Rawl Plug Blues

[custard]

I've got a series of fairly heavy shelves and brackets that need securing to both brick and breezeblock walls.

I've tried three different brands of rawlplugs, two different brands of 10mm SDS drill bits, and two different brands of M8 x 80mm screws.

With almost every combination the screw won't tighten sufficiently without rotating the plug in the hole. The one exception is a style of rawlpug that has a lip at the end, this works every time but the lip protrudes by about a mill, so it's no good for when you want the workpiece to be fastened flush against the wall.

I guess the options are,

-pack out the hole with Pollyfilla or some other kind of gunk
-try an M10 x 80mm screw (screws in this size aren't common and start to get pricey)
-trim off the protruding lip on the functioning brand of rawlpug or counterbore the workpiece (slow)
-going forward use a 9mm drill (but still need a solution for the existing holes)
-track down a brand of flush fitting rawlplugs that does what it says on the tin

Anyone got any (useful!) advice?

Thanks

 

[Woodmonkey]

Squirt a bit of gripfill in there before the rawl plug

 

[MMUK]

In the brick, a 6.5mm drill and use 7.5mm direct fix bolts with the Torx head. For the breezeblock or ash block walls, a 4mm drill maximum or no pre-drill at all.

I've been using them for fixing virtually anything to walls for years now. You can get them in 62mm, 82mm, 102mm, 122mm, 152mm and 182mm lengths.

Tip: Buy them from a Eurocell Building Plastics trade counter in boxes of 100. I pay just over £8 with VAT for a box of 122mm bolts.

 

[Phil Pascoe]

On existing holes use a water based adhesive like "no more nails" to stick your plugs in. Blow the holes clean of dust first. Obviously leave the stuff to dry properly - this works for most crumbly walls. Otherwise as above or use "Thunderbolts"

 

[custard]

Thanks for those comments, that's pretty much what I thought. I tried Eurocell but they don't stock those screws on their web order site, no matter though as I tracked down an alternative and I'll give them a try. For the exiting holes it's a squirt of Pinkgrip.

Wish there was bomb proof rawlplug out there though!

 

[Roughcut]

The best one's I've used are the Fischer brand rawl plugs.
They are better than the cheap tapered rawl plugs anyway.

 

[petermillard]

Are you sure the 'breeze blocks' aren't Thermalites? They're very soft and need a particular type of plug; I've used these - http://www.plasplugs.com/acatalog/Therm ... xings.html - and another type where you screw the plug into the wall, then hammer in a little pin into the side of the plug that prevents it turning.

Otherwise (and in addition to all the above) there's always resin...

HTH Pete

 

[Deejay]

Afternoon Custard

Toolstation sell them, as you may know ....

http://www.toolstation.com/shop/Screws+ ... 950/p58193

The best plugs I've found for lightweight concrete blocks are these ...

http://www.toolstation.com/shop/Screws+ ... 060/p10606

The trick is to drill the hole as small as you can and fit the plug with a hammer.

You can also lubricate the screw thread with candle wax or similar.

Cheers

Dave

 

[caroleb]

I have some 6mm red hilti plugs - I am sure you would be able to get them in other sizes though. They are absolutely fantastic - I have never seen or used anything like them. I have had one fail in about a thousand, I pulled the plug out and tried to remove it from the screw. I ended up having to cut it off with a stanley knife.

If you like I can find out what they are called.

HTH

Caz

 

[chippy1970]

The trick is to drill the hole as small as you can and fit the plug with a hammer.

Cheers

Dave

+1 for that, I normally just use screws and standard Brown plugs for most things. If it's soft blocks then I just reduce the bit size the 6mm and hammer a brown plug in tight.

Sent from my HTC One using Tapatalk

 

[carlb40]

The trick is to drill the hole as small as you can and fit the plug with a hammer.

Cheers

Dave

+1 for that, I normally just use screws and standard Brown plugs for most things. If it's soft blocks then I just reduce the bit size the 6mm and hammer a brown plug in tight.

Sent from my HTC One using Tapatalk

Same here only i turn the hammer action off to get a cleaner hole

 

[Duncan A]

Fischer Nylon UX Universal. Never let me down in hard brick, soft brick, hollow brick, breezeblock, plasterboard. Haven't tried them in Aircrete but Toostation say "Premier high quality nylon universal wallplug, suitable for all building materials and pre-positioned installation."

I don't bother with cheaper plugs any more.

Duncan

 

[Stu_2]

+1 for Fischer plugs. They're very good. For dodgy holes, I normally knock a match, or two, down the side of the loose plug.

 

[nanscombe]

You mean you don't use the old tin of (white asbestos based) fibre that my dad used to use?

...
One of the first of these mixtures was produced by Rawlplug and was composed of dry white asbestos fibres, sold loose in a tin. The user wetted some into a ball (usually by spitting on them) and pushed this plug of putty into the hole. A small tamper and spike was supplied with the kit. This putty worked very well, but the hazard of the asbestos fibres means that the product is no longer available.
...

Drill a little hole using a Rawlplug masonry chisel and club hammer
Grab a pinch of the fibres
Spit in your hand
Roll into a little sausage
Pack it into the hole with the little spiked tool
Drive in the screw

Simples. :mrgreen:

...
However, another way to fix wall plugs is accomplished by the application of a cotton weaved pad which has been impregnated with a special formulated gypsum to bond into the wall. The pad is wetted and wrapped around the wall plug, and the two are inserted into the hole; after a short time it hardens and a strong bond is achieved and the wall fitting can be applied. It is used in combination with wall plugs in masonry, ceramic, wood and plasterboard walls.
...

I guess WetNfix is the modern equivalent, £6.29 for 50.

An interesting comment was made by someone ...

... They are circular cutouts from a plaster of paris bandage, the same used for fractures in health clinics.
They do work well for dodgy wobbly plugs, but rather expensive for what they are!"

Modrock Plaster of Paris Bandage 6cm x 2m x 6rolls - £5.25.

 

[Silas Gull]

8 or 10mm 120 frame fixings wound in real slow. Don't overheat the plug.

If the substrate disintegrates, consider an epoxy filler.

 

[Silas Gull]

Consolidating the substrate could involve some PVA or whatever. This sounds like an irregular jiggery pokery, razzing out in a mortar bed or simply some bad karma with a foreign drill bit. IMHO.

 

[Silas Gull]

Or counter sink the bracket/whatever to accommodate the lip. Sounds like a compromise is in order and the plug will have to go through the unit. You gotta see the bigger picture.

 

[Silas Gull]

Yes, frame fixings through the unit, wound in real slow on a low clutch setting should sort it. You'll love it.

 

[chippy1970]

The trick is to drill the hole as small as you can and fit the plug with a hammer.

Cheers

Dave

+1 for that, I normally just use screws and standard Brown plugs for most things. If it's soft blocks then I just reduce the bit size the 6mm and hammer a brown plug in tight.

Sent from my HTC One using Tapatalk

Same here only i turn the hammer action off to get a cleaner hole

Yep that too

Sent from my HTC One using Tapatalk

 

[RossJarvis]

Generally speaking I have never had luck drilling and plugging masonry walls. In brick, it seems best to not use hammer of any type, unless using a bit of smaller dimensions than the plug and I always seem to end up wrapping the plug in paper to get it to stop spinning in the hole. I think this is an art that needs much instruction in. My experience seems to be that the plaster covering has little strength and falls apart and the underlying brick often does similar.

I also discovered that Erbaur drills from Screwfix are not straight and make things even worse. Personally I'd now rather not do anything that involves drilling and fixing into walls full stop.