Tapping Holes and Screwing In The Eye Kit

Step 1:

Get together the tools you will need to tap holes in plastic, or for that matter, any material.

You will need a through-hole drill bit

(that is one that is just big enough to let your screw pass through without catching on the threads. In this case, we will be using 6-32 1/2 inch long machine screws with pan head Phillips heads, so a number 28 bit is what we want here)

You also need a tap hole drill bit.

(that is one that is a little smaller than the hole you need to thread the screw into. Then you use the tap to cut the threads into that hole)

You need the tap

(again, we will use a 6-32 tap here. You can buy them anywhere, but all the info can be found on McMaster-Carr by typing in that part number)

And you may want the optional Tap " T " Handle. Alternatively, you may carefully use a variable speed drill to tap into plastic. We will show you how later on.

Step 2:

Once you have your tools, get out the template that you printed out from the first tutorial.

We will use the Lindberg template here.

Step 3:

Strip all the parts off the servo plate and lay it on the template to be sure that the template did print out in actual size.

Step 4:

Mark a couple of spots where you will put in the screws to hold the eye kit bracket in place.

Placement is not critical, but try to space them out evenly and be more or less centered as to where the bracket will be.

The lower picture shows it without the template to make my dots easier to see.

Step 5:

You will use the #28 drill bit here because you want the screws to pass freely through the servo plate and thread into the eye kit bracket.

So put the #28 bit in your drill and get ready.

Step 6:

Drill holes as straight as you can right where you marked the spots on the servo plate.

Use a drill press if you have one.

Step 7:

Now, put the servo plate back on the template and draw out the outline of where the eye kit bracket goes.

Step 8:

Position the bracket within the bounds of the box you drew with your sharpie.

Step 9:

Grab a thin tip marker and mark the spots in the bracket where you need to tap holes by poking the thin tip through the holes in the servo plate and marking the edge of the bracket

Like this....

Step 10:

It should look something like this....

Here is just the bracket. By the way, I am using a piece of plexi the same size as the bracket here so it's easier to see instead of an actual eye kit with all the parts on it, but you get the idea.

Step 11:

Now get out the #34 drill bit and get ready to tap some holes.

Again, drilling as straight as possible (use a drill press if possible) drill down into the bracket about 1/2 an inch in each marked spot.

Step 12:

It should look like this when you are done.

Step 13:

Now, if you feel comfortable controlling the variable speed drill at VERY slow speeds, put the 6-32 tap into the drill.

Step 14:

Aiming down again as straight as possible, VERY SLOWLY run the drill so that it starts cutting the threads into the hole. By slowly, I mean maybe 3 or 4 RPM slowly.

If you spin the drill too fast, you will strip the whole thing out and will have to start over with another hole in a new position.

Step 15:

If you are not comfortable with the drill, put the tap in the " T " handle tap grip and tap the hole manually.

Just line it up straight and turn slowly while pushing down gently.

Step 16:

Get out two 6-32 one half inch long screws. 5/8 long will also be OK.

Step 17:

Push them through the servo plate so that they stick out the bottom of the plate.

Step 18:

Now lay the plate over the eye kit bracket and screw it down into the holes you just tapped.

Step 19:

You can see the threads that were cut into the plastic and you can see how far down the screws go into the holes. from the side.

Step 20:

Just another view showing you the type of head you want on the screws.

Step 21:

This view shows you that the bracket is bolted in place, right where you wanted it to go.

If you find out that it needs a slight adjustment, you can remove the bracket, and drill out the holes in the servo plate a little bigger. Then you will have a little play where you can move the bracket around before tightening down the screws for the final time.