When I was young, I would often try to remove the parts from the sprues before they were ready. I knew about x-acto knives, but my parents wouldn’t let me use one without supervision. I was very impatient and just wanted to start making models of cars and planes. Unfortunately, this often resulted in parts being missing or part of the sprue still attached.
When you are new to modeling, it is important to learn how to do it correctly. I made a lot of mistakes when I was starting out, so hopefully you won’t make the same ones. Here are some tips that will help you out.
The steps to getting clean parts from sprues are as follows:
- Use flush side cutters to cut the parts away from the sprues.
- Remove the extra plastic leftover from the molds.
- Use a file to make the area smooth and match the rest of the part.
Use a Pair of Flush Side Cutters
Using a good pair of cutters will help you remove the parts from the sprues while leaving the least amount of material hanging on. Turn them so that the flat side is closest to the part you are removing.
If the part is packed in pretty tight and you can’t get around it easily, then cut further away on the sprue so that you can remove it and then trim closer once you have it separated.
This model part, for example, is difficult to cut near it. But when I intentionally leave a big part of the sprue, it makes it easier to get the sprue parts cut off.
Trim Flash with a Sharp Hobby Knife
Models are often created in two-part molds. In this process, the plastic or other material is poured or injected into the mold. Sometimes there is a small amount of material that will be forced out in between the mold sections. This extra material is called flash.
You can see in this photo that there is a lot of extra material on this sprue. If this was on model parts, you would need to carefully trim it off with a sharp hobby knife. This is not a common problem, but it can happen.
Remove Mold Lines
Mold lines are the most common type of flash that you will encounter in modeling. This is where you will have a small line that will show up on the side of a model piece. They generally aren’t very pronounced and can easily be missed before you paint.
Missing some of these small imperfections can be a problem when painting models. This is because many painting techniques make them look worse if they are not done perfectly.
I have found the easiest way to remove them is to scrape the back of your hobby knife along the line. You will see the plastic curl up and come off as you scrape. I have to emphasize the importance of patience and a light touch. It is very easy to damage the soft plastic that models are made from if you are not careful.
A Good Set of Files will Help to Round things Out
After I trim the area neatly with a hobby knife, I will run my fingernail over it to see if there are any small imperfections left. If there are, then I will use a small file to help smooth it out.
Take care when filing the soft plastic pieces because it is easy to remove too much and deform the part.
How do you remove a model from sprue?
To remove a model from sprue, use a sharp knife to cut the connection between the model and the sprue. Be careful not to cut too deep and damage the model.
How do you separate glued model parts?
Use a sharp knife to cut the connection between the model and the sprue. Be careful not to cut too deep and damage the model.
How do you cut model kits?
You can use a sharp knife to cut the connection between the model and the sprue. Be careful not to cut too deep and damage the model.
How do you clean a sprues flash?
To clean a sprues flash, use a sharp knife to cut the connection between the model and the sprue. Be careful not to cut too deep and damage the model.