amateurandy Posted August 9, 2007 Author Share Posted August 9, 2007 your now asking this contact to operate through the plastic reducing the magnets overall effectiveness Highly unlikely Arthur; why do you think the standard mountings are made of plastic? The distance obviously is a factor, which is why I used a Heavy Duty magnet. And the door is on chime so we'd probably get some warning if it did weaken. It's interesting to see all the opinions and comments come out at last though for such a simple job... Obviously time is money, so a commercial job would be done differently. And no, I didn't have the opportunity to drill holes before the frame was fitted, though I reckon by going in carefully from 2 directions and joining up and "fishing" I could have totally hidden it. But I agreed with someone's advice that the sensor was best fully protected from the weather i.e. not between the seals. And as for the silicone, my thick arthritic fingers tried to make it neater and failed. But remember that's an enlarged close-up taken with flash. In practice you really don't notice it. Link to comment Share on other sites More sharing options...
arfur mo Posted August 9, 2007 Share Posted August 9, 2007 dont need pictures as i have an active imagination you need to be drilling downwards to hid a cable - look at andys door and explain how you drill from above into the frame to meet the hole you drilled from behind the contact ? only way youll do it is if you can see the outside top of the door and it dont happen unless the doors laid down on its side Angus ( ive been doing em years too remember) so how do i exsplain this for you to be able to understand me and learn ? ok, the contact is going to be hidden when the door is closed the way i do it, so i drill from behind the contact position upwards at appx 45 degree's (towards the cable side of the frame) but aim to miss the plastic surround, means changing to a long masonry tip to get into the mortar/concrete, or long steel tip to puncture the metal lintels depends which type your up against. then i drill again upwards at appx 45 degrees to meet the original drill hole again from the cabled side forming an inverted 'V' effectively. push looped piano wire in from contact side, push striped back cable in from second drilling, withdraw loop snagging cable - eazy peazy and usually you can't see a thing when done, if you blend in the feed cable up the frame with some mastic or mange to slip it behind the filler plate. regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
arfur mo Posted August 9, 2007 Share Posted August 9, 2007 Highly unlikely Arthur; why do you think the standard mountings are made of plastic?The distance obviously is a factor, which is why I used a Heavy Duty magnet. And the door is on chime so we'd probably get some warning if it did weaken. 37 years in the alarm trade a lot of it on service and fault finding at ungodly hours tell's me a little bit differently, i always build out any chance of avoidable faults, learning from the cause's i've seen. as a 'one off' on you own home it's fine, but when it's for a fixed price and on a warranty meaning return calls are at you own cost, especially on the far side of London to where you live, the care taken against the slightest risk naturally rises very steeply. using the wet finger when smoothing silicon was a simple 'trade tip' something i was shown by a double glazing installer many moons ago, you can use a wet sponge for longer runs and which is also great for grouting tile's. regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
Guest anguscanplay Posted August 9, 2007 Share Posted August 9, 2007 so how do i exsplain this for you to be able to understand me and learn ?ok, the contact is going to be hidden when the door is closed the way i do it, so i drill from behind the contact position upwards at appx 45 degree's (towards the cable side of the frame) but aim to miss the plastic surround, means changing to a long masonry tip to get into the mortar/concrete, or long steel tip to puncture the metal lintels depends which type your up against. then i drill again upwards at appx 45 degrees to meet the original drill hole again from the cabled side forming an inverted 'V' effectively. push looped piano wire in from contact side, push striped back cable in from second drilling, withdraw loop snagging cable - eazy peazy and usually you can't see a thing when done, if you blend in the feed cable up the frame with some mastic or mange to slip it behind the filler plate. regs alan see now that makes sense - apart from actually going to all that effort -fishing through a galvanised steel lintel to hid a couple of cm`s of cable to a plainly obviously there surface contact Andy`s would have looked better imo if he had just looped the cable in rather than trying to " disguise " it and where do you buy these magic magnets that loose power due to the plastic ? - could do with some of them to generate callouts on non service jobs lol Link to comment Share on other sites More sharing options...
amateurandy Posted August 9, 2007 Author Share Posted August 9, 2007 Andy`s would have looked better imo if he had just looped the cable in rather than trying to " disguise " itand where do you buy these magic magnets that loose power due to the plastic ? - could do with some of them to generate callouts on non service jobs lol ??? What do you mean, loop in? Agree (as a scientist) re magnets and plastic. I think Arfur needs some teknikul educayshun! Link to comment Share on other sites More sharing options...
Guest anguscanplay Posted August 9, 2007 Share Posted August 9, 2007 ??? What do you mean, loop in?Agree (as a scientist) re magnets and plastic. I think Arfur needs some teknikul educayshun! i`ll post you a piccy tommorrow , not calling your work ( unlike some ) just imo sometimes looks worse for been cammo`d Link to comment Share on other sites More sharing options...
amateurandy Posted August 10, 2007 Author Share Posted August 10, 2007 i`ll post you a piccy tommorrow , not calling your work ( unlike some ) just imo sometimes looks worse for been cammo`d I wait with interest.................. The silicone by the way was primarily there to secure the short cable run to the frame, not to hide it. Link to comment Share on other sites More sharing options...
arfur mo Posted August 10, 2007 Share Posted August 10, 2007 see now that makes sense - apart from actually going to all that effort -fishing through a galvanised steel lintel to hid a couple of cm`s of cable to a plainly obviously there surface contact Andy`s would have looked better imo if he had just looped the cable in rather than trying to " disguise " it and where do you buy these magic magnets that loose power due to the plastic ? - could do with some of them to generate callouts on non service jobs lol agreed it's a surface contact, but you could also use a concealled one if you have the room. with my method you only ever see the contact while the door is open, the magnet and contact are in the ideal position i.e. close as without fouling each other and inline, it looks like part of the moulding to the untrained eye, and you don't see any cable so a professional finish is obtained (the minimum to aim at imo). so it's what i take the trouble to do in domestics or prestige front doors on an office block or instance - but then we all have our versions and levels of "standards" (don't we Angus ). magnets will retain their flux better when kept with other magnets (they are very social beings), as happens when placed in a bag of 50/100 and held on a shelf in storage. all permanent magnets lose some of their power after being made over time, but more sharply so in the period after being isolated i.e. when 1st installed, they also lose some power when dropped as can happen in transporting them. so from the above, a contact working today especially over an extended gap and through other masking properties of the door construction, may (or may not) cause intermittent operation due to this loss, and if on the limits and the door drops slightly due to mechanical wear problems will also be experienced. edit to add if the door slams this will also slightly affect the magnets powers every time which could be enough over time to cause a failure phew! believe me or not up to you guys and galls, but i never thought i'd ever give a master class on door contacts, practical and theory so Andy you owe me pint regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
arfur mo Posted August 10, 2007 Share Posted August 10, 2007 ??? What do you mean, loop in?Agree (as a scientist) re magnets and plastic. I think Arfur needs some teknikul educayshun! well as a scientist that you are, try this -: make a simple jig with a magnet and reed allowing you to move the reed towards the magnet to the point the reed will close, mark the position. now do the same with some plastic sections to imitate the door structure and note the difference. magnetism will pass through plastic but is also reduced by it - scientific fact! regs alan If you think education is difficult, try being stupid!!!! Link to comment Share on other sites More sharing options...
amateurandy Posted August 10, 2007 Author Share Posted August 10, 2007 magnetism will pass through plastic but is also reduced by it - scientific fact! To quote a paper from the University of Surrey: "The permeability of a vacuum has a finite value - about 1.257 Link to comment Share on other sites More sharing options...
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