the turn lane slots to get the outer lane slot started.  The use of a router jig to cut the remaining slots.  I was going to test cut my small radius turns on some scrap with different jig pin spacing to eliminate that jog and good entry/exit geometry.

[breese]

I found this a very interesting video of a home built track.

https://youtu.be/IdS...ZTLJQwT9-GsSED7

[jimht]

I've referenced Luf at oldslotracer.com for years but apparently the site is no longer active.

 

Regardless, there were hundreds of pictures of tracks around the world routed using his methods.  If anyone knows if they are still available somewhere, please post a link.

 

Info is now available here: https://www.ggaub.com/slots/wood.shtml 

 

and here: https://www.slotcarr...build/part2.htm

[breese]

http://slotblog.net/...-steve-ogilvie/

[rvec]

This technique could be used to equalize lane lenght

Attached Images

• 

[Sloter]

Im gonna make your life really easy especially with 1/32 cars look at racetrack scenics theyve got a new system where they build a routed layered wood track super easy to build you can use braid. You can use copper tape paints and assembles very easily. I dont have access to my computer at the moment. Be sure to check out their YouTube page as they just assembled their first production layout and its really neat.
https://www.facebook...mibextid=LQQJ4d
https://www.racetrackscenics.com/#/

 

I would highly recommend Race Track Scenics as per above links, to build you a track. He has track kits available and custom kits. I am having a custom 4 lane built. Great pricing and is laser cut so you can have decreasing or increasing radius turns and much more. No wasted wood and time because of a miss cut. Many have stated that have built their own tracks, that if they where to do it again, they would gladly pay someone. Kevin will treat you right. Tell him Bob R. sent you.

[Sloter]

When your rotating lanes, there is no need for equal length lanes. What is more important is the design of the track, smooth flowing lines so you have less deslots and improved racing.

 

Bob

[Dave Crevie]

To try to illustrate what happens when using a pin guide for routing corners;

 

 

Where "B" is the desired lane spacing, starting with a completed curved outside slot "C", using a pin guide to route the next slot inward, will create an error in the lane spacing "B", and in turn a shorter radius "A" than intended. 

 

Conversely, starting from the innermost lane, using a pin guide to route the next lane outwards will create a lane spacing shorter than intended, and in turn, a smaller radius for that lane. In both cases, you end up with a miss-match where the curve joins up with the straight section just as Mike showed. 

 

I've seen guys use a 1/8th thick strip of teflon or nylon inserted into the slot to be copied, and a circular base plate for the router that has the lane spacing figured into the distance from the bit to the outside edge of the base plate. This way the lane spacing can be kept constant. This system is shown in one of the links in Jim's post. 

[MSwiss]

I'm surprised how many new people walk in my raceway and one of the first things they say when they see my flat track is ;  "How do you have races when the lanes are different lengths?"

 

When I explain that the races are all the racers running on all the lanes, they sometimes seem disappointed that they didn't detect a flaw in slot racing. Lol

 

On my track,  the shortest lane, is also the slowest.

 

Anyway, the OP has already stated he's not concerned with his unequal lap lengths. 

[MSwiss]

Thanks for the suggestions. 

 

Question: Is a 3.5" outer turn gutter enough width for 1/32 cars (5" to 6" long) or is 4.5" the way to go. 

 

I would rather not have the tail end of the cars scubbing the outer turn fence. 

 

I thought about the straight line router fence board to connect the turn lane slots to get the outer lane slot started.  The use of a router jig to cut the remaining slots.  I was going to test cut my small radius turns on some scrap with different jig pin spacing to eliminate that jog and good entry/exit geometry.

I'm skeptical you won't be stymied by that 4" radius, inside turn.

 

I'm sure I tried my jig with the cam rollers in the position shown and before I even turned on the router I could feel that the stability was inadequate.

 

You are going to need to cut the shape of the track out with a compass arm, anyway. 

 

I would just use it for everything. 

 

[Dave Crevie]

Exactly. The best method I've seen. 

[MSwiss]

As far as aprons for 1/32 cars, I would go with 5", minimum.

 

[Bigdogbro1]

I need to clarify that this is a 1/32 four lane track with the inner and outer lines being the track walls.  The smallest radius I have for a slot is 7.5" not 4". 

The outside gutter on all the turns is 4.5" with 3.5" lane spacing. 

Thanks!

I'm skeptical you won't be stymied by that 4" radius, inside turn.

 

I'm sure I tried my jig with the cam rollers in the position shown and before I even turned on the router I could feel that the stability was inadequate.

 

You are going to need to cut the shape of the track out with a compass arm, anyway. 

 

I would just use it for everything. 

 

Screenshot_20240424_111744_Gallery.jpg

Attached Images

• 

[Bigdogbro1]

I have updated the track design and adopted the idea of having a 5" slot spacing outer curve gutter to the track wall.  That will make the overall track wall to wall width at 19".  I can accommodate this in my track space.  Have been listening to all your comments and see the difference in a router slot spacer jig and a router circle cutter jig.   Using the router slot spacer jig has some slot turn curve lead-in and exit advantages and true radius arc disadvantages as well.  The router circle jig can do the curves but can have a more abrupt slot turn curve lead-in.  I am not yet clearly seeing a good manual method to creating these turns with the change in the tangent points (circled) when routing.  How does one know where to stop routing the slot to not overshoot the straightaway slot match-up.  I have never needed to fabricate anything such as this before and I'm at a loss on what is the best for geometry and fabrication.  Maybe partly routed with a router slot spacer jig and a router circle jig, I just don't know yet.  Please keep your thoughts coming.  Thanks!

Attached Images

• 
• 

[Eddie Fleming]

I have never built a track so I cant contribute much to the conversation.

 

This is just a question. If you use a router guide spacer to cut the curves would it be an improvement to to use a guide with one pin even with the router bit and one trailing rather than one ahead of and one behind the bit? I know this shortens up the spacing between the guide pins therefore making it less stable, but it seems the amount of change in curve radius would be smaller.

[Paul Menkens]

"How does one know where to stop routing the slot to not overshoot the straightaway slot match-up." don't worry about it, in fact, go an inch or two beyond where you think it should be, when you route the straights it will be easy to see where they need to join up with the curve without any "jog" when you're done you fill in the extra curve with Bondo or wood putty. When I finished routing my curves I placed a router in the spot where the exit from one curve was and another at the spot where the entrance of the next one was (very carefully) when I had it perfect I laid the straightedge down between the routers and when that was perfect I fastened it down with small finishing nails ( small so the hole in the track surface would be minimal) then routed the straight, it matched up perfectly. As far as the lead into the curve being abrupt that shouldn't be a problem, we raced Gp 12 and Gp 20 cars with no problems.

[Dave Crevie]

Before you cut any material, layout the entire slot path with a magic marker. Mark the endpoints of each slot, preferrably with a different color. The endpoints of the curved slots can be marked using a carpenter's square, one leg aligned with the straight section of the outer lane, and the other aligned with the center point of that curve. Using the leg of the square that passes through the center point, draw a line from that point out to the slot of the outer lane. (shown in red)  This will be the stop point of the curved slots. 

 

 

 

For two curves that meet without a straight between them, simply draw a line through the two centerpoints of the curves using a straightedge. 

[Bigdogbro1]

Dave,  Thanks for the diagram and the method!

 

I somewhat have started with that method and here is the layout. 

 

Should I use a router compass jig for the outer track edge profile?

 

Should I use a router compass jig to cut the four slots OR use the router spacing jig with a straight edge to finish the straightaways on either method? 

 

I assume that this is all after the unslotted track surface is assembled and before the the inner turn pivot points are cut out?

Attached Images

•