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

[ducatiz]

Thanks!  What do you mean by "lance"?

medical term.  "stick a sharp object into a pimple or boil to release the fluid therein."

you can either cut away the surface or just make an X in the surface.  the point is to open it up enough so the coating goes INSIDE the void. 

if you have any fluid trapped as DucNaked did, you'll need to make sure to get all of them and then let the tank dry if you want to coat it.

i would probably not coat a tank that had trapped water like that though.  if you miss any, then you've got water trapped under the coating with nowhere to go.  if it ever escapes, then it will cause the coating to release.

if you cut open a few and they're all dry, you're probably safe.

i did my tank and popped all the zits with an exacto knife and a mirror.  none had fluid.

[Betlog]

medical term.  "stick a sharp object into a pimple or boil to release the fluid therein."

you can either cut away the surface or just make an X in the surface.  the point is to open it up enough so the coating goes INSIDE the void. 

if you have any fluid trapped as DucNaked did, you'll need to make sure to get all of them and then let the tank dry if you want to coat it.

i would probably not coat a tank that had trapped water like that though.  if you miss any, then you've got water trapped under the coating with nowhere to go.  if it ever escapes, then it will cause the coating to release.

if you cut open a few and they're all dry, you're probably safe.

i did my tank and popped all the zits with an exacto knife and a mirror.  none had fluid.

Gotcha.  I was rinsing the tank the other day with Acetone and it got pretty messy (spilled fluid all over the place and over the tank).  Any suggestions on how to seal the filler hole and the filter hole?  I'm thinking of just leaving the fuel tank door and fuel filter on there and rinsing it that way.  Would Acetone damage the filter components?  Thanks.

[ducatiz]

acetone will damage the paint, but not the pump/etc.

i used a #9 stopper and put it in from the inside.  If you pump iron and have 30" arms you won't be able to do this.

there is a small drain hole next to the filler, I just stuffed some wadded saran wrap in that. 

i used painters blue tape to cover the tank, but there are plenty of options.  I have another tank I might try coating for another bike and I think i'll use mover's cello-wrap instead and use the tape for the openings.

for the bottom, i cut a piece of 1/8" lucite plastic and made a cork O ring for the seal.  I cut a 1.5" hole in the bottom to pour in the coating and another #9 stopper for the hole.  It's a bit anal but it works well.

How you stop up the holes isn't as important as how you prep the tank and how well you cover the outside to keep the adhesive coating off it.

Whatever you think you'll need time-wise to dry the tank, just be patient and err going long.  It's really dry around here right now, ambient humidity is ~30% which is pretty low for here.  with that and a fan blowing into the tank, you can expect it to dry out after a few weeks.  The best way is to measure the bumper mount holes compared to a virgin plastic tank, i don't remember the width offhand (312mm?  330mm??)  but it should be the same fora virgin plastic tank as for a metal tank, but don't quote me.

That measurement is probably the most susceptible to expansion.

[Betlog]

acetone will damage the paint, but not the pump/etc.

i used a #9 stopper and put it in from the inside.  If you pump iron and have 30" arms you won't be able to do this.

there is a small drain hole next to the filler, I just stuffed some wadded saran wrap in that.  

i used painters blue tape to cover the tank, but there are plenty of options.  I have another tank I might try coating for another bike and I think i'll use mover's cello-wrap instead and use the tape for the openings.

for the bottom, i cut a piece of 1/8" lucite plastic and made a cork O ring for the seal.  I cut a 1.5" hole in the bottom to pour in the coating and another #9 stopper for the hole.  It's a bit anal but it works well.

How you stop up the holes isn't as important as how you prep the tank and how well you cover the outside to keep the adhesive coating off it.

Whatever you think you'll need time-wise to dry the tank, just be patient and err going long.  It's really dry around here right now, ambient humidity is ~30% which is pretty low for here.  with that and a fan blowing into the tank, you can expect it to dry out after a few weeks.  The best way is to measure the bumper mount holes compared to a virgin plastic tank, i don't remember the width offhand (312mm?  330mm??)  but it should be the same fora virgin plastic tank as for a metal tank, but don't quote me.

That measurement is probably the most susceptible to expansion.

Very detailed a always. Thank you. I see a bit of a mark on my paint but not sure if it's the acetone that I spilled or if it was from manufacturing.  I see Caswell also mentioned lacquer thinner as an option for rinsing. Would that be ok to use on the fuel system (filter, electronics, tubes, etc)?

[ducatiz]

Very detailed a always. Thank you. I see a bit of a mark on my paint but not sure if it's the acetone that I spilled or if it was from manufacturing.  I see Caswell also mentioned lacquer thinner as an option for rinsing. Would that be ok to use on the fuel system (filter, electronics, tubes, etc)?

wait, you're not leaving the fuel pump in the tank while doing this are you???

big no no!!

[Betlog]

wait, you're not leaving the fuel pump in the tank while doing this are you???

big no no!!

I did not but was wondering if I can.   

[jgrm1]

There is some great information here:  http://www.ducatimonsterforum.org/index.php?topic=54297.45

-Jeff

[Betlog]

There is some great information here:  http://www.ducatimonsterforum.org/index.php?topic=54297.45

-Jeff

Thanks Jeff.  I noticed that you used the screws to roughen up the inside of the tank.  Is this necessary?  Ducatiz, did you do this as well?

[ducatiz]

Thanks Jeff.  I noticed that you used the screws to roughen up the inside of the tank.  Is this necessary?  Ducatiz, did you do this as well?

its a good idea but im afraid of losing a few nails.  maybe try a steel detail brush or on of those ball shaped ones? 

[Betlog]

its a good idea but im afraid of losing a few nails.  maybe try a steel detail brush or on of those ball shaped ones? 

So you didnt do it on yours?

[ducatiz]

So you didnt do it on yours?

No.  I wasn't sure about it at the time, and didn't have any authoritative input on it.  I have spoken with adhesives people who know better than I do and they've all said that scuffing the nylon surface will help adhesion, but likely won't make or break it.

My tank had had less than half a tank of gas in it for less than a month when I drained it and flushed it.  I used the Marine Clean flush (water based solvent) and then water, water water, and then left it to dry with a fan blowing into the fuel pump hole (after hand wiping the inside with paper towels to get as much as possible).

By the time it was done after about a month of that, there wasn't even a faint smell of gasoline, just plastic.

I picked up a fibre optic camera and I may take the tank off when it gets cold and see how the coating looks.  I have a feeling it will be fine.  The exposed part under the filler is fine.

[AMGnDuc]

Thanks Jeff.  I noticed that you used the screws to roughen up the inside of the tank.  Is this necessary?  Ducatiz, did you do this as well?

I threw about 50 screws in the tank to scuff up the sides but I don't really think it did all that much.  It left some fine scratches but hardly gouged the surface much.  As stated above, I don't think it makes or breaks the process.

Just make sure to count them out thoroughly before you throw them in!

[ducatiz]

I threw about 50 screws in the tank to scuff up the sides but I don't really think it did all that much.  It left some fine scratches but hardly gouged the surface much.  As stated above, I don't think it makes or breaks the process.

Just make sure to count them out thoroughly before you throw them in!

the hypothesis is that the rough spots give the epoxy something to "hang" to.  not that they will break the surface completely.

[jgrm1]

Thanks Jeff.  I noticed that you used the screws to roughen up the inside of the tank.  Is this necessary?  Ducatiz, did you do this as well?

Trying to dig those last seven screws out of the tank probably did more to scratch up the surface than the screws themselves.  By the way, I could not reach into the tank to lance more than a couple blisters, so I gave them the sign of the cross an buried them under a layer of Caswell's.  Ya do whatcha can.

-Jeff

[Ducatamount]

http://www.accessnorton.com/ethonal-proof-tank-sealer-myth-t13056.html
 Some good info and links here.