Onoff Posted April 2, 2017 Author Posted April 2, 2017 (edited) I thought you really risked jacking if you don't pilot the board to CLEAR THE screw i.e the actual outside diameter of the threads. Just drilling a pilot the shank size still risks jacking IMHO. EDIT: I can alternate between stainless and Knauf screws if it keeps the peace! Edited April 2, 2017 by Onoff
Nickfromwales Posted April 2, 2017 Posted April 2, 2017 Yup. That's what I'm getting at. Clear the threads and its bingo bango.
Onoff Posted April 2, 2017 Author Posted April 2, 2017 On 02/04/2017 at 22:22, Nickfromwales said: Yup. That's what I'm getting at. Clear the threads and its bingo bango. Expand I was taught woodwork at school when there was none of this new fangled self cutting stuff screw wise. Everything had a plain shank which required a clearance hole. Slotted was the norm and a Phillips head was considered exotic. Always wary of "needs no pilot". 1
Onoff Posted April 3, 2017 Author Posted April 3, 2017 The 39mm Knauf DIY Maxi Screws put in with the Makita and sunk just under flush into a test piece of Aquapanel - no pilot: 1
Nickfromwales Posted April 3, 2017 Posted April 3, 2017 Best to add that it's all to do with installer competence at the end of the day. Thats the 6th sense when one knows that a screw has gone in far enough and the board has firmed up against the timber. Many people assume that a tight screw is good enough, but it may still have to go a bit 'more' to send it fully home. PB screws are an extremely bad choice for this job as they're fully threaded, so are considerably more likely to promote jacking, but worse still they are very thin and extremely brittle so tend to snap very easily when more torque is applied than they're meant to accept. They're designed for soft plasterboard not rock hard backer boards . They'll snap even if you just accidentally drive them into a large knot so to use them for this application has, imo, been done out of laziness and / or penny-pinching.
Nickfromwales Posted April 3, 2017 Posted April 3, 2017 On 03/04/2017 at 15:39, Onoff said: The 39mm Knauf DIY Maxi Screws put in with the Makita and sunk just under flush into a test piece of Aquapanel - no pilot: Expand Seem to have set in pretty well. What's your gut feeling? The stuff is just too brittle for my liking so I'll be sticking with PB.
Onoff Posted April 3, 2017 Author Posted April 3, 2017 (edited) These Knauf screws do seem rather "tough" tba. Go in with very little spoil generated as the ribs countersink the board. I just took the screws out and there was no "lift" of the board as it backed out. Hardly any breakout at the back and a clean hole bored with no pilot. Each screw has Aquapanel precisely engraved on the head and they are reassuringly expensive! Where the wc is going is just one Aquapanel where the red line is. Blue centre lines of where I can get fixings: Edited April 3, 2017 by Onoff
Construction Channel Posted April 3, 2017 Posted April 3, 2017 has anyone tried them in hardi backer? I assumed it was similar stuff but looking at those pictures they look more like Wedi board??
jack Posted April 3, 2017 Posted April 3, 2017 Fermacell similarly recommends not using drywall screws. Guess what the same guys who did our bathrooms used on the Fermacell?
Construction Channel Posted April 3, 2017 Posted April 3, 2017 On 03/04/2017 at 19:37, jack said: Guess what the same guys who did our bathrooms used on the Fermacell? Expand 50mm ring shanks?? 1
Onoff Posted April 3, 2017 Author Posted April 3, 2017 On 03/04/2017 at 19:37, jack said: Fermacell similarly recommends not using drywall screws. Guess what the same guys who did our bathrooms used on the Fermacell? Expand
Nickfromwales Posted April 3, 2017 Posted April 3, 2017 On 03/04/2017 at 19:37, jack said: Fermacell similarly recommends not using drywall screws. Guess what the same guys who did our bathrooms used on the Fermacell? Expand Still better than the risks associated with buying a taylor wimpey home, even if they do now 'boast' "quality insulation" and "water saving boilers". Wtf . @jack, are these issues currently only in the bathrooms? Edit : oops, wrong thread to ask. I'll just nip next door to jacks house
jack Posted April 4, 2017 Posted April 4, 2017 On 03/04/2017 at 21:45, Nickfromwales said: @jack, are these issues currently only in the bathrooms? Edit : oops, wrong thread to ask. I'll just nip next door to jacks house Expand @Nickfromwales, you're not the only one to have confused the two threads I think!
Nickfromwales Posted April 4, 2017 Posted April 4, 2017 On 04/04/2017 at 08:10, jack said: @Nickfromwales, you're not the only one to have confused the two threads I think! Expand It's Clive's fault for selfishly worrying about his own bathroom
jack Posted April 4, 2017 Posted April 4, 2017 I should add, anyone whose thread about his bathroom extends to 27 pages isn't really in a position to complain about occasional off-topic detours! 1
Onoff Posted April 4, 2017 Author Posted April 4, 2017 That's a very...bouncy...video... Anyway, back on track: Despite my best efforts some of the timber faces that the Aquapanel will go on are a little low. I can slip in a (yellow) 1mm shim here and there. I could set the plane and glue 1mm thick strips of timber on to get a continuous pack. I'm thinking it'd be better just to put the board on with lines of Sikaflex on the timber but don't screw to the low areas until the Sikaflex has gone off. That way it will have dried as a continuous pack?
Onoff Posted April 4, 2017 Author Posted April 4, 2017 On 04/04/2017 at 08:44, jack said: I should add, anyone whose thread about his bathroom extends to 27 pages isn't really in a position to complain about occasional off-topic detours! Expand Does that include pages on the old forum? I'm feeling your pain btw with all your grief. People's definitions of "quality" vary so much and I'm sure to many trades it's just a job. I'm guessing though you've at least a nice warm, draught free shell within where you can fix it all!
PeterW Posted April 4, 2017 Posted April 4, 2017 On 04/04/2017 at 08:45, Onoff said: I could set the plane and glue 1mm thick strips of timber on to get a continuous pack. I'm thinking it'd be better just to put the board on with lines of Sikaflex on the timber but don't screw to the low areas until the Sikaflex has gone off. That way it will have dried as a continuous pack? Expand Seriously.... Sikaflex, screw it on and be done with it ! You cannot see a 1mm deflection in a backing board, from memory they are made to 0.5mm tolerance anyway so it may not be 1mm.... 2
jack Posted April 4, 2017 Posted April 4, 2017 On 04/04/2017 at 08:49, Onoff said: I'm feeling your pain btw with all your grief. People's definitions of "quality" vary so much and I'm sure to many trades it's just a job. I'm guessing though you've at least a nice warm, draught free shell within where you can fix it all! Expand Yes, definitely warm and draft free now all the roof leaks have been fixed! #firstworldproblems
Onoff Posted April 4, 2017 Author Posted April 4, 2017 (edited) Next question..... I need, very shortly to drill a hole in the top (?) of the cistern and run a pipe up into the loft. This, for an "odour" take off pipe alluded to elsewhere. Easiest for me would be a bit of 20mm flexible conduit and an M20 stuffing gland siliconed in. Sound about right? Edited April 4, 2017 by Onoff
Onoff Posted April 4, 2017 Author Posted April 4, 2017 On 04/04/2017 at 09:02, jack said: #firstworldproblems Expand Oh yeah, and my dormer leaks in all 4 corners and elsewhere. Swap you?
jack Posted April 4, 2017 Posted April 4, 2017 On 04/04/2017 at 09:05, Onoff said: Swap you? Expand Finish the bathroom first and we can talk!
Onoff Posted April 4, 2017 Author Posted April 4, 2017 On 04/04/2017 at 09:06, jack said: Finish the bathroom first and we can talk! Expand I'll throw in the wife's recipe for lemon ice cream! Negotiations #Not The Nine O'clock News style!
jack Posted April 4, 2017 Posted April 4, 2017 On 04/04/2017 at 09:39, Onoff said: Negotiations #Not The Nine O'clock News style! Expand Throw in Gibraltar and it's a deal! 1
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