If you’re at the in the drywall section at the hardware store you will notice there are many drywall knives to choose from. There are different sized knives, metal knives, plastic knives ect… In this post we will explain which knives we prefer to use and for what applications we use them for. Please note: many professionals use tools differently throughout the industry, post is simply how WE use them. If you find that using a tool in a different way from us works better for you then use what works best for you!
Metal Vs Plastic
First thing first, 99% of the time we use metal drywall knives. Plastic knives are far cheaper, however they are meant to be disposable and we do not recommend using them. Metal knives are robust and last for years if properly maintained. The only time we ever use plastic drywall knives is when we have to get into a corner with less than 1.5 inch clearance. In that case we cut the plastic knife to size with tin snips, in order to access the tight space. Main point, always buy metal knives!
Blue Steel vs Stainless Steel
Drywall knives are commonly made out of blue steel and stainless steel. Both of these metals are rust proof, however blue steel us more flexible and produces more rust residue when left wet. Some professionals prefer the flexibility of blue steel but the extra maintenance can be cumbersome. Stainless steel on the other hand, is a less flexible metal, however it doesn’t produce the rust residue that blue steel produces. If you are a drywall professional, the debate ends at personal preference. If you are a homeowner or DIYer, you’ll prefer stainless steel blades.
Drywall Knife Sizes
4 Inch
We use 4 inch knives, mainly for flattening paper tape and inside corners, in new construction. We also like using the 4 inch knife for filling small holes and minor patch work.
6 Inch
The 6 inch knife is our most commonly used taping knife. We use it for the first coat of mud both in new construction, filling screw holes and drywall repair jobs. We like using the Wall Pro chrome shine knife because it is easier to clean.
10 Inch
We use the 10 inch knife for coating joints in new construction and the finish coats in drywall repairs. We prefer to use the 10 inch knife over the 12 inch knife in most cases. The 10 inch knife is less strain on the wrist, elbow and shoulder.
12 Inch
Although we prefer to use the 10 inch knife in most cases, we still use the 12 inch quite often. We use the 12 inch drywall knife for finish coats and skim coating. Read about our skim coating process here.
14 Inch
The 14 inch knife is a great knife to have, however we do not use in most of our jobs. We use the 14 inch knife mainly for skim coating drywall and fanning out very bumpy joints.
Conclusion
Drywall knives are not too pricey, individually but the cost adds up when buying multiple sizes so choose wisely. We did not discuss pans in this post but our recommendation is simple, buy a metal pan, not plastic. If you life in Vancouver, WA or the surrounding areas and need some drywall work done, then please get in touch with us by filling out the contact form below. If you would like to learn more about us then check out the NorthWestern Contractors website. Thanks for reading!