Caring for your IDS Chalkboard Art
PLEASE NOTE: unsealed chalk and chalk ink will run if it gets wet! You might be able to touch it up with a damp Q-tip or pencil eraser if the damage is minimal but if it's extensive you will not be a happy camper. So to prevent unhappy campers, you have two options; sealing your sign art or not sealing and keeping your sign dry.
If your piece needs to be sealed, I recommend a spray sealant, ideally in a matte finish (the flattest, un-shiny finish available) or satin in a pinch. In a real pinch, you can use good ol' hairspray. Hairspray may not be the best for the long haul, but it will get you through a damp day and since it's typically handy it can be used as a fixative. It also has the benefit of being temporary. If you wanted to remove the hairspray (and the design) try rubbing alcohol for an instant do-over. For long-term protection from the elements, however, you'll want to seal the sign proper like. There are many different sealant brands available and they all get the job done. You can find any number of them at your local craft store, art store or home improvement store--pretty much anywhere they sell spray paint. The most important part of your sealant purchase is that you get a matte finish that is a SPRAY on. [Do not try the brush on variety. I assure you it will make a hot mess of your chalk artwork.]
Here are just a few brand examples you will find. Pick what is available and a good price.
Chalk Ink Erasing Tips
Often after you attempt to erase Chalk Ink with water, a shadow of the design remains on the blackboard, especially if this was the DIY chalkboard paint, which is very porous. This shadowing is also referred to as being "burned in" and can even happen with chalk as well so I wanted to include these erasing tips for any DIYers out there experiencing "shadow pains" as I like to call them.
So let's say you tried water first to erase your chalk ink and you can still see a shadow of the design. Next, you can try a product that contains ammonia. Windex has a little. Shadow still there? Sometimes they will resist the first two cleaning attempts--especially if this is on DIY chalkboard paint. Try a magic eraser next (Mr. Clean brand or a generic brand will both work great). It will take some elbow grease and may also remove some of the blackboard coating, but often this does the trick. And if all that fails, paint over it all with another coat of chalkboard paint.
Side note, if you are trying to erase on a DIY chalkboard surface and don't feel like hassling with all the cleaners and whatnot, you could always skip those and just resurface your blackboard from the get-go--just give it a water wash first then repaint with your chalkboard paint when complete dry.
Water Erasing Chalk - WARNING
Did you know that the binding agent in chalk is often clay and when you use water to clean a chalkboard it makes the clay dry and hardens in the pores of the board? The hardened clay can build up to the point the board becomes gray or hazy. It can even make the board slick so chalk won't work on it very well anymore. I've definitely encountered old/antique chalkboards with "chalk issues." There is a special chalkboard erasing cloth made to fix the problem. Here is a link to the company that makes them Braham Chalkboard Cloth or you can find them on Amazon too. (I love Amazon Prime, don't you?)
Chalk Erasing Recs - Save your board from "Chalk Issues"
To prevent ruining your boards with water, use a dry microfiber cloth for erasing chalk dust from your board as much as possible and a wool felt eraser when you want to keep the dust around but smear out the design = "smoky affect."
Not Sealing Tips
You can choose to leave your sign unsealed and just be careful that it does not get wet or handled extensively. This is a perfectly good option and I assure you that it will last and remain lovely for a very long time this way. The bonus of this plan, if you ever want to change the design you can erase all or part of it as needed/desired. Maybe you want to update the wording and keep the decorative part. Or maybe you just want to start over. It's nice to have options. Just saying.'
As mentioned, the key thing is to get a SPRAY sealant with a MATTE FINISH. Some helpful but not deal breaker bonus features would be Non-Yellowing, UV Resistant or Outdoor. These are good to have if you plan to use the sign outside at for any extended amount of time. One day at a wedding does not require an outdoor or UV sealant--but it also won't hurt.
Once you get your sealant, just follow the directions and safety precautions on the can for your brand. However, I highly recommend you do a little test piece first with the medium you are using (chalk, pastels, chalk ink, etc.) on a scrap piece of board. There are certain combinations where the spray could make the art disappear (that happens most with colored mediums). Either way, the most important thing is to apply several thin layers from 12 inches away. You don't want drips and you do not want it to hit the board wet!!! Oh and don't breathe the stuff for goodness sakes. Nasty!
Lastly, in case it's not obvious, please be aware that if you choose to seal your sign with anything stronger than hairspray (even 'workable' fixatives), you will no longer be able to erase the design. It will be there permanently. Always. Forever. Unless you paint over it with a coat of chalkboard paint and start again.