Choosing a laser cutter for a makerspace

We’ve just picked a laser cutter for the Nolop makerspace at Tufts. I thought it would be useful to record how we made the decision. (Spoiler: we’re getting a Universal VLS 3.60.)

The first advice I got repeatedly from every experienced makerspace manager that I talked to was that I should prioritize reliability and ease of use over cost because university makerspace users are often new to laser cutting, which means they need help a lot, and they accidentally break stuff.

There are two large categories of laser cutters you can buy: cheap lasers with glass tubes made in China (including those imported by Full Spectrum Laser and Boss Laser) and expensive lasers made in the US. The latter category consists of three companies: Epilog, Trotec, and Universal; their lasers are 2-3x more expensive than the lasers from China, but they have better customer support, and their software is not hard to use or buggy.

I surveyed my senior mechanical design class on the sizes of the parts they had cut during their college careers (mostly using the Trotec Speedy 400 laser in the mechanical engineering shop). They estimated that of the ~450 parts they had cut, only 5 were larger than 12″ x 18″. This pushed us towards the smaller, cheaper lasers, especially given that students can use the larger laser in the ME shop if they need to.

Then, I thought about optimizing for the greatest average throughput. Cutting speed is roughly linear with laser power, but less than half of the cost of a laser cutter is for the laser itself, and the cost rises less than linearly with power, at least for powers in the 10-100 W range.

We got quotes from Universal and Trotec for a few different sizes. (Epilog’s Fusion M2 series would have been in the running as well, but they’re large and thus relatively expensive.) For the smallest-bed laser that could accept a 60 W laser, this pitted the Universal VLS 3.60 at $21k against the Trotec Speedy 100 at $30k, so we opted for the Universal. The stop at 60 W was arbitrary, but getting a more powerful laser from Universal would require moving up to their PLS series of professional laser cutters.

One other feature tilted us toward Universal: the laser head has a feature where it can pop loose when someone bumps it, rather than breaking a belt or stripping a pulley.

We have workbenches and a saw

Last week, a truck filled with 15 square workbenches and 7 long tables arrived from Steel Sentry in Texas.

Each bench is 4 x 4 feet, so we can make a 4 x 8 work surface or two smaller ones. The bench height is currently set to 34.5″, but the legs can be adjusted up or down a few inches with a wrench. The benchtops are 1.75″ thick, and they stick out past the frames by 4″ all the way around. Our hope is that they’ll make clamping stuff easy. Each work bench cost $1062 and the long tables were $1412 each, so the total for benches and tables was around $25,000, plus shipping.

Workbenches in the assembly area

We ordered 15 workbenches, so the total area devoted to benchtops is 240 ft2, or roughly 5% of the total area of the 5000 ft2 makerspace. We have another ~100 ft2 of long tables that will hold equipment like 3D printers and oscilloscopes.

The table saw also arrived last week. It’s a Sawstop ICS53230 with a 36″ fence, powered by a 5 hp, 3 phase, 230 V motor. The total cost, with the fence and delivery, was $4649.

The table saw coming in the front door

Next up, a laser cutter and 3D printers!

Our occupancy has been certified

Yesterday, the cities of Somerville and Medford granted us certificates of occupancy.

The eventual site of the Byrne Advanced Machining Area. (Thanks, Dan!)

Looking down the space toward Byrne

The digital fabrication area and the entry to the space, the latter funded by the Stricker Family

The ceiling is up

The ceiling is up; the first round of taping and mudding the drywall happened today. Some parts of the space have been painted. Note the brilliant orange entrance to what will eventually be the digital fabrication area.

The walls are closing in

A little more than half of the insulation and wallboard is complete in the new makerspace. The shot below is what will eventually become the Byrne Advanced Machining Area.

The space through the opening pictured below will be devoted to modern digital fabrication, meaning machines that are guided by computer models rather than by the human hand. The typical examples are 3D printers and laser cutters, but we may also add vinyl cutters, a small computer-controlled mill or waterjet, or similar tools for working with textiles.

The sheetrock has arrived

Most of the steel studs have been screwed into place, and some of the insulation is up. The next step is to cover the studs and insulation with gypsum wallboard.

At the same time, the air ducts for heating and cooling the space are nearly complete, the plumbing is done, and the electrical work is mostly done.

After the air ducts are finished, a drop ceiling covered in acoustically insulating foam will be installed, so the noise of the workshop won’t annoy the people upstairs.

Wall framing underway; workbenches ordered

Last week, the ceiling was fireproofed, and now the walls are getting framed with galvanized steel studs. At the same time, electrical contractors are roughing in the outlets and wiring in the ceiling, and the HVAC people are hanging ducts from the ceiling. Most of the ducting, plumbing, and wiring will be sandwiched in between the fireproof ceiling and a lower soundproof ceiling that will be installed in a few weeks.

The basic infrastructure schedule has slipped about a week, so we’re now expecting walls, electricity, plumbing, heating, and such to be done on September 26.

Our big furniture order has been placed; we’re expecting some to show up in September, but the big set of work tables is scheduled for approximately October 16.

We’ll be having our first public event for Parents and Family Weekend on October 19-20. We might not have many tools up and running by then, but the doors will be open!

Second layer of concrete

The second layer of concrete was poured Friday afternoon, and it has now cured enough to walk on. Eventually, there will be "luxury vinyl tile" over the concrete, but not until the rest of the heavy work is done.

Next up is relocating some of the large white water pipes on the ceiling to make way for the new HVAC system. This means shutting down air conditioning for all of Robinson Hall until the pipes are reconnected. Sorry, everyone!

The floor exists.

The first layer of the concrete subfloor of the makerspace is getting poured today. The black goo at the left edge of the photo is sand-impregnated epoxy that acts as a moisture barrier and gives the concrete something rough to adhere to. The white sheets are fiberglass mesh that will increase fracture toughness, i.e. it will allow the floor to flex more before it cracks.

The floor for the whole space will require around 32,000 lbs of fiberglass-impregnated cement, plus around 1600 gallons of water that will evaporate over the next few weeks. About half of this will get pumped in through the window today; the second half will get pumped in Friday.

Next week, framing begins!

Below, the concrete mixer and what should be ~800 bags of concrete.

The concrete mixer and what should be ~800 bags of concrete

Concrete progress

Here are some photos of the stripped down shell of the first level of Robinson Hall, which will become the Nolop makerspace over the next 6 months.

The photo above shows the digital fabrication area, for laser cutters, 3D printers, and similar stuff. All the lead paint and asbestos has been removed. The red shape on the floor marks a thin section that will have to be jackhammered out and repoured before the rest of the floor.

The half-windows on the left side look out into the Kindlevan Cafe, above the art wall in the SEC atrium.

In the photo below, we’re looking back out the entrance, before the last pillar gets cut out.

If you could see through that translucent plastic sheeting, you’d see the long hallway on the bottom level of Anderson Hall, which abuts Robinson.

All the hot/cold water for the Robinson Hall heating and cooling system comes in through the white pipes shown below. Unfortunately, they need to be raised up to let that metal duct at the right of the photo get in for ventilation. The complexity of the HVAC system in this building is astounding.

When you notice the AC going off in a few weeks, that’s why.

Below, the main area of the makerspace. “No X” means “Do not smash this column into rubble and carry it out in a wheelbarrow.”

Also could be used as a marker for where the eyewash will be installed, it turns out.

Below, the main area of the makerspace again. After 4 days of grinding, the floor is flat enough to top with new concrete and vinyl tile.

Below is what will be the Byrne Advanced Machining Area. This is where the heavy duty stuff goes.

And finally, a reverse angle of the BAMA.