I just opened my new set of cakes pans (14, 10 & 6 inch). It says to use the "Wilton Decorator Preferred Heating core". I don't have one and I don't think the hobby lobby or michael's here carries them.

I would order one, but I don't have time to order, ship etc.

If I can't locate one, is there something else I can use instead to help these 14 & 10 inch cakes bake properly? Any McGivor tips you have are much appreciated!

Also, how do you use one anyway? Online it says they are like 3 1/2 x 3 1/2 or so. That's pretty big. Is there a hole that big in the middle of the cake when it's done or do you insert the core after you pore the mix in??

If you don't have one, and I don't yet either, you can use a flower nail or two. I grease and flour my flower nail and then place it inverted in the middle of my round pan and then pour in the batter. I think one for 10" and possibly a 12" would be fine. I use 2 when I'm doing an 11x15.
The heating core works the same way. You spray the core, place it in the pan, then pour in your batter. Be sure to fill the heating core as well. Then when the cake is done, you can remove the core & plug the hole with the cake you baked in the core. Some people don't like the plug so they use the flower nail.

The heater core helps to distribute the heat through to the center of the larger cakes, assuring an even baking. Prepare the pan. I use homemade cake release with waxed paper on the bottom and then apply release to that, too. Then I cover both the inside and outside of the heater core with release, or spray with Pam, and place it in the center of the pan, hole side up. Fill the pan with batter, and also fill the core about 2/3 full. When the cake is baked, you remove the core which is filled like a "plug". I run a knife around the plug and let it cool on a rack while the cake is cooling. The plug is then inserted into the baked cake and trimmed or leveled as desired with the cake. (If I'm trying a new recipe I will often shave off a little of the excess from the plug to sample!) The plug fits quite nicely into the hole and none is the wiser when the cake is filled and decorated.
OK, that's my story on the heater core. I have since found the flower nail method to be just as effective and a lot less complicated. (Only no taste to sample here!) This might be your solution since you cannot obtain the core in time. Simply prepare your pan as usual. Place a couple of regular flower nails on the bottom, (the same thing you form icing flowers on---I know Michaels and Walmart carry them) and give them a shot of Pam then pour the batter in. When baked, invert the pan and the nail heads will be showing. Just pull them out and voila! I might over-kill, but I generally use about 3 nails, evenly spaced. I use them for pans 10" and above.
This is kinda lengthy, but I hope I've answered your questions. It's somewhat puzzling when you have never encountered them before.
Good luck.

Michaels in Tyler, has the heating core, or atleast they did. But I wouldn't worry about buying one. Just use the metal flower nail it is place.

Thanks everyone. I did locate one in Longview, but now that you mentioned the flower nail thing that might be easier and quicker. I'll give that a shot. Thanks!!

a bartender stainless mixing cup or a stainless steel canister that i bought in costco they are excellent for hat cakes. And bake perfect!!

If I'm using a heating core, should I use the baking strips around the pan as well?  Or is the heating core enough?  This would be for 10" and 12" round pans that are 3" deep.