Plastic Tank problems: Discussion thread, see info thread sticky for updates

[myleslong]

Hello all,
As promised, I'm posting the results of my Caswell adventure.
 I can only report my opinion based on my experience. I did the Caswell treatment on my brand new tank last week.
I sent Caswell an E-mail explaining that my tank was new and had never had gas in it.
 They strongly recommended that I use the acetone and dry wall screws to rough up and soften the surface a little. Against my better judgment, I did, based on their strong recommendation.
Of the 10 drywall screws I put in, I was only able to get 6 out. As I was shaking the tank with the Acetone and screws, the rattle sound gradually disappeared all together.
No amount of shaking, tapping the inside of the tank with a rubber dead blow, or rotating the tank for at least 25 minutes would locate the remaining 4 screws. no rattle from the screws...nothing, Long flexible magnet no success.
 I finally gave up and they got "Caswelled" in place forever.
 As a bi-product of this exercise and despite much masking, taping, tin foiling etc.etc.  some of the acetone managed to get by the fuel fill plug and onto the stripe in front of the filler and immediately ate the clear coat and was working on the decal itself. I was not happy.
By the way..  doing a fingernail test of the inside of the tank at the fuel pump hole after the acetone disaster I noted absolutely no difference in the surface.
So..... New tank decal  $25.00.... Scuff and re-clear the tank about $150.00 and about 4 extra hours of my time.
 I did the coating in 2 stages..1/2 of the product and then 10 hours later the second 1/2. It seems to have covered well and is as hard as a rock. I strongly recommend thinning as much as the directions allow.
This stuff is as thick as honey and a pain in the ass to move around in the tank before it begins to kick  @76 deg.
 If I had it to do over, keeping in mind that my tank is brand new, I'd skip the acetone... Probably do water with at least 13mm nuts or bolts for the roughing up. The dry wall screws are way to skinny for a Monster tank. I guarantee it.
 I hope this is the final solution, cause it sure has not been a fun or rewarding exercise, and has ended up costing me a couple of hundred bucks and much aggravation.
 By the way, I've been a mechanic, working on on bikes, cars, painting, fabricating etc. for over 30 years, so I'm no rookie.
 Take my experience as a warning, the acetone is lethal to paint and clear coat. THE DRYWALL SCREWS ARE TOO SMALL...DON'T USE THEM !!
Good luck to all who decide on this option.
Regards,
Myles

[ducatiz]

I just don't get the drywall screw part.  It serves no purpose for a plastic walled tank.

[BoDiddley]

myleslong : Man sorry you had to learn the hard way and I am glad you informed us.  I think i will forgo the screws for sure and I think I will use a bodyshops gunwash solution.  It has acetone in it but no where near full strength.  I used to be a bodyman and you can usually use it on paint as long as you take it off right away. 

I am still curious about the "shrinking in time" affect that I have read about on other forums.  The more I read about it the more it seems viable to a point.  But even a little shrinkage would help most tanks.  I am going take a few precise measurment and put a fan blowing through it for a week.  I will post anything I find.  If it shrinks even 2% a week it would be worth it for the rest of the winter.  Then do the Caswell.

[jgrm1]

...acetone managed to get by the fuel fill plug and onto the stripe in front of the filler and immediately ate the clear coat and was working on the decal itself...

I have been trying to figure out how to swish with acetone without damaging the finish.

-Jeff

[sbrguy]

is there any way to make the caswell move more like water in the tank instead of honey? and will this then affect how well the stuff works?

also why did you use 1/2 and 1/2 would it be better to use the whole can or even 2 cans to do one tank the theory being more stuff to slosh around equals easier to coat everything in one shot or would that just make it too thick?

[ducpainter]

is there any way to make the caswell move more like water in the tank instead of honey? and will this then affect how well the stuff works?

also why did you use 1/2 and 1/2 would it be better to use the whole can or even 2 cans to do one tank the theory being more stuff to slosh around equals easier to coat everything in one shot or would that just make it too thick?

2 cans won't make it thicker, just more thick stuff in the tank at one time.

Over thinning would probably affect the cure in a detrimental manner

[sbrguy]

It has to be some legal reason.  My guess is that the US version has to be CARB (california) compliant.  It's a long explanation why we have two sets of emissions laws in the USA (Federal EPA and California ARB) but Cali is a huge market for bikes and no importer would ship bikes here without being Cali compliant.

That's why US bikes have the vapor emissions (charcoal) canister on them -- and the fuel tank must work with it.

Likewise, there may be some additional crash requirements which necessitate the nylon tank.  I know for a fact that all PE's (HDPE, XLPE) are less shatter resistant than nylon (which bounces).

...but this is all beer pub speculation.

ah ha, so now the key is how to get your hands on some xple tanks instead of the pa tanks.  that would probably solve everything..  anyone know someone in antoher country to ship them?

[sbrguy]

what is the acetone used for?

[BoDiddley]

what is the acetone used for?

Acetone is solvent to plastic because it is made from plastics, a good example is the primer that is used for PVC plumbing.  It softens and expands an outside layer of the plastic which makes it adhere well to other "hot" solvents, the glue.  So the tank needs the acetone to soften as well as clean I presume.  Someone that knows more than I about plastics can say more about that.  Being an ex NASA paint man I have used a lot of Acetone.  That is why it is eating the polyurethane base of the clear coat and anything else plastic.  

I am still waiting for my tank to dry and for the can of Caswell.  You do not have to leave the acetone in the tank longer than five seconds.  Just enough to cover and clean all of the inside surface and then drain it out fast.  So you have absorbant rags at the ready, you seal the main bottom plate hole "tight" with duck tape, have a rag made up to fit tight in the cap hole.  Outside over whatever you can use to catch it, have the tank in your hands with one over the bottom hole keeping pressure on the duck tape (using a thick rag to distribute the pressure), have a friend with a funnel, carefully without spilling a drop, dump in a quart of Acetone (or gunwash / lacquer thinner) stick the rag in the cap hole, shake it around good for 5 seconds, hold the tank over a large pan and have your buddy pull off the duck tape.  Clean quick with rags and continue on with the caswell as soon as you are done cleaning it.  I would even have the Caswell ready to go or at least ready to mix before the clean.  Make sure the acetone is completely dry.


Acetone will eat up any rubber gloves that you find at the grocery store but they should give you time to keep it off your hands, just peel them off ASAP.   Or buy a couple pair of solvent resistaint gloves from a manfacturers supply shop.

I am going to use gunwash as I mentioned before instead of acetone, you can buy it at any parts store that carries automotive paints.

I am wondering if the Caswell is a solvent, it would be good if it is but if it is a two part system it probably is not.

Good Luck!

[ducatiz]

is there any way to make the caswell move more like water in the tank instead of honey? and will this then affect how well the stuff works?

also why did you use 1/2 and 1/2 would it be better to use the whole can or even 2 cans to do one tank the theory being more stuff to slosh around equals easier to coat everything in one shot or would that just make it too thick?

Double check with Caswell, but thinning with MEK should be fine.

2 cans won't make it thicker, just more thick stuff in the tank at one time.

Over thinning would probably affect the cure in a detrimental manner

MEK is volatile, it just poofs out with good ventilation.  I used it with the Bill Hirsch coating which is also a 2-part setup and smells the same.  (which is how I identify chemicals, just like a Bloodhound)

The best way to do it is to keep the ingredients at room temp or above, around 70-75 F.  If you thin, then go very conservatively and use no more than 2-3 drops at a time. 

[BoDiddley]

Double check with Caswell, but thinning with MEK should be fine.

MEK is volatile, it just poofs out with good ventilation.  I used it with the Bill Hirsch coating which is also a 2-part setup and smells the same.  (which is how I identify chemicals, just like a Bloodhound)

The best way to do it is to keep the ingredients at room temp or above, around 70-75 F.  If you thin, then go very conservatively and use no more than 2-3 drops at a time. 

Ducatiz : Do you have confidence in Bill Hirsch's coating adhereing to the inside, if you can delute it with mek then itself must be a solvent which is good?  Just when a person has a fix more information comes along everytime.  The gods of the forum must be laughing

[ducatiz]

Ducatiz : Do you have confidence in Bill Hirsch's coating adhereing to the inside, if you can delute it with mek then itself must be a solvent which is good?  Just when a person has a fix more information comes along everytime.  The gods of the forum must be laughing

I have NO EXPERIENCE with the Bill Hirsch coating on the Ducati NYLON tank.

I have experience with it on METAL tanks.  I have never contacted Bill Hirsch to see if they think it will adhere to plastic/nylon. 

I have used it on 5 metal tanks and diluted it a good bit -- it rolled thru the tank pretty quickly, and just kept the air moving.  It started to thicken after about 20 minutes of turning the tank and covered everything enough after about 30 minutes and stuck. 

[Heath]

<snip>
 If I had it to do over, keeping in mind that my tank is brand new, I'd skip the acetone... Probably do water with at least 13mm nuts or bolts for the roughing up. The dry wall screws are way to skinny for a Monster tank. I guarantee it.
<snip>

Why would you use water when that is what is making the tanks expand? 

[ducatiz]

Why would you use water when that is what is making the tanks expand? 

A few seconds of contact probably won't hurt it, the problem is constant contact.

[BoDiddley]

I have been drying out my tank since Saturday morning, 48 hours.  I took some fairly precise measurements before I started.  I took a measurement this morning and was thrilled to see that the width had come back 1/16th of an inch.  But the length did not, which I thought would have the most shrinkage.  !!IT SHRINKS BACK!!  Time will tell how much but it is good news to me to see it actually get smaller by even that little bit.  I am going to leave it blowing for at least a month before I coat with the Caswell (michigan winter).  If nothing else you do not want it shrinking or moving at all with a coating on the interior.