Sealing Baits with Dissolved Plastic Cups

[.dsaavedra.]

i remember a while ago seeing a tutorial (the name Sally comes to mind) about dissolving plastic cups in laquer thinner and then dipping your baits in it to seal them for testing.

i tried this with Sunnyside laquer thinner, and i couldn't get the cups to dissolve. i was using the larger red/white solo cups. they just got thin and mushy. i can get styrofoam to dissolve real easy though.

so, two questions:

1. is there a trick to getting cups to dissolve?

2. could i use styrofoam and get good resluts?

[jrhopkins]

i tried the Solo cups too with the same results. i use the cheapest clear plastic cup Walmart sells in acetone, works fine. start out with a thin solution and then add cups as needed.

[atrophius]

I am pretty sure you have to have the right plastic. I have not done it myself, but I have read up on it. The things I read about used acetone and certain plastics. Not sure if laquer thinner is the same as acetone. You can check the numbers on the bottom of the plastic to see what type of plastic it is. Hope that helps ya some. Maybe someone else can chime in here.

If you are going to use plastic cups though, you might just be better off buying some of the propionate on ebay. There is a member here that sells it so do a forum search on propionate. It will save ya some hassle most likely with finding and mixing plastics in your solvent.

Ah good Jr wrote the same time I did. he knows better then I for sure.

Edited May 3, 2009 by atrophius

[Lincoya]

If you are going to use lacquer thinner, then it must be virgin lacquer thinner (no pun intended here). You can find it at automotive parts places like Autozone for about $10 a quart.

Gene

[BobP]

There is no official formula for "lacquer thinner". The solvent mix listed on the LT sold in home centers changes depending on what solvents the manufacturer wants to use. "Virgin lacquer thinner" sold in most automotive stores is usually more reliable. Acetone dissolves plastics more quickly. How a particular plastic cup + a particular solvent will perform on a crankbait can only be discovered with experimentation. Some guys report poor adhesion and/or cracks in the coating after a while. Some like it fine.

[.dsaavedra.]

ok thanks guys. i might have to try acetone. and some real cheap plastic cups. i'll also go read that tutorial again and see what it has to say.

guess i gotta read up more on my organic solvents.

[Wayupnorth36]

I experimented with this a while back, and did a lot of reading. Those recycling numbers are the key to which kind of cup to use and what to use to dissolve them. Here is a link to a web page that explains the recycling numbers...

PLASTIC RECYCLING NUMBERS

Here is a link to a page I found listing all sorts of plastic and their resistance levels to different chemicals, including all of the common solvents, acetone, toluene, mineral spirits, etc..

http://www.labcon.com/Media/crchart.pdf

This oughta speed up your experiments a bit.

Alex

[atrophius]

I have a question about this. I am using acetone and used #6 cups. According to the recycle number, it should dissolve. Problem is, it has been a pile of goop at the bottom of the jar for 3 days now. Any idea on why this is not dissolving? #6 is polystyrene btw, which should literally melt in acetone.

[mark poulson]

Try acetone and the salsa cups you get at fast food restaurants.

I mix my paints and epoxy in them, and made the mistake of putting some acetone in one. When I picked it up, the bottom was missing.

[robalo01]

I used acetone and salsa cups and got the same gue. What is it supposed to look like?

[mark poulson]

robalo01,

I guess the fool proof thing to do is to use Propionate.

Someone on this site sells it.

[mark poulson]

Do a search here for propionate.

Palmetto Bass sells it, in the classifieds.

[whittler]

By the time you buy cups and twice the amount of acetone or virgin LC, gone through enough of both to trying figure out the correct mix you will wish you had just gone to PalmettoBass, got the right stuff, followed his directions and been done with it. Do it right, do it once.

Nothing is foolproof, "Fools are ingenious"

[atrophius]

Ok, you got a point. Is there a way to dispose of acetone correctly?

[mark poulson]

If it's still clear, with just a lump of goop in the bottom of the jar from undisolved plastic cups, I'd decant it by pouring it off slowly without letting the goop get mixed up in it, so all I had was the clear acetone. Then I'd try it with the propionate and see if it works. Even though it may have some plastic disolved in it, it's probably the same plastic that's in propionate, or something similar, and shouldn't mess up the final sealer. I'd do a test with a small amount of the tainted acetone and a few propionate pellets, and see if it works.

Otherwise, if it's discolored and can't be reused, it's considered a hazardous material, like oil based paints, and you'll have to check with your local govt., maybe your fire dept., to find out how to dispose of it.

You might also ask a local paint store.

[.dsaavedra.]

By the time you buy cups and twice the amount of acetone or virgin LC, gone through enough of both to trying figure out the correct mix you will wish you had just gone to PalmettoBass, got the right stuff, followed his directions and been done with it. Do it right, do it once.

Nothing is foolproof, "Fools are ingenious"

all i have bought is acetone...money not wasted...i'm going to need it for propionate anyway.

i will look into propionate, how expensive is it? also, the pellets palmetto is selling are blue? does this make your sealent blue?

[Vodkaman]

The blue tint disappears once the pellets have dissolved.

Using the prop as a sealer, the color is not a factor.

Dave

[RiverMan]

I tried the plastic cup sealer a couple years back and personally don't feel it is worth the hassle. If water gets past your outside clearcoat you are probably doomed so why bother with the plastic cups?

I would suggest you use two coats of sanding sealer then a good white primer. If you want something better than sanding sealer, use a coat of etex as your sealer, then prime, paint, then another coat of etex.

Jed V.

[philB]

Not all plastics are the same and that goes for cups as well. Use proprionate with virgin thinners (cellulose thinners here in the UK) as it evaporates at a slower rate, acetate flashes off in no time but leaves a blush but that isn't a big deal when used only as a sealer.

[.dsaavedra.]

what is sanding sealer?

[jameso321]

I use prop. for testing. It is the best thing in the whole world for getting a test bait in to the water in a few hours from square block of wood. Some guys use it for sealing all the time. I use epoxy for sealing when I make a bait from start to finish.

propionate

I bought mine from dude on ebay and I bought a small amount from "swede"