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closetguy
Fireman
USA
1294 Posts |
 Posted - 06/24/2012 : 4:57:00 PM
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Hi All
It's been a while for posting any kind of project, but I've been fortunate to see a major increase in business and modeling has been second over the last 4 months.
I did however last Sunday get a bug up my butt to build my own static grass applicator. I have a buddy who owns the Noch unit and like others have said , It's just too much money.
I bought my wife one of those bug zappers last year and she never uses it. So I confiscated it.
I read everything here on the forums and scoured all the articles on the net and decided to attempt my own.
This was the first try.
I used a 4 1/2" diameter all metal sheave. The flyswatter used 2 "d" size batteries, so there is a good amount of current available to charge the grass. The biggest complaint I read was that it took a long time to charge the grass and get it to stand up. That was what happened with this first attempt. It took 5 to 10 seconds to get the grass to stand up completely and I had to hold the screen less than 1" away from the surface.
Not that happy with the results and decided to refine this to a better operating unit.
Mike M |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/24/2012 : 5:06:16 PM
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Hi All
So I spent some time mulling over the charging time and realized that screen size is important. None of the tutorials discuss screen size but looking at the Noch, its around 3". So I decided to try smaller screens. The bulk also bothered me. The larger screen doses not fit around smaller areas very well. So I found these on e-bay.
I choose the 3 1/4" first. I liked the long neck to allow easier access to tight area's
I cleaned up the handle a bit. Fit the longer neck in place and epoxied it in place. And ended up with this. I silver soldered the neg. wire to the screen and used a alligator clip for the pos. wire.
Mike M |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/24/2012 : 5:22:42 PM
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Hi Again
I had a supply of Silflor Static grass. On my list of projects was making trees the way Scotch Pine does. From what I read on-line most are not happy with the other brands of static grass. So I decided to try the Silflor. I had 2mm, 4mm, and 6mm handy. My first try was with Scenic cement. That sucked. I than tried diluted white glue. Nope. I bought a bottle of Matt Medium last year and its been sitting waiting to be used.
I used it undiluted.
The first was the 2mm grass.
Next was the 4mm
6mm
Application time was fast. 5 seconds. Distance from surface is about 1/2" . I'm going to try 1" next to see.
Here is 2mm and 4mm applied at the same time.
Mike M |
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milocomarty
Fireman
Netherlands
4927 Posts |
Posted - 06/24/2012 : 6:06:46 PM
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| Hi Mike, like the homebuild grassthing. You should give it a try with the bottom of the sieve flattened, gives more surface for the static energy.. |
Grtz Martin..
http://cardiganbaycoastalrailroad.wordpress.com/ |
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Mark R.
Engine Wiper
Canada
247 Posts |
Posted - 06/24/2012 : 7:01:45 PM
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Did you modify your circuitry in your fly-swatter to make the high powered version ? That makes a big difference. Another thing may be the fact the entire sifter including the handle is metal. The converted fly-swatters I've seen, use a plastic handled sifter with a metal screen.
Mark. |
Roach Custom Painting |
Edited by - Mark R. on 06/24/2012 7:02:38 PM |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/24/2012 : 11:00:45 PM
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Hi Mark
No I did not modify the swatter. This one used "d" size so It has a little more current. The larger sifter I first used seemed to have created to large of a weak field. The smaller sifter seems to create a smaller more powerful field. I just flattened the bottom a little as suggested by Martin and found I could hold it away from the surface 3/4" of an inch and could get 6mm grass to stand up.
Mike M |
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Mark R.
Engine Wiper
Canada
247 Posts |
Posted - 06/24/2012 : 11:14:15 PM
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The D battery has nothing to do with the current output - you'd get the same result using a AA battery .... it just wouldn't last as long ! The resistors on the circuit board are what is regulating the current output.
You really need to modify the circuit board (really simple) in order to get the best effect. Otherwise the unit has to be held rather close to get any effect .... even then it's somewhat minimal. Judging from your pictures, it doesn't look like much of any of the fibers are standing on end !
This is all you have to modify for the high powered version - Bridge the resistor in series with the capacitor (resistor A) with a bit of wire, and remove the resistor in parallel with the capacitor (resistor B) entirely.
Also, to get the most use out of your unit, replace the batteries with a 3 volt wall wart for unlimited use. Those batteries will fade rather quickly if you are using it constantly.
Mark. |
Roach Custom Painting |
Edited by - Mark R. on 06/24/2012 11:22:23 PM |
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SDFarmer
Section Hand
USA
59 Posts |
Posted - 06/25/2012 : 03:29:04 AM
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From my Basic Electricity electronics classes years ago (back in the valve days) the thing that made folks hair stand on end in those electrostatic demonstrations was Kilo-volts. In fact the current was in the Milli-amps. See I don't even remember how to spell it anymore.
But, I found the ultimate GrassMaster... this is what we need!
http://www.youtube.com/watch?v=Bc78DyVdbys&feature=fvwrel
But seriously, there is a fellow that builds a grass maker and offers kits, it is reported to have a lot more "poop" (a technical term similar to Volt-amperes) than what we are discussing here.
The big deal is he has Etch-it yourself PC board kits, pre-etched, parts kits, the works and so on that will save a lot of money... I have an email in to him asking him to describe his product so that we all can understand his product better. Here is his site...
http://www.ossynths.nl/grass-maker-and-more
Ken |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/25/2012 : 08:32:09 AM
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Thanks Mark
Do you have a picture of your unit , modified?
Mike M |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/25/2012 : 7:02:01 PM
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Hi All
so I just checked voltage on this thing. 1290 + - 10 volts DC.
That should be enough to stand things up.
I just watched a guy demonstrate making Tufts on U-tube. He used a metal plate as the ground and used decal paper to make his tufts with white glue.
Mike M
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/25/2012 : 7:30:46 PM
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At 55 yrs old, I've found I sometimes don't give things time to work. No Patience anymore.
Marks observation about not sticking up bugged me so I was determined to get it right.
So what I have found is that the "system" needs to build up a charge. 5 seconds is barely enough time. Now 10 seconds produces this result with 6mm grass. Hovering 1/2" from the surface and slowly raising the sifter helped to raise the grass.
I think it did a good job of bringing them soldiers to attention.
I found that the fall off grass fibers did not do well second time around. They did not take a charge well and mostly lay flat.
Mike M |
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jschumaker
Crew Chief
USA
853 Posts |
Posted - 06/25/2012 : 7:58:32 PM
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Has anybody checked out the static grass device articles in the online magazine, Model Railroad Hobbyist?
Jeff S |
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Mark R.
Engine Wiper
Canada
247 Posts |
Posted - 06/25/2012 : 9:50:26 PM
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That looks better Mike ! It's that resistor that is probably slowing down the capacitor's recharge time.
This is what my completed version looks like ....
Mark. |
Roach Custom Painting |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/26/2012 : 08:10:03 AM
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Hi Jeff & Mark
Mark, I saw another article last night describing the resistor removal as you suggested. I'm going to try that later this week.
I have 2 years of PDFs sitting on my computer as well as on a DVD. I need to go back and read them. It's one of the Best Model Railroad magazines out there and it's free!
Mike M |
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jschumaker
Crew Chief
USA
853 Posts |
Posted - 06/26/2012 : 2:12:08 PM
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Mike,
MRH issues Mar-Apr 2010 and Sept 2011.
Jeff S. |
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closetguy
Fireman
USA
1294 Posts |
Posted - 06/26/2012 : 9:15:49 PM
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| Thank you Jeff |
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Topic |
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Another Static Grass Apllicator
