tjbnwi
Member
- Joined
- May 12, 2008
- Messages
- 7,047
Charlie Mac said:Maybe not a good an analogy Tom. Just saying a known accurate square to calibrate the table vs a known squared table to validate a square. And with that I'll stop creating background noise so the OP can get his MFT squared away. [oops]
How do you know the square is accurate? The manufacture told you so? I send all of my calibration out to a calibration lab once a year to be certified. I know my measuring devices are accurate down to 0.0005". Had one company I worked for we had to send our 25' tape measures to the cal lab to be checked.
With the 5 cut method, if you get the rail to fence set where the difference between the two ends of the 5th cut is 0.0005" or less you have a square piece to check your square against. The 5th cut on my MFT is out 0.0000 in just under 24", so I know my MFT is as square as possible. I can check any square against the cut piece. If the square does not align perfectly the square is off, can't be anything else.
I would like to see someone with 4 dogs do a 5 cut to check the accuracy of the hole pattern on the MFT, we all assume it is perfect. A test would be nice to confirm that is the case. I'd do it but I don't own any type of dogs for the MFT.
A simple 5 cut test will identify the problem quickly and allow the OP to begin to make the proper adjustments. By using only the MFT to set itself you have removed the square from the equation.
By the way, I do build from the ridge down. Supporting the roof properly is the most important part of framing layout.
Tom