The Rawlplug FAQ

What on earth is a Rawlplug?

It is a fastening which allows you to fix objects to brick, masonry, or concrete. A hole is drilled into the floor or wall, an insert (now normally plastic) is put into the hole, and a screw is driven into the insert. The screw expands the insert sideways, and it grips the inside of the hole tightly.
 

Why is it called a Rawlplug?

After the inventor, John Rawlings. In the early 20th. century, he devised a brass cruciform plug to fix something to a wall. Later on he created a plug made of jute bonded with animal blood. Due to the intervention of WWI the Rawlplug company was not formed until 1919. The term is now generic, like Hoover, i.e. any similar product tends to be called by the Rawlplug name.
 

I can never get them to work, what am I doing wrong?

For a Rawlplug to work correctly, the hole, the plug, and the screw must all match in size. For the majority of DIY work, a No.8 masonry drill (6mm), No.8 plugs (red if from Rawlplug), and 1 1/2" No.8 screws are a good choice. My personal recommendation is to use Supascrews. These can be recognised by
 
  1. The heads are usually Posidriv.
  2. They do not taper.
  3. The thread runs all the way to the head.
  4. There are actually two threads, running parallel.
WARNING: Before you drill make sure there are no services (electric, water) where you are going to drill. Cable and pipe finders are relatively cheap. Normally power cables run vertically down the wall to switches or sockets, so beware drilling over these.The hole must be deep enough for the screw not to bottom out. Naturally you should use a hammer drill with the hammer action on, and with the chuck done up tightly. Excess dust in the hole can cause trouble, so either vacuum out the hole as detailed below, or keep the drill running, and "pump" it in and out a couple of times. When you have drilled the hole, insert the plug, rounded end first into the hole, flush with the wall, or perhaps slightly deeper. If you have any rawlplug protruding, you will not be able to fix the object tight up to the wall. Now screw the object into the plug. Done! (I know this may seem obvious, but some of the people reading this may be tackling their first DIY project) If you are fixing to bare brickwork, try to get the plugs into brick rather than mortar. Some mortar is very soft, and will not take the imposed load. If the plasterwork is particularly thick, drill a deeper hole, push the plug fully into the masonry/brickwork, and use longer screws.
 

Blimey O'Reilly! I drilled into the wall, and there is a huge hole behind the plaster. What now?

Don't Panic! Have a look at the plaster. Is it whitish and crumbly, with sandy bits in it, and possibly horsehair, and on an interior wall in an old house, and you can see wooden laths behind it? Now you can panic! Either decide to put the shelves on an exterior wall, or have that one replastered with plasterboard (see below) The other common possibility is that you are trying to put up a curtain rail. Rather strangely, although this may seem like a good starting project for a fledgling DIYer, it is a job with several potential pitfalls, as you will see below. Above a window is normally a concrete lintel, and the builders of your house weren't very scrupulous about mortaring it in completely, so there is a void behind the plaster. Attach a small tube, e.g. a McDonalds straw to the smallest nozzle on your vacuum cleaner with insulating (or sello) tape and suck all the loose stuff out of the hole. Be thorough. Now fill the hole with a good quality ready-mixed filler and leave it to set for 24 hours. If you cannot wait 24 hours, and the missus is looking at you like that again, use car body filler and have a cup of tea while you contemplate the futility of life. The body filler should be set inside 30 minutes. When the filler is set drill a 3mm hole using a twist drill, no hammer action in the correct place and screw directly into it. N.B. this is OK for curtain rails, but the holding power will not be as good as a Rawlplug. Note that you should drill all your holes before remediation, because odds are the same thing may happen along the whole lintel, and particularly at the ends.
 

It's that bloody curtain rail again! I am trying to drill a hole over the window, and the drill is on hammer action, but it's going nowhere. Why me? What did I do to deserve this?

CAUTION the drill bit may be very hot. The aesthetics of curtains are that the curtain rail normally looks best just above the window, i.e. fixed into the lintel. The lintel is made of concrete with some reinforcing steel, and the concrete has flint aggregate. Have a look down the hole. If it looks like steel you can either persevere with the masonry drill, or, better fit an ordinary twist drill an use no hammer action for a bit until you can see no steel. (this will ruin the drill bit) Otherwise it is a bit of flint. Get a masonry nail (or a Rawltool if they still make them*) and hammer it hard into the flint a few times. It should then drill out nicely.

*They do.

How much will a Rawlplug carry?

The combination above, If fixed correctly in a good wall should safely carry 50kg in shear or 25kg in tension. The filler technique is not so good. In either case, an extra fixing never did any harm, at least not to my knowledge.
 

My wall is made of plasterboard. what can I do?

There are special fixings made for plasterboard. There are several different types, but they all seem to work. Read the instructions carefully.

How do I deal with tiled walls?

Ideally put some tape on the tile. This stops the drill from "skating" all over your nice, shiny tile. Then drill through the tile without hammer action. when you are through the tile engage the hammer action, and drill the rest of the hole. Then try to get the rawlplug itself deep enough into the hole so that it is not in the tile. This is to avoid the risk of cracking the tile.

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John Schmitt 

Last updated 18/04/00