The Apartment Workshop Series: Mini Mill

I’ve been thinking about getting my own mill for several years. I just like the idea of being able to shape metal. For the type of odd ball projects I like, I end up making a lot of my own parts, or customizing off the self ones. Having a mill allows me to do that easier and with much greater precision. I briefly looked at 3D printers, but parts produced on them have such low mechanical strength they really aren’t suited to my projects. Plus I like the idea supporting subtractive manufacturing (milling), as all anyone ever talks about is additive manufacturing (3d printing) these days.

Picking a mill can be a daunting task. There are so many factors to consider: price, working envelope, CNC or manual, construction, spindle type, etc. Being that I planned on operating this inside my living room, my options quickly narrowed. After much research I found several machines that fit the bill:

Little Machine Shop 3900 Solid Column mini mill

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Taig Micro Mill

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Sherline 2000/5400

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The taig and sherline are a closer match, as the LMS mill is more of a mini mill, while the others are more micro mills. The LMS mill was my favorite due to the much heavier construction, more powerful motor, and standard r8 spindle. However it is just slightly too large, on it’s own it is not that big, but when you factor in that it will need an enclosure (which is kind of a must have if you plane on running a mill inside your house) it just get’s too big.

Between the taig and sherline, I prefer the taig. It’s heavier steel construction make it much stiffer than the all aluminum sherline. Neither one will handle steel all that well, both can easily do plastic, but for aluminum the extra rigidity of the taig helps reduce chatter.

I was all set to buy a taig, but I came across a deal I could not pass up on craigslist. I got a sherline 2000 CNC ready mill, with steppers for less than 1/3rd the retail price. Whoever was using it last was cutting wood, as there are wood particles all over. It will need to be disassembled cleaned and lubed before use.

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It fits very nicely on my workbench, and even when an enclosure is added it should not hog too much of the work surface. It did not have a control box, so I’ll need to start looking at stepper drivers, power supplies, and machine control software. Looking forward to this!

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The Apartment Workshop Series: Workbench

Due to a job change I no longer have access to the plethora of tools at my old job.  While there are some local hackerspaces, I really like having access to equipment whenever inspiration strikes, rather than having to wait unil the hackerspace is open (also working in your boxers on a Saturday morning). So I am setting up a small workshop in my apartment living room, were I plan to do everything from soldering to machining. This will be the first in a series of articles showing how I setup  and fill this space with various toys.

Every good work shop starts with a good workbench. My money-is-no-object bench would be a Lista cabinet with a maple butcher block top.

18733s3.tifUnfortunately these are disgustingly expensive when bought new and, unless you get lucky on craigslist or an auction, they are still expensive used. My goal is to replicate the Lista bench, but for an order of magnitude cheaper.

One of the first things you should do when designing a workbench is to think hard about what you will actually be using it for. A bench designed for SMT electrical work is a lot different than one for taking engines apart. I plan to use my bench for tool storage, some soldering/electronics, parts storage, machining (once I get a small mill and lathe), light assembly, and taking things apart. I took each of those tasks and figured out what requirements they would impose on my design.t

For tool storage (specifically, hand tools) the Lista cabinets are great as the many thin drawers allow for an enormous amount of storage in a small footprint. Lista cabinets are very similar to rolling tool carts found in garage shops (minus the caster wheels), so that’s where I started looking. I spent several hours researching rolling tool carts on garage journal and reached several conclusions. If you’ve got the money, tool truck boxes (snap on, matco, etc) are hard to beat. They offer the best construction, but at a hefty price tag. Surprisingly, Craftsman tool boxes were generally regarded as the worst quality, people described them as having thin gauge sheet metal, and really bad drawer slides. Also surprisingly, Harbor Freight tool boxes were said to be the best tool box for your money, decent quality, but still affordable.

I ended up getting Harbor Freight item#67831 and selling off the top box to recover some funds. Make sure you get the 26″ model, the brownish 30″ one is much lower quality.

With the tool storage figured out I started looking for a work surface. I like working on wood, as I can sand down and refinish it when it becomes too loaded up with crud (it also looks nice). I went looking for a low cost alternative for the maple top on the Lista bench, and found the Numerar series countertops from Ikea.

It isn’t as deep as I’d like (25″), but the construction (almost 1.5″ thick beech!) and price were spot on. I ended up getting the longer 96″ version, figuring I could always trim it down and use the extra as a lower shelf.

Next up were finding sturdy legs. I considered using wood 4×4 posts, but since this is in my living room and very visible, I wanted it to look a little nicer. I chose speed rail fittings and 1 1/4″ sch 40 aluminum pipe, as they are very strong, but gave it a slightly industrial look. I later found out that McMaster has a nice selection of pre made work bench legs, some with cut outs for electrical outlets.

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For medium sized parts storage I wanted to utilize the area under the work surface by hanging pull out drawers. Since I don’t have access to a cabinet shop to make custom drawers, I came up with my own solution. In my experience work bench drawers usually end up as a disorganized pile of random parts you don’t know what else to do with. Since the drawers are just one large space everything ends up mixing together.

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My solutions to this was bins with a divider grid system. These bins are dividable down to spaces 1″x1″, allowing for the creation of all sort of odd sides compartments. They also come in a variety of depths and colors, and are stackable.

The drawers slides ended up being one of the harder problems to solve. How do I hang these bins on the under side of the work surface? They have a large lip, and sloped sides so I couldn’t just attach off the self drawer slides. I considered building a self underneath that they could rest on, but interfacing with the speed rail was problematic. I really needed a bracket that the bins could slide on, supported by the lip that runs along the outside. If you know machine tools think of it like box ways. I initially thought about making my own from aluminum square tubing, but that would have been a lot of machining time to cut all the slots and holes (I needed to make about 8-10 slides).

I was browsing McMaster one day and found this aluminum extrusion that is normally used as trim around panels. It has the perfect shape to function as a slide, but still allow me to have a spot to screw it to the underside of the bench.

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With all the parts acquired I could start putting it all together. I first layer out the hole pattern for the leg fittings, insetting them slightly for appearance.

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3/16″ clearance hole for a 1/4″ lag bolt.

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The drawer slides came next, I drilled and counter sunk holes for  #8 wood screws. I had to counter sink them as the drawer would hit any fastener proud of the surface when pulled out.

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Aligning and spacing all the slides.

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Here’s the almost finished bench. I put on several coats of tung oil to act as a sealer, turning it a golden color. After this was taken I also added an additional leg in the center towards the front, as it needed a little more support mid-span.

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I ended up using the full length of the counter top material since it fit in the space and you can never have enough work surface.

If you’re curious here’s a few shots of the drawers filled with parts.

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Modern Dining Table Part 3: The Conclusion

Part 1 and Part 2 here.

This weekend I wrapped up my modern dining room table project by installing the legs. Rather than 4 individual legs, I chose two trapezoid shaped metal frames on each end.

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This table won’t have an apron, which gives rigidity to a table. Think of the point where the table attaches to the legs as a hinge. The further away from the hinge that the leg is supported the more rigid the connection, so apron = good, stretcher = better.

With a leg configuration like I have you’d normally need a stretcher between the legs to prevent the table from wobbling side to side.

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How to make a stable table. able.

To eliminate the need for a stretcher, the flanges where the top connects to the legs were made extra wide by adding a piece of 3/16″ angle to the steel tubing.  1/4″ lag bolts secure the legs to the top (pre-drill so you don’t split the wood!)

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I wanted some contrast between the legs and the warm natural look of the reclaimed wood table top. Rather than paint the legs I had them clear coated, allowing the welds and tube seams to show through.

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I need to put some felt pads under the legs to protect the floor, but other than that I’m going to call this one done.

Suppliers:

Wood table top: http://www.americanmaad.com/tables

Legs: http://www.etsy.com/shop/TRRTRY

Modern Dining Table: Update

After not so patiently waiting 6 weeks for our table top to arrive, it is here!

As a side note, I am continually impressed at what a Prius can fit inside it.

It looks great, full of old nail holes, and patterns from the huge saw blade in the mill where it was cut many decades ago. It’s currently sitting on the cheapest saw horses I could find (Ikea, $15 on craigslist). As you may have seen in the first post, I had originally planned on making trapezoidal shaped legs from 3×1 rectangular steel tubing. However I recently came across another table that used machine stand legs from old factory equipment circa 1900:

 

Cast iron, 24 x 29 1/2 inches

 

There are a few issues with using them: hard to find, expensive (even more so to ship), and super heavy. I think I can replicate them in 3/16″ cold rolled steel which will address most of those issues. The only draw back is the texture of the metal. The originals are cast iron which has a rough textured surface from the sand it was cast in. The steel is very smooth. I’m going to see if there is some type of process I can perform on the steel to mimic the look of cast iron.

Of course switching to these legs will make the table decidedly not modern, so maybe I’ll just call it an industrial table.

Modern Dining Table: Part 1

I’ve started designing a dining table for our new apartment. I really like the aesthetic of reclaimed wood and steel tables, unfortunately a pre-made table like this costs in the $1500 to $3000 range. Way more than I can spend on a table. The designs are very simple and I figured I could make one myself. After some digging I found a local shop that will build the table top out of reclaimed douglas fir. The legs are designed by me and will be either made by myself (pending purchase of a TIG welder) or will be sub-contracted to a fabrication shop.

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