The Home Machinist!

First off I will say--I have no professional metalworking experience. So this might be a really obvious matter but I cannot find it explained anywhere.

Recently I bought some Grizzly machines just for hobbyist use. One of the machines was the G4011 3-in-1 sheet metal machine.
http://www.grizzly.com/products/Sheet-M ... -30-/G4011

So far I have just been setting up my "shop" room, and so I have not really used the sheet metal machine for anything at all yet. Just occasionally looking and playing with it I could figure out the slip roll feature (the triple rollers on top), the shear (the bottom of the lower moving section) and the bending brake (the top edge of the lower moving section, and the stationary box fingers).

I was hoping that it could press-brake also (that is--create folded-over edges on sheet metal) and I assumed it could because the user manual mentions a "pressing" feature, on page 6:
http://cdn0.grizzly.com/manuals/g4011_m.pdf

If you go to the end of the user manual, there is a parts diagram that shows part #10 as the "pressing plate", toward the upper-right corner of the sideways parts-view.

The thing is, this doesn't work for pressing anything, at least anything that is useful. It seems more like a steadying device to help with shearing. It only lifts up about 1/8-inch off the table on the blade upswing--and can't really press down on anything very hard because it's only held down by compression from a couple fairly-small springs.

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Grizzly also makes a larger 3-in-1 sheet metal machine, the G0629.
http://www.grizzly.com/products/52-3-In ... hine/G0629
It is very similar to the G4011, basically just a larger version of the same thing.

First odd thing I noticed is that the G0629's owners manual has almost three times as many pages as the G4011 does, yet the machines are basically identical.
???

The second odd thing is that the G0629's manual does not mention any "pressing" feature at all, even though the G0629 has a functionally identical part (#17 in the exploded diagram, at the end of the user manual). The G0629 manual only mentions rolling, bend braking and shearing, and calls the mystery part a "clamp bar", not a "pressing plate". On page 34 they say it is a "hold-down clamp" and also functions as a finger guard for the shear.

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Oddly enough--because of some beveled grooves cut across the shear table, I think I could make a part that would fold edges over, so this is not hardly a disaster. I just have to wonder what the G4011 "pressing plate" is really supposed to do. To me it only looks like a clamp to help hold the metal steady during shearing.

Somebody here is confused; is it me or is it the person who wrote the Grizzly G4011 manual?
~

Without seeing the machine, or the literature, I'm inclined to think you are correct. Shears have a bar that hold the material while it's being sheared. Otherwise, it's inclined to tip due to the bypass nature of the shear.

Harold

I agree. Pressing plate secures the part hard against the bottom knife. I'd say the writer got carried away proclaiming "features".

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Measure once, measure twice - outsource it.

I find this fact to be present with many import machines. The fine language they use, does NOT translate well into a technical instruction source, so meanings may come from a thesarus of wrong statements.

Generally speaking all flat shears of any length have a pressure or hold down bar, that serves as a way to keep creep out of the shearing process, and guard human parts from getting into the cut areas.

If you are going to Press any sheet metal, the size of the machine goes up dramatically in tonnage for even small pieces to be pressed and shaped or drawn, even in light guages. Many machines that claim forming attributes are form lockers and edgers, and rolls and such, that have something like 22 G or 18 G capability, and not really usefull beyond household ductwork.

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Big Dave

Be Alert! The world needs more Lerts.

What angle will the unit bend to?
When I was a coachbuilder we made small access hatches by bending the sheet edge back on itself leaving only 30 degrees or so to go, lifting the fingers would then allow this narrow section to slde under, clamping the fingers down again resulting in a nice folded edge.
Regards,
Nick

These two units will only bend accurately to a right angle. The dies are pointing down with a 90º edge on them, and push into a "V"-shaped notch.
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A press brake as oppposed to a finger or box & pan brake.

Harold

Doh! I went to the site, and I have seen the harbor fright similar unit, and am not impressed for the price. It is why I am making dies in soft metal, and taking die parts from Ebay, to fit my 50 toan axle press. I have a home built bending brake, but it leaves something to be desired on geeting a square corner on 16 Ga metal or better on its 52 length.

Face it, tools are expensive. Industrail equipment has industrial prices.

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Big Dave

Be Alert! The world needs more Lerts.