Making the Mighty Goliath Hotwire Machine!





Introduction: Making the Mighty Goliath Hotwire Machine!

Complete instructions for the making of the Mighty Goliath Hotwire Machine. Materials and directions are shown in each step, image notes. See my other instructables for sample work, signs, etc. Creativeman.

Step 1: Additional Instruments Made With Same Technique

I have made several instruments like this, namely to use in a class I plan to hold. I think it is a viable art form and is relatively unknown to the general and artistic community. People find it hard to believe you can get such detail in the lettering. Try it, I think you will like it. Disclaimer: IF YOU DON'T UNDERSTAND THE ELECTRICAL WIRING, DO NOT ATTEMPT! GET QUALIFIED ELECTRICIAN TO HELP. I have used one of these machines for 15 years with no problems, not even a broken wire. So if things don't seem to be working right, you have probably done something wrong. A few additional tips: Try to keep temperature as low as possible. You want to melt the foam, not burn it. Use only with adequate ventilation. Some people may be sensitive to the vapors produced. Use care around the wire! It is hot and will burn you. Don't let young children play with it. It is not a toy.

Step 2: Pieces of Project Needed to Constuct Instrument.

Most pieces of the instrument assembled together for this instructable. The transformer, dimmer control and wires will be added in the next view. View image notes for a complete explanation of the various parts.

Step 3:

Electrical components needed for the machine. All items are listed in the image notes.
Costs: Electrical cord: $1.25; Transformer: $6.90; Dimmer switch: $4.99 (push on/off type); Nichrome wire: I bought 100 feet for $2.50! Wood parts probably add a dollor or so to costs, same with various mounting screws/hardware. So for between $10 and $20 dollars you can have your own hotwire machine. I have seen these on the web for much more money. This machine will accomplish the same thing. I have made larger machines to be able to cut larger pieces of styrofoam, or EPS foam. I just changed the length of wire, the transformer and the sizes of the wood components, obviously.

Step 4: One Example of a Dimmer Control

In this picture, an inline lamp dimming switch is shown. It seems to work ok, although has not been tested over time. This type of control is quite a bit more expensive than dimmer switches used in other models.

Step 5: Closer Look at Arm Assembly

This is a close up of one arm made for the blue machine. All are similar. These two pieces are made of common pine lumber, 3/4 inch thick. The arm it self is about 8 inches long by 3/4 by 1/4in. Pieces are glued and screwed for strenght.

Step 6: Apparatus for Testing Various Components and Wiring Details

This is a helpful item to test transformers, switches, wiring, etc. before final assembly.

Step 7: Details for Mounting Dimmer Switch.

Shown in the pictures are the milling or routing of a depression for mounting the dimmer. Placement of dimmer and knob are shown.

Step 8: Bottom Mounting Piece Details

In this shot, details of the bottom wire mounting piece are shown. A 1/8 inch hole is drilled in the end of the wood piece to accept a 8-32x1in. machine screw. To this screw, the power wire from the transformer and the hotwire itself will be attached. In the center of the bottom mount, a 1/2 inch hole is drilled with a forstner bit. A 1x6in. wood screw with washer is used to attach the piece to the table. By moving the mounting piece slightly in any direction, hotwire can be adjusted to be plumb in two directions and give right angles when slicing through the foam.

Step 9: Top Arm Details

Here, the top arm has been drilled to accept the machine screw as shown. The hole is 1/8 in, and the machine screw is an 8-32x1in.

Step 10: Cutting Stencil for Painting on Name

A stencil is made by selecting the fonts used on the word processor, printing the words out in duplicate, and then cutting the stencil with a craft knife, or scalpel.

Step 11: Making Design Decisions

Shown are various instruments being tested for color combinations, placement of components, lettering choices, and so on. See image notes for more details.

Step 12: Completed Instruments, Ready to Go to Work

Many hours of creativity lie in store for the craftsperson who has one of these. Enjoy!



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Awesome job Creativeman. Do you sell these machines? Do they take 110 or 220 electric? I'm sending you a message.

Couldn't you use flat screws here?

is it possible for this machine to help me cut MDF?

Good gravy , it's a great IDEA for an Instructable but you don't say how to do anything .If this is how your classes are going to be taught you are going to have disappointed students and you are going to be frustrated .A simple wiring diagram and a picture of how to make the frame is all you needed .Two steps , less showing off the " Mighty Goliath" . At least you tried to share .

See step 6. (and quit whining). Cman

I'm new to this so please bear with me.... I live in asia the power voltage is 220V....could i just wire the whole thing up to a ac adapter which has adjustable voltage like 3v . 4.5v . The adapter says PRI :AC 220V 50/60Hz , SEC: 3-12v 600mA. I don't need a dimmer and Transformer right? cause i haven't the faintest clue in how to do that. I've read some use batteries.... so could this work? what voltage should i use? 4.5V or 6V. BTW no one here knows what nichrome wire is....( could be cause we talk a different language) what can i use as an alternative? floral wire?. Please give me an answer. Thank you

Perhaps because I am a female, perhaps because I have blonde hair, perhaps because I live on the other side of the globe, perhaps perhaps perhaps.... I cannot figure out what to do with this Instructable. Is this a prefabricated kit?? Step 2. What size is the base board? What size are all the pieces of timber? What is each piece of timber for? Don't really care that they were cut with a band saw. Steps 3,4 & 5 are nice. Which order do I attach things, and where, and how? Step 6 I can see what you're trying to show us, I just think it's done poorly. Step 7 I suddenly need a router Step 8 is as clear as mud to me. And when was I supposed to attach the transformer? Step 9 What is the best method you've used to get flat edges on a screw and then drill a hole into it? Or is it a prefabricated item? Step 10 is a total waste of time so far in any attempt at this project, nothing has been put together yet? Step 11 another useless step when I can't figure out the first 9 steps Step 12 Your natural coloured machine shows the transformer on the top. Is that were it's supposed to be mounted. I appreciate the effort you've gone to with this Instructable, however, alot of it is more about what you (creativeman) can do, rather than clear instructions which would allow anyone else to build it. I have carefully read every word and looked at every picture and read every note on the pictures, and I am still none the wiser. Finally, how do I attach the wire? do I just twist it on and hope for the best?

There is much more information in some other Instructables just type in " hot wire foam cutters "when you search . There are at least three more that are helpful .Read the comments also , because there is more help there also .Then just make one that will be the right size for your project .

You really took the time to give a good critique jaydeechick a lot of the stuff can be made whatever size you want . I'm sure you can use whatever tools you have at hand . I just wish he told us a lot more about the electrical stuff .While he means well it's just not helpful .Maybe if we post it on the Forums an electrical hacker can help us out . By the way I learned long ago not to underestimate a blond female regardless where they're from and the pretty ones you have to watch the closest . Now creativeman is going to tell us we are whining because we noticed there are problems

How is that helpful at all?