21 replies to this topic

[hoffmanbrent]

I'm wanting to build a 27.5 FT drag track in garage with limited space. looks like i would only have 5 to 7 ft shutdown area. What can i do to make that distance enough for stopping? I dont plan to use glue anywhere on track. current  1/24 cars have detroit hustler and proslot 550. i had one idea, but dont know if it be bad for the motors. have the shutdwon braids seperate with a low voltage applied to it with opposite polarity. Whats you guys thoughts. Thanks.

[MSwiss]

I've run 4V reverse voltage on my strip, to activate the warning lights on the end.

To tell the truth, on my 1/4 mile, it doesn't do much more than just shorting the braid.

Maybe on an 1/8 mile, you'll have a bit better luck.

I don't see any way you are going to stop a car, with motors that fast, in that short of a distance, without glue.

[Eddie Fleming]

How about running the track up the wall at the end of the strip? Could even make it a loop and let then fall in a net if they get that far.

[MSwiss]

There was a raceway in this area, that tried that.

I saw it, but never saw a car make a pass.

Larry Kelley talks about it.

IIRC, he said it didn't work very well, and may of added how the chassis got tweaked every pass.

[jimht]

2 airbags (garbage sack in a pillowcase) in a box with a small (processor) fan to keep them softly inflated.

[Dan Ebert]

Anything over 25 mph will not stop in 8 feet.  Good luck.

[Dave Crevie]

You really won't get away with anything less than 8 feet. I had 7 feet on my 1000 scale foot in 1/24th, 1/4 mile in 1/32nd strip, and needed a capture box at the end to catch the cars. The box was filled with soft bath towels, and some cars still hit hard enough to knock off some details. 

[hoffmanbrent]

Thanks for the information so far

[Phil Smith]

Have a capture cable similar to what aircraft carriers have. It might not work, but the failures would be epic!

[MSwiss]

2 airbags (garbage sack in a pillowcase) in a box with a small (processor) fan to keep them softly inflated.

Interesting idea.

Have you done it, or seen it done?


To the OP, what's the reasoning behind no glue anywhere on the track?

[Bags]

Drag strips have shutdown area’s that require glue to stop the cars. They also have a secondary stopping “thing “ 

at the end of the track be it a pillow , foam, an old bed sheet wadded up anything to keep the car from falling off the end.
 

4-5 feet of shutdown won’t stop hardly any car even with glue.

No glue won’t end well.

 

Keep em Green

Bags

[Alchemist]

San Francisco Ocean Beach Playland Model Car Raceway (whew!) employed an authentic parachute at the end of the strip with no glue at the strip end.

 

I do recall at one time, thick soft foam blocks were added underneath the parachute and positioned at the track end barrier wall, because some cars were getting thru the bunched up material of the parachute and slamming into the barrier wall with the obvious negative results!

 

I just thought I'd share that info.

 

Best of luck in coming to a successful solution!

 

Thank you.

 

Ernie

[Dave Crevie]

Dragstrips in the '60s used government surplus parachutes for shut downs. They were made of silk, and were damned cheap. $5 at the Army-Navy store in my town. They were real popular with the lady crafters in the area, most churches having groups of quilters. The 'chutes were cut into squares, each one being hand embroidered with a design, then sewn into a quilt. My mother belonged to one at our church, and got a quilt that was on my bed from when I was a very small child right through high school. I think it unlikely you will find a silk parachute these days, though. 

[old & gray]

Dragstrips in the '60s used government surplus parachutes for shut downs. They were made of silk, and were damned cheap. $5 at the Army-Navy store in my town. They were real popular with the lady crafters in the area, most churches having groups of quilters. The 'chutes were cut into squares, each one being hand embroidered with a design, then sewn into a quilt. My mother belonged to one at our church, and got a quilt that was on my bed from when I was a very small child right through high school. I think it unlikely you will find a silk parachute these days, though. 

 

After World War 2 a number of silk wedding dresses were made from surplus parachutes.

 

Swords to Plowshares. 

[Thom]

PM

[Mr Nobody]

Would full brakes on a good controller stop a drag car in 7ft? I’m not sure how fast these cars are going, I’m just thinking it stops pretty fast cars on a regular track within that distance.

[jimht]

Mike Swiss: "Have you done it, or seen it done?"

 

Yes, on my scale 1/4" mile when I was subleasing inside Malibu Gran Prix in the 1990's (with 20' of shut down). Considering how short his strip is it would probably stop the cars without much damage.

 

I've also used magnetic braking but we don't want to go there because that's not real slot car racing.   

[MSwiss]

You already had 20 ft., which is pretty normal for a 1/4.

Did you glue that 20'?

Magnets would probably work great, if the OP was willing to build specialized cars, or modify existing ones, to suit.

[jimht]

The shutdown was tacky but that was from the glue used on the tires at the start.

The airbags would stop the cars with no damage except for punching holes in garbage sacks which is why the plastic sack was inside a cloth bag.

Magnetic braking combined with airbags is what I finally wound up with.

 

Using glue with narrow drag tires is like trying to stop a bicycle wheel with a thin layer of mud, no surface area to grab, if it sinks it stops, otherwise the amounts of glue necessary are unbelievable and the glue keeps getting carried back to the start on the tires, making a goopy mess at both ends of the track.

 

Magnetic braking using 1/16" thick servo tape to attach 1/2" wide steel banding strip on either side of the braid shoulder in the shut down works OK and requires a couple of thin magnets taped to the bottom of the car.

[hoffmanbrent]

Mswiss

 

I say no to glue with my only experience being with my mock up track to sort out the electronics of the starting / timing system. I've been only once to a legit track to watch. prepping the lanes between rounds seem like a slow down for me, although i do understand that's part of getting your car down the track consistently.

I'm all ready seeing the issue of stopping with my little mock up track. Because I'm doing this in a room in the house, I'm using a 4ft TFL board, with a race length of only 19 inches. the 19 inches consist of about 3 inch under power and 16 inches of coasting. ETs are in the .225 second range, cant compare that to anything cuz cars are coasting well before finish line sensor.

. 

[Bags]

Brent  it only takes 60-90 seconds to clean the starting line. With the bracket paring  programs that are available that already have a built in clock it should not be a slow down at all as you put it. You are going to have to stop the cars one way or another. Glue has been used in shut downs as long as there have been slot drags. Coleman fuel in a spray bottle and a rag at the starting line is all you’ll need to clean it. Let it dry push the car thru a couple of times stage and go.

 

Keep em Green

Bags

[hoffmanbrent]

I'm not using any computer/software. I have designed and built the Christmas tree and timing system with TTL ic chips.
Current plan is build the shutdown section so that it can easily attach/detached to the finish line. We will just open garage door. Of course this winter have to come up with other idea, like glue and/or shorten track.