TIPS on SCREWS AND SCREWING
We’d like to share a few tips about screws and screwing. We routinely come across the same issues with screws and their holes. Many of these issues are caused by user error. Here are some of the most common issues and how to avoid or fix them:
Stripped heads
If you service your guitar regularly, you’ll need a selection of screwdriver types: Phillips and flathead, and most commonly Phillips sizes #0, #1 and #2, and flathead sizes including 1/8” and 1/4″.
The most important point here is to always use the right size screwdriver for the screw you are driving. If you don’t, it will slip and damage the screw head. If the slots on the screw get too damaged, you won’t be able to turn or remove the screw at all.
There is another reason to avoid using the wrong sized screwdriver. It’s all too easy for it to slip off the screw as you apply pressure to it. If this happens, there’s a good chance you’ll damage the body of your guitar.
Stripped screw holes
If a screw is just turning in its hole, then the hole has become too wide for the screw. This can happen with strap pin screws, especially the one at the bottom of the body. Don’t just use a larger screw – you’ll only make the problem worse.
The best solution is to plug the hole and re-drill it. In some cases, a little heat and moisture can be used to expand the wood fibres in the hole, resulting in a tighter fit. This is fiddly to do and not a long-term fix. If it’s a strap pin that has this problem, definitely do the job properly. Avoid the hacks you read about on guitar forums! This screw is holding the weight of the guitar and needs to be secure.
Bear in mind that not all manufacturers use screws of the same size. The screws on cavity covers and pickguards, for example, differ in size on Fenders (larger) and Gibsons (smaller). Always replace like with like.
Wonky screws
Screws should be driven in at a right angle to the surface so that they are evenly seated once in place. If you repeatedly drive screws in at an angle, eventually the screw hole will assume that same orientation and you’ll end up with wonky screws like the one in the picture. It doesn’t affect the playability of the guitar. But it won’t look great and can spoil the look of an otherwise beautiful instrument.
As with stripped screw holes, the best solution is to plug the hole and re-drill it. Trying to ‘straighten’ the existing hole tends not to work well because the drill bit wants to follow the existing path. When re-drilling the hole, make sure it’s perpendicular to the surface of the guitar. Use a drill press if you have one, or a try square to ensure that your drill bit is perpendicular. Use a brad point drill bit.
Overtightening machinehead screws
We’ve had to extract several machinehead screws from headstocks because the screw head has snapped off. These small screws in particular are delicate and need to be treated with care.
When installing a new set of tuners, and assuming they have screws (not all do), tighten the screw on the rear about 80%-90% of the way in but do not fully tighten it. Add and tighten the nut and bushing on the front of the headstock. Then drive in the screw the rest of the way. Do not overtighten it – once it bottoms out and you encounter resistance, stop.
If you fully tighten the screw on the rear before fitting the nut and bushing, tightening the latter can cause some movement to the machinehead. This exerts undue pressure on the screw head. It will eventually weaken it increasing the risk of it snapping off.
Cracked cavity covers
Most of us have experienced cavity covers or pickguards that crack close to the edge where a screw hole is. This can be avoided with the right technique.
There are two common causes. One is overtightening the screw. This ‘pinches’ the plastic and, over time, causes it to split. When re-attaching a pickguard or a cavity cover, once the screw is bottomed out in its hole and you feel resistance, stop. You don’t need to strangle the life out of it.
Another cause is that one screw is fully tightened first, before the others are driven in place. The problem here is that sometimes not all the holes in the cavity cover (this also applies to pickguards) perfectly align with the holes in the body. In such cases, the cover needs to be positioned so that any misalignment is ‘averaged out’ across all the holes. If you screw it perfectly in place in one hole, some others are less well aligned. This means that when you drive those screws, they stretch the cavity cover and exert pressure at its weakest point – that thin strip between the hole and the edge.
The best way to reattach a pickguard or cavity cover is to first get all the screws in position but each one only driven about 80% of the way in. Then gently lower each screw a further 10% or so, before driving them in the remaining distance until they are all fully seated. This allows the pickguard or cavity cover to settle in its optimum position relative to all the screw holes beneath.
And finally…
Rubbing a screw against some candle wax, a dry bar of soap or other dry lubricant will help it drive into its hole much more easily and without that horrible ‘creaking’ sound. No need to overdo it, a little bit on the thread of the screw is enough (just twist the screw between your fingers against the wax). Avoid wet lubricant, like Vaseline, as water swells the wood and can make the hole too tight.
GUITAR NOT FEELING LIKE IT SHOULD?
A professional setup will almost certainly help.
Contact us to book your guitar in for the attention it deserves.