Scale Soaring UK

Hope this is the right place for this.

I am doing some work to finish a 1/4 scale Ka6e.
I can mask up the white gelcoat areas which I don't want to have to paint.
But how do I rub down with wet and dry abrasive paper right up to the edge, without damaging the masking tape edge, so when the paint goes on the white gelcoate edge is crisp and straight to the painted edge where it was keyed up to??

If I have to mask, key, re-mask there is no guarantee of getting the edge exactly in the right place.

John M

John, this works for me . The area to be protected from sanding I cover with electrical insulating tape. You get a sharp line to work to and it takes quite abit of scuffing without damage . Then take the tape off and run masking tape on the shiny line. Regards John.

Thank you John, but I still have two applications of tape and not 100% sure I can accurately match up the second application to the line.
But as you are the only one to give any advice from 59 people reading it, I will give it a try.
Like the elect tape first idea though.
Cheers John M

Hi John,didnt see your post till now sorry.
There is on the market a pen that is made to abrade miniture circuit boards before soldering. They are only a few shillings and very handy for many things including the area of which you need. The amount of abrasion required is made by turning the pen nib much in the same way as lengthening the lead in a propeling pencil.You can use it right up to the tape without damaging the tape. Can be obtained from good electronic retailers.If you are completly stuck in these unusual times I could send you one of my spares. Regards.

Good idea Terry.
They are called fibreglass pencils - Just do a google search.

Thanks Terry, I'll check out where to get one or two, as that seems to be a good idea/technique.

John M

Available in a few days on Fleabay from various sellers, including this one (set of 3 for £2.79 post free!)
https://www.ebay.co.uk/i/183935189697?c ... gKvIvD_BwE

Hi,That's the ones Peter. the fiber glass pens are plenty abrasive enough for keying in the paintwork to glass fiber as John is intending to do. The brass and steel pens are ideal for making a deeper key onto glass fiber when bonding things to it.I.E. inside the fuselage to install former's and wing joiner tubes. Etc. Don't forget the mask and goggles guys the dust produced is very fine.

Regards Terry.

My original post on this subject covers the safety aspect of that dust as the method described is done with wet and dry abrasion as the electric tape is impervious to the water. All my glass work is done with wet and dry and in my opinion is much safer. Regards John.

Going slightly off subject, but related, I have just hand painted a fibreglass fuselage using a 2 pack paint from International in their Perfection range. It is the best paint I have ever used bar none, goes on nicely from the brush and immediately the brush marks flow together and leaves an incredible glass like surface you can see your face in. The downside is the expense, about £35, but if you are spending a fortune on your glider this has got to be a bearable expense.

https://www.international-yachtpaint.co ... perfection

Seems to be £57 for 750ml at my local stockist!!

A method I have used with good results is to flatten off the surface that you are painting as close to the masking tape as possible. Then use a product called "Primol", it is a rather smelly product that you wipe on the surface with a cloth. This etches most surfaces and helps adhesion of paint.

Thanks for all the replies and suggestions chaps, much appreciated.
I have now received the "set of pens" in brass, steel and fibreglass from the net, so will be going down that route to key up to the tape edge.
Hoping to maiden this one sometime this year.
Long Mynd is favourite,especially as the Sherlowe and Milson aerotow's may, or may not happen.

John M

Vince, having just spent £100 on rattle cans of 2K that might not be sufficient, I am intrigued by your paint suggestion.

Did you undercoat first or just abrade? I've just used a replacement for Japlac on my tug and it isn't a patch on it - I did some research and it seems international went bump, so presumably AkzoNobel bought the trademark?

Anyway, be very interested to hear, especially with brush application as spraying is not the easiest thing for me to arrange logistically.

Cheers, Ell.

I lightly abraded the fuselage and the paint seems to have adhered well