Makita shear feeler gauge thickness

[Captain K]

I got a used Makita JS1601 sheet metal shear. I didn’t get the thickness gauge 762013-6 to set blades. In the pictures it shows 0.5,1,1.5. Does anyone know if that’s the thickness in mm or is it the metal thickness for that setting? Can someone measure them and post it here?

thanks

[Noitoen]

I think that it's the setting for the thickness of cut. It doesn't make sense to set a 1,5mm gap to cut 1,3 mm sheet.

https://www.icmsmakita.eu/cms/custom/es/user_manual/JS1601.pdf

[EddyCurr]

I agree with Noitoen. The 0.5, 1.0 and 1.5 figures on the tool are reference values for material thickness, they are not the actual clearance values for the three material thickness examples given in the Operator Manual.

I have a few DeWalt and Milwaukee handheld shearing tools. Their manuals are not convenient to me at the moment, but I will offer the following.

IMO, the general principals of shear blade clearance are applicable. Consideration is given for type and thickness of material.

When a blade mfr's recommendation is not known, one rule of thumb for mild steel calls for 7% clearance: 1mm material = 0.07mm clearance. Another recommendation offers similar advice: 0.06mm clearance for each 1mm thickness up to 10mm mild steel.

If upon making a test cut, the resulting edge is unsatisfactory, increase or decrease clearance and test again. Reducing clearance results in a "wiped" appearance (burnished) along the edge and increases cutting effort. Increasing clearance results in deformation along the edge (bent) and reduces cutting effort. If cutting material of higher tensile strength than mild steel, widen clearance - do not overload tool.

Use search terms like "shear blade clearance" & "sheet metal shear blade clearance" for futher research. A few references I turned to to refresh my memory about clearance values:

"https://shear-blades.com"

"www.gasparini.com/en/blog/get-rid-shearing-defects-in-four-steps/"

[Captain K]

I'll give that 7% a try. Thanks to both of you.

[Doozer]

I really don't think it is that critical.
Shim it till it cuts right. That's it.
What would you do if you didn't have the internet?
Exactly.

-D

[EddyCurr]

I'll give that 7% a try.

Be aware that the suggested clearance percentage applies to the gap along the interface of ONE cutting pair (top & bottom knives).

Your Makita JS1601 is a double-cut shear design. It effectively has TWO cutting interfaces - set clearance on each side to 7% of material thickness (for mild steel) to start with and then inc/dec from there as indicated by edge quality.

(By comparison, the JS1602 is a single-cut shear design. Just one cutting interface to adjust to 7% of material thickness.)