Plans, projects and how-to's for home machinists

My Lulzbot Mini

My Lulzbot Mini with LED strip lights that I added. The object on the bed is half of an exhaust adapter for a laser cutter.

I started the Rochester Makerspace more than 2-1/2 years ago. It’s a non-profit (501c3) community workshop and art studio in Rochester New York that provides low cost access to sophisticated tools, teaches classes, organizes events, and hosts school field trips.  The makerspace has many very hard working volunteers but it’s still a nearly full-time job for me.  It’s also unpaid one so I also have a very demanding full-time day job.  That’s why this website has been so dormant.

Ironically, I don’t get a chance to make anything anymore because I’m so busy all the time.  That was really starting to bother me so last spring so I bought a Lulzbot Mini 3D printer.  It conveniently sits in my home office so I can make something once in awhile.  It’s a great machine and I want to to tell you about it in case you’re looking for a really good “hobby-class” 3D printer.

The Lulzbot Mini costs $1350, which makes it one of the more expensive 3D printers in its class.  But I think it’s worth the extra cost.

  • To get a high quality 3D print your bed needs to be perfectly level and your nozzle has to start at the proper height about the bed.  Most current machines (all?) require you to make those adjustments manually and you have to periodically redo them.  The Lulzbot eliminates that chore because it has a self-leveling bed.  It measures the height of the four corners of the bed before every print and then automatically compensates if it’s not level. I won’t try to describe exactly how it does that but trust me, it works great.
  • Most printers also have a problem with getting ABS plastic to adhere to the bed consistently.  So their owners resort to all kinds of tricks, like using hairspray, glue sticks, large skirts, or a mixture of acetone and plastic. Many people avoid the problem completely by only printing with PLA on a layer of blue painter’s tape.  The Lulzbot Mini doesn’t have this problem because its heated bed has a layer of PEI. It’s a plastic that ABS sticks very well to when it’s hot and comes off of fairly easily when the bed cools down.  As a result I print almost everything with ABS because of its extra strength and durability and because it’s just so easy with the Lulzbot.
  • I also bought the Lulzbot because I wanted to be able to print with Nylon, which is something most 3D printers can’t do.  The Mini can do it because it has an all metal extruder that can reach the necessary temperature.
  • The Mini also produces very high quality prints.  I’m not sure I remember correctly, but I think it came in second in Make magazine’s latest 3D printer tests.  It’s also super easy to use.

I also think the Mini is very well designed and durable.  It’s also an open source design and you could download all the files and information you need to build one from scratch.

There are a couple of things that I don’t like about the Lulzbot.  It’s too noisy when it’s running.  The Rochester Makerspace has a couple of Soldoodle 3D printers and a Rostock Delta we built ourselves and they are almost as quiet as a whisper.  I also think the cost of some of the Mini’s replacement parts are too high.  The two parts you’re most likely to need to replace someday are the cooling fan on the extruder and the PEI on the bed.

The Mini comes with a one-year warranty and I know first hand and from others that the company provides very good customer support.  The PEI on my bed was badly damaged by someone who used a screwdriver to pry a print off of it when I wasn’t looking.  I needed to fix it within 2 days for a demonstration and the company very nicely agreed to ship a replacement overnight at no extra cost.

If you don’t know what you can make with a 3D printer then check out Thingiverse.

I’m not sure when I’ll be able to contribute something else this to this website.  The Makerspace is getting closer to being able to hire some staff members, which will make my life easier.  I may actually be able to do some machining again.

I want to thank Mikey and Roger for continuing to help visitors to this website who have questions or need advice.

Wrench/Hammer Combination Tool for Mini Mill

By Roger Leete

This tool was made for my Grizzly G8689, but it can be adapted to almost any mill.  Just choose the right sized socket for your particular drawbar.  Note that I did not come up with this idea, but found it on the web.  I made the parts based mostly on the materials at hand.  Dimensions are mostly made up on the spot, and measurements were all made with a scale.  In other words, this project requires no careful measurements or has any critical dimensions.


First step is to find a deep well socket that fits the drawbar.  For my mill, that means 17mm.  I bought sockets at Harbor Freight, but just about any cheap deep well socket will do.  HF has them for about 2 bucks.  As you can see from the pictures below, I cut about 1/2-inch off the drive end, simply parting it off at the line on the socket.  (Some sockets have a different appearance, so roughly 2-3/8-inch long) This dimension is by no means critical.  I was worried that the sockets may be hardened, but a standard HSS parting blade cut it cleanly and easily.  This operation was done on a 7×12 mini lathe, so it’s not like you need an expensive machine to part off.  When you break through to the square bore it will be an interrupted cut, so take it slow at that point, or finish with a hacksaw.   Tip: get or make a carriage lock for your lathe.  It makes parting so much easier.

Next operation was to bore out the square drive hole.  Once again, this was done on the lathe.  The square hole makes for an interrupted cut, so take it slow and easy until you get it round to avoid too much impact on the tool bit.  Drilling first may be easier, to remove the bulk of the material.  You want to bore it out enough for the inner filler piece, but leave enough wall thickness for strength.  My bore is about 5/8-inch diameter, but this is not critical either.  I purposely made the bore tapered slightly.  I’ll explain why in the next step.  Set your compound over a degree or two, and bore it out to size.  The socket machining is done for now.

As purchased on the left, machined on the right

Next piece is the inner filler.  I made mine out of brass for weight, and because that is what I had on hand.  Steel would also work, but I’d not recommend aluminum as you want more mass.  This piece is slightly tapered the same as the bore.  The reason for this is to have it jam up into the socket to facilitate tightening of the hammer head.  Once turned to size, drill and tap for the hammer head screw.  I used 3/8-16, but 1/4-20 would work just as well.  You want enough thread to hold securely, but if you go too deep, you’ll be tapping into the side of the screw when you make the handle.  Using a hacksaw, cut a screwdriver slot in the opposite end. Continue reading Wrench/Hammer Combination Tool for Mini Mill


I feel like I have three full-time jobs. In addition to my day job and I’m working another 20 to 30 hours a week trying to get a nonprofit makerspace started in Rochester NY. My wife and I are also taking care of her father, a widower, whose needs constant care because of failing health. And we’re helping to take care of a daughter and her family. She’s just had surgery for the second time this year to repair a heart valve.

So I’m tired and stressed, but not nearly as much as my wife, who shoulders most of the burden of taking care of family members. I help too, but I mostly take care of our pets and our granddaughter. She is a genuine saint because but she has continued to be very supportive of the makerspace. She understands that I can’t stop working on it because many people are now counting on me to follow through with what I started.

I launched the website for the Rochester Makerspace in mid-May and we now have many supporters, seed money, tools and a dedicated group of volunteers. We still haven’t rented a space but we’re actively looking for the right one. I expect that our doors will be open within the next couple of months and maybe as soon as a few weeks.

I’ll be even busier for a while when that happens. Although I expect my workload to taper off as we figure out the best ways to manage the space. The health problems of my father-in-law and stepdaughter will also end.  So there’s a good chance you’ll see me regularly working on MachinistBlog again someday.

If you’re wondering, the CNC router I’ve been building for more than a year is still not finished, although I’m continuing to work on it. I obviously don’t have much spare time and when I do I’m usually so tired that I’m either unproductive or I make stupid mistakes.

But I’ll bet money that it’ll get finished because it’s going to have a home in the makerspace and there are others who will help me with it.

Thank you Mikey and Roger for answering the questions that Machinistblog’s visitors leave in the comments or on the forum.

There just aren’t enough hours in the day

I know I haven’t added much content to MachinistBlog lately. I haven’t lost interest or permanently abandoned my self-imposed goal of trying to add at least one new post to the front page each week (on average). It’s just that I’ve been really busy and I have to make this web site a lower priority for now.

I’d love it if you could help me keep it from getting stale by becoming a guest blogger. You can write about almost anything that is metalworking, tool, or workshop related as long as you’re not doing it to promote a product or service. And don’t worry if you’re not a great writer because Nate, our copy editor, just told me he needs more to do. You could also do a photo essay if you want.

I’ve been busy for a quite a few reasons. The biggest one is that I’ve become very passionate about getting a maker space started and I built a web site for one. still has a lot of rough edges and it needs some more meat on its bones. So I wasn’t planning on publicly rolling it out this week but that’s what I did when a discussion about maker and hacker spaces came up in a discussion group I run. And now, ready or not, I need to keep moving forward with the project until we either get something going or determine that there’s not enough interest right now.

I’ve also been busy working on my CNC router again. I neglected it for at least several months and I wasn’t happy with myself for letting that happen. So I’ve been trying, not always successfully, to get at least one small thing done on it each day.

On most days I only have enough spare time to work on either it, this web site or some other project. I usually choose the router because I want to be someone who does things and not someone who just talks about doing things. I’ve finished making nearly all the parts for it and pretty soon it’ll just a matter of putting them all together, like a kit. So you should at least see some pictures of it later this month.

I’ve also been trying to find 6 hours each week for exercise. I ran or biked regularly until about 2 years ago when I quit almost completely because I was too busy with other things. Well, in early December I realized that I felt like crap, looked like crap and was risking serious health issues because I wasn’t exercising.

So I started going to the YMCA 3 times a week and mostly just walked as fast as I could around an indoor track. But it made a big difference in how I felt and a few months ago I started running again.

I’ve been a runner almost all my life but I gave it up about 5 years ago and switched to bicycling because I was afraid running would eventually ruin my knees. I’d never had any problems or injuries but I’m very tall so I already had a poor power-to-weight ratio to begin with, and like most people I was getting heavier as I got older.

But bicycling didn’t do it for me and I really missed running, especially each Spring when the weather began to get warm. So I pre-registered for my favorite 10K and started training on treadmills and cinder tracks because they put less stress on your knees than pavement.

Five years ago I could go out for a long fast run and it wouldn’t affect me very much afterwards. But that’s not true any more because I’m still out of shape, still at least 10 pounds heavier than I used to be and of course I’m older. Now a hard run can ruin me for the rest of the day, tiring me out so much that I spend my evening goofing off instead of trying to accomplish something useful. Hopefully I’ll get into better shape soon and that won’t be as much of a problem.

And finally, the arrival of warm weather brought more opportunities to spend time with friends and family. And I’ve always made doing that a top priority.