Quick Method to Mark and Cut out a Hex Tool for Hydraulic Cylinder Repair
Channel: HYDRAULIC.ONLINE GOLD COAST
Date: 2021-05-27

When Breaking out Hydraulic Cylinders we usually need to make tools of different sizes (Hex Plates) to Loosen Very Tight Piston Nuts in our breakout bench.  

How Tight you ask?  We have used up to 30,000 Nm (22,000 foot-pound) to undo some piston nuts on the end of a Cylinder's chrome rod. 

Our Hydraulic "torque tube" Cylinder Breakout Bench has the capability to generate up to 60,000 Nm or (44,000 foot-pound) of torque.  

I this video I show our Apprentice Seth, how to quickly, easily and quite accurately mark out and then cut out a Six (6) sided hole or Hex in a piece of steel Plate to fit large tight piston nuts.

0:00 Intro and why we have to sometimes make custom tooling to loosen tight Hex Nuts.
1:05 The two (2) most Important measurements
1:57 Why we need a Hex cut into this plate.
2:25 Example 1 (already marked out)  
3:05 Get a Rule, Metal Scribe and Dividers
3:35 Take half the Diameter (90mm) of the Diagonal (=45mm) 
4:10 Scribe with dividers a 90 mm diameter circle
4:30 Draw a clear line through the exact centre of the circle
5.20 Check the circle diameter is correct and that your dividers are at 1/2 diameter
5:50 Mark out your Arc Start points with a centre punch 
6:05 Mark out your Arcs
6:30 Joining the Arcs with a straight line.
7:35 Checking dimension across the flats 
8:00 Double check the actual nut before cutting
9:05 Cutting out the Hex with a 4" Angle Grinder using thin cutting discs. 
9:55 Plate with Cut Hex mounted to our Hydraulic Cylinder Breakout Bench
10:40 Rod and Piston Nut assembly mounted in Breakout bench.