Author Topic: Tank refurb - using sealant remover - protecting paintwork.  (Read 468 times)

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hoogerbooger

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I have all the chemicals and I'll probably do the prep and seal next weekend. I'm using Sealeater (di-chloromethane) stripper

Any more advice on minimising the risk to the external paintwork would be appreciated.

I was previously advised to wrap the tank in cling film to protect the paintwork. Will that survive Di-Chlorometane ?

( Presumably I should remove badges and rubbers to be on the safe side)

Also wondering what's best to seal the tank filler ?  In video of people using the de-greaser and metal prep after the sealant removal  they've used duct tape to seal the tank filler. Would this also be ok for the stripper ? I'm not sure whether it may get 'eaten' or not stay watertight.... particularly as gravel should be added for that stage)

Or for the stripper stage should I use the chrome tank cap ?

The tank will need to be emptied. I'm presuming using the fuel tap opening into a bucket.. Looks to me that some extra protection to the paintwork around the fuel tap opening may be needed ?

.....and then the tank will need rinsed .

advice much appreciated


DEAN SOUTHALL

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #1 on: 07 May, 2018, 20:10:31 »
I used the cling film approach with duct tape over the filler hole and tap hole bungs made with bolts wrpped with insulation tape.
You shuold not need to shake the tank with the stripper in: the solution and its fumes will get off the old sealant.
You probably won't have to worry abotu pouring out the used sealant as there might not be any left.....I found it evaporated as fast as anythig. Hence the need to do this outdoors..you don't want to be breathing those fumes.

hoogerbooger

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #2 on: 07 May, 2018, 21:15:26 »
Thanks Dean

insulation tape ? as in electrical insulation tape ?

( instructions say need to put a handful of gravel in to aid process hence my comment on shaking .. having said that I've done half an hour of shaking  with nuts n bolts in already, to scour off loose stuff)


hoogerbooger

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just used the stripper (Sealeater).  Duct tape didn't seal fully even with a patch of a couple of laminated  layers zip tied onto the filler.   So I suspect I will have some damaged paint when the cling film comes off

I have re-bottled the stripper.  I only had it in for an hour. swilled around all areas and then left it in differing position for 5 mins in between swills.  It's evaporated off inside now. can't see any peely  liner bits .... but then wasn't sure there was a liner. Was some white and blue paint ( presumably from the tank spraying) on the flat horizontal section below the filler and I can see this hasn't completely lifted. This seems to be the harder bit to swill as with one litre of stripper it won''t cover it.......and the filler was leaking hence I stopped.

1. would using the chrome tap be more likely to seal ? Any advice ?
as I'll need a better seal to swill the 0.66 litres I have left onto that section



Also ..If it's only local damage around the filler and petrol tap, I'm hoping to do a temporary touch up....as I need to see if I can get it on the road in the next couple of weeks. Been looking for advice on the web and only seem to find full re-spray or small chip repair.

2. Anyone able to advise on something in between/ provide a good link ?

I can get the right paint/spray.  Was thinking remove any bubbled paint. sand to a tapered edge. Light sand a larger area around to provide a key on the good paint.  Cover protect  the parts not to paint. spray prime bare metal and an over-lap of part of the keyed area. then lightly de-nib if needed, then a few light coats of spray top coat.

Does that sound right ?

(I'd plug the holes so spray stays out of the tank).







« Last Edit: 14 May, 2018, 15:38:02 by hoogerbooger »

AWJDThumper

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #4 on: 14 May, 2018, 16:32:59 »
It's best to use a proper tank cap to seal the tank although you need to block the small vent hole to prevent leakage there.

In terms of repairing any damaged paint, it depends on how good a job you want to make of it. In general, you need to use filler to bring any areas stripped back to bare metal up to the level of the surrounding paint work. The best way to apply primer, base coat or clear coat is with an air brush if the area to be covered is relatively small - I've used a 15 air brush with propellant can from a model shop to do this type of repair in the past and achieved very good results. Using an aerosol or full sized spray gun to do this type of paint repair is very difficult because the spray pattern will be too large as will be the flow rate.

hoogerbooger

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #5 on: 21 May, 2018, 23:43:14 »
Degreased and used metal prep ( phosphoric acid) this afternoon. Duct tape proved rubbish again in sealing at the fuel filler. Ended up using the filler cap with thin polythene and a cardboard seal ( to replace the rubber seal the paint stripper ate) This worked pretty well, but still leaked a bit when upside down. Electricians tape also seems to work well to protect paint around fuel tap hole.

(On reflection I'd recommend using the fuel cap for all stages bar the actual sealer. But practice getting a good seal with water in the tank first).

Removed the cling film and have dried the inside with vacuum sucking through & hot air gun on the outside (with care). That worked well. helped by a warm afternoon.

I do have some new paint damage around the filler cap, with a run that went from the cap along one of the top joints with the paint there now cracked and damaged most of the length.

However the paint wasn't good before with dimples ( I presume rust from underneath) plus various small chips and a big one around the centre bung.

Photos of damage attached.  What causes the dimples/rusting from underneith ?? need to avoid that happening again so what did the last person do wrong ?

I reckon the tank needs a complete respray really, but I'd prefer to do that later and first try to get the bike going and MOT'd. So thinking of doing very little now apart from clean up around the inside of the filler and apply the sealant.

If I do the respray later, roughly how long will I need to have it off the bike to let the petrol evaporate off before sanding down and spraying ?



AWJDThumper

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #6 on: 22 May, 2018, 07:52:31 »
I can see the rust bubbling up under areas of the paint and so a complete repair is probably the only long term solution. Now that you've cleaned out the inside of the tank, there's not going to be any petrol to worry about in terms of painting the tank.

Mike Farmer

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #7 on: 22 May, 2018, 09:48:47 »
 :)

To seal the filler opening.  Cut a piece of old inner tube or similar--side of an old rubber boot will do. Put it over and around the filler and hold tightly in place with a jubilee clip. Double layer to be on the safe side if you wish.

Luck 

Mike 8) 8)
« Last Edit: 22 May, 2018, 20:44:54 by DEE »

hoogerbooger

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #8 on: 22 May, 2018, 20:56:08 »
sorry wasn't clear. Was thinking of getting it on the road this summer with the paint as is . Then coming back to a complete tank repainting in the autumn/next spring.

most of the rust dimples have no sign of any crack in the paint/air source from the outside...so wondering what the likely cause(s) might be..... so anyone know.
 

AWJDThumper

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Re: Tank refurb - using sealant remover - protecting paintwork.
« Reply #9 on: 22 May, 2018, 22:45:57 »
If all the dimples are due to rust bubbling up under the surface then it probably simply down to a very poor paint job with the surface not properly prepared beforehand. I've come across a lot of examples where people have painted over a very thin layer of rusting without getting rid of it first. Years later, the rusting will break through to the surface.