15

I need to drill a hole through from my living room to my garage to put an ethernet run between them. I can only drill through from the living room in one spot due to the positioning of the electrical box that I want the ethernet cable to emerge at. I have measured where the hole will come out and found it is directly behind my boiler (the boiler is around 2cm from the wall and the wall is brick and plaster). Is just drilling slowly the trick here or is there another method someone can recommend to stop the drill bit from punching a hole in the boiler once it clears the wall? I was thinking of maybe placing something in the gap betweeen the boiler and the wall as a precaution to slow the drill bit down and give me time to stop drilling?

lriley
  • 153
  • 1
  • 8
  • 9
    Absolutely protect the boiler. A sheet of scrap plywood and somebody on that side watching would be my suggestion. – Aloysius Defenestrate Nov 07 '21 at 13:08
  • Thanks! Both of these solutions sound great! – lriley Nov 07 '21 at 13:19
  • 7
    Plywood is a good idea. You will know when you hit it and have plenty of time to stop drilling because a masonry bit won't quickly cut through it. – jay613 Nov 07 '21 at 13:56
  • 2
    Can you run the cable elsewhere? Ceiling cavity, or perhaps just above the boiler ? Future serviceability is important. – Criggie Nov 07 '21 at 22:04
  • 4
    I'd use plate metal and an alert assistant. – Kyle B Nov 07 '21 at 23:20
  • Alternative to "someone watching" could involve a camera of some sort. – WernerCD Nov 08 '21 at 00:35
  • 2
    Cat5s have a bend radius of 1 inch. You'll want to install something so you don't end up with a tighter bend that untwists all your twisted pair right next to a boiler (high energy device). – Nelson Nov 08 '21 at 03:30
  • @WernerCD it could, but beware - DroidCam is one example of an easy way to do this (view on laptop/tablet, use phone as camera) but I've found it can have quite a time delay, even over a second. I tried it for cutting the back of my own hair during lockdown – Chris H Nov 08 '21 at 13:45
  • @ChrisH yeah, I assume there are options that have real time results - or close enough. Any alternative would need to be metered to match that (IE: 1 second delay = going very slow) – WernerCD Nov 08 '21 at 16:35
  • @WernerCD Plenty of options, like a webcam on a long cable, but as Droidcam is so easy I thought it was worth warning against. Part of the issue is that the delay seemed to increase, so giving a false sense of security – Chris H Nov 08 '21 at 16:37
  • You mention wanting the ethernet cable to emerge at an electrical box, I assume that this is not a currently in use electrical box for line voltage, as it would be against code to run ethernet into such a box. – Glen Yates Nov 08 '21 at 18:19
  • @GlenYates Not strictly - there are correct ways to run communication cable into an energized enclosure. I've got CAT5E inside 600VAC/1600A switchgear, for example - it just needs to be cable with the correct rating and installed by the rules. It's not strictly disallowed. – J... Nov 08 '21 at 18:54
  • Truly, the only part of the wall that overlaps between your living room and your garage is entirely occupied by a boiler? That's a small wall, big boiler or some problem with the measurement, surely.. ? – Caius Jard Nov 08 '21 at 19:02

3 Answers3

44

Buy a drill stop to screw onto your bit, and set it to the thickness of the wall. Some drills also have a built-in stop that can be adjusted. If you don't know the thickness of the wall, then just increase the depth each pass.

Evil Elf
  • 3,809
  • 8
  • 47
  • 59
  • 6
    This. But first set it a bit under the expected thickness of the wall. You don't want to find out wall was actually thinner at this point by hitting the boiler. – Mołot Nov 08 '21 at 10:34
  • 4
    You can also make a single-use stop by wrapping tape around the drill bit, with the edge of the tape at the depth you want to stop drilling. When the tape reaches the wall, stop. I wouldn't use tape by itself to stop me from drilling into a boiler though. – Dan C Nov 08 '21 at 18:51
  • Definitely a good tip but I'd still put something on the other-side of the wall as a safety net. Last thing you want is to find your measurements were a little off and your boiler is suffering for it. – Lio Elbammalf Nov 10 '21 at 16:29
25

Don't. You'll ruin the cable.

As Nelson points out in the comments, CAT5 cables have a turning radius of 1 inch to avoid damage to the cable. In a scenario where the boiler is only 2cm from the wall, achieving this bending radius will be difficult, if not outright impossible. Additionally, the heat from the boiler is also likely to damage the cable if it's held at such close confines to it.

As such, it's highly likely that going through with this wiring scheme will damage the cable, so you should reconsider your plans and possibly drill the hole through the wall somewhere else.

nick012000
  • 706
  • 6
  • 10
  • 8
    The easiest fix is to drill at an angle, and then perhaps chisel out a bit of a ramp leading into the hole to accomodate a nice smooth turn. With some luck, drilling at an angle can also let you avoid the boiler altoghether. You'll need a long bit, but those are readily available. – TooTea Nov 08 '21 at 08:11
  • @TooTea Or run the cable through the inside of the wall, or run it through a conduit along the living room side of the wall. – nick012000 Nov 08 '21 at 08:17
  • 19
    Heat from the boiler? Every boiler I have touched in my life was so well isolated that I could barely tell a difference from the environment. – MaxD Nov 08 '21 at 09:09
  • 6
    @MaxD Sounds like you spent your life around modern high-efficiency condensing gas units. Traditional non-condensing boilers (gas, oil, wood, coal, …) emit a whole lot of waste heat in my experience. – TooTea Nov 08 '21 at 09:40
  • 12
    Bending it just once (not flexing back and forth) and running at 100Mbit, CAT5 will handle far tighter bends unless you're very unlucky, i.e. it's highly unlikely that going through with this wiring scheme will damage the cable. An old, badly-insulated boiler is more likely to have an effect, but even my previous one (from 1996) would have been fine with CAT5 touching the outside for long periods. – Chris H Nov 08 '21 at 11:02
  • If you want to look super-professional, you could install some conduit on the boiler side, complete with an elbow at the hole. This would both reduce the bend in the cable and add some protection against heat/moisture (maybe not just from the boiler, but from just being in a garage in general, depending on the climate where you live). And it would also make it easier to upgrade to CAT6/7/8 or fiber in the future. – Darrel Hoffman Nov 08 '21 at 14:38
  • @DarrelHoffman Would you really be able to fit that conduit into a space less than an inch across, though? I imagine that'd make it difficult to use a hammer or stapler or whatever the appropriate tool is for that particular brand of conduit to affix the conduit to the wall. – nick012000 Nov 08 '21 at 14:56
  • It could probably fit - without seeing the site or at least a picture it's hard to tell. Though you might not be able to affix the part behind the boiler, presumably most of the conduit would not be behind the boiler, and you could affix that part no problem. So long as you get 2-3 clamps or whatever on it, it's okay for the end behind the boiler to be loose (since the boiler itself will likely pin it down on that end anyhow). – Darrel Hoffman Nov 08 '21 at 15:01
  • 2
    +1 But I'd stop short of don't - the boiler may not even get that hot on the outside, and even if it does there are suitable cables for this type of application, OP just needs to make sure they get the right type. CAT5/6 cable comes in all type of industrial grades for high voltage environments and high temperature. It's all in the ratings. – J... Nov 08 '21 at 18:22
  • 12
    In my experience, that "1 inch turning radius" sounds highly conservative. CAT5 isn't fiber, and in practice you could probably tie an overhand knot in an average CAT5 cable and yank it tight and it wouldn't be any worse for it. (Well, except for having an annoying knot in the cable, that is.) As for heat, +60 °C (which any CAT5 cable must tolerate) is a decent temperature for a sauna. If the exterior of your boiler gets that hot, you'll know it when you stand next to it (and should probably consider getting a better insulated one to save on heating costs, at least during summer). – Ilmari Karonen Nov 08 '21 at 20:51
  • 1
    Cat5 cables are so cheap that this is not a real concern. Worst case they replace it once in a while, its not a big deal. – JonathanReez Nov 09 '21 at 07:21
  • 1
    @JonathanReez The cable might be cheap, but damage to the cable might mean its performance degrades and data gets lost. Even relatively small amounts of damage to the cable can cause speeds to degrade from 1Gb/s to 100Mb/s. – nick012000 Nov 09 '21 at 07:28
  • 1
    ... that's pretty easy to detect, letting OP know its time to replace the cable. Not a big deal. – JonathanReez Nov 09 '21 at 07:38
0

Get a drill with a depth limiting adjusterenter image description here

Mike Mackenzie
  • 17
  • 2
  • Note there where it says "Images may be subject to copyright"? Please post the source for your image, but don't use it if it's copyrighted - that violates SE policy. Also, this adds nothing to the highly up voted, already accepted answer. – FreeMan Nov 18 '21 at 13:27