Toolipedia: T-Bevel

Toolipedia: Everything you wanted to know about the T-bevel. 


a t-bevel with labeled parts | Construction Pro Tips

What is T-bevel? 

T-bevelsometimes called a false square, can be adjusted, which makes it a handy tool for recording and transferring angles. T-bevels are often used by finish carpenters when installing base trim on two walls that intersect at an unusual angle (non-90-deg. or non-45-deg.) or when installing stair spindles and railings. T-bevels can also be used as a depth gauge. 

Popular Videos

Here are the basic parts of a T-bevel: 

  1. Handle or stock 
  2. Sliding blade 
  3. Thumb wheel or tightening nut 

How is a T-bevel used?  

Operation basics (for base trim): 

  • Loosen the thumb wheel or tightening nut 
  • Slide the T-bevel over the corner with the handle on one wall and the blade on the other 
  • Tighten thumb wheel or tightening nut 
  • Bring the T-bevel to the miter saw cut station 
  • Press the handle against the fence,and adjust the angle of the saw blade so its the same as the angle of the T-bevel blade  
  • Read the gauge on the miter saw and divide that number in half 
  • You now have the angle that each piece of trim should be cut at 

What are the different types of T-bevel? 

  • Standard size blades are 8 or 9 inches, mini T-bevels are usually 4 inches 
  • Handle construction may vary, most are wood, plasticor composite
  • Some expensive models have a built in digital angle meter 
  • Some blades are ruled, often in inches 

What makes a good T-bevel?  

  • The nut needs to hold fast when tightened 
  • Solidly constructed handle 
  • Brass or stainless-steel metal parts  

Johnson company makes high quality T-bevel. 

T-bevel Tip

If you are ever in a pinch for a 45-deg. marking gauge, the sharp end of a T-bevel is just that.    

More finish carpentry tips

Discover other finish carpentry tools  

LeRoy Demarest
I have worked for over a decade as an environmental scientist working on an advanced bioremdiation clean up project. For the past six years I have also worked as an adjunct instructor for several colleges, both F2F and online, teaching a number of science courses. Finally, I have been freelance writing for a variety of publications on the topics of: gardening, environment, construction, science, science education, academics and technical work.