WELDING PLATE STEEL GRADES A36, G50, G70, T1

[JRP]

I want to build a grapple. The local steel yard has four grades of steel in 1/2" thick: A36, grade 50, grade 70, and T-1.

I'm looking for information or help about how hard it is to drill, grind, and weld these grades.

The plate parts will cut with CNC plasma, with no need to drill holes, but I'd like the ability to drill holes if necessary, even if a cobalt bit is required.

The higher grades are more expensive, (T-1 is 2X cost of A36) but stronger and weigh less. For a grapple, lighter increases overall lifting capacity so I'm willing to spend.

What comments do you have about fabricating these steel grade?

My welder is a Millermatic 250.

The design I want to build

YouTube - Quick Attach Eagle Talon Heavy Duty Log Brush & Rock Grapple

 

[spo307]

A36 is most common mild steel and very strong, it can be drilled but again 1/2" is thick for drilling, use a hogan or iron worker to drill or punch the holes. as far as fabrication it all depends on the machine it is attached to break out force, lift capacities etc. IE light, medium and heavy duty attachments, go to places that sell what your looking to build bring a camera and ruler and spec it for what your machine is capable of. good luck. as far as your mig can do just about everyhting. I use the same one

 

[AlanB]

Kind of simplistic I guess, but I usually look at what the commercial manufacturers are using to build similar products and use that.

An internet search of grapple etc. supply folks will tell you the grades of steel they are using for these products.

 

[shaley]

T-1 is abrasion resistant steel and it might be a good idea to laminated of tip A36 parts or pieces with T-1 if you will be using the grapple as a root rake. If you are just picking up brush piles and logs many people on TBN have built using all A36 components. A36 is a mild structural steel with a 36ksi yield stress. I like to use 6013 rod run on DC for welds. Do you have a set of plans or patterns for the rake.