How to Make a Smooth Aluminum Siding Corner

What You'll Need
Aluminum coil stock
Metal paint primer and paint to match
Adhesive or nails
Tin snips
Sheet metal pliers
Scrap lumber

If you have an older house, you may need to make your own aluminum siding corners to fit with the rest of your home's exterior. Follow the steps below to create aluminum corners with smooth finishes.

Step 1 – Create the Template

You will need remove a piece of the existing siding from your home to make a template. This way you will have the exact dimensions of the siding for your home and show you what the siding corner should look like. You will use this piece to make a template. Be careful when you remove it because there may be a nail that you can not see holding the top corner. You will also want to place it back on your home when you are finished.

Flatten the piece of siding with your pliers. This is now your template for shaping your pieces.

Step 2 – Make a Cut

Cut a piece of your coil stock to the rough size of the template. Trace the outline of this piece of flattened siding onto the metal. Use your tin snips to cut the piece out, being sure that it is exactly the same size as your template, including all notches.  Repeat this as many times as you need to make as many pieces as you need.  You should make a few extra pieces in case something goes wrong.

Step 3 – Make First Bend

Always bend the pieces in this order or it will not come out correctly.

You will make a lengthwise bend first. Mark the centerline with a marker. Clamp it tightly over your scrap wood, keeping the centerline on the wood at the edge but not over, bend the piece with your hands. You should bend to a full 90 degrees.  You may want to use gloves to handle the material.

Step 4 – Make Second Bend

Now you will bend the lip. This is the inner locking lip on the small sides. Using sheet metal pliers, make an inside bend at 90 degrees.  Do this on both sides of this end. Your second bend will create your bottom inner lip.  You are now looking at a piece of metal, folded in 90 degrees, with one long end bent inwards.  Think of how the piece looked that you removed from your house.

Only bend one of the sides. The other remains straight so that you can install it properly.

Step 5 – Install and Paint

You have now made your own siding corner and are almost ready to install it.  Before you place it on the house you should paint it.  It will be easier this way and you can touch up any parts after it is installed.  Use a primer and a paint color to match the existing siding as best as you can.

Once it has dried, you can install it in place. You can either use small siding nails or a strong water-proof adhesive.  The choice is yours.