Track and lane change experiments

Questions and Ideas to track building, how are you doing it? need help? new features? share your ideas.
WesR
Posts: 371
Joined: Fri 21. Dec 2012 17:37

Track and lane change experiments

Post by WesR »

DSCF9733 (479x500).jpg
DSCF9733 (479x500).jpg (219.51 KiB) Viewed 17518 times
This is a test track using .5mm (.020") diam. wire. The point of using thinner wire is that it can easily be laid out on a smooth base and cars will run over the wire at l/c points, etc., and the track can be tested without the need for routing or plaster filling. L/cs can be modified, radii changed, etc. very easily.
There is of course less magnetic guidance but I have found that this is mostly made up by the fact that, gluing to a perfectly flat baseboard such as MDF (medium density fibreboard) gives a very accurate track and the guide magnet on the car can be set very close to the wire. Whilst searching for the wire I also located some flat steel strip wire 1/16" (1.5mm) wide x .007" (.2mm) thickness which of course would be even easier to drive across.
I laid an approx. 1 metre straight and one l/c. However I soon decided that, even with only 1.5mm, the guide magnet would wander from side to side and increase the possibility of cars fishtailing on the straight. Also this wire was difficult to curve around the bends.
This wire did prove to be just the right thickness for the lane change plates however.
WesR
Posts: 371
Joined: Fri 21. Dec 2012 17:37

Re: Track and lane change experiments

Post by WesR »

DSCF9740 (500x362).jpg
DSCF9740 (500x362).jpg (157.73 KiB) Viewed 17517 times
DSCF9734 (356x500).jpg
DSCF9734 (356x500).jpg (158.9 KiB) Viewed 17517 times
On this track I have tried a number of different l/c ideas. One aim was to be able to run in either direction. The first pic. shows, on the left, the flat wire section, and on the right a basic wire gap l/c. This does work well on the track but has, I feel, three disadvantages. If the straight were longer and the curve faster, the gap would probably need to be increased. Then, if you have a slower novice driver, the car might turn too soon and leave the track. Also, when running in the opposite direction, cars may leave the track. Also, if a novice driver turns the wrong way, the car will leave the track.
Second pic shows what you might call a 'catch' design in which the car turns across and is caught by the alternative wire.
This is working well and seems to work well with cars running the opposite way. If the steering is turned the wrong way, the car will leave the track.
Third pic. shows a conventional l/c using 2 strips of the flat wire. This probably gives the best overall result but does need more adjustment and accuracy than the catch wire idea.
The cars do not run perfectly over the wire and the track surface would need building up level. Whether several coats of paint would be enough I am not yet sure. Otherwise a thin skim of plaster will be needed.
Cars still run perfectly on our Linford track I would have to build a larger track to say whether any of these ideas are better or not.
Attachments
DSCF9719 (500x345).jpg
DSCF9719 (500x345).jpg (187.78 KiB) Viewed 17517 times
User avatar
HeliumFrog
Posts: 82
Joined: Tue 7. Oct 2014 22:28
Contact:

Re: Track and lane change experiments

Post by HeliumFrog »

Great Information for us all Wes.
I have tried a few configurations and having a gap in the wire does tend to make the cars fly off, particularly if the tracking of the steering is not so good or the drive from the rear wheels is a little uneven. I have found these problems when I make my own chassis and or use rubber rear tyres.

If my assumptions are correct the magnetic force will be linked to the cross section of the wire, so
0.7mm wire has a cross section of 0.384 sqmm (Standard Magracing recommendation)
0.5mm wire has a cross section of 0.196 sqmm (Your new experiments)

0.35mm x 2 has a cross section of 0.192 sqmm very similar and would be a lower profile. In fact as the section lies closer to the magnet, the adhesion may be greater allowing a thinner wire.
Perhaps two thinner wires side by side might be worth a try. I'm not sure how easy it would be to lay, but it might enable them to be split at the lane change so there is always at least one wire controlling the car. The magnetic force would reduce slightly but not completely under the car and may allow the steering to make the lane switch. Also how would the car run if presented with two wires a short distance apart? Would it track along the centre?

The last picture you showed with the lane plates you said worked the best. It would be nice if the main wire was continuous and the lane change plates were small triangles either side. If this could be done, it might be easier to set up the lane change at the correct angle.

Once again thanks for the effort you are putting in here.
kiklo
Administrator
Posts: 485
Joined: Mon 9. Nov 2015 11:49
Location: Norway
Contact:

Re: Track and lane change experiments

Post by kiklo »

I have also been playing with the catch wire idea, using 2, one extra on the open side to direct back if driver turn the wrong way. Still just an idea.
Racing Regards

Kim K.
WesR
Posts: 371
Joined: Fri 21. Dec 2012 17:37

Re: Track and lane change experiments

Post by WesR »

Hi Martin, pleased to hear that you are still enthusiastic! Re. twin wires, the problem I think would be that it is almost impossible the lay them at exactly the same height, even on a very smooth board, and the cars tend to follow the highest one, even if it is only a few thou higher.
With twin wire separated slightly, the car would not run down the middle but would follow one or the other wire.
The system is designed so that the steering coil does not have the power to overcome the guide magnet unless there is a gap in the wire, or a weaker magnetic effect such as a thinner wire/plate. The plate idea seems to work in that the magnet can be steered across the plate towards the new route but the edge of the plate seems to hold the magnet and stop the car leaving the track.
When racing, we found that it was important to be able to drive the cars across the wire to get back onto the track after an 'off'.
The .7mm wire seems to be about the largest diam. to enable this. As you have found, the system is based on a formula for guide wire, magnet, coil power and front and rear wheel grip. We decided to use non standard wheel sizes to discourage the use of rubber tyres etc. A small amount of extra grip on the rear seems ok but rubber tyres would probably need different lane changes. All good fun!
Smittoh
Posts: 19
Joined: Mon 29. Feb 2016 02:14
Location: Tucson, Arizona

Re: Track and lane change experiments

Post by Smittoh »

:lol: Dang...I kinda wished I'd read all of this before ordering wire for my future track.
That being said ....this is a hobby so I will do my best to track (so to speak ) the development of my first track. Many thanks to all those who post their work! Unfortunately my sad designs will likely prove to be experiments in failure or great learning opportunities(of what not to do...)
Keep in mind... I'm a terrible example of how to do things scientifically or perhaps better stated...precision oriented... I promise to try!
That being said....I really just want to take a bread dough roller and see if I can smash the wire into foam board ...lol
I'm sure to be a prime example of the quickest decent to failure... :lol:
Cheers!
Kiko-smith
Ned
Posts: 368
Joined: Sun 13. Apr 2014 01:02
Location: Sedona, AZ USA

Re: Track and lane change experiments

Post by Ned »

Are you planning to use XPS rigid foam insulation board? What thickness? You may be able to press the wire into the foam temporarily but the guide magnet of the car will pull it right out. I use 36" long pieces of .032" diameter music wire which can be purchased inexpensively at ACE Hardware. It's manufactured by K & S Precision Metals in Chicago, IL. I glue the wire into grooves (slots) I cut with a router bit.
For info on making a track from XPS foam board, see viewtopic.php?f=5&t=293

Originally I glued sections of track together using 8"-12" wide pieces of insulation board placed under the seam/joint. I don't recommend this now. Instead I suggest using truss connector plates like the one in the photo below along with lots of the appropriate glue, if the track is to be permanently installed somewhere.

Image
User avatar
HeliumFrog
Posts: 82
Joined: Tue 7. Oct 2014 22:28
Contact:

Re: Track and lane change experiments

Post by HeliumFrog »

Yes I think foam board might be a viable option. A Paper Mache layer (I used newspaper torn roughly and glued down with wallpaper paste) should keep the wire from coming up. It also makes a really nice textured surface to paint on.

MDF does have a hard surface so wouldn't work if scoring it with a knife. I also hate the stuff as it doesn't handle dampness very well and many people have tracks in the garage or shed where it can be damp (Well here in the UK its always damp!).
Plywood is a much softer material and I used this for my track. If the wire can be reduced in diameter as Wes is trying, the plywood could be scored with a sharp knife (maybe fastened through a block to give an even depth cut) and then the wire hammered home without glue. I actually tried this with 0.7mm and it did work, but was hard work and hammering in took effort. I do think the 0.5mm wire would work much better with this method. The only downside is the lane change plates, but maybe a thin sheet glued on top would be OK.
Smittoh
Posts: 19
Joined: Mon 29. Feb 2016 02:14
Location: Tucson, Arizona

Re: Track and lane change experiments

Post by Smittoh »

Thanks again for all the info.
Im excited about trying the xps board... will probably be a few weeks before supplies arrive.
Im also curious to see how my idea of adding small elevation changes work out and foresee possible problems in making sure the wire is inlayed consistently in shaped foam.
Will write more another time on the "my track" page as this thread is intended for lane change experiments and Im currently not contributing anything useful on the topic. :talk
Sorry about that!

Cheers! K
Kiko-smith
WesR
Posts: 371
Joined: Fri 21. Dec 2012 17:37

Re: Track and lane change experiments

Post by WesR »

The important point here is that the car magnet needs to run as close to the wire as possible, at all points on the track.
If the wire is low, in relation to the track surface, on a curve for instance, the car may loose guidance or, if low on a straight, fishtailing is more likely. If the wire is high at any point, the magnet will of course stick to it. So accuracy in laying the wire is all important. Glueing it to a perfectly flat surface like MDF board is almost 100% accurate. Hammering the wire into foam, etc., does not fill me with confidence!
Post Reply