Me and my team have been working ruthlessly over the past 2 weeks trying to make our shooter work the best we can. We are using a linear shooter with 2 andymark 8in rubber tread wheels on a mini cim each. We finally got it shooting decently(shooting from the back of the pyramid near the center of the field and only just making it into the 3pt goal) by putting surgical tubing around the wheels to make them like pneumatic wheels for grip and compression. This worked fairly well except that the tubing expands an awful lot and wears down to quicky. We have been experimenting with different ways of getting the same result as the surgical tubing that just doesnt wear as quicky but are at a loss, so we were wondering what you guys have been using on your wheels(if any)?
It appears you are wanting more compression as if you had pneumatic wheels. Why not put the compressible material on your stationary wall opposite the wheel?
We tried that today by using weather stripping however are results went from the 17 feet or so to 2 feet.
What does the wall look like opposite the shooter wheel? Are you using any form of grip tape? The KoP grip material works excellent.
A photo might help out here.
A picture would be good, a video even better.
-First off, are you saying you shot multiple (i.e. minimum 5) and they went approx the same spot 17ft away, then another minimum of 5 discs with the weather strip and they all landed at approx the same place 2ft away?
-With the weatherstrip, did you play with the compression? Do you have the ability to move the wall opposite your wheel to have any compression you like?
Yes that is how we tested
http://sphotos-f.ak.fbcdn.net/hphotos-ak-ash4/487643_481295231935325_1236234744_n.jpg
This here is it at an earlier stage in development however all we did after this was reduce weight, the rear wheel no longer has surgical tubing on it as when they both expanded they rubbed against each other, 2 mini cims now, and we have a Lexan top to prevent ride up of Frisbees. Unfortunately I don’t have any recent pics:( . We will have a look into the KOP grip material. Unfortunately it is march break for us and we don’t have access to our shop so no further testing can be done for a week:( . We did play with the compression as well with our adjustable wall
My suggestions:
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get rid of the surgical tubing just to remove that as a variable (for this test anyways)
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try (insert compressible material here) on the wall
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play with the compression through a full range of barely grabs the disc to “whoa, you sure you want to compress the disc that much”?
-always shoot enough that you KNOW it is repeatably bad before moving on
repeat 2 & 3 with different materials
The disc slipping on the wheel AND the disc slipping on the wall are different variables and you will want to have an grasp on their effects to your shot.
This will not help with distance because the point of having a compressible material is to increase the time and amount of frisbee in contact with the wheel. If you don’t make the wheel compressible, the frisbee will only touch at that one point where it and the wheel are tangent.
Have you actuallytried a compressible wall?
I believe the fact that you are also storing energy in the frisbee when you compress it can also have an effect on distance.
The problem is, any change you make you have to go through the tweaking process over again, how bad is the ware rate? how many Frisbees can you shoot before having to change the tubing?
cheers
arun
We can get about 50 shots on 1 wheel. We don’t think this is that bad as one of our old prototypes needed to be changed every 2-3. The issue is that it takes to long to go and change our wheel(about 10 minutes which is no good in eliminations). Can anyone think of a material that can act like the tubing but more durable? We are currently thinking of using andymark tread instead . Ill be looking around in Toronto tomorrow for insparation.
one quick change you can make is make the wall flexible - so maybe thin gauge metal only fastened on two points - for a rubber-band effect, replicates to some extent what pneumatics do.
Somthing like:
but with only two hold-downs - the tension follows the Frisbee.
also you can try cutting up the latex and riveting it on - maybe that helps because it will reduce movement of the latex.
cheers
arun
Please also remember ::safety:: safety when you talk about attaching things to wheels that are already spinning beyond what they’re designed for.
a little searching and you can find a pic on CD of what happens when tread separates from a wheel by pulling out of its rivets, but don’t if you have a weak stomach.
Stay far from the plane of the wheel (“plane of death”, “plane of destruction”), and use guards if you’re going to experiment further with (cough) re-inventing the wheel.
Can’t believe this hasn’t been suggested yet, but if you can get these in time…
http://www.andymark.com/product-p/am-0970.htm
Problem solved. Same size, you get the compression you need (even variable to some extent as you can play with the pressure of the wheels), and it should mount on the existing hole pattern of the wheels you’re currently using.
used that wedgetop tread that you can buy from andymark on a 6" performance wheel. we also put that same material on our wall that is 1/8 thick lexan. it seems to work pretty good.
These are what we were going to use originally however one of our mentors mentioned that people have found that by spinning them at the 6000rpm we are that they will explode. This is what made us think of surgical tubing to get similar results. Also those weigh .5lbs heavier than our current wheels and we need as much weight reduced as possible to prevent being overweight. If it weren’t for this problem we would put them on, as we have 2 lying around the shop.
We went through the same issues. Spent big bucks on pneumatic wheels, etc. and ended up using an adhesive non slip rubberized tape on our wheels. Glued it down with industrial strength super glue and it works just fine. We put a small (thin) piece of the same material on the opposite wall. We made it a bit longer than the wheel’s contact space. It too works great. Got the stuff at home depot. The glue is some I use for my wargame miniature construction.
Do you have a link or picture of this material you have put on your wheels? Is it like the non-slip material you put under a rug or more like what you would find on the step of a ladder. This type of solution is exactly what we need we just haven’t found a material yet. How much compression did you have on the Frisbee(if any)? Also what kind of results were you getting; 10ft, 20ft 30ft…?
We are using the pneumatic wheels on our shooter with no problems.
We made two modifications to the wheels to ensure long wheel life:
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We balanced the wheels. We placed two 10-32 x 1.75" long screws in the hub slot opposite the valve stem, held in by foam sticky tape placed into each corner of the slot on the rim side. (Don’t worry, the foam is compressed when the wheel spins up, so they don’t get loose.)
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We added a carved oak block between the valve stem and the rim to keep it from flexing when spun.
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We support the wheel from both ends of the hub with a 3/8" bolt attached to the shooter frame, poking into a bearing pressed into the hub on the side away from the motor.
We can shoot pretty well into the 3 point goal at 50 feet. (Our testing was outdoors during a wind storm, so the average wasn’t that great.)