Rimless wall plugs, minimal taper?

[harryagain]

You should have used plastic skirting. Quite flexible and can be warmed to make it even more so.

[David]

The skirting board fixing is progressing.

The MDF skirting for the bay is now bent almost to fit, and just needs pulling in that last little bit with screws into the wall.

For the rest of the skirting I've used 5 * 50 screws and red wall plugs (5mm drill), and these have been fine.

However they are not strong enough to pull the skirting in snug - they almost get there, then the screw rips the plug apart and the whole thing slides back.

So I need to upsize everything.

Next up in the Rawlplugs are brown. The strip they attach to says 7mm drill and 4-6mm screws. However the brown wall plugs are more than 7mm across the wide end.

Presumably this is so that when you drill into a plastered wall then push in the plugs the flared end sits into the plaster and never gets to the brick/block.

The plugs are also quite short, although I assume that a short plug in a long hole with a long screw would work.

Because the skirting is bent and under some tension I can't do the usual trick of drilling holes, marking through, drilling the wall and fixing the plugs, then offering up the board to the holes.

In fact, the skirting will move slightly as it is pulled in, so pre- drilled and marked holes won't line up.

So I need wall plugs without a flared out end and a rim so I can drill the hole through the board and the wall, push them through with the screw, then screw into the wall and pull up tight.

Google does offer some choice, but I am looking for recommendations for something which will suit a 6mm screw about 60mm long (unless I need to go even larger).

I don't have the right size screw anyway, so game over for today.

Cheers

Dave R

[JimK]

The skirting board fixing is progressing.

/The MDF skirting for the bay is now bent almost to fit, and just needs pulling in that last little bit with screws into the wall.

For the rest of the skirting I've used 5 * 50 screws and red wall plugs (5mm drill), and these have been fine.

However they are not strong enough to pull the skirting in snug - they almost get there, then the screw rips the plug apart and the whole thing slides back.

So I need to upsize everything/q Snip>

Difficult to imagine without a PIC but...

How many screws are you using to pull this MDF in? How thick, tall, long is it? What shape are you trying to force it to be?

Jim K

[David]

Nothing like 20/20 hindsight in there, Harry?

[David]

Will post pictures soon.

18mm thick, about 150mm tall, bending into a semi-circular bay window.

I will use as many screws as required to pull it in - I expect to have one every 250mm for about a 3 metre length to maintain the curve.

Cheers

Dave R

[David]

Supplementary - I have just turned up some 6 * 100 screws.

Now a house brick (or comparable wall block) is about 100mm deep. The skirting is 18mm thick. So the screw should go into around 75-80mm of wall, depending on how thick the plaster is. So if I were to drill an 80mm deep hole it would be less than one brick/ block depth, with plenty of length to grab hold of a wall plug. However the wall plugs are only about 30mm long.

Any reason why you can't push two wall plugs one after the other into the hole, for twice the grab?

Cheers

Dave R

[Tim Watts]

I had *exactly* the same issue.

You don't need bigger screws - you need better plugs, assuming you have brick walls (do you?)

Fischer Type S is what I used, with 5mm x 50mm stainless wood screws (oak skirting):

I *believe* the woodscrew is a better choice here as it has taper which a lot of "modern" screws don't. So I'd switch your screws too.

I had to pull in quite tight against a slightly curved wall in places and this combination were excellent.

Now what I cannot remember if if I used S8 (8mm hole) or S6 (6mm hole) plugs. Pretty sure it was S8's though the S6 will take a 5mm screw.

I am almost complete certain I was not using 6mm screws.

[Tim Watts]

That's a bit excessive for skirting!

Last time I used screws like that, it was to fix actual door frames...

[David]

Thanks - so happens I have a box of Fischer SX 5, 6 and 8 but I ruled them out because they have a slight rim. Looking at the link, the ones you used are rimless so look a better option.

The 100mm * 6 screws I found are wood screws - point taken that most modern screws are designed to chew through wood without pre-drilling which is not perhaps the best match to plastic plugs.

The outer wall of the bay (and the rest of the house) is brick, but the inner walls are mainly block, although a curved bay is more likely to be brick than block. Should have drilled a test hole first.

Now where to get the plugs?

Screwfix don't offer Fischer S but the do offer nylon plugs which look very similar

Toolstation do offer S plugs :-) I assume that when they say 6mm they mean the screw size, not the plug size? The SX ones I have offer no guidance about screw size or drill size.

Proper wood screws seem a problem as well - very few seem to come with the smooth neck of the traditional steel wood screw (I have a stock of old slot head steel screws but I don't trust the impact driver not to chew the heads up - Posidrive are much more useable).

Anyway, shopping day tomorrow :-)

Thanks

Dave R

[The Medway Handyman]

Have you kerfed the back of the skirting?

Ordinary plugs or UNO plugs?

[The Medway Handyman]

UNO plugs & Quicksilver screws.

[The Other Mike]

You sure the mdf is capable of bending to the radius you require?

Drill much bigger holes in the wall, plug with chopped up section of broom handle liberally smeared with injection resin (the resin is in fixings section of the toolstation and screwfix catalogues) Let it set for a day or so, then use woodscrews. You'll pull the mdf through the screwhead or snap the screw before the plug is pulled out of the wall.

[Tim Watts]

OK - With he block I would be tempted to use the SX type - the teeth do seem to help (I have a couple of block walls, mostly brick). IIRC I did use the S type in my block walls but they are very short walls and no need to pull bends into the skirting.

[Brian Gaff]

I never had much luck with those plugs myself, though ones that had some glue on looked promising. The constant pull on the screw eventually made things fall apart, at least on my wobbly walls it did. Brian

[David]

Perhaps a touch of "Go on! Pull your way out of that one, damn you!"

There is quite a serious bend, though - possibly near the limits of tolerance for the MDF.

I really will post some pictures soon.

[David]

The gap between skirting and wall is from zero to about 15mm so it is already so very nearly there.

Having got the damn thing bent and lined up, I would prefer something more immediate, but if all else fails that could be an option.

More or less how the original skirting was fixed (apart from in this bay where it was hardboard over wood strip with beading along the top).

Which has now prompted me to look at the upstairs bay which is done in short straight runs with angles in between instead of a continuous curve - this is the skirting, wall, and window cill.

Cheers

Dave R

[David]

Uno plugs are the ones which taper out to the top, and also have a significant rim. I already have these.

See "Next up in the Rawlplugs are brown. The strip they attach to says 7mm drill and 4-6mm screws. However the brown wall plugs are more than 7mm across the wide end."

So they don't match the requirement of no taper and rimless. Fischer S (for example) do.

Quicksilver screws have the right sort of profile, but are slot head. As also noted above, I have proper wood screws with slot heads but I don't like slot heads for this application where they need to be pulled in very tight. There is a reason why I have not used slot head screws for years, but prefer cross head screws. I think it is called "cam out" - and one of my requirements is to be able to remove the skirting if I have to get the floor up at any time. If I bugger up the slot putting the screw in then getting it out again may be a problem.

Cheers

Dave R

[Tricky Dicky]

Can you not fix some short noggins of wood the same thickness as the plaste r, at points around the curve of the bay. Then simply screw the skirting to the noggins. I would also kerf the back of the skirting as TMH suggested, it will leave a slight crenelated look to the top edge but some caulking wi ll soon conceal that.

Richard

[David]

I read up on kerfing but what I read was based on removing material from the inside of the curve then glueing to hold the shape.

Noted that removing some material from the back should make the MDF in front of the notches thinner and more bendy.

So, no.

However it is so close without kerfing that I'll have another go at pulling it all in.

By the time I have finished I will probably know a better way to do it if I need to do it again.

Cheers

Dave R

[The Medway Handyman]

??? Not the ones I've been using for years :-)