59 replies to this topic
Posted 14 December 2007 - 07:29 PM
I have an idea for a test tank and would like some imput please.
I cut a plastic 55 gal drum in half and I am wanting to add a discharge hose, pump and a inlet hose to create water flow.
I'm thinking the hoses should be straight across from each other with the discharge on the bottom and the inlet at the top below the water line.
My questions are would you be able to control the flow enough to gauge the action of a bait?(by pump size and a gate valve)
What size pump and hoses?
Has anyone tried this before and does anyone have any suggestions?
thanks for your help and for a great site.
Good Luck Fishing
Posted 15 December 2007 - 12:35 AM
I like your idea, if it works it would save a lot of time and gas going to the lake to test. Maybe a pump and a few jets from a Hot tub put on the end would create enough flow. Keep us posted on this.
Posted 15 December 2007 - 03:44 AM
I have a simple spread sheet that calculates the flow rates required for various sizes of half pipe and square sections at various speeds. Metric and imperial! This information will help you choose a pump for the job, removing some of the trial and error.
A lipped lure has a minimum speed before the action starts. This is about 0.5m/s or 1.5 ft/s.
Whether a straight inlet and outlet system will work, you will have to build one to find out. My thoughts when I was planning the same thing, was laminar flow is the ideal test conditions. The inlet and outlets are going disturb the flow dramatically, probably a high speed jet up the middle and static water at the sides. To counter this effect, a series of baffles at each end, to even out the flow would be required. This would mean a longer tank length to accomodate the baffles.
The best plan would be to decide on the length and width you want to work with. Using this information and the data sheet, select a pump that is capable of exceeding the figures in the data sheet and see if such a beast is available at the right price.
As for the baffle design, I have no idea, but I'm sure we could work it out. PM me with your e-mail address and I will send you the spread sheet.
Posted 15 December 2007 - 04:19 AM
Todd- the test tanks I have seen are circular, about 6’. The have a paddle wheel in the middle with a geared slow revving motor which is speed regulated. They turn the motor/paddle on and gradually the water circulates around the tank until it reaches the desired speed. Once the water is moving there is very little load on the motor.
You could probably do it easier with a small bilge pump and introduce the water in the side and parallel to it. Speed could be regulated by a valve on the pressure side of the pump (restricting flow from a centrifugal pump will not damage it). If you want to try this, get in a small, round, above ground swimming pool (12’), get out on the perimeter and walk around the pool a couple of times, stop and you will realize how much flow you have generated, it will probably knock you over. Excuse my drawing, done it in a hurry. pete
Posted 15 December 2007 - 06:09 AM
If you wanted to get a durable tank, a round, galvanized stock tank would be worth thinking about. Tractor Supply has a 6' x 2' galvanized tank for under $200.00. They make them in plastic to, but the oil prices are, the galvanized steel would probably be cheaper.
Posted 15 December 2007 - 07:29 AM
spike a pike is right i have had a galvanized tank for about two years and it saves alot of time you dont have to run to the lake all of the time and it works great and i dont have any pumps to create current just pull your crankbait on a small rod works for me:)
Posted 15 December 2007 - 07:36 AM
If somebody really wanted to all out, they could mount a motor over the center of the tank with a rod to pull the test bait. That would leave at least one more hand free for a beer.
Posted 15 December 2007 - 07:45 AM
beer and my lab jumping in. hes a wood tester. sorry i could not resist
Posted 15 December 2007 - 07:48 AM
I think Pete's circular tank is the way to go.
I don't know about TC, but when I was considering my options, it was to be able to video the action. It all happens so fast, it would be nice to slow it all down to study.
Posted 15 December 2007 - 06:56 PM
Thanks for eveyones help.
I think Pete has the way to go, I am off the week after Christmas and am planning on working on it then.
I will let you know how it turns out.
thanks again Todd
Posted 15 December 2007 - 11:18 PM
Todd. I was thinking, if you had a swimming pool to do that 'swim' test in, you would not be asking 'How to build a test tank'. pete
Posted 16 December 2007 - 02:07 AM
Tater Hog mentioned that he recently bought a cow watering trough for about $100 for the same purpose.
Posted 16 December 2007 - 08:21 PM
What do you city guys think a galvanized stock tank... you can check 'em out on the tractor supply store on da web.
Posted 16 December 2007 - 09:03 PM
Would you need to have a straight section so the velocity of the water the lure is sitting in is uniform? I was just wondering if lure action would be affected by placing it in a flow along a curved path (like water flowing around a 55 gallon drum). Just curious.
Posted 17 December 2007 - 02:31 AM
I am sure I saw Rapala using circular tanks (years ago), probably before they could afford the comparativley huge pumps needed to get the through flow in rectangular tank ** I don't know??? pete
Posted 17 December 2007 - 03:05 AM
I cannot see a problem with a circular tank. The most important thing is that the flow is constant and uniform or laminar. The larger the diameter, the less the curvature will effect things.
If it is the intention to use the tank to tune the lures for straight running prior to delivery, this could cause a slight problem. But by running a perfectly tuned lure first, would show if the tuned lure runs to one side or not. You just need to tune to the same pattern. I didn't explain that very well!
I agree with Pete, the power to push the required volume of water through a straight pipe is large in comparison to the motor required to drive the circular tank.
Posted 17 December 2007 - 03:39 AM
Good ideas everyone. LaPala's thread "Lure Making Videos" shows video of a Rapala lure testing tank in action at their facility in Estonia. Might be helpful, looks pretty simple to implement.
When I test lures, I need to be able to test them at a variety of speeds-- from dead slow to quite fast. The straight tank setup Rapala uses allows for this. I suspect that the test parameters you subject your lures to would largely determine whether a round or straight tank works best for you.
Here's the video: http://www.tackleund...ead.php?t=10964
Posted 17 December 2007 - 03:46 AM
I wish I could view the vids, something is not set up right on my laptop. I'll have to take it to the shop one day, unless one of you guru's can make a suggestion.
Posted 17 December 2007 - 03:56 AM
Well there you go- of course, we don't need any flow at all, funny how I can make mountains out of mole hills. Thanks Sagacious.pete
Posted 17 December 2007 - 07:50 AM
I our part of the country they use discarded bath tubs as stock tanks. Why wouldn't the bath tub work for a test tank.
I can hardly wait for your comments on the bath tub idea.