Netgear Gigabit Switch

In part two of this article I am going to be talking about each piece of networking equipment and how it interacts with the network and its importance.

The basic goal for any network is to create a reliable, fast and easy to maintain infrastructure. Our network had the following criteria:

All Television, Telephone, and Internet is to be powered by Time Warner Cable (TW).

• Telephone via TW VOIP, Using the 66 block all house phone jacks work.
• Television via TW Digital Cable, our house has two High Definition, and two Standard Definition TV’s.
• Internet via TW High Speed Internet, by setting up a simple network we can share this with our 6 computers and have network enabled backups.

In the last article we talked about our goals for the network and outlined the network map. Below we talk about each device and what it does.

Cable Modem

• A cable modem is a type of modem that provides bi-directional data communication via radio frequency channels on a cable television (CATV) infrastructure. Cable modems are primarily used to deliver broadband Internet access in the form of cable Internet, taking advantage of the high bandwidthof a cable television network. They are commonly deployed in Australia,Europe, and North and South America. In the USA alone there were 22.5 million cable modem users during the first quarter of 2005, up from 17.4 million in the first quarter of 2004.

Voice Over IP / ATA

• An analog telephony adapter, or analog telephone adapter, (ATA) is a device used to connect one or more standard analog telephones to a digital and/or non-standard telephone system such as a Voice over IP based network.

Patch Panel

• Patch panels offer the convenience of allowing technicians to quickly change the path of select signals, without the expense of dedicatedswitching equipment.

Network Switch

• A network switch is a computer networking device that connectsnetwork segments.
• The term commonly refers to a Network bridge that processes and routes data at the Data link layer (layer 2) of the OSI model. Switches that additionally process data at the Network layer (layer 3 and above) are often referred to as Layer 3 switches orMultilayer switches.
• The term network switch does not generally encompass unintelligent or passive network devices such as hubs andrepeaters.
• The first Ethernet switch was introduced by Kalpana in 1990.

WiFi Router

• Wi-Fi (pronounced /?wa?fa?/) is a trademark of the Wi-Fi Alliance for certified products based on the IEEE 802.11 standards. This certification warrants interoperability between different wireless devices.
• Wi-Fi is supported by most personal computer operating systems, many game consoles, laptops, smartphones,printers, and other peripherals.

Apple Airport Express

• AirPort and AirPort Extreme are local area wireless networkingproducts from Apple Inc. based on the IEEE 802.11 standard (also known as Wi-Fi).
• AirPort and AirPort Extreme in common usage can refer to theprotocol (802.11b, and 802.11g and 802.11 Draft-N, respectively), the expansion card or the base station.

Now that we know what each device does I will explain how each one is connected to each-other.

Starting with the feed coming into the house, we have a single RG6 drop from the utility pole and from there it goes into the garage utility room where it is then split off into its appropriate places. It first goes into a 3 way -5.5db splitter where it goes to the Cable Modem, Telephone ATA, and Television Amplifier.

Television Splitters and Amplifier.

Television

The signal coming into the 3 way splitter is low to begin with and is causing some of our HD channels to come in pixelated at times, so the only way to combat that was to install a Multimedia Drop Amplifier that has a +20db output signal. After the amp I have a 8 way splitter with 5 rooms connected, leaving 3 ports free, on those 3 I put terminators on to prevent signal loss and interference. With the new amp and splitter installed, the televisions are all now working much better and very rarely do they go blocky.

Phone

66 Block

Since we are using VOIP for our phone service I wanted to have the phone signal going though to all the wall jacks just like a normal POTS (Plan Old Telephone Service) does I decided it was best to use a 66 block and by using the new wiring I installed previously I was able to connect every room that has a phone to the VOIP service. This also allows for us to easily upgrade and add additional lines of phone and or digital extensions if we decide to install a PBX phone system.

Ethernet

Patch Panel

I connected the Cable Modem to the Patch Panel where it then goes up into the office and is connected to our Belkin WiFi Router, I setup the WiFi with a secure WEP password and MAC address authentication. I then connected one of the LAN ports to the second ethernet wall jack returning to the Patch Panel, this is where I have my 5 port Gigabit Switch located, from the Patch Panel I have one port as the uplink and then the four remaining ports plugged into the three remaining rooms and the fourth connected to my Ubuntu File Server (Future Article).

You may be wondering why I decided to place the Belkin Router up in the house? Well I did that because as with most consumer networking equipment, it will randomly lockup and need the occasional reboot and by having it in the house it saves a trip down to the garage.

In one of the bedrooms I then have a AirPort Express connected to the ethernet wall jack, this is used for printing and wireless music playing. One advantage of having two WiFi routers is the possibility of setting up a Guest Network, with this we can have it open and not secured, but we can isolate the WiFi network from the Physical Wired Network and Computers.

In this article i will talk about setting up a home network and centralizing the entire home telecommunications into one central location out of the way of normal life.

This article is based on my house and a few years ago I had spent 2 weeks completely rewiring all the telecommunications of the house and relocating it from outside the house to the utility room in our garage, this required installing over 1000 ft of Cat5e ethernet cable used for both Ethernet and Telephones and 500 ft of RG6 television cable. Each room received three Cat5e cables and two RG6 cables, this provided for 2 Ethernet, 2 Telephone and two Cable Television ports.

The reason I choose the utility closet to use for the telecommunications room was done after careful research and planning, the garage is on the lower level of the house and stays cool year round allowing the equipment to stay cool and not worry about overheating. The second reason for this was the ease of running wires to the attic, In this setup I have a 2.5“ bundle of wires running into the attic where it then is split to each room. Another advantage of having the networking equipment located out of the normal day to day area is the network becomes seamless and you don’t see networking cables and tv cables running all over the house, It gives the house a much nicer feel.

I will not be going much into the actual installation of the network, but more the hardware and the reason it is hooked up this particular way.

To start here is a breakdown of the network setup and the requirements:

• 2 Ethernet, 2 Telephone, 2 Cable TV ports / per room.
• Central location for Patch Panels, Splitters, Amplifiers, Switches, Modems, and File Servers.
• Provide Battery backup for VOIP Telephone (Voice Over IP) Service.
• Gigabit Wired & 802.11 b,g,n Wireless Networks.

The list of equipment currently installed (in order from Time Warner Cable -> Computers / Telephones):

1. 3 Way Splitter -5.5db
2. Port 1 Cable Modem, Port 2 Telephone VOIP ATA, and Port 3 +20db Multimedia Drop Amplifier
3. Amplifier to -> 8 Way Splitter to televisions
4. Telephone VOIP ATA -> Telephone 66 Block
5. Cable Modem -> Patch Panel
6. Patch Panel -> Belkin WiFi router (located in office)
7. Belkin Router -> Patch Panel
8. Patch Panel -> Netgear Prosafe Gigabit Switch
9. Switch -> Patch Panel (one switch port for each additional room)

In Part 2 I will talk about each component and its relationship to other components on the network, and why each one is important.

The supplies needed for this was:

• One Gallon Paint
• One Gallon Primer
• Paint Activator
• Primer Catalyst
• Laqour Thinner
• Measuring Cups
• Stirrers
• Sand Paper Varied Grits 60 – 2000 Grit
• Polishing Compound
• Electric Buffer Polisher
• Spray Gun ($14 Harbor Freight)
• Air Compressor and Hoses
• Tack Cloth
• Bondo for smoothing body panels
• Resperstor masks!!! !! Very Important !!

The paint supplies cost us about $350.   This included everything but the aircompressor and air hoses. Everything else on the list had  to be purchased.

Once we had finished researching how to paint a vehicle and we had all the supplies,  it was time to start prepping the body of the Jeep.

First we had to remove all the trim and windows from the Jeep.  Most body shops just tape around all the trim but we wanted to take the time to do it the right way, which meant removing any windows that could end up with some paint mist on them.   Ditto with all the rest of the trim and door handles, resulting in only tape off three parts which ended up being just the door locks.

The Jeep had been repainted at one time in it’s sordid past,  using spray paint (rattle cans).  Because of this, the paint was chipping and flaking away, which meant we had to sand down past the spray paint and create a smooth clean surface at the original primer level.

 Then we started to remove the old paint to do this we used both power sanders and manual sanding to get the entire Jeep smooth and clean.  We then used water and tack cloth to clean any dust away.

The next step was to closely inspect the entire vehicle and look for any low points or voids in the surface; any spots found we used Bondo to fill and then sanded smooth. After that it was time for one final wash before we sprayed the first layer of primer down.

Now that the body is prepped for paint it was time to mask and tape off any parts that are not to be painted ; we used paper and tape for the window trim areas and the front and rear bumpers.

With the Jeep taped up it is now ready for its first layer of primer, we used a Nasson brand epoxy primer. This type of primer is very good and is extremely tough, but requires careful preparation.   Prior to spraying, we had to mix the proper amounts of primer and catalyst together, (follow the instructions on the can carefully!) We also had to thin it with lacquer thinner so we could spray it with our spray gun.

For spraying you want to keep the gun at a 90 degree angle to the body panel you are spraying.  For each pass overlap by 50%, this will help create a even paint job without to much buildup of primer.  After two layers of primer we one again sanded the Jeep, but this time we “wet sanded” using 600 grit paper. The purpose for this was to remove any bumps from the primer and smooth the surface to assure good adhesion for subsequent coats.

The mixing of the paint is similar to the primer but instead of a catalyst we used an activator.  The activator causes the paint to cure to the touch in as little as 15 minutes. This is extremely useful and important for paint jobs like ours where one does not have a proper paint booth environment.  Curing the paint quicker means less chance for dust and other contaminants to adhere to the paint. We also had to thin the paint to allow it to shoot smoothly from the gun.

The first coat covered very well with a medium wet coat.  Never having sprayed automotive paint before it required a little bit of experimentation but after the second coat, we got more conformable with the process. The trick with the paint is to get the layers down as thick as possible without causing runs and drips;  you will also need to adjust your fan pattern to make sure it is spraying evenly and not focused in the center.

For the last coat we where instructed to spray a light mist layer 10-15 minutes after the last coat, We waited a few minutes to long and this created some orange peel, so we had to wet sand the Jeep and then polishing it to correct our “mess up”.

The process for wet sanding is exactly what it sounds like; you take water and high grit sand paper (1000 – 2000 grit) and carefully take a layer of paint off (making sure not to burn though the paint). This process removes the bumpy layer leaving a smooth but dull finish.

The final step in the process is to polish the paint. We decided to buy a power buffer / polisher and not do it by hand.  This made the job easy and created a great shine. One thing to remember is to not use polishes with wax in them;  you want to allow the fresh paint to fully cure or off gas for 40 – 60 days before you apply your first layer of wax to the paint.

Once you have polished the paint you still might have some residue from the poilishing compound.  Just rinse the vehicle with water and use a microfiber cloth to wipe it dry to  remove any leftover compund.

We started by removing the transmission from the Jeep and carefully examining all the components, we took a close look at the torque converter and quickly noticed that the oil bearing was stuck to the shaft. This would explain why the transmission was slipping, but since we had the Jeep apart we decided it was smarter to go ahead and put in a new torque converter and rebuild our spare transmission. 

The first step in the process is to source the parts, We have used Transmission Parts of Oxnard in the past and decided to stop by the shop to see what they had.  After a few minutes we where on our way with a new torque converter and all new seals and bushings for the transmission, the owner of the shop had a look at our clutch pack and we both agreed that it was unnecessary to replace them at this time because they had minimal wear. We also inspected the oil pump and sun gears for signs of wear but they all looked good with very minimal wear. 

Digging into a transmission may sound like a daunting task but it is really a strait forward repair and with a little patience anyone can do. We also recommend downloading the factory service manual for the transmission you are working on, this will have many detailed images and tips for working on your transmission.

After returning to our garage we carefully installed the new parts and reassembled the transmission, on this transmission we are able to use the torque converter to align the oil pump before bolting down (some transmission models require a special tool to be used).

We then installed the new torque converter and bolted back up the transmission, after filling it with 9 quarts of Dexron III fluid we started it up and then cycled it though all the gears to make sure the fluid has filled all the passages in the valve body. We let it idle to operating temperature  and checked the fluid level once more, after that we took it for a test drive. It drove good but it was not shifting properly, leading us to the Throttle Position Sensor (TPS) being faulty. Tests using a volt meter showed the sensor to be faulty and after replacing it and adjusting it to the proper voltage the Jeep then shifted properly. 

The total cost for rebuilding the transmission and new parts came in at a whopping: $245, if we had taken the Jeep to a transmission shop we would have paid over $1400 for the same repair. 

After a bit of research we came up with a list of major parts to install into the Jeep. 

1. Rubicon Express 3.5″ SuperRide lift 
2. Rubicon Express 1600 Adjustable Trackbar 
3. Doestech Shocks 
4. Rubicon Express SYE Flange, Custom Yoke
5. Coast Driveline, CV Rear Shaft
6. Nasson yellow paint & epoxy primer 
7. New master cylinder & booster
8. Interstate Battery
9. New pads, shoes, rotors, and drums
10. Peel – N – Seal for the floors
11. New Carpet, Seats, Headliner

So now that we had a list of the parts we needed it was time to order, we decided to get the lift online and the rest of the parts locally. After a week of part gathering we had a pile of parts ready to be installed.

In the next article we will show the process of rebuilding the transmission and getting the Jeep running.

While looking over the vehicle we where constantly making mental notes on the condition of different systems and what would be needed to get it to a running state.

Here is what we immediately noticed while inspecting the vehicle:

The bad:

• Transmission condition unknown – reported to slip but could not conduct a test drive
• Engine ran but needed assistance to start, indicating fuel delivery system issue 
• The Jeep was being used to store personal items and the suspension was worn out because of the weight 
• Gas tank filler neck was slashed preventing us from filling the tank
• Tires had been sitting and began to dry rot
• Paint had been redone with a rattle can 
• Interior had smokers smell and many stains 
• Tint was fading and turned purple
• No Keys for the door locks 

The Good:

• NP242 transfer case – 5 selection modes 
• 4.0 inline six engine 
• Renix Engine Control system 
• Pre-Chrysler we prefer the AMC era Jeeps as they seem to rust less and quality control seems a little better 
• Laredo Edition – Power windows, locks, AC 
• Body in mint condition minus the dodgy paint job

Getting the Jeep home was a different story, because it was 100 miles from our garage so we had to get it towed. Our first option was to rent a tow dolly and tow it with our other Jeep, this is not the safest option but we have towed a Ford Explorer before this way. But before we rented a dolly we decided to call AAA, as we have a Plus account that includes towing of up to 100 miles, so after a quick call we had a flatbed truck show up. The driver told us that we are not suppose to use the AAA towing for new vehicles that are previously disabled, but he knew that we where going to use it for off-roading and he also was into that sport, therefore he towed it without a problem. We went over the 100 miles by just 8 miles and had to pay $40 to the driver, we also gave him a nice tip for the help. 

Now that the Jeep was at our garage we had a chance to start the process of getting it on the road, the first thing we did was put some fresh gas in the tank and got the engine to start and run smooth. The next step was pulling into the garage and preparing for the transmission swap, but we will cover this in a later article. 

Now that we have the Jeep in our possession, it was time to register it; well it turns out that that was not as easy of a task as it sounds. We discovered that the previous owner had not registered it and there had been over $300 in DMV fees. After paying the fees and standing in the DMV for over 2 hours we finally got the Jeep registered. One thing we learned from this process is to always request a current registration when buying a vehicle, having known this before hand would have saved a lot of time and hassle. About 3 weeks later we received the title to the Jeep.

Since Obama’s election, it’s been very quiet here at Techimoto. In truth, we’ve had nothing much to rant about! Bush has evidently found himself some other hobby than trying to run a country, most likely trying to figure out how the Dewey Decimal System will work in his presidential library and hitting neighborhood yard sales on weekends to pick up a few volumes for the shelves. Cheney still rears his ugly head now and then, uttering some bitter ferocious nonsense regarding how the new guard is ruining everything, but in general, he’s also fading away from our collective 8 year nightmare.

Of course all is not perfect. Republicans still engage in some media spectacles, usually accompanied by shooting themselves a nice collective hole in their foot. The economy stinks for sure. Obama may not have THE answer, but so far, it’s the only one that makes much sense. So forge ahead we must (besides, if Obama’s economic strategy doesn’t work, computers and “blogs” will be a thing of the past; in 10 years we’ll all be busy outrunning howling gangs with painted faces and Mohawk haircuts, intent on robbing us of our precious gallon or two of petro.)

So, where do we go from here? Well, we’ll likely continue to write occasional rants, as we said, the world and our country are far from perfect. And, we’ll continue our “ecological” bent, but with even more with a focus on how it’s applied to modes of transportation (boats, cars, trains and planes). In fact, for the foreseeable future, we will be writing a number of articles on how you, the budget conscious and/or out-of-work average person, can save money by doing-it-yourself when it comes to “pimping out” (now, in these economic hard times, translated as “making into basic transportation”) your boat, car, train or plane.

Author Max Wilson will be doing a series of articles accompanied by useful “how to” pictures and videos about reviving a once DOA Jeep Cherokee. Also soon to come for those of you that can be described as “nautical escapists”, articles from Captain Jimmy about transforming his 1984 41 foot ketch into something that can actually be used as an “escape pod” (that is, escaping in style, without danger to life and limb). Since The Captain is basically professed escapist himself, it will also include some techniques and projects that might contain just a hint of survivalism (example: “Jerry Cans that can Catch Rain Water”).

So, when all is said and done, “moto” means “motion”, so “motion” it is!

Some of the appealing factors for this purchase were:

1. Laredo edition, this means the Jeep has power windows and locks.
2. NP242 transfer case, this transfer case provides 5 different modes of operation (2WD, 4WD Part Time, 4WD Full Time, Neutral, 4WD Low Part Time) this makes it ideal for highway and off highway use. 
3. The 87 – 90 use the same transmission, we already had one from an 88 Cherokee that we rebuilt. 
4. Body was in good shape with only a few minor dings, paint on the other-hand was in horrible shape. 
5. Dana 30 High Pinion front axle and Dana 35 rear with LSD, both geared at 3.73 gear ratio.
6. Factory Tow package prewired with class III hitch.

The criteria for the build was to create a reliable and comfortable daily driver (DD) that is also highly capable off highway in many different situations, this is not a rock crawler but more of a all terrain build. Because of that the Jeep must ride smooth on the highway yet still have enough flexibility to go over a wide range of terrain. The interior must have most the luxuries of modern vehicles yet still provide the ruggedness you would expect from an sport utility vehicle.

The photo to the right was taken on the first day we got the Jeep, right after the tow truck dropped it in the driveway.

The following series of articles will detail each step of the process building this Jeep from a Junker to a Off Road Machine, we will include many photos and detailed technical information that may help you on your own build. 

Here is the breakdown of the steps:

1. Purchase the Jeep, Transport home, and Register at DMV
2. Create plan for the Jeep, including what hardware to purchase, etc…
3. Rebuild transmission and get the Jeep drivable
4. Sand, Prime and Paint the body
5. Install Rubicon Express Lift kit
6. Install custom Slip Yoke Eliminator (SYE) and new driveshaft 
7. Rebuild the Roof Rack to make it more aerodynamic
8. Strip the interior, install Peel-n-Seal and replace the interior
9. Install the Electronics, Radio, CB radio, and GPS 
10. Drive It

Stay tuned as we will continually update the site with more Jeep Build articles, we will also update this page with links and other information for the series.

Complete Machine.

NOTE: I am currently trying to sell the CNC that is in this article, If you are interested please contact me at Max@9xnet.com.  Thanks for all your continued support!

Building your own CNC Router can be a fun and exciting project. CNC stands for Computer Numeral Control and is used to cut designs that were created in a computer CAD program.

This article will walk you though all the steps in planning, choosing the parts, building and using your DIY CNC.

Computer aided design, or CAD, has always interested me but up until recently I haven’t needed to manufacture parts requiring CAD, , and finding out how much companies charge to mill parts, I decided I would make my own machine to do the job.

My main goals were to be able to cut plastic, wood, and soft aluminum keeping the cost under $750 USD.

To date I have spent around $1041 on the build out of the CNC.

The first step in the DIY CNC is to decide on what plans you are going to use for the build. Will you have a fixed gantry or moving gantry? Are you going to make it out of wood, plastic or metal? What controller board and steppers are you going to chose?

Here is a list of exactly what I ordered for my build:

• 1 Hobby CNC Controller, Steppers kit HCNCPROPKG Hobbycnc.com
• 3 Flexible Spider Shaft Coupling Hub, 1/4″ Bore, 1-23/64″ Od 6408K121 McMaster.com
• 3 Flexible Spider Shaft Coupling Hub, 1/2″ Bore, 1-23/64″ Od 6408K712 McMaster.com
• 3 Buna-N Spider For 1-23/64″ Outside Diameter, Flexible Spider Shaft Coupling Hub 6408K73 McMaster.com
• 12 Black-Oxide Steel Set Screw Shaft Collar, 1/2″ Bore, 1″ Outside Diameter, 7/16″ Width 9414T11 McMaster.com
• 6 Steel Ball BEARING–ABEC-1, Dbl Sealed, No. R8 For 1/2″ Shaft Dia, 1-1/8″ Od 60355
  K36 McMaster.com
• 3 1/2″-10 Acme Size, 10 Tpi, Standard Nut For, Precision Modified-Acme Threaded Rod 6350K41 McMaster.com
• 2 1018 Carbon Steel Precision Acme Threaded Rod, 1/2″-10 Acme Size, 10 Turns/Inch, 6′L, Rh Thread 99030A105 McMaster.com
• 3 12L14 Carbon Steel Tight-Tolerance Rod, 3/4″ Diameter, 6′ Length 5227T28 McMaster.com
• 12 Sae 841 Bronze Sleeve Bearing, For 3/4″ Shaft Diameter, 7/8″ Od, 1-1/2″ Length 6391K207 McMaster.com
• 1 ¾” MDF 4′ x 8 ‘ Sheet Home Depot
• 1 Project box for controller Radio Shack
• 1 Transformer 115 VAC to 24 VAC 10A F-401U alliedelec.com
• 1 Rockliff CNC router plans rockcliffmachine.com

One thing that I did for this build is to order everything at the same time so I am not held back by delayed shipping or other problems that could delay the building process.

Here is a photo showing all the parts needed to get started, the only thing not shown is the threaded rods.

All the parts laid out getting ready for assembly.

The first thing assembled was the stepper motor driver kit. It comes in a bag with what at first glance looks a little scary with all the components just scattered in the bag, but after opening it up you discover that HobbyCNC has written a wonderful manual explaining each and every step in building the driver kit.

Stepper Driver kit, it comes in pieces and requires lots of soldering.

There are a few parts that need to be soldered in place to achieve the right orientation, otherwise they wont work. I made that mistake once and had to de-solder the part and flip it around! You want to follow the manual exactly how its written as there are a few tests that you need to perform before you install the last 3 chips.

Here is my 3 Axis driver kit fully assembled.

All soldered together and ready to test.

I reviewed a number of the many CNC router plans. I needed to take into consideration difficulty of building, cost, time to build it, and what materials it used.

For this build I went with the Rockcliff CNC router plan. It features and fixed gantry 5″ for the z axis and 18″ x 18″ for the x and y axis. There design is fairly simple and easy to understand. I built mine out of MDF. I took the plans to Kinko’s and got them printed at full scale 1″ = 1″, and then glued the plans to the sheets of MDF using aerosol spray can glue.

Template glued to the MDF before cutting.

At first I tried using a jig saw to cut the pieces, but because it’s an inexpensive saw, I was not able to get the cuts to be perfectly vertical. I then broke out all the tools I had in storage; a table saw, power miter saw and circular saw.

Now that I was using the correct tools the process started to go faster and cuts where looking 100 times better then before. Then I started working on the gantry sides. At this juncture all my good luck went bad. After cutting both sides out and putting them next to each other they where not even close to being exactly the same size and shape. If these two sides aren’t perfect the whole machine will not work right.

After a few hours of trying to figure out how to make both the sides the same I had the idea to screw them together and then make all the cuts and holes needed; this worked out very nicely. I then had two identical sides.

I based a few modification from Don’s router (cnczone.com), The Y Axis is bolted down to the table and not part of it, and the gantry support brace is made double thick to add more strength to the machine.

The machine is designed to have the gantry easily removable from the main table by removing the four Allen head bolts from the gantry sides. This allows for servicing and for transportation as the full machine weighs close to 100 LBS.

Hex screws allow for gantry to be quickly removed for transportation.

After the basic machine is built you can start to get a idea of what the machine is going to look like and the scale of it. My machine is about 20″H x 40″L x 25″W and is built using almost a full 4′ x 8′ sheet of ¾” MDF.

Gantry Bolted on.

The next step is to choose an axis to begin construction. I started with the X axis. First you want to cut the steel rod about one inch wider then the gantry. I then slid 2 bronze bearings onto each rod. Its always a good idea to do a test fit of the parts before you glue everything together, so I clamped the X Z plate to the bearings and slid it back and forth. There was some binding toward each side of the gantry so I took the bottom rod out and sanded the holes in the gantry. This minor adjustment made the X axis slide like butter both ways. Now that the axis moved smoothly, I glued the bearings to the X Z plate using Gorilla Glue, then clamped all 4 sides and let it dry for a few hours.

I repeated this step for the remaining two axis.

Test fit of x axis.

The design calls for ¼” – 20 threaded rod for the drive shafts (the 20 after the size means how many Threads Per Inch TPI there is). To try to save money I went with the ¼” – 20 rod, but after installing it I found that it was not strait enough and would whip around on the unsupported ends, and eventually ripped the y axis mount out during trials.

So I then decided I will go with ½” – 10 precision threaded rod, with real motor couplings and bearings for support on each end (this is what caused me to go so much over budget)!

The reason that the Acme precision threaded rod is so good and possibly why so expensive, is that on most standard threads the shape comes to a point. On the Acme, each thread is more squared off. You can see a close up of the acme in the thread tap photo. Because of the square threads it makes a very smooth and precise drive system.

After looking for a good way to mount a nut to each axis, I found one that would work that had a flange and 3 holes in it. What I did not realize is it was made for the precision modified thread, so it just would not go on easily.

I cut the nuts to about one half the original length, as shown.

Drive nut for each axis.

Since I really did not want to have to wait another few days to get a thread tap or new nuts I used some spare Acme rod and used the jigsaw to cut four notches down about 3 inches long. I then sanded it into a point using the belt sander. This worked beautifully as it rethreaded the nuts and they now all spin very freely on the rods.

DIY Thread Tap

So now that the nuts are on the rod I had to fabricate new motor mounts since the Love Joy motor couplings where a lot larger then the previous couplings. I was able to do this my making standoffs that are 1.5″ long. This made room for the new coupling’s but saved me the trouble of having to make all new motor mounts from scratch.

LoveJoy Couplers

It took a little bit of modification to the motor mounts since the new couplings where about 1.5″ long and pretty wide; you can also see how big the drive rods are compared to the ¾” slides. Again I started with the X axis then moved to the Y axis and finally the Z axis shown below.

Motor mounted with LoveJoy coupler.

Showing the LoveJoy and Drive Nut.

One thing that should be noted is that the nuts attached to the wood are temporary; once the machine is fully functional I planned on cutting some brackets that will allow all three screws to be used making a much more sold mount.

So now that you have the basic machine built, it is time to wire everything up to the controller. In my case the stepper motors are 305oz and have 8 wires, the controller board only had 6 wire outputs. This is because 4 of the wires are common/GND. Since each stepper has different wiring you want to be careful in wiring the steppers up so they will run correctly.

To power the Steppers, I originally used two computer daisy-chained power supplies, but after a while of having them both wasting desk space, I ordered a 115 VAC to 24 VAC transformer. This has to be connected to a resistor bridge that converts the electricity to DC and then stores the power in the large capacitor until the power is needed.

Now that all the wiring is done its time to decide what software you want to use,

There are a number of good CNC interpreter programs that are available for $50 – 300 for a license.

I will be talking about the Mach3 program, it runs on a windows computer and will run up to 1000 lines of G-Code in the trial version.

When you first start Mach3 you first need to go in and set the pins for each stepper motor so that Mach3 can send the signal to each stepper so that it will turn in the correct direction. The next step is to configure the Turns Per Inch (TPI) the stepper motors turns at 1.8 degrees per step, so 360/1.8 = 200 steps per full turn.

So now that we know that to make the stepper turn one full revolution it needs 200 steps, and so to move the nut on the Acme rod it takes 10 revolutions. With some simple math, we get 200 * 10 = 2000. But with the HobbyCNC board there is a thing called “Micro Stepping”. I have set mine to ½ so to move the nut one inch I would have to set Mach3 to 4000 steps per inch. The micro stepping can help make the machine more accurate if used correctly.

On the same page that you configure the steps per inch there is a setting called “acceleration”. Now this is a setting that is very important! If the number is set to high the stepper will just stall randomly. I have set mine to 30 IPM on all 3 Axis to get the steppers to work without constantly stalling.

So now that you have the software configured its time to turn the power on to the machine. If everything goes well you should hear a hissing noise from all the steppers this is a normal sound; they also will get extremely hot after being on for a period of time. This is completely normal.

The first thing I did was set the IPM to a very low number like one, and then try to Jog the machine. The arrow keys will control the X and Y axis and the page up/down keys will control the Z axis. So press an arrow key and see if anything moves. If it does, you have configured the software correctly and wired everything up the way it should be.

What I did next was slowly increase the IPM until the machine would stall out; I then lowered the number by 5-10 and set that as a base line for testing the machine.

This seemed to work well and I did not have any stalling problems. Now its time to try to cut something!

I use Alibre Design Xpress to design my CAD. It’s a free program that is very simple and powerful; once you have the design you want to cut you can export it as a STL file or a 2D DXF file.

If you are using a STL file you need to use a program to convert it to G-Code. I have found ACE converter works perfect for this. So now that you have the G-Code you can take that to the computer that is connected to the CNC and open Mach3, go to file > load G-Code. Then move the machine using the jog controls to the point you want as the start, zero the machine and then hit the start button.

If you set the machine up correctly and the software is configured correctly, you should see it cutting the design out. It took me a few days to tweak the machine to the point where I would be comfortable to walk a few feet from the Emergency stop button.

Conclusion

After it was all built and running it was so rewarding to see the motors moving and to hear the wonderful sound of the steppers. And to now be able to manufacture prototypes for my products is just awesome!

Would I do it again? Definately (even though it came out over budget by a few hundred dollars). In the end, the upgraded Acme rod is what ended up making or breaking the system. It was also a great learning experience to discover what power tools work for what and what don’t.

I look forward to cutting designs and products for a long time to come on this home-built machine.

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