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Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store by tbarnea on July 12, 2008

Table of Contents License: Attribution Non-commercial Share Alike (by-nc-sa) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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Intro: Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 1: Over View . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 2: The Y axis - Vertical axis (step #1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 3: The Y axis - Vertical axis (step #2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 4: The X axis - Horizontal Axis (step #1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 7: The Lead Screw (step#1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 8: The Lead Screw (step#2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 9: ACME Screw (step #3) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 10: ACME Screw (step #4) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 11: The Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 12: The Electronics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 13: The Stepper Motors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 14: Finalizing the machine (step #1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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step 15: Finalizing the machine (step #2) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 step 16: Videos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 step 17: Whats next ? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 Related Instructables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Advertisements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

http://www.instructables.com/id/Make-a-CNC-Hot-Wire-Foam-Cutter-from-parts-availab/

License: Attribution Non-commercial Share Alike (by-nc-sa) Intro: Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store Make a CNC Hot Wire Foam Cutter from parts available at your local hardware store like HomeDepot . This machine can be used to cut wings for RC planes, surfboards, crown molding, packaging foam and lots more The original design was built in order to cut RC wings (even tapered wings - where one side is different then the other side) Polystyrene (EPS and XPS) will cut using a hot wire - other foams - like polyurethane should only be cut with a blade or saw. When cutting, be careful !!! - wire will get hot, and some people may be allergic to the EPS fumes - always work in a well ventilated area.

step 1: Over View Most parts can be found in your local hardware store, like Home Depot.. The first prototype was made out of wood, but didn't look "professional" enough, so I decided to go with a more robust design made of steel. The design can be modified to almost any size. Keep in mind that for longer travel you will need a longer lead screw. The problem with a long lead screw is that because it its own mass, it will "wobble" in higher speeds. One way to overcome this problem is to move to a larger diameter lead screw. Another way is to move to a chain or belt driven design. Belt driven machines are usually 8' and longer but require the use of micro-stepping. An example of a machine larger then 8 foot would be a surfboard foam cutter. Some surfboards are up to 12 feet in length, the only way to cut these boards would be a belt driven or chain driven mechanism I will try to cover this topic in the future with a sample machine and pictures... We started out building a machine to cut wing cores, but soon after we discovered a huge interest in the machine for other industries - like moldings, architectures, surfboards, Logos, props, packaging Willow Sills, Casings, Wainscoat , Fascia, Crown, Parapets, Wallcaps, Pediments, Quatrefoils, Columns www.8linx.com


step 2: The Y axis - Vertical axis (step #1) If you are building the CNC foam cutter for RC wings, then you would probably need 10" max travel on the Y towers. If building a hot wire CNC foam cutter for props, crowns, moldings You would probably want to go with a 4' x 4' (X x Y) EPS Foam billets are usually 3' x 4' x 8' or 4' x 4' x 8' XPS foam comes in sheets of about 4' x 8' x (1" or 2" or 3" thick) If building a CNC foam cutter to cut Polyurethane foam - FORGET IT Polyurethane foam should not be cut with hot wire, but a blade or a saw There are CNC foam cutters for Polyurethane that work similar to a band saw But use a abrasive wire instead of a saw - click here for more information In this section we will build the two Y posts or towers (Y axis). The posts can be found at the fence section at Home Depot You can replace these posts by any other post as long as you are able to keep them from vibrating during the cut. Any vibration of the posts will result in vibrations on the wire resulting in "waves" or not smooth cut of the foam. The following can be found in the drawer section, you will need two 16" drawer slides The Home Depot Catalog number for 24" slides made by Liberty 7-81266-18070-4 www.8linx.com


step 3: The Y axis - Vertical axis (step #2) The above picture is of the 2"x4FT Post with foot - that's the Home Depot name Cat num: 204-008 Home Depot num: 6-39426-48607-7 measure 6" from the base, and screw in (or use a rivet gun) the slide to the post Make two of these units - one for the left side of the machine and one for the right side of the machine. www.8linx.com

step 4: The X axis - Horizontal Axis (step #1) This U shaped part (the X axis carriage) will hold the Y axis stud. Here is the Home Depot Catalog number for the part below: "Half Base" made by Company named Simpson Catalog number : C751-973 Home Depot num: 044315-10350 these parts were punched and then bent, when we decided to make our own parts we had them laser cut and bent - then powder coated www.8linx.com


step 5: The X axis - Horizontal Axis (step #2) Drill the 3 holes on the slides (24" slides), and mount the U shaped carriage onto the two slides using rivets or screws. You will need two of these units, one for the right side of the machine and one for the left side of the machine. www.8linx.com

step 6: The X axis - Horizontal Axis (step #3) At this point we have an Y axis carriage which is mounted on the X axis carriage. We used large 5/8" screws to hold the post in place on top of the U shaped X carriage. Now make the 2nd one - again you will have a total of two units. www.8linx.com

step 7: The Lead Screw (step#1) Using parts from Home Depot, I could only find threaded rods, I later found online, stainless steel threaded rods. For this section, I used a lathe and a set of tap and die. There may be ways around, but I chose to go the safe route. We later had ACME nuts made just for us - if you are interested in purchasing ACME nuts Please visit our online store at http://www.8linx.com/cnc/online_store.htm There are a few differences between threaded rods and ACMEs. Usually ACME have a lower inch per turn. A later design, we used ACME screws that can be found on ENCO - search www.use-enco.com for ACME threaded - here is the exact link Threaded rods www.8linx.com


step 8: The Lead Screw (step#2) If you use a 1/2-10 ACME screw and ACME Nut that means that the ACME screw will turn 10 times and during this time it will advance 1 inch. If you use 3/4-6 ACME rods and ACME nut - this means the ACME screw will turn 6 times and during this time it will advance 1 inch. When calculating the steps-per inch on a machine you need to know the ACME value and the stepper motor steps. For example: using 1/2-10 ACME with a stepper motor driver at 1/2 step - to calculate the steps per inch follow these steps 10 turns per inch times 200 (which is the usually stepper motor steps per turn) times 2 (this is the half step of the stepper motor driver) the total comes to 4000. This means that the resolution of your machine will be 4000 steps per inch If you decided to go with the ENCO threaded rods, you can buy from them the ACME nut as well. Here is the link ACME Nuts www.8linx.com


step 9: ACME Screw (step #3) A simple way to connect between the motor shaft and the threaded rod, is a plastic tube. A better way is to make this "Coupler" out of rubber - this will help in case the motor shaft and the threaded rod are not aligned. We later moved to ACME screws that can be found on www.use-enco.com. These ACME screws come is 3' and 6' lengths. Since their diameter is 1/2" and the motor shaft is 1/4" you will have to machine these ACME rods to 1/4" diameter. Use your lathe of stop by at a machine shop and they can do it for you. www.8linx.com

step 10: ACME Screw (step #4) Now, make another one just like it, but mirrored. The last picture on this page shows that the two "T" brackets are facing each other, This is where the hot wire will connect. For those who wish to mass produce wings, simply add one or even two more "T" brackets and you can cut 3 cores at a time. www.8linx.com

step 11: The Software There are a few software out there that will run the machine - some need special hardware - we spent months testing and evaluating many of these software and hardware. 1. FoamWorks software will work with the electronics in the package below - has CAD capabilities as well 2. GMFC - needs a timer module - without the timer the package below will not work 3. Mach3 is a generic CNC router software will work with the package below, but you need to be able to generate 4 axis g code. 4. KCAM - same as above - generic CNC router software - will do nice PCB boards as well 5. DeskCNC - is an additional hardware board that connects to the PC via the serial port and its output is the electronics package below, not very easy to put together but doable. Online store All of the software above other then DeskCNC require you to have a printer port on the PC If you are going to cut wings or simple shapes we would recommend the use of Foamworks If you want to cut complicated shapes and multiple shapes we would recommend DeskCNC or Mach3. We currently use AutoCAD to draw the shapes, then convert them into G code using DeskCNC, and the last step is to run the machine using Mach3. Here are some tutorials for all 3 software packages - we have spent many hours creating them, and they are free of charge to use or distribute !! www.8linx.com


step 12: The Electronics The electronics is the only part that is "kinda" hard to find. You can search ebay and look for "4 axis stepper motor driver". Then you will have to find 4 stepper that will match the drivers - pay attention to the type of driver you are getting. Some will work with Biploar motors and some will work with Unipolar motors. The last step is to find a power supply. The power supply should be around 24V 5A, but its best to get all of the electronics from one source. If you can't find anything on ebay try this The Electronic box works together with the software you choose. Make sure that the electronics you select can be programmed to accept pulse and direction for each of the 4 axis. Mach3, KCAM and Foamworks will all work fine Mach3 will only drive the electronics. Foamworks will also generate a file called "DAT" file, and with this file it will also control the electronics. Sounds complicated, but take a look at all these web sites and after a while things will start making sense. Mach3 - www.artofcnc.ca Foamworks - www.foamwork.net


step 13: The Stepper Motors Bipolar motors There are only two coils, and current must be sent through a coil first in one direction and then in the other direction; thus the name bipolar. Bipolar motors need more than 4 transistors to operate them, but they are also more powerful than a unipolar motor of the same weight. To be able to send current in both directions, engineers can use an H-bridge to control each coil or a step motor driver chip. Unipolar motors In a unipolar stepper motor, there are four separate electromagnets. To turn the motor, first coil "1" is given current, then it's turned off and coil 2 is given current, then coil 3, then 4, and then 1 again in a repeating pattern. Current is only sent through the coils in one direction; thus the name unipolar. A unipolar stepper motor will have 5 or 6 wires coming out of it. Four of those wires are each connected to one end of one coil. The extra wire (or 2) is called "common." To operate the motor, the "common" wire(s) is(are) connected to the supply voltage, and the other four wires are connected to ground through transistors, so the transistors control whether current flows or not. A microcontroller or stepper motor controller is used to activate the transistors in the right order. This ease of operation makes unipolar motors popular with hobbyists; they are probably the cheapest way to get precise angular movements. (For the experimenter, one way to distinguish common wire from a coil-end wire is by measuring the resistance. Resistance between common wire and coil-end wire is always half of what it is between coil-end and coil-end wires. This is due to the fact that there is actually twice the length of coil between the ends and only half from center (common wire) to the end.) www.8linx.com

step 14: Finalizing the machine (step #1) Clamp down both axis, one shown in the picture on the 1st slide. I use strong spring to keep the cutting wire tight. The spring also keeps the wire tight when cutting a tapered wing. You can get the spring in your local Home Depot. On some designs I have seen people using a bow instead of the spring design. I got better results with the spring, but feel free to experiment Here is a setup which I also use on my foam cutting bow. The router speed control can handle up to 15A And the power supply can supply up to 3.5A which is more then enough current for a 30" wire. (about 1.5A) The low voltage power supply is used to isolate the main voltage (110V) from the cutting wire. Another way to go would be to use an isolation variac - here is a good choice for one http://www.action-electronics.com/variac.htm make sure to get the isolation version !!! www.8linx.com


step 15: Finalizing the machine (step #2) The router speed control can be purchased at www.harborfreight.com for about $20 The router speed controller connects to the mains voltage and its output goes to a transformer (should be isolated) These transformers can be found in surplus stores like www.allelectronics.com Another way to go is to use an insolated variac - this is better since it provides isolation from the main power. You can find this variac at http://www.action-electronics.com/variac.htm Almost all variacs are NOT isolated, and by being not isolated, the user may get "zapped" if not careful. Use caution when powering the hot wire, try to stay at low voltage (below 50V), in some cased you may need to go beyond 50V - in case you have a long wire. make sure never to touch the wire or the springs. A hot wire CNC foam cutters as its name - cuts the foam by melting it before having contact with the foam EPS foam - expanded polystyrene at 1LB density can be cut at speeds from 10 to 20 inch per min XPS foam - XPS foam has an innate combination of properties that make it one of the most efficient insulating materials available. The closed-cell structure, responsible for the foamÃ¢â?¬â?¢s excellent moisture resistance, also contributes to its high compressive strength and superior thermal performance extruded polystyrene foams may need to cut at a slower speeds, from my experience, when cutting XPS foam, I use a thinner wire - about 0.4mm. XPS cut are generally smoother then EPS foams. Another kind of foam is EPP foam (the kind they make the Zagi wing flyer) - EPP (Expanded Polypropylene) EPP foam doesn't dent or break. It has a "spongy" quality to it, so on impact it compresses and pops back to shape Hot wire: We started out using stainless steel wire as our hot wire, this will work well, but the wire will not last long and can break under to much tension. If cutting a 2LB foam for a large project, wire breaking during the cut can cause a lot of $$ At a later stage we moved to Nichrome wire. Nichrome wire will last longer and will not break even when red hot. Keep in mind that the wire will tend to stretch when heated, so a spring is needed to keep it from sagging The software I use is foamworks (www.foamwork.net) This software is the most popular foam cutting controller software, and also not to expensive (about $50) It will control up to 4 motors and let you cut tapered wings and other shapes, take a close look at the site There is a lot of useful information there, and even a link where people www.8linx.com


step 16: Videos Cutting multiple shapes out of one 4' x 4' x 8' block of EPS foam


www.8linx.com

step 17: Whats next ? We plan on Building a CNC plasma cutter and explaining how to - step by step


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Comments 50 comments Add Comment

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rapidprototyping says:

Aug 14, 2010. 2:58 PM REPLY

cut four foam circles for this

rapidprototyping says:

Aug 14, 2010. 2:52 PM REPLY I see your plane parts and they look smooth . I have idea cut circles for savanious wind turbines. making four circles three or four feet in diameter should be no problem. next rout a couple flat bottomed s shapes into the discs use adhesives gorilla glue ,silicone to adhere the pieces together. My first HAWT was plywood and aluminum flanged pipe cut in half the foam is lighter and after assembly could be coated with polymers or powder coated with some coating to make it a uv resistant and possibly after further rounding over or stream lining. I hope adventually some one will do this challenge project. the cnc plasma could easly cut steel parts to support the foam at each disc attach it to the shafting fabricate bearing supports ect

isurfwater says:

Aug 4, 2010. 5:18 AM REPLY

Does anyone have a FREE design for one with a chain drive?

Light_Lab says:

Mar 28, 2010. 7:33 PM REPLY Pure Polystyrene foam contains no nitrogen so it is impossible for it to produce cyanide without additional compounds. Polyurethane foam does contain nitrogen and carbon so it can (and does) produce cyanide during thermal decomposition. All wire cutting though produces dangerous fumes and adequate ventilation is mandatory. An excellent idea is to use an old vacuum cleaner to collect the fumes and exhaust through a wet filter. I have hot wire cut PU foam but it requires a much higher temperature and a much slower cutting rate. It is extremely corrosive of the cutting wire and produces ugly charred patches. I would not recommend it.

slattermatter says:

Mar 24, 2010. 7:46 PM REPLY

Hey thank you for this tut. I want to make one like this except it will be 6' long and 3' tall. I have heard if the key screw is to long it will shake at speed. If I use a key screw that is a 2 start or 4 start the screw will turn slower minimizing the 6' key screw shaking, right. Do people use over 1 start with hot wire foam cutters?

tbarnea says: At 6' long you should use a 3/4-6 ACME screw or even a 1" ACME screw. Anything longer you will need to go for a chain or belt design


Mar 24, 2010. 8:43 PM REPLY

slattermatter says:

Mar 24, 2010. 9:42 PM REPLY What would the difference be if i used 3/4-5 ACME or 3/4-10 ACME. I know my motors would spin half as far to move the same distance, and they will be spinning slower to move the same distance... but is there any other drawback/positives that I don't know about?

tbarnea says:

Mar 24, 2010. 11:31 PM REPLY

Correct - at 3/4-5 your motors will turn 5 turnes and advance 1"

slattermatter says:

Mar 25, 2010. 7:32 AM REPLY Why do people always use ACME 10 TPI with foam cutters? all most every application I can find thats what they use.

mrubenb says:

Mar 21, 2010. 8:06 AM REPLY

Very nice work.

crunchie1000 says:

Feb 20, 2010. 6:37 AM REPLY i am going to make a similar design to this one and i was wondering if i could use threaded rods as an alternative to the lead rods as it will be cheaper. any advice? has anybody done anything similar? Thanks

tbarnea says:

Mar 15, 2010. 8:53 PM REPLY

you can get ACME screws at www.use-enco.com we use them on our machines www.foamlinx.com

WoR says:

Feb 27, 2010. 10:08 AM REPLY yes it would be cheaper, but it would you would have alot of backlash. The quality would most likely not be good at all. ACME rod is not that expensive, especially in the grand scheme of things when your building a cnc machine. i guess to better answer your question, could you - yes, would you be happy with the results - most likely not. Hope that helps

Loonytech says:

Mar 4, 2010. 3:11 PM REPLY

Haha! GO FOR IT !! And thnx for this one. Fantastic work.

Andy S. says:

Feb 10, 2010. 6:26 PM REPLY Is there any one willing to build this CNC Cutter for me I am in northern California willing to travel any were in California looking to cut 4X8 blocks of foam to make crown molding, Thanks

tbarnea says:

Feb 10, 2010. 7:25 PM REPLY

Hi there We are in northen CA - www.foamlinx.com

frmco says:

Jan 12, 2010. 8:40 PM REPLY Im a model maker and have cut wings from foam befor for a quicki 500 racing. and other types and all you need to cut a wing is couple of templets cut from formica and treight edge with music wire attached and powerd by 9V battery or 12 will do too then use weights attached to the streight edge with fishing line and set up the cut, easier than all of these mombo jumbo. LOL

vicsrc says:

Aug 26, 2009. 8:18 PM REPLY

has anyone built this cutter? how did you connect the horizontal axis to drive the vertical tower?

big8 says:

Jun 3, 2009. 3:15 PM REPLY From what I've seen so far, the cutter uses 4 independant motors. If these were arranged like a pen plotter it would free up at least one motor to use for a "Z" axis. A hot wire, in the form of a soldering iron tip could then vaporise the foam into 3D shapes. Obviously, some preforming would be needed. However, I'm new to foam cutting and about to embark on such a project, so if anyone can see a fault with this please shout before I get to far into it. Would appreciate some help with the electrical/software interfaces to.

macrumpton says:

Aug 20, 2009. 5:04 PM REPLY The problem is that a soldering iron is not quite hot enough to really vaporize foam. it will melt the foam, but it creates a gooey buildup on the iron that makes a mess when it blobs off. I am thinking that if you had a fairly high power laser that would be hotter and you could use short pulses to control the depth that it would melt/vaporize.


big8 says:

Aug 21, 2009. 4:31 PM REPLY Hi macumpton, ( like to know about name) My reference to a soldering iron was just a figure of speech. I agree a suitable laser may work and would have many other and better uses but is a little complex a setup and rather expensive for many. Don't really know enough but would like to know where to get one at a reasonable price if you can let me know. I was referring to a small loop of ordinary resistance wire like Nichrome V that can be made hot enough to do the job. Rotate it if necessary. Changing the subject I have discovered two rather good sources of slideways to use as axes. Secondhand drawing board slides and a cross country skiing machine. There must be many other gadgets out there, that can be used also. I got both lots for less than £10. They needed a little modifying to restrict unwanted lateral movements but have turned out very well and removed the prime cost components.

LWJCarroll says:

Jun 13, 2009. 6:47 PM REPLY FYI...to my knowledge cutting Polyurethane foam with a hot wire produces cyanide gas... (hence the warning) while polystyrene doesn't.......Rgds .Laurie

macrumpton says:

Aug 20, 2009. 5:00 PM REPLY I took a metal casting course where we made shapes out of styrofoam and packed them in a metal box full of sand. When you poured the hot aluminum onto the styrofoam it evaporated leaving a hollow space in the shape of the foam. This process would pick up a surprising amount of detail, right down to the wrinkles on the masking tape that you put on the foam. We were told to never do this without the ventilation blowers being on full blast because the polystyrene released small amounts of cyanide when it vaporized.

kinggato says:

Jul 18, 2009. 8:57 PM REPLY

nice

welgemoedr says:

Mar 30, 2009. 7:15 AM REPLY

i cant wait!

twrecks says:

Mar 15, 2009. 9:29 PM REPLY I love this concept - and the price seems right. NEMA23 bi/uni/polar motors can be had for for $12.95 ea at www.mpja.com. Just the thing for cheap R/C airplane fun. I plan to build the stepper control board myself. Also some folks on ebay are selling ACME rod machined down with delrin nuts for <$30 if that makes a performance difference - does it really matter? I would like 0.010" accuracy. Has anyone here (or posted elsewhere) besides the author built one yet? I really want to make one. It looks like some of the steps are not described - ie on the X slides, how is the drive nut attached to the carriage? It seems to me that the method used on the uprights (rivets) would interfere with the mount of the upright to the carriage. Also, how are the threaded rod end mounts made - that part is not mentioned or show clearly. It occurs to me that a 1/4"ID flange bearing should work there nicely I think - again I see em cheap on ebay. Also, can the Y motors be top mounted to lower the cutting height w/o added too much weight to the top and causing instability? Are limit switches needed or desired? How does one set the home position w/o them? Is there another forum that folks are talking about this machine? Tim

twrecks says:

Mar 16, 2009. 3:59 PM REPLY I came across some 1/4-20 "T" nuts with flange at Lowes (stock #137342), in the drawers next to the threaded rods. This is a blind nut with 3 "brad" holes in the flange, which takes a 4-40 tap well - for a $1.04 it seems to make a decent traveler, no metal lathing required to mount it. I think the outside of it would take 5/16 thread OK too (0.304" D). Still working on the end holder.

sgt_rock says:

Feb 5, 2009. 5:30 PM REPLY

clearly i'm missing something. what cuts the foam?

twrecks says:

Mar 16, 2009. 7:30 AM REPLY

the hot wire...

snowpenguin says:

Mar 4, 2009. 5:38 PM REPLY

The hot wire cuts the foam...

IW5 Industries says:

Dec 25, 2008. 12:24 PM REPLY

so its an electric etch-e-scech that cuts foam?

saltydog95 says:

Aug 7, 2008. 4:27 AM REPLY Hey, how does the hardware/ software of this thing work to make the tapered wings? Does it use each side independently to cut the different profiles on the right and left side at the same time?

trebuchet03 says:

Jul 14, 2008. 7:45 PM REPLY Is there such a beast as a 3 axis hot wire CNC? Can I index the bed and spin 90 degrees? For perspective... I want to make something akin to the photo below - well, a mold for it anyway... I would think, depending on design, I wouldn't be able to cut everything, but it would cut down on hand sanding time :) And I imagine I'd need a belt drive due to the long length... Or maybe I need to make a hot stick CNC and remove material that way....


Llewner says:

Jul 18, 2008. 6:02 AM REPLY

You need one of these: http://www.zcorp.com/Products/3D-Printers/ZPrinter-310-Plus/spage.aspx

trebuchet03 says:

Jul 18, 2008. 9:31 PM REPLY I guess it's hard to see the scale from that picture - that thing is about 8+ feet long (that one is not the one I was involved in, but is a great example of the compound curves involved) :p I've used a zcorp machine for printing parts - but, here's an FDM I made a few months ago for this past year's project (second picture is of the model in a water tunnel). Oh, this is a fairing for a human powered vehicle ;) The last picture shows the stacked cross section method...

Llewner says:

Jul 21, 2008. 6:42 AM REPLY Nifty! Actually, my comment was a bit of a joke. I used to build kayak's and know that foam stacking process all too well. ;) But just imagine if there WAS such a thing as a 12' zcorp! ;) Minimal sanding and insta-mold!

Pkranger88 says:

Jul 18, 2008. 10:46 AM REPLY I run the 3D Prototyping Lab at NIAR . We have a Z406 printer. I highly discourage this technology for anything that needs tolerances or is used for fit of function.

likes56 says:

Jan 9, 2010. 10:36 AM REPLY hi! I was just thingking is there a 3d printer that could produce an aluminum output or any type of metal? things would much esier and more faster in the field of manufacturing and engineering...just thingking how will this things be made, since designs are abundant...and just can't wait when will this things be made or even see how will this machine works.^_^.

Pkranger88 says:

Jan 9, 2010. 2:56 PM REPLY Direct Metal Laser Sintering is a process that uses a powdered form of a metal, i.e. titanium, chromium cobalt, aluminum, stainless steel, and builds the part layer by layer by sintering the powder together with a laser. I've priced out an EOS Direct Metal Laser Sintering (DMLS) last year. It costs around $540,000 and an extra $20K for the titanium setup. Other companies make them, but they are still tremendously expensive. My wife and I were considering purchasing some RP equipment in support of my product development company.

likes56 says:

Jan 9, 2010. 5:47 PM REPLY Thanks!..i just saw the video from youtube it was really impressive....how quick it is from design to its actual prototype....just cant keep on wondering how much faster will it be in the coming future...

Llewner says:

Jul 18, 2008. 12:07 PM REPLY I don't even see the Z406 on their site anymore. We have been working with Zcorp on a new product manufacturing application and have had no problems with their newer machines. Perhaps your issue has been resolved in newer models.

Pkranger88 says:

Jul 18, 2008. 12:53 PM REPLY Rapid proto can be done any # of ways. ZCorp printers are great for color prints, desktop models, form concepts, surface verification (we've done some models from video games, etc. ZCorp Printers are bad for Fit and Function prints due to their anisotropic scaling that results from the powder prints. From my industry contacts, the newer machines have improved the "processing" of the parts, but the accuracy of the tolerances and the quality of finer detail is still an issue. I print a lot of aerospace prototypes with very fine edges, etc. The 310 has a smaller print capacity than ours though it is more automated. If I had it my way, I would have both a ZCorp and a FDM or a SLA machine. What organization do you work for?


Llewner says:

Jul 21, 2008. 6:38 AM REPLY Yeah, our tolerances aren't THAT tight. I work in the graphics / display / signage industry and we can generally fudge up to 1/64" on a lot of stuff. Though I can say that the zcorp tolerances that we have observed are much tighter than that. I can see how it might not work in aerospace and such, but it is generally fine on less rigorous applications. As for our application, I can't really talk about the specifics of that we are developing other than to say that it has to do with the forthcoming ADA (American's with Disabilities Act) guidelines.

omnibot says:

Dec 25, 2008. 1:57 PM REPLY

How about a fab@home or a RepRap . They're based on making usable parts.

Ceriand says:

Jul 17, 2008. 6:17 PM REPLY You could probably make it work with this setup if you added a 3rd axis to rotate the block of foam. Of course, you could only reliably make convex or axially-symmetric shapes.

Edgar says:

Jul 17, 2008. 3:06 PM REPLY

How about the model boat makers techinque, draw a set of slices, sandwich them, then sandpaper them into a curve.

trebuchet03 says:

Jul 17, 2008. 3:21 PM REPLY

Check this out So that's the current method I'm using - but I'd like to save time and potentially some money by making it from a single block of foam - with a decent degree of accuracy :)

Edgar says:

Jul 17, 2008. 3:12 PM REPLY Wait, complex curves can be made, to a point... Just make the 2 points were the wire sticks from, move in angle to each other, i.e. one higher, one lower, then leveled, the to the other side. How? Hummm... Get some 3D wizz to do a program!

Edgar says:

Jul 18, 2008. 1:03 AM REPLY

...Or see this: Foam cutter

tbarnea says: This would look like a 3D CNC router job

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Jul 15, 2008. 9:03 AM REPLY

Make a CNC Hot Wire Foam Cutter - CNC

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