Shear_modification

[Cullen]

Greetings,
I am new to some of you, but it was suggested that I post this info here. I recently went through a purchase and modification to an inexpensive shear from Harbour Freight ($279). I needed to cut some .022" #304 stainless steel. Out of the crate, it will not cut this material, after making a couple of simple (in retrospect) mods, it works fine now. I posted an article and pictures at http://metalworking.com/dropbox/. for anyone interested. The heading start is shear_mod_*
cheers and enjoy,
Cullen@AzFiveStar.com

[mixdenny]

Excellent example of how a little engineering can turn a marginal tool into a real performer! I have been looking at the same machine for some time. I take it that it requires a high effort for the shearing operation?

Denny

[NAMPeters]

Did you follow up with jam nuts to lock-in your final setting on the 5 bolts?

[Cullen]

Denny,
Actually the effort is slightly less when it is shearing. Otherwise it is pulling material between the cutters and tends to jam up. There is a "crackling" sound when all is working well.
Cullen

[Cullen]

Neil,
There are no jam nuts. The threads are fairly snug, plus there is no rotational force being applied to them. I think one they are set snugly, they should stay put without much effort. Time will tell.
Cullen

[Cullen]

Denny,
I have already been thinking about how to put a large diameter pulley on each end with a cable leading down to a foot pedal underneath the table. That should have multiple advantages. First of freeing up both hands to locate the material, add a little umph to the force and give an evenly distributed force to each end of the blade. Right now it is only being applied to one end with the bar.
Cullen

[Scott]

Cullen,how does the shear do with some .062 aluminum?As far as how hard it is to pull the handle.Seems like you made that tool about ten times more valuable,atleast to me.Great now I need another tool. [img]/ubb/images/graemlins/grin.gif"%20alt="[/img]

[Cullen]

Scott,
I was able to shear a piece of 0.092" aluminum, but, it was quite a strain. I don't believe that the .062" should be too much of a problem at all. I was able to breeze through a piece of .032" cold roll sheet with little or no effort. The stainless however is a real nasty bugger to cut. It is "gummy" and tough at the same time. The majority of my jobs can get by with .032" aluminum.
Cullen

[jpfalt]

That shear in unmodified condition will handle .062 steel without a problem. I have cut up to .108 aluminum in 6" widths with a little oomph on the handle.

The mods Cullen did allow it to cut thinner material without rolling the sheet between the blades when they deflect, which makes it super for thinner materials. The heavy stuff doesn't roll over the edge as easily and so cuts OK on the unmodified shear.

I have the same type shear as Cullen and plan to do the same mod to it.

Super job Cullen!!!

[captainkirk]

I was reading about your shear mods, and looking at the pictures and noticed that your last modification seems to assist in the rigidity of the cutting bar from the back. The part I noticed is that in your picture "9" there is a piece of curved strap metal (existing stock support) on the piece that is to be made stronger by your added brace. It seems from a design point that the weak strap metal might be replaced by a solid plate laid on edge (Hard to describe) if the plate was shaped close to the shape of the band iron strap it would provide a much more robust support to the cutter and keep the warping problem from occuring. Their design is fair but the strength of that strap isn't near high enough.....just a thought from what I could see and it might be easier to accomplish.
good luck