Workshop: An introduction to Plasma-Cutting and welding from solaz.biz, Emily Mann, Tanque Verde area Metal Artist
You will leave with: Two Plasma-Cut pieces and a Welded Flower, maybe more. Examples of student products are below. The workshop activities include:
Plasma Cutting – Make yourself a personalized nameplate or other sign to practice
learning to slice through metal like Thor. Then, create a pattern and cut a design into a sheet of metal, which we will roll into an arc to make a sconce. If you prefer another product, come with ideas and we will find the materials. Project suggestions include: address sign, outdoor signage, or personalized whimsy like a bird or mask on a stick.
MIG welding – practice running “beads” and joints until relatively comfortable and put your skills to use making a flower.
- Cost: $135, including insurance
- Duration: 4-5 hours, with snack break
- 2 participants, to maximize the time each gets per machine
- Schedule: Please contact me, 520-271-2641 to schedule a class. I can create one for you at your convenience, any day of the week. The most fun, is to find a friend and come as a two-some.
Workshop Studio Hourly Rate: $35/hr plus materials with access to most equipment. –I will do grinding for you on the bench grinder and cutting with the saws.
– In simplest terms, plasma cutting is a process that uses a high velocity jet of ionized gas that is delivered from a constricting orifice. The high velocity ionized gas, that is, the plasma, conducts electricity from the torch of the plasma cutter to the work piece. The plasma heats the workpiece, melting the material. The high velocity stream of ionized gas mechanically blows the molten metal away, severing the material. From Lincoln Electric. How a Plasma Cutter Works
I have an Hypertherm 380, a machine capable of cutting up to 1/4″ metal, but not with the cleanest cuts. I love it, but do with it had a drag tip to allow for gouging and less damage to the tip if it touches the metal surface.
- Spark jumps from electrode to nozzle. This causes some gas to become ionized.
- Pilot arc creates ionized gas path for the main arc.
- Approach the metal at an angle (60 degrees from horizontal, 30 degrees from vertical) and then rotate the torch to the vertical position. This way, the molten metal is blown away from the torch.
- Maintain a constant work distance – Optimally, you should maintain a 3/16″ to 1/8″ distance from the nozzle to the work. Moving the torch in an up and down fashion will only hinder your efforts.
- Don’t touch the nozzle to the work piece. Doing so will drastically reduce the nozzle life as the cutting will double arc through the nozzle.
- Minimize pilot arc time – Because of the wear it creates on the consumables, try to minimize the amount of time spent in pilot arc mode. To do this, position the plasma torch by the edge of the work before starting the arc so you can get right to cutting.
- Travel in the direction that will give you the best finished work – As you push the torch away from you, the better cut will appear on the metal that is on the right hand side, since it will tend to have a better, squarer edge. If you are making a circular cut and plan to keep the round piece as your finished work, move in a clockwise direction. If you plan to keep the piece from which the circle was cut, move in a counterclockwise direction.
- Adapted from Lincoln Electric, “Plasma Cutting Basics”
I have a Miller Dual Voltage MIG (Metal Inert Gas) Welder. I use it for beyond 1/4″ thickness metal confidently, but would not go beyond a 1/2″ piece. MIG is the easiest type of welding and a learner can quickly fee success. I generally use 16 gauge metal and thinner, up to 22 gauge, and thereby use a type of stitching bead where I hold the trigger for a bit less that a second and pulse it down the joint or seam. This is not the strongest type of weld, as the metal does not get as hot, but thin metal easily burns through and the ornamental and decorative work does not require the hardcore structural strength as say, a bridge (which would probably use Arc welding anyway).
Bead – the actual weld. Vanity welders are always looking to lay a “roll of dimes,” but the real goal is to produce a clean, full, solid well, free of inclusions that penetrates the joining pieces. Whether it is perfect to look at is less important that sturdy.
Consumables – The parts, like the electrode, swirl ring, nozzle, & retaining caps on the Plasma Cutter; the tip, cone and wire on the welder. Wasting this quickly adds up!
Wire Stick-out – Stick-out is the length of unmelted electrode extending from the tip of the contact tube, and it does not include arc length. Generally, maintain a stick-out of 3/8 in. and listen for that “sizzling bacon” sound. If the arc sounds irregular, one culprit could be that your stick-out is too long, which is an extremely common error.
Travel Angle – Travel angle is defined as the angle relative to the gun in a perpendicular position. Normal welding conditions in all positions call for a travel angle of 5 to 15 degrees. Travel angles beyond 20 to 25 degrees can lead to more spatter, less penetration and general arc instability.
Work Angle – Work angle is the gun position relative to the angle of the welding joint, and it varies with each welding position and joint configuration (see below). Lap joint (also a fillet weld): Angle the gun between 60 and 70 degrees. The thicker the metal being welded, the greater the angle.
Parent or Base Metal – The piece to which you are joining.
Favorite Video Resources
- Miller Welding Principals (3:18)
- Machine Set-up & Running First Beads (Bead part comes around 21:34)
- Jointing Things (20:00)
- MIG Welding Trouble-Shooting, Tips & Tricks (ChuckE2009 on YouTube – a great teacher and so cute!)