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Can You Sand Decorators Caulk?

Decorators caulk is a vital product for helping any level of decorator achieve a professional level finish. Many novice users may not be that familiar with decorators caulk and wondering how to achieve the perfect finish. This may lead to you wondering whether you can sand decorators caulk, well can you? Let’s jump in and have a look.

Trying to sand decorators caulk

The easiest way to get to the bottom of this question is to simply test it. I will put some decorators caulk on a bit of scrap wood and then see if it is possible to sand it down to a nice finish.

The rough decorators caulk, will it sand

The rough decorators caulk, will it sand

This is the caulk I will be attempting to sand. I have made it rough intentionally so we can see how well the sanding attempt goes.

After a bit of sanding

After a bit of sanding

After a bit of sanding with some Mirka 120 grit paper. You can see from the photo that not much has actually happened to the caulk. But there is a lot of debris that has come off the caulk.

The bits of caulk that come off

The bits of caulk that come off

Here are all the bits of caulk that have come off. It is almost the same as the stuff that comes off a rubber when rubbing out some pencil.

This is because the dried caulk is quite rubbery and so does not sand into fine dust like Polyfilla would for example.

After more sanding

After more sanding

After a bit more sanding the caulk now looks like this. You can see that it has actually sanded a bit more smooth than it was to begin with.

This was quite a bit of effort though and it is obviously far from being smooth. So with that in mind, I will continue sanding the decorator’s caulk and see what happens to it.

After a lot more sanding

After a lot more sanding

This is what happened after I really went to town with the sandpaper. You can see that the finish on the caulk has been destroyed, this definitely didn’t work.

The darker areas are not a mark on the caulk but actually an area where it has been sort of scuffed up. Based on this evidence you cannot sand decorators caulk. It worked for a little bit at first but if you try and actually flatten the caulk out you just end up destroying it with the sandpaper.

So if you cant sand decorators caulk how do you get it smooth?

The Finger Trick

There is one time served way of smoothing down caulk, and that is by simply using a wet finger. It used to be that the decorator would simply lick their finger to wet it before smoothing the caulk down. This has gone out of fashion lately though as it is believed the bacteria introduced from your mouth can actually speed up the formation of mould on the caulk.

Now the done thing is to have a pot of very slightly soapy water on hand. Just keep dipping your finger in it and smoothing the caulk down, it’s really simple. I have a few photos below for you showing just how easy it is to smooth the caulk down.

a fresh caulk bead

a fresh caulk bead

Here we have some fresh, lumpy caulk, straight out of the gun. Time to see if we can smooth this out into a really nice finish.

Wet your finger

Wet your finger

And this is the general strategy to smooth it out. Simply run your finger up and down smoothing the caulk out. It is essential that your finger is wet for this or the caulk will simply stick to your finger.

It used to be that you would just get some Slavia on your finger and use that to wet the caulk. That is frowned upon now as it is believed it will speed up the growth of mould on the caulk.

Smoothing the caulk out

Smoothing the caulk out

Here you can see just how smooth you can get the caulk and get it there fairly quickly.

A nice smooth finish

A nice smooth finish

So there we have it, the smoothed out caulk.

As you can see this is a great finish, and soo much better than trying to sand the caulk down. If you want a nice smooth finish when using decorators caulk then simply do this to smooth it out.

There are silicone smoothing tools that you can use to do the same thing, some are shaped to help you get a specific shape on your finished caulk. These can work really well if you want to buy one, it’s just they are not always needed.