Yet Another Cycling Forum

General Category => The Knowledge => Topic started by: Junglist on 31 August, 2019, 08:15:42 pm

Title: Retouching frame finish
Post by: Junglist on 31 August, 2019, 08:15:42 pm
I have damaged the finish on my frame by using an ill-fitting BB tool. There are 3 areas on the bottom bracket shell, 2 underneath and 1 on top. The finish is a textured matt black anodising on a 7005 T6 alloy frame. I have rubbed down the areas ready for painting as shown in the photos.

(https://i.ibb.co/vBCVvrB/DSCN2126-A.jpg) (https://ibb.co/mBrbFYB)

(https://i.ibb.co/Yypwdwm/DSCN2127-B.jpg) (https://ibb.co/Hxn3P36)

My research has suggested I need an etching primer, although I don’t know what effect it may have on the surrounding anodising. I had hoped to use a brush rather than spray but this I understand is not advised as you need a thin layer which is difficult to control with a brush.

As for the top coat, I’m not sure if matte or satin will be the better match and there’s so many different types of paint I don’t know where to start. I’m not expecting a professional finish, just a hard wearing one.

I also need advice on masking tape as I don’t want paint on the face of the BB shell.

Thanks, Mark
Title: Re: Retouching frame finish
Post by: Bolt on 01 September, 2019, 04:45:48 pm
Given that the paint damage is mostly out of sight I'd be more focused on protecting the frame than trying to obtain a perfect finish. To that end I've had good results from this paint that can be applied directly to pretty much any surface including aluminium.(https://uploads.tapatalk-cdn.com/20190901/5451fbfa30265f7d6548ed10c9bb9e75.jpg)
Title: Re: Retouching frame finish
Post by: The French Tandem on 01 September, 2019, 05:00:54 pm
Automotive touch up pens? £5.49 in your nearest Halfords.
 
Title: Re: Retouching frame finish
Post by: drossall on 01 September, 2019, 07:44:24 pm
That's what I often use, and of course there is a wide choice of blacks.
Title: Re: Retouching frame finish
Post by: Junglist on 03 September, 2019, 04:15:49 pm
Thanks for the replies. I'll check out that paint. :thumbsup:
Title: Re: Retouching frame finish
Post by: phantasmagoriana on 03 September, 2019, 07:11:26 pm
I normally just use nail polish! ;D
Title: Re: Retouching frame finish
Post by: Blodwyn Pig on 04 September, 2019, 07:20:19 am
I normally just use nail polish! ;D
^^^ whs. Clear, if needs be.
Title: Re: Retouching frame finish
Post by: rogerzilla on 04 September, 2019, 08:55:56 pm
That's what I often use, and of course there is a wide choice of blacks.
I found one that's an almost perfect match for Moulton ivory powdercoat.  I need to touch up an old Hobbs frame and may take the fork into the shop to try and find a decent match.
Title: Re: Retouching frame finish
Post by: trekker12 on 05 September, 2019, 09:11:24 am
As a model aeroplane maker I have stocks of Humbrol enamel paint which does touch up work fine, readily available in hobbycraft etc and I mix to get as close a colour match as I can. The model makers masking tape they sell in there is good quality too.
Title: Re: Retouching frame finish
Post by: mrcharly-YHT on 05 September, 2019, 09:24:50 am
I normally just use nail polish! ;D

This, but matt would be difficult to achieve. Is there such a thing as matt nail varnish?

Clear will protect the frame.
Title: Re: Retouching frame finish
Post by: phantasmagoriana on 07 September, 2019, 02:03:36 pm
I normally just use nail polish! ;D

This, but matt would be difficult to achieve. Is there such a thing as matt nail varnish?


There is indeed! I've got some matt black stuff for one of my bikes.
Title: Re: Retouching frame finish
Post by: drossall on 07 September, 2019, 11:53:03 pm
I got matt black touch-up paint from Halfords for my Brompton.