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Machinist Toolbox – What To Buy?

Are you new to the Machining industry or considering a career in this field of manufacturing? A toolbox is one of the first things that you should buy. It’s where you will keep most if not all of your tools, personal inspection equipment, and books/manuals such as the Machinery’s handbook.

Kennedy tool boxes are well known in the Machining industry because they are well built and have been around for 100 years now. If you’re looking for a tool box that is made in the U.S.A., a Kennedy is the way to go for a new Machinist, whether it’s a top box, or a bottom as well. These boxes are made specifically for Machinists, so the length, width, and depth of each drawer is designed for specific tools, allowing you to easily organize your set-up; and we all know that time is money when running CNC machines.

Kennedy Top Box
Kennedy Top Box

If you’re on a budget, a standard tool box can work just about as well. It may not be built to hold your machining tools as well, but you can find good deals on sturdy boxes that will save you money for buying even more tools!

There are also some Machinist knock-off tool boxes are on Amazon for a fraction of the cost, such as this 11 Drawer Roller Box. Due to its low price, it won’t have the same quality as say a Kennedy, but some of the same features are there with a similar layout. Like most anything these days, you generally get what you pay for. For something such as a tool box, if you’re a rookie machinist, then a cheap box may work just fine.

What To Look For?

If you are just starting your CNC Machinist classes at the local Tech school and had to buy a tool box without doing any research then it probably won’t make much difference at first. After going to school or working for some time, though you’ll realize what you want in a tool box, and even that may change after being on the job for years.

Size is the biggest factor when purchasing a new tool box. Obviously if space is unlimited and you don’t plan on transporting it often or ever, then the bigger the better. If you buy a big box right away then you won’t have to upgrade right after buying a handful of new tools. On the flip side, if you don’t have many tools then you’ll be pushing around a lot of dead weight if you move around the shop on a weekly or daily basis.

If you have a chance to look at and test out tool boxes in person, I would suggest looking at and opening the drawers to see how smooth they are.┬áBall-bearing drawers slide out nicely compared to the conventional slides. This feature isn’t necessarily a deal breaker, but it’s always nice to have things that perform better.

Castors are the wheels used on tool boxes and are another feature that should be considered when doing research. Putting a lot of heavy tools in your box will put more strain on the castors, so it’s good to have big and sturdy castors.

If you still can’t figure out which one to buy, there’s nothing wrong with having one, two, or three boxes to choose from.

A quick tip on how to prevent tools from getting nicked and scratched up after constant opening and closing of drawers; tape a sheet of felt or lay a thin rubber mat down in each drawer for padding and to help prevent everything from sliding around.

Tool Runout vs. Tool Deflection – What Are The Differences?

There’s a reason tight tolerance parts cost more time. Yes, I use the word “Cost” because time is money, and it can take a considerable more time to set-up and run a part if the tolerances are closed up. Tool run-out and tool deflection can both be an issue when trying to hold a close tolerance. However, they are not the same thing.

Run-out

Tool run-out is how far off of the rotating axis the tool is. While in the machine, you want to check just above the bottom of the tool, as that will give you the most accurate reading and is almost always worse than the top of the tool where it goes in the holder. To check it, put an indicator on a vice and touch the tool off of it. Zero it out and then rotate the tool (usually in a counter-clockwise rotation so it doesn’t catch the cutting edge). If there’s run-out, one side of the tool will give you a different reading on the indicator.

Before we go any further, let me explain what run-out actually does when machining a part with a tool that has it. If an end mill or a drill has excessive run-out, the side (or flute) that is bigger will do more cutting. If you’re milling out a hole with an end mill, it will cause the hole to go over-size if all of your program and offset numbers are right. A drill can also go oversize, as well as drill an oblong hole.

Now lets take a look at what causes a tool to have run-out. A brand new and unused tool can have run-out. Why? Not all tools are made the same, and if you buy cheap tooling, there’s a better chance that it was made with the same precision as a higher quality tool.

Not only can the tool be at fault, but a defective tool holder can cause run-out as well. On the other hand, you may check the tool while in the spindle and see that their is run-out, but certain tools (such as a reamer or drill) will allow you to slightly move it without removing it. This can often get rid of many run-out problems with longer tools.

Tool Deflection

Tool deflection should not be confused with run-out. It is a common term used when side milling with an end mill, and it causes a taper in the part feature that is being milled.

Take this as an example; you’re milling the outside profile of a part (2x2x2.25″) that has blueprint dimensions of 1.950″ wide, long, and 2.000″ tall. Using a 3/4″ end mill with greater than 2 inches of flute length, you mill around the part once. The top of the part is 1.951 all the way around, but the bottom is upwards of 1.954″. This is because the end mill is too long and was ‘deflecting’ because it couldn’t handle the pressure of removing all of that material.

That’s the most simplistic scenario of tool deflection. So, how do I combat this? Great question, and there’s quite a few ways to make sure your part is square, perpendicular, and/or parallel.

First of all, how deep of a cut are you taking? If you’re drilling a 1/4″ hole that’s .375″ thru, you don’t need a jobber drill with 4″ of flute length. When milling, a bigger diameter tool will be stronger and resist deflection better. If you’re milling a feature that is .400″ deep, using an end mill with 1/2″ flute length will achieve the best results. One last thing on tool length is that you should have the tool as short as possible in the holder. Do not clamp on the flutes, but if you choke up on the tool, this will also help prevent deflection.

Feeds and speeds. I’ve said it before, and I’ll continue to say it. Having the right RPM and feedrate for your tools is one of the major keys to success in the Machining industry. Even if the surface foot is close, having a high feedrate will naturally produce more tool pressure and in turn cause deflection.

Slowing down the feedrate can help, but in the end, you may have to take multiple passes to make a feature square, especially if you’re profiling out a part with an end mill.

 

How To Get Fired/Hired On Your First Week As A Machinist

Starting or transitioning to a new job can be difficult. New people, different machines, new shop, and a different way of doing things (to an extent). If you’re already hired and can actually do what you put on your resume, it’s not very likely that you’ll be fired in the near future. That is, unless, you have the same routine at every job. Allow me to explain…

It is easier to train one guy to work like the other 20 machinists, than to train the 20 to work like one machinist. If you already have a way of doing things as a machinist, be prepared to change it up a little bit. Just because you learned how to do something at your previous job or jobs, if your new company does it a different way, YOU are the one that has to change.

A company is not going to change how they do things just because that is how you learned it. One of the quickest ways to get fired is by disagreeing or trying to force your own techniques onto the new shop. Unless they are very open to new ideas and strategies on how to manufacture their parts, they will only keep you so long.SCCCNC1.JPG

So, how do I keep my job after the first week or even month? By working with them and doing things how they want done. Now this doesn’t mean that every technique has to be the exact same, but the process and finished part should be identical. If you think they are doing something wrong or less than efficient, politely suggest to them how they could improve, and ultimately, save money. If that doesn’t catch their attention, then so be it; either deal with it or move on.

If they have a improper machining practices and aren’t willing to accept any better methods, then maybe it’s not so bad that you find another company to work for. It’s often hard to find out how a company operates during one short interview. You don’t really know how they do things until you start working with them.