Replies

1. 
   Bob_Van_Dyke | Oct 08, 2007 05:07pm | #1

   First of all- get yourself a large architects triangle and use that to set 45 degrees- the size of that will magnify any error that you have in the setting- but that is only the beginning- two ways of checking. Make two test cuts at 45 degrees- put them together to form a "corner"- put your square on the outside of the "corner"- if it is not dead on 90 then your setting is off a little- keep checking till it is right on.
   the next way is one of the best because it does not require super accuracy!
   Use the concept of complementary angles. I usually set the saw at 45 degrees. Using longer stock- cut your first cut- the piece on the miter gauge (left of the blade)forms one half of the miter- the "drop" the piece to the right of the blade is the other half of the miter- even if the blade is a little off of 45 it will still come out square.- I have a shop made sled I use for miters (on edge) all the time which uses the same concept.
   Hope that helps- let me know how you make out.
   Bob Van Dyke

1. 
   1948mike | Oct 12, 2007 08:17pm | #2

   I like the complimentary method. Very clever! I did have one of the guys at the machine shop at work make a larger 45 from a piece of aluminum, and that helped considerably. Thanks for your reply.

   Mike

2. 
   gnugs | Dec 12, 2019 09:35pm | #3

   I'm trying to imagine how the complimentary method would work on closing a box so all four miters match. I get the method will produce three matched miters but that last miter worries me. I'd love it to work since I'm having trouble getting that perfect 45 degree setting on the table saw. Any advice would be welcome.

3. 
   _mj_ | Dec 12, 2019 09:52pm | #4

   Using complimentary as BVD suggests all corners WILL be 90s. Last fit will be fiddly, but only for length. Suggestion for the large architect's square: cut off the peaks and you'll have a clearer look at it. The corners draw your eyes and lie to you, you want to judge blade angle up in the flats of the blade. I chopped a plastic framing square for this, it stands on the table as a bonus.

4. 
   fivebirdscustom | Dec 13, 2019 10:05am | #5

   Get one of those 30 dollar digital angle gauge. The little box shaped ones.

   It's one of the best investments I've made recently. Easy to set up tools and really works well at resetting angles. The stop on my saw for 45 is okay, but with the digital gauge, I know it's exact!

   Here's the one I grabbed a few months ago: https://www.amazon.com/gp/product/B07P6ZD8KT/ref=ppx_yo_dt_b_asin_title_o03_s00?ie=UTF8&psc=1

   I've been really happy with it. Zeroing it can be a touch finicky, but we're also looking at really nice accuracy. I like that it can do absolute angles and relative angles.

   For 35+ years, I've been using squares and triangles and never had the same accuracy.

5. 
   geedubbee | Dec 14, 2019 11:25am | #6

   The Beall Tilt-Box is the one that has lasted in my shop. A few dollars more but, great battery life, accuracy and magnet placement for my use.

   A sled can help control small box parts contributing to your accuracy. A dedicated, simple version would be quick to make. I made one per my typical sled design but, I have established a preference. The bells and whistles aren't necessary but, the hold downs are key.