How to: Apply ABS Paste
For those of you that are new and have just clicked on this thread because you're curious, you might be wondering what ABS paste even is and why I would be making a guide on how to apply it. The first thing you need to know is that ABS paste is, well, it's basically what the name suggests. It's a slurry made out of ABS scraps and acetone that you can use to fill in holes, thigh ridge gaps and cracks.
Because it's made out of scrap material from your armor build you don't even need to paint it after using it, because it's already exactly the right colour. The most you need to do is sand it down and polish it to match the look of the armor.
Simple enough, right? So let's get going!
First thing you need to do is make the paste! You can find a good tutorial over here: https://www.whitearmor.net/forum/topic/42866-how-to-make-abs-paste/
Because of something that I noticed with my first batch, I would like to suggest that you wash all of your ABS scraps and your jar before putting it all together so you won't have any debris in your final product.
So, I scrapped that one and started a new batch, where I washed every piece of scrap before I cut it and put it in the jar. It's looking much better than the other one, if you ask me.
In the next step, once you've got your paste ready to go (it should be the consistency of toothpaste) you're going to prepare your armor for applying the it. This means taking a piece of scrap ABS and putting it behind whatever you want to fill, so you can apply the paste onto that area and just use the paste to fill in the gap/hole/crack.
Time to apply! I've taken several pictures of my progress, I hope this might be helpful!
A quick reminder: please make sure to work in a properly ventilated area since you're going to be working with acetone.
First I gathered my materials - several sizes of wooden sticks, the ABS paste and (of course) the armor (the thighs in this case), where I had a piece of ABS with some tape to hold it in place. This keeps the paste from seeping through to the other side.
I actually needed two pieces of ABS due to the shape of the ridge -- one inside the ridge and one on top of that to cover the gap between the ridge and the cover strip. Whether you can reach your goal with only one piece of scrap or with several, make sure you've covered all the gaps that you need to have covered!
Time to apply the paste. Now you open that jar with the paste, have your wooden stick ready and preferably some tissue paper to the side for cleaning the stick. You can simply apply the paste by scooping some up and putting it into the gap. I've found that if the ABS just covers the tip of a toothpick, it was easy to get in the gap without smearing it all over or getting too much on there.
After ~2-3 layers
After applying layer I would press down with a clean toothpick to make sure it lays flat and that there would be no bubbles or gaps. I also used this time to push in any of the paste outside of the gap. Because of the fast drying consistency of the paste, it felt like moving around chewing gum that has been chewed on for a few hours already.
Remember: every bit of paste outside of where you want it is going to have to be sanded. So go slow, work carefully and you'll be able to save yourself some time.
I repeated this process several times until the paste matched up with the armor.
The closer I got to the top edge of the armor, the smaller the drop of paste got. I had to clean my toothpick every now and then to make sure that I could still work cleanly. I also had to add a drop or two of acetone every now and then to my paste in the jar and stir it in with a toothpick, to make sure the consistency stayed roughly the same and that it didn't harden in a layer at the top.
Once I got to a point where I was happy with the results, I closed the other gaps as well in the same way. Afterwards I went back to this one and closed up a few spots that weren't as clean as they could be and still had some gaps.
Once it dried, I took some scissors and cut away the visible part of the tape that wasn't covered with the paste.
Next I had to wait until it dried (about 24 hours) then sand the paste smooth and maybe cut the return edge so it looks smoother. Once I've got it sanded down, I'll see if there are any gaps that I've missed that need another bit of paste, fill them up, sand it down and so on until I'm happy.
If you worked carefully enough, you might be able to skip sanding because it's already flat and aligns perfectly with your armor. If that isn't the case, here's a great tutorial on how to get things sanded shiny again: https://www.whitearmor.net/forum/topic/45052-howto-wetsand-polish-for-a-great-shine/
I hope this could help you!
At this point a huge thank you to @justjoseph63 who inspired this, proof-read and helped with editing the pictures!