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12 posts • Page 1 of 1
I've recently decided to try and build up a bike from scratch, with the idea being it'll be a good way to get my head around how a bike works in it's totality.
So, I bought a frame off this forum and am currently in the process of painting it up with spray cans.
I (perhaps foolishly) decided to try and go for a two-tone colour scheme with a black base and a white head tube and strip on the seat tube.
I did this by painting the white sections first, waiting a few days, then masking them off and doing the rest of the frame in black.
Now I've peeled the masking tape off it seems as though the tape has left an imprint in the white paint. Although it could be left over residue, but I'm not entirely sure.
Has anyone encountered this problem at all?
And any ideas of how to remedy it?
Was planning on sanding it back a bit and putting a clear coat over the top, but thought I'd seek the wisdom of the forum beforehand incase I'm missing anything.
If you left the paint to dry for a couple of days before masking then I would assume it is residue, though how long did you leave the masking tape on the frame and was it cheap $2 shop tape?
Depending on how you prepped the frame, is it possible you have sprayed Acrylic paint over an existing Enamel paint? This will cause a pealing effect to happen, and possibly the paint to flake off with the right paint quantities.
I would need a better description of what the effect looks like, or some close-up photos of it though before it is anything more than a guess.
Acrylic paint stays soft.
Masking over soft paint wil mean you wil make an imprint in the paint.
Thats the downside of using spraycans.
You can try sanding but be carefull as the layers are thin.
And you can easily rub trough.
The only tip i can give is next time don't apply much pressure to the tape .
Other then that you can't do much to prevent it as the paint stays soft and wil be prone to imprints.
The dutch have one word to describe the aussie MHL, this word is ;
The tape was "3M scotch blue painters tape for multi-surfaces". Cost about 10 bucks and was advertised for use on metal.
It got left on for about 2-3 days from memory.
The paint has a grain consistent with that of the tape as it was applied.
I didn't do the prepping of the frame. I bought it post-sandblasting and primer. None of the rest of the frame has this issue just the bits that I masked over.
I used enamel spray paint.
At the end of the day, I'm not too fazed by the imprints, wasn't expecting the bike to be a piece of art, just a fun project. Just wondering if there's anything I can do about it or whether it's not worth the effort?
White paint wasn't dry.
I tape-paint-remove in a single process where possible so tape is normally only on for a couple of hours at most. By removing the tape before the black has dried (and even still wet) will avoid the sharp "cliff" edge.
To fix you could wait until it is very dry and then hit it with some wet&dry and then lay some clear over it.
Paint scheme looks good mate. I'd put some WD40 on a rag and rub that over the white area, see if that gets it back to nice and shiny, never know, it might just be something left behind by the tape and WD40 is awesome at removing residues, just wash it off after you've used the WD40 on it.
I'd give it a wet rub with very fine sandpaper to give it that smooth finish (1,200 grit or finer). But some enamels don't really like sanding, see what it says on your can(?). If it does make it do something you weren't expecting, you can just paint again
Paint's one of those things, extra effort always leads to an awesome product let us know how you go.
That's a shame. How long do you usually wait to mask over paint?
That depends.. paint thickness is a biggie..
If its to thick i can take months to fully dry.
Also the blue painters tape was far from ideal as it designed to be used on unpainted surfaces.
To tape over a painted surface a tape made from vinyl would b better.
Vinyl is smooth...
Paint trying time is based on: i) thickness, ii) temperature, iii) humidity, iv) paint type.
I have a can of the cheap "Fiddly Bits" enamel paint that on cold days or high humidity days can still not be touch dry 24 hours later.
Depending on the spec's of the paint, but normally temps need to be high 20's and low humidity and paint will be touch dry within a couple of hours and in a pinch maskable next day (this is using automotive acrylic paint, machinery enamel I would give it at least 2 days but that stuff can still accept a thumb print for days later if layered on thick).
Also from the imprints it suggests that you may have put the tape on tight, which if was the case would avoid in the future. Just put it on lightly, makes it easier to get off.
Enamel also isn't the best paint for this type of application, it stays soft for a long time, and never really gets as hard as other options but does have reasonably good chip prevention as a result. Automotive acrylic would be the best solution for a DIY application.
But in light of all that, what you have achieve is very good. Considering that you only used a spray can and it is your first attempt, you should be very happy with the result. Done the hard way and a very acceptable result.
12 posts • Page 1 of 1
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