How do you do it?
Even the grocery store cakes are perfectly iced, but I can't seem to get my tops smooth, flat and blemish free, not even on my rounds.
I bought a giant painters edger, but I still can't get the hang of it.

Are all spatulas created equal or are there higher performance ones than Wilton (like there are better cake pans such as Magic Line).
Is my icing not the right consistency?

I shy away from sheet cakes for this reason, but I still get requests and I cringe when I do.

Is there a secret? I'll take any tips.

Have you tried using a plastic scraper? It also helps if the icing is smooth to begin with.

I feel ignorant...but what is a plastic scraper, and is there one big enough to smooth a sheet cake?

what tool do the grocery stores or bakeries use?

Wondering the same thing...if there was a better trick out there...I HATE icing sheet cakes!

http://bakerycrafts.com/Home/Items/tabid/69/SrchStr/scraper/Default.aspx

If you're using a crusting butter cream ice your cake then let it crust about 5-10 min then lay a viva paper towel over the top and using the palm of your hand run it over the paper towel then lift it should have a nice smooth surface; repeat in sections and dont forget the sides. Hope that makes sense

i like the large wilton 15" spatula to go across the top of a sheet cake, but after smoothing the best i can with that i still use a viva paper towel and a fondant smoother on top, takes just a couple of minutes to get it perfect.

Viva & Crusting BC is what I do, I was hoping for something "magical" LOL!

try using the Melvira method. She uses high density foam rollers on crusting b/c.
http://cakecentral.com/articles/126/quick-easy-smooth-icing-using-a-roller-melvira-method

I've found I can get a smoother finish if I use a scraper like the ones posted in that link versus using an offset spatula. It's something about how you hold the scraper that gives me a more even finish. Even using a credit card works well too. I have a pic in my gallery of a cake with a red rose on it. That one was iced with bc, I used a credit card to smooth and then Viva'd it. It looks like fondant, it's so smooth.

You can try using one of these, a 16" stainless scraper by PME: http://www.cakedecoration.co.uk/merchant.ihtml?pid=9388&lastcatid=82&step=4
Or, a 12" plastic or metal school ruler will do the same thing essentially. Grab it by the top corners/sides, and drag across the top of your cake. Then smooth out the edges as usual.
It takes some practice, I don't do many BC cakes at all so I haven't practiced enough!

is there something special about 'viva' brand paper towels that makes them works better?

Viva doesn't have a design impressed in it, it's perfectly smooth. You can also use computer paper.

After icing the cake, let set for 15 minutes. Then once the icing has crusted over, take a parchment triangle, used to make icing cones, and lay it on the cake and take a metal spatula and smooth the parchment triangle. The icing must be set or crusted over or the icing will come off onto the parchment triangle. You might have to use a couple of triangles since each one should only be used 2-3 times to smooth the icing.

I am a newbie to cake decorating and this works beautifully.

I suppose you could even use standard parchment paper that comes on a roll too. I just have always used a triangle because it is what I have on hand.

If you want a bigger spatula go into the drywall section of the hardware store you can get big one there that are either plastic or metal.

ah, that makes sense, thank, dnaboo. i thought that may be it, but for all i knew it had some kind of weird coating on it, lol. i guess, though, that if you really loved the pattern on 'brawny' then you'd use that, eh?

I just use the plastic scrapers and a turntable, but I use a non crusting buttercream. All of my cakes look as smoth as fondant. I think part of it is also just practice, practice!

Any tips for the top edge of the cake? I always wind up with a ridge. If I smooth the top it pushes out to the side, then when I smooth the side it pops up on top! It is almost funny but frustrating.

Cool! Thanks for the explanation That sounds like something I'll need to practice. And yeah - its inmportant to avoid that discolouration. I think working faster with SMBC goes a long way to helping avoid that too.

Thanks for the tips! I have used both the Viva and Melvira methods, but still can't seem to get the hang of a perfectly smooth top of the cake and any cake that is wider than the paper towel or foam roller. The cardstock tip is new to me, do you use it like a scraper? I have used a bench scraper for the sides of cakes, but again they were never wide enough to do the top without leaving a line. Thanks for the other tool recommendations.

I have always wondered how the supermarket bakeries do it when they surely don't have the time to obsess over perfection. Anybody know? I'm sure they are very practiced, but what method or tool do they use?

OK Buddy's icing video...

http://tlc.discovery.com/videos/cake-boss-icing-a-cake-buddy-style.html

That is exactly how I do it also, except I use plastic instead of posterboard.
Works everytime.

I also saw that episode of cake boss and was wondering if anyone else uses card stock as a scraper. He didn't smooth with it the way you would viva. He used it as a scraper. And it seemed to work like a charm.