Pilot Holes for 120mm nails

Discussion in 'Carpenters' Talk' started by Marie_j, Apr 5, 2013.

  1. Marie_j

    Marie_j Member

    Having laid my concrete blocks I am now ready to assemble my wooden base for my new garage.  The instructions say to pre drill pilot hole to take the 120mm wire nails.  Can anyone advise thge size of hole required for a 120mm wire nail. 
    Marie x
  2. What diameter are the nails? Around, ooh, 6mm? Are they plain? Or serrated? Plain steel? Or galvanised?

    Either way, I don't know.
  3. What size are the timbers? 3x2? 4x2?

    I can see them perhaps wanting pilot holes if it's being nailed close to the cut end, but usually them nails are just hammered in - espewcially if they're going into the body of the timber well away from the edges or ends.

    I'd have thought.

    I'd say, tho', that roughly a 3mm-ish hole would be a reasonable pilot for a 6mm nail - tight enough so's it still grips, but large enough to prevent splitting.

    But that's just a guess.
  4. Marie_j

    Marie_j Member

    Thanks for the reply.  I have lost my drill hole guage.  I drilled a 4mm hole and the nail passed through it with a little effort so I think the nail is 4mm.  It is plain with a small serratted section.  The bearers are 70mm and 35mm.  Some of the 70mm bearers are in fact two 35mm bearers nailed together.  The instructions suggest pr drilling the holes for the nails to make it easier to nail together. Would it be wise to pre drill pilot holes in both parts of wood or just through the first section?  I think I will practise on some scrap wood first to get the size right.
  5. Mr. Handyandy

    Mr. Handyandy Screwfix Select

    Does it state 'pilot' or 'clearance' ?

    Clearance is for a nail/screw to pass through the piece being attached, and pilot is for the nail/screw to grip the piece being fixed into, without forcing the wood apart.

    A rough guide is for the clearance to allow you to push a nail/screw in somewhat(but not fall in. And for the pilot approx half the diameter of the nail/screw(actual for a screw, is the diameter of the shaft as if it had no threads)

    Mr. HandyAndy - Really
  6. Marie_j

    Marie_j Member

    The instructions are very basic.  It just states to nail together the two pieces of wood, " this may be easier if the holes are pre-drilled".  The  wood makes up a frame which a log cabin will be built on, so it needs to be nailed together square, level and strong.  After reading your reply i think I will just drill a partial clearance hole in the first piece of wood.
  7. I think you're on the right lines there, Marie. If the nail is barely more than 4mm diameter, it won't be that resistant to bending, so a pilot hole in the first piece of timber - as you say - might very well be a good idea. 3mm should be fine. It's best if the nail bites to a fair degree in the first layer, and fully in the second piece - so no hole there.

    If there's lots of nailing to do - and I bet there is - by all means bash away without any pilots to see how it goes. As long as the nails are a few inches from the ends it shouldn't split the timber.

    Not sure what you mean by 70mm and 35mm; timber has 2 dimensions, so what's the other? 35mm is pretty small, so perhaps there is a risk of splitting...
  8. Marie_j

    Marie_j Member

    The company supplied 35 x 75mm, 75 x 75 mm and then to save money I guess two 35 x 75mm nailed together.  I was also woried about splitting the 35mm wood.  They have cut corners to save money which is really annoying as the garage was not cheap to buy.
  9. jeznotts

    jeznotts Member

    nice one da! i was just about to explode with "wtf' with peoples bad understanding of the whole pilot , nail thing! phew!
  10. Marie_j

    Marie_j Member

    I need to find my 3mm drill bit as nails were bending today.  I put them in with a short 4mm hole to hold them in place to start them off.
  11. Mr. Handyandy

    Mr. Handyandy Screwfix Select

    Get the hole ALL the way through the piece of wood you are fixing. Hit hard and straight, don't tap.

    Make sure your hammer-head is not rounded.

    Mr. HandyAndy - Really
  12. Marie_j

    Marie_j Member

    Thanks, I am using a claw hammer.

  13. Anyways, what Mr Ha meant was, make sure the striking surface of your hammer is nice an' flat, not rounded thro' use (I think).

    (Jez, I think Mr Ha's explanation of 'pilot' etc was pretty spot on? But ta anyways )

    Marie, your timbers aren't huge, especially in the 'thickness' department - around 1.5" or less. Pretty good chance the ends will split if nailed too close. As Mr Ha says, find your 3mm drill and drill all the way through the first layer. By the time you've then hammered the nail through this layer - which should now be easy - the nail should really be held so securely that - cough - you'd have to be a wee bitty - er - ham-fisted to bend the nails from then on... ;)

    Hammering ain't easy, y'know. If you haven't done much before, then you are going to have a steep learning curve.

    Hold the hammer where it should be held - near the end away from the head. You might find it tempting to hold it much further up - it might feel more 'steady' - but it won't serve you as well. Then you swing mostly from the elbow, not just by rocking your wrist. If you look at the hammer head, if you 'swing' from the wrist, the head will describe quite a tight arc in the air, so will be hitting the nail head with an angled blow. From the elbow, this arc is much larger. Position your arm so's the hammer hits the nail head straight on, which means you begin your swing partly to the side.

    Oh, and one more important thing - confidence. Just bludy go for it. Get into a 'swing'. Whap! Whap! Wha-btoiinnnggggg (straighten straighten straighten...) Whap!

    You'll soon be knocking the nail all the way through with - ooh - 4 blows. And one to finish.
  14. Marie_j

    Marie_j Member

    Thanks, that all makes sense, I will start again in the morning and hopefully get more that two the today's tally of two nails!
  15. Marie_j

    Marie_j Member

    I found my guage, the 120mm nails are 4.2mm.  My 3mm wood drill is too short to go all the way through the wood.  I am off to the diy shop to look for a long drill bit, failing that I have some 125mm  thicker nails which i might try using.
  16. Mr. Handyandy

    Mr. Handyandy Screwfix Select

    Use a 4mm drill-bit for the clearance hole. And it will be long enough.

    Mr. HandyAndy - Really
  17. Marie_j

    Marie_j Member

    No extra long 3mm drill bits available. Screwfix do sell 120mm screws which now seem an easier option especially for the 35mm half bearers.  I will also use the 4mm as advised by Andy.
  18. was dunc before

    was dunc before New Member

    Its quite important the bearing frame is substantial enough to support your garage. What you were given sounds flimsy and cheap.  I would make it out of 4x2 treated and use screws to put it together. Or timberdeck screws which work quite well with framing.  Its only another inch off the blocks, but an overall improvement in structural integrity.
  19. Jeepers, this is getting complicated!

    Even if the 3mm drill doesn't go all the way through, it must go most of the way? In which case, that's far enough - hammer the b...

    Screws are a good option, but you need a power drill/driver or else you'll never do it. Does your drill have the option - low speed, low gear - to drive 5" screws?!

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