I have finished a mosaic on a round piece of jigsaw cut and sanded ply/weatherboard (35 cm dia), which I had sealed all over with waterproof PVA - (now don't shout at me Dave, that was before I read your stern words of wisdom )

Now I would like to give the cut edge a nicely rounded smooth finish, probably most suitably carried out with all purpose polyfilla (any other ideas, go right ahead!), and then undercoat and gloss or enamel paint that edge (as well as the back) in white, to make it really weatherproof and to visually blend in with the white grout (Ultra) I'll be using, so basically it'll look pleasingly finished from all sides. It is meant for my parents' old peoples' flat balcony wall, and will live there come rain or shine....

The question is, at the points where white grout (Ultra) and polyfiller meet, will they connect happily or separate from each other? Would be a shame to have hairline cracks. I can do the glossing last, right up to where the grout will be...

have you considered decorators caulk? it is flexible, waterproof and paintable when dry.

Originally Posted by grumpygrouter

have you considered decorators caulk? it is flexible, waterproof and paintable when dry.

No, have heard of it, but don't really know what it is - and could I get it in B&Q?

Originally Posted by Mosaic Girl

No, have heard of it, but don't really know what it is - and could I get it in B&Q?

If you must but Screwfix do good deals

a bit of crazing mosaic girl, you could pass it off as delft ware,(got an "A"level in pottery)

I did some plant pots for home using glass mosaics (on old chimney liners) I used ultra flexible grout, they've been outside 4 years and still stable

Originally Posted by doug boardley

I did some plant pots for home using glass mosaics (on old chimney liners) I used ultra flexible grout, they've been outside 4 years and still stable

yes, I know the ultra will be fine, just not how it will meet/combine with the polyfilla or now maybe caulk...the shaping of the edge is more of an issue than the grout...bit preoccupied here, as I am alternating looking at the screen with crawling about on the floor trying to catch the mouse the cat brought in, now looking at us from under the cupboard, not knowing that the cutest cat in the universe won't kill it but hand it to me as a present, fully alive and intact, and then I give it a hospital recovery stay in a glass jar complete with dried grass and bird seed before letting it off again on the clifftops behind our house ...when the cat isn't looking...now that is what \I cann an exciting life on a Friday night...now back to playing Dr Dolittle...byeeeeeeeeee

trying to visualise from your description,is it a round breadboard with a mosaic on top. (sorry to be so ablative,it's just the way my brain works!)

Originally Posted by doug boardley

trying to visualise from your description,is it a round breadboard with a mosaic on top. (sorry to be so ablative,it's just the way my brain works!)

yes, exactly, just that its thick exterior ply, so the edge isn't that neat, shaped and smooth would be better...getting bored with myself fretting about it...but a perfectionist to the end....
ablative ... very Latin...

Can you not just spread grout around the edges..then shape and smooth with sandpaper once set...?..

Originally Posted by Dave

Can you not just spread grout around the edges..then shape and smooth with sandpaper once set...?..

Or use a grout profiling tool?

Originally Posted by Mosaic Girl

yes, exactly, just that its thick exterior ply, so the edge isn't that neat, shaped and smooth would be better...getting bored with myself fretting about it...but a perfectionist to the end....
ablative ... very Latin...

grammar school education, think it was caesar who invented the verb "to ablate" well spotted!!

Originally Posted by Dave

Can you not just spread grout around the edges..then shape and smooth with sandpaper once set...?..

Dave and sWe - well I wondered about grout, but wasn't sure if it would be strong enough in all weathers without having much to cling to - you think it would be?

(and just in case any of you are wondering - the mouse has been liberated....)

Originally Posted by Mosaic Girl

Dave and sWe - well I wondered about grout, but wasn't sure if it would be strong enough in all weathers without having much to cling to - you think it would be?

(and just in case any of you are wondering - the mouse has been liberated....)

Murderer.....

Originally Posted by doug boardley

grammar school education, think it was caesar who invented the verb "to ablate" well spotted!!

yes, grammar school here to, cum, de a, ab, sine, pro, prae, is followed by the pure ablative (case ending), amo, amas, amat...eh, those were the days....

Originally Posted by Dave

Murderer.....

No, I meant set free alive and running......cat rewarded with a bit of ham...

Originally Posted by Mosaic Girl

yes, grammar school here to, cum, de a, ab, sine, pro, prae, is followed by the pure ablative (case ending), amo, amas, amat...eh, those were the days....

amatus amatis amant

Originally Posted by Mosaic Girl

Dave and sWe - well I wondered about grout, but wasn't sure if it would be strong enough in all weathers without having much to cling to - you think it would be?

(and just in case any of you are wondering - the mouse has been liberated....)

back to the thread that's what i did with my plant pots!

Originally Posted by doug boardley

back to the thread that's what i did with my plant pots!

Gratia cum laetitia, Dominus

Originally Posted by Mosaic Girl

Gratia cum laetitia, Dominus

et tu bruti, your thanks are gracious and eloquent, pmsl
ps I'm not really "God"

Originally Posted by doug boardley

et tu bruti, your thanks are gracious and eloquent, pmsl
ps I'm not really "God"

what's pmsl? Dominus as the master....but, of course, as you wish...

Originally Posted by Mosaic Girl

what's pmsl? Dominus as the master....but, of course, as you wish...

pee my self laffing

Originally Posted by Mosaic Girl

what's pmsl? Dominus as the master....but, of course, as you wish...

pmsl relates to urine and laughter,not latin; Dominus is way above Master, it is "The One"

Fruitcakes, both of you! And obviously most honorable and worthy Domini...love it...

and thanks again, will just use the grout now, what a relief! That means I can finish it tomorrow and stop fretting!

Originally Posted by Mosaic Girl

Fruitcakes, both of you! And obviously most honorable and worthy Domini...love it...

and thanks again, will just use the grout now, what a relief! That means I can finish it tomorrow and stop fretting!

good!! best of luck with it, dormi