# Crankbait Testing



## goolies (Jun 28, 2007)

I'm toying with the idea of building something to test the action of cranks and I have a question. If you were only interested in seeing the action of a crank and not in seeing it's diving depth, what size water channel would you need? Minimum width and minimum depth? I was thinking 5-6 inches wide and 5-6 inches deep. I would be interested in other opinions.


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## AtticaFish (Nov 23, 2008)

Don't think 5"-6" width will be a problem if they are tuned right. Just about any crank will run at least 6" deep and will bump the bottom and change it's action. Think you will need to go deeper. Maybe a 10-20 gal fish tank but not sure how you could get any flow.
Thats my thought.


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## goolies (Jun 28, 2007)

AtticaFish said:


> Don't think 5"-6" width will be a problem if they are tuned right. Just about any crank will run at least 6" deep and will bump the bottom and change it's action. Think you will need to go deeper. Maybe a 10-20 gal fish tank but not sure how you could get any flow.
> Thats my thought.


The diving depth of the crankbait can be kept shallow by making the tow line short (6-12" in length).


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## napsax (Feb 15, 2008)

Sounds like the fish tank idea would work alright. I would be more interested in the leader length you'd use once you established a decent flow. Divers would have to be restricted to a short leader & lower flow for observation. Good luck. Sounds like a potentially lucrative product once developed. I've seen something like it at the Travel Boat & Fishing Show in Cincinnati. It was used to display jig & worm action.


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## rjbass (Aug 1, 2007)

Check this out....here is one of rapala's test tanks....nothing fancy all by hand. Works for them......


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## goolies (Jun 28, 2007)

rjbass said:


> Check this out....here is one of rapala's test tanks....nothing fancy all by hand. Works for them......



Thanks Rod, but a 500 gallon tank may take up to much room in the garage.


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## rjbass (Aug 1, 2007)

Here is what we use, does not really take up that much room....works great.

http://lawn-and-garden.hardwarestore.com/39-472-stock-tanks/galvanized-stock-tank-616176.aspx

Rod


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## goolies (Jun 28, 2007)

Thanks Rod.


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## chappy (Aug 16, 2006)

Andy I have a 125 gal fish tank i've been trying to sell 6'longx18" wide


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## goolies (Jun 28, 2007)

Thanks for the offer on the tank chappy. I really want to focus on building a system with flowing water instead of a tank where I need to drag the lure. I want to be able to consistently reproduce lure speeds while making observations and taking measurements. Dragging lures at 1.5 ft/sec (1 mph) to 4.5 ft/sec (3 mph) by hand makes that difficult. If you haven't noticed I'm more into the science and engineering side of lure design than the artistic part.


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## socdad (Jul 25, 2005)

Sounds like you are looking for a 30 gal (or so) tank. You might look for a breeder tank. These tanks have a rectangular footprint; however they are usually only a 5-10 inches tall. All youll need to do is put a power head in one end and watch the water run  (One source for the power head is http://www.aquariumguys.com/waterpumps1.html)


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## hazmail (Oct 26, 2007)

Goolies - about a year ago, this was brainstormed on TU, and quite a few left field ideas came out of it-
See here.pete
http://www.tackleunderground.com/forum/hard-baits/11085-test-tank.html


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## goolies (Jun 28, 2007)

hazmail said:


> Goolies - about a year ago, this was brainstormed on TU, and quite a few left field ideas came out of it-
> See here.pete
> http://www.tackleunderground.com/forum/hard-baits/11085-test-tank.html


Thanks Pete. I'm very familiar with that thread. It's a very interesting discussion. I started this thread here to get opinions on what size water channel would be needed to effectively test the action of a lure (not diving depth). Do you have an opinion? Width? Depth? I have narrowed my ideas for possible ways to do it down to 3 and will most likely build something before this winter is over.

Andy


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## hazmail (Oct 26, 2007)

Goolies - Here is 3 addresses, one each in Canada, U.S and Australia, all are pretty large setups, but I suppose you could scale them down a bit. The common thing in all three is a large reservoir of water flowing through a narrow neck into a receiver tank (downstream), speed of flow seems to be regulated by how much is pumped from the reciever back to the reservoir. This (Speed) could be esaily controlled by having a valve on the inlet side of the recirculating pump.pete
http://iar-ira.nrc-cnrc.gc.ca/aero/aero_8f_e.html

http://www.rollinghillsresearch.com/Water_Tunnels/Model_0710.html

http://www.dsto.defence.gov.au/research/5108/


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## goolies (Jun 28, 2007)

hazmail said:


> Goolies - Here is 3 addresses, one each in Canada, U.S and Australia, all are pretty large setups, but I suppose you could scale them down a bit. The common thing in all three is a large reservoir of water flowing through a narrow neck into a receiver tank (downstream), speed of flow seems to be regulated by how much is pumped from the reciever back to the reservoir. This (Speed) could be esaily controlled by having a valve on the inlet side of the recirculating pump.pete
> http://iar-ira.nrc-cnrc.gc.ca/aero/aero_8f_e.html
> 
> http://www.rollinghillsresearch.com/Water_Tunnels/Model_0710.html
> ...


Neat stuff Pete. It's funny that one of my 3 ideas that I'm still cosidering is very similar to what is shown in these links. I have sketched an idea to connect to small tanks up high with a testing channel. The water would be pumped from one tank to the other via a pipe. A valve on the outlet side of the pump would be used to throttle flow. The changing water levels in the tanks would create flow in the channel. It is one of my simpler ideas and probably the one with the least risk of failure. The only problem is that a 5" wide by 5" deep test channel flowing at a velocity 2.5 mph requires a pump capable of producing 285 gpm. The only way to get that kind of flow at an affordable price will be a pump powered by a small gasoline engine. I have not ruled this out but it would not be ideal for use in a garage.


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## hazmail (Oct 26, 2007)

Gee Goolies, 285 g/min (1200 l/min or about 2/3 of a ton)) sounds like a lot of water, the biggest fire pump we have around here does 3200 l/min. I am going to have to go back to fire school and get my 'pump sums' out, surely we can do better than that. pete


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## goolies (Jun 28, 2007)

Area x Velocity = Volumetric Flow Rate

5 in. x 5 in. x 2.5 miles/hour x 63360 in/1 mile x 1 hour/60 min x 1 gallon/231 cubic in. = 285.7 gal/min

Yep. It's a lot of water Pete. That why I was asking everyone for their opinion on water test channel size. If I go with a water test channel 5 inches wide and only 4 inches deep I can get the water flow down to about 229 gallons per minutes. Here's a link to the pump I found. It has a 6.5 HP engine to develop that kind of flow.

http://www.duropower.com/item.asp?PID=184&FID=8&level=1


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## hazmail (Oct 26, 2007)

Goolies - I got the young guys here to work it out, and they concurr with yours ( in metric of course), still can't believe the volume!! How about the circular tank with a pump idea?? Variable speed (from centre outwards), years back I saw Rapala was using one with a water wheel in the middle, and motor suspended above (tank was about 6'-8' dia x 18" deep).pete


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## goolies (Jun 28, 2007)

hazmail said:


> Goolies - I got the young guys here to work it out, and they concurr with yours ( in metric of course), still can't believe the volume!! How about the circular tank with a pump idea?? Variable speed (from centre outwards), years back I saw Rapala was using one with a water wheel in the middle, and motor suspended above (tank was about 6'-8' dia x 18" deep).pete


I posted a similar concept in the test tank thread on Tackle Underground. An oval test channel with a means of simply circulating the water around. This would allow you to take advantage of the momentum of the water and reduce your overall power requirements. This is the concept I would really like to pursue because I have an idea for a water circulating device that should only require a 1/4 HP to 1/2 HP electric motor. I prefer an oval test channel with a stretch of straight flow over a circular tank. Something about the constant circular flow just doesn't seem right. I'm not sure how that might affect the action of the lure. I think it would need to be very large in diameter. Maybe that is why Rapalas tank was so large. Not really a bench top tester.


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## hazmail (Oct 26, 2007)

I played around with the wind tunell thing for a while, all I could get was 'death spirals'- Keep us posted, there seems to be a large core group of people looking for the 'Shangrilah' of test tanks.pete


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## AtticaFish (Nov 23, 2008)

All right.. I'm not quite as scientific as ya'll sound but... what if you made a V shaped channel? You would be pumping less water than a circular wouldn't you? It may take the same pressure/flow rate (whatever?) but would think it would take a much smaller reservoir of water to run.

Nother layman's question... what effect does gravity have? If you sloped you whole design would you get greater flow??

I have recently been carving my own crankbaits from balsa. Not large scale, mostly pretty small for crappie. Some of the flat faced lipless baits I have made have a very large side to side wobble. I think your width size will depend on the overall action of your bait. I'd go slightly wider than what you think is too much wobble. If it hits the edge... it aint workin right.

Post when you discover eden... would like to scale down whatever you come up with for crappie baits. Good Luck!


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## goolies (Jun 28, 2007)

AtticaFish said:


> All right.. I'm not quite as scientific as ya'll sound but... what if you made a V shaped channel? You would be pumping less water than a circular wouldn't you? It may take the same pressure/flow rate (whatever?) but would think it would take a much smaller reservoir of water to run.
> 
> Nother layman's question... what effect does gravity have? If you sloped you whole design would you get greater flow??
> 
> ...


Thanks for your reply AtticaFish. The V shaped channel might reduce overall flow requirements and it might not. You correctly noted in your reply that the lure needs room to wiggle without hitting the sides of the channel. As a lure goes below the surface in a V shaped channel the sides of the channel get closer to the lure. With that said the top of the V channel may need to be larger than the top of a U channel to get the lure to the same depth. What about an inverted V (^) or a rhombus with the top being narrower than the bottom? I definitely need to put more thought into the test channel shape and size.

I have considered whether or not I could utilize gravity in building a lure tester. Unless you have very large tanks you will still need to pump the water from the recieving tank to the starting tank to keep up with the flow requirements.

If I build something I will post the results here.


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## tomb (Oct 9, 2004)

> 5 in. x 5 in. x 2.5 miles/hour x 63360 in/1 mile x 1 hour/60 min x 1 gallon/231 cubic in. = 285.7 gal/min


Andy, that works out to 17,142 gal/hr! Is that right? It just doesn't seem right.


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## tomb (Oct 9, 2004)

Using this formula http://www.engineersedge.com/fluid_flow/volumeetric_flow_rate.htm

A 5"x5" channel moving at 1mph works out like this:

.4166666' x.4166666' x 1.5ft/sec= .260cu ft/sec. Which equals about 7000 gph!! I can't believe such a tiny channel flows that much water so quickly. I'm a little rusty on my math, and was hoping I made a mistake somewhere.

This pump supplies that much water, sure is a steep price for this application though. If I still had my reef tank up and going I'd pay this, but not to test lures.

http://www.marinedepot.com/ps_ViewI...twater_Aquarium_Supplies&vendor=&child=DP7565

What really sucks is that you'll need three of them to hit three mph


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## goolies (Jun 28, 2007)

Tom,

Your math is correct. Most people don't realize how much water is required to test a lure. Even if you pull the lure in the water. 1 mph = 1.5 ft/sec. If I want to watch a lure for 2 seconds moving at 2.5 mph I would need a tank about 8 ft long.

Andy


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