You can find many types of screws at hardware and speciality screw stores. The majority of hardware screws used today are oval head Phillips. The early years of Fender and Gibson, oval head-slotted screws were used in the majority of instruments. If you are replacing or needing extra screws, it is important to find the same type used to retain the value of your instrument. If you have an old Broadcaster, you don't want to replace the # 4 slotted-wood screws with a # 6 phillips on the pickguard. It's good to make note of all the pickup screws used in your instrument for further reference. If you repair guitars or work on them, I have lost screws in the carpet and need to find another one. It's good to know how to determine what the screw is: Here is a little list to work with.
- Test the material: steel (attracts to a magnetic field), brass, stainless steel
- Type of head (round head, oval head, flat head etc.)
- Measure the length of threaded shaft
- What type of threads: Machine screw thread, wood screw, sheet metal screw, metric thread. Machine screws used # of threads per inch. Wood screws are threaded about 2/3 up the shaft with the rest un-threaded, Sheet metal screws are wood type screws-threaded the full length of the shaft, Metric screws have metric threads.
- Need to determine the plating: Nickel, Chrome, Cad etc.
- You need to measure the screw diameter: use a pair of calipers or a Screw I.D. Gauge. To determine the threads per inch you need a thread gauge. I use a "Gauge for American National-60? Threads" to measure threads per inch.
Keep notes on all the hardware on your instrument as it will come in handy one day. There are many guitars I don't have all the information on and would like to find out from you players and collectors out there. I'll compile all the information for future articles.
Below is the basic diameter of standard american screws.
| Screw size | Screw diameter | Screw size | Screw Diameter |
| # 1 | .073" | # 7 | .164" |
| # 2 | .086" | # 10 | .190" |
| # 3 | .099" | # 12 | .216" |
| # 4 | .112" | 1/4 | .250" |
| # 5 | .125" | 5/16 | .312" |
| # 6 | .138" |
WRITTEN ON JUNE 12, 2015, BY