MAKER MOVEMENT PROJECTS

Dirty Little Secret – How To Make Your Own CNC Milling Machine

Written By: Bill Griggs - Jul• 29•14

Dirty Little Secret

Part 2

Dirty Little Secret

When I decide I wanted to learn how to make your own CNC milling machine, I asked some friends for advice. All of these folks owned machine tools and as I talked to them a dirty little secret emerged. Knowing about this sordid tale is crucial to your success. What is the Dirty Little Secret? Well pull up a chair and I will do my best to tell you.

The dirty little secret of how to make a CNC Milling machine is also true when owning any machine tools. The Dirty Little secret is that you spend as much on tooling and accessories for the machine as you do for the machine itself. There. I said it. I’m glad it is finally out in the open.

I didn’t know this dirty little secret when I bought my first milling machine but I know it now. Now that I know this secret, I could factor it into my budget before I ordered my milling machine. Having a good idea about how much the total project will cost, is essential and can help you make a better purchasing decisions.

Plan Your Tool Order

Some people choose to buy their tooling in stages, a bit at a time. Well, buying your tooling in stages can actually slow down your projects. I remember when I bought my first milling machine I had not planned well and could not afford to buy a machining vise for several months. That delay cost me time and money because the machine sat idle. So a little planning can help you focus on what equipment you are likely to need, in which order and also decide which equipment are luxury items you can purchase later or do without.

To plan out my tooling budget my first step was to decide to have a budget. Knowing how much to spend before hand can help you focus on cost savings and prioritizing. Since I knew the secret, I was able to establish the cost of the milling machine as the basis for machining purchases. The milling machine cost roughly $1400 so I figured that would be a good place to start. I had one advantage that most people starting out would not have. I already owned a milling machine.  So first I looked at the tooling I already owned. Since I had many tools and accessories for my Harbor Freight Mini-mill I figured I could use many of them with the new mill and sell those I didn’t need along with the mini-mill to cover my costs. Next, I  thought about what types of machining I was likely to do first. This let me focus on which tools I needed right away and these tools got moved to the top of the list. Then I looked at which tooling and fixtures I didn’t have but still wanted.  Since both my milling machines used R8 collets and I already owned a collet set, I decided not to buy a conventional collet set for this mill. I did however want to make tool changing easier and faster, so I looked at the TTS system from Tormach. http://www.tormach.com/

 Tooling

Tormach

Tormach TTS starter set. Copyright Tormach LLC

When I chose the Grizzly G0704 I knew it matched the R8 tooling I had with my Harbor freight Mini-Mill. Not having to buy all new tooling saves me nearly the cost of a Mini-Mill. Having an R8 tooling spindle will also allow me to use the  Tormach TTS tooling system  in addition to the R8 tooling. The TTS System consists of a specially shaped R8 collet and a series of specially designed tool holders that fit the collet. Because of the way the tool holder is machined, each one fits the spindle in a precise, repeatable  way. Many Makers are using the TTS system tool holders as a basis for an automatic tool changer. A starter set is available for around $190. There are also several vendors who make compatible tool holders which fit the TTS collet. I talked with some machinist who had tried these off brand holders and got good reviews. There is also a video that teaches you how to make your own holders if you like. I ordered the TTS set from http://littlemachineshop.com

 

Mobile Base

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Shopfox Mobile Base with leveler feet.

I ordered three things  at the same time I ordered my G0704. One other thing I ordered right away was a mobile base for the machine. Most of the tools in my workshop are on wheels so that I can easily rearrange the tools when I need them or roll them out of the way when I don’t need them. The base I got was the Shop Fox Mobile Base G8683. It includes a set of leveler  feet so the machine would be stable while milling.  I also ordered a Vice from http://Shars.com. The vise is a 4” CNC vise which is flat on all sides so that it can be mounted upright or on it’s side. The vise is a lock down vise. That means that as the vise is tightened  the workpiece is clamped with a downward pressure and locked in place flat with the vise face. I also ordered a set of step blocks from Enco tools http://use-enco.com.

I decided to ask around for help before ordering any more tooling. I knew several machinists who happened to belong to my Facebook Group so I asked them what they would recommend. The guys came through with flying colors. I compiled a list of all the tooling based on their recommendations.  I took the list and created a link to Amazon so folks could save the hassle of searching all over for the information. You can use this list as a guide and add or subtract items to suit your need. If you would like a PDF version of the list click here. If you would like to join my Facebook group click here.

TOOL BUNDLE

Disclaimer

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