Digital Readout for the Mill

George CarlsonTools

The Digital Readout system has been installed and the mill is ready for action.

The Digital Readout system has been installed and the mill is ready for action.

In my opinion, no milling machine should be without a digital readout (DRO).  If you ever had to use an old machine without a DRO, you would be amazed that anyone could produce good results.  Counting turns of the handle, reading tiny numbers on dials, making sure all movements were from the same direction, and having to compensate for lead-screw wear; none of this is necessary if the machine has a DRO.

There several different technologies used to build the linear scale used to determine machine position.  The DRO on our mill uses high precision glass scales.  Inside the scale housing (spar) is a long strip of glass.  The glass was coated with a fine layer of chromium, then fine lines were etched in the chrome as many as 50 per mm. The reader module, which is attached to the spar, slides along the glass scale.  The circuitry inside the reader module shines light through the glass scale and using a pair of light sensitive detectors can “read” the glass scale and output pulses to the display unit.  The display unit counts the pulses to determine location.  The small computer within the display unit can provide many different ways to use the position data. These functions are beyond the scope of this blog.

The machine should be ready for installing in The MakerBarn sometime this next week.  Look for upcoming classes in machine operation and certification.


The Stand is Completed

George CarlsonNews, Tools

Sieg SX3 on stand

The stand is finished, well, until we decide to make some improvements.  The stand has small iron casters to make it easy to move, but also has leveling screws to level and lock the machine in place.

Now we await the arrival of the digital readout (DRO) system.  This consists of a display units and three glass scales.  The linear glass scales are packaged in aluminum spars that protect the scale and keep it free from dust and dirt..  The readout device has a resolution of 0.005mm, which is about 0.0002″!

Milling Machine for the shop

George CarlsonNews, Tools

A new addition for the shop.  This small milling machine uses the same type of tooling as a Bridgeport style mill.  So it should work well for use until we can get the larger machine.  I will be building a stand and installing a Digital Readout, so it will be a couple of weeks before we can move it to the barn.  With this machine we will be able to machine plastics, wood, and almost any metal, including steel.  Each member who wishes to use the machine will have to supply their own cutting tools.  This would typically be a set of end-mills, which is not too expensive.  When learning to use the machine, it is not uncommon to break or otherwise ruin cutting tools, so it’s best if each person is responsible for their own.  I’ll make some sort presentations at upcoming meetings about operating the machine tools, so stay tuned.

Sieg Super X3

Sieg Super X3 Vertical Milling Machine

Why do you want to be a maker?

George CarlsonMaking

Alpha Geek2

My father was a cabinet maker and the son of an immigrant farmer, so I guess that’s where it came from.  Why would anyone want to build it, when you could just go out and buy it?  There’s something about the feeling that this object, what ever it is, was made by my hand.  I guess this is part of the human psyche.  Without this basic human need there would be no scientists, engineers, artists, or philosophers.  On some people, this need is just a bit more intense than others, so here we are.

In this day and time, the support of making is needed more than ever.  We, and our kids, are bombarded with commercialism.  Kids need to be taught and shown that each and every thing they see online or in stores was made by someone.  Guy Lautard  wrote a series of books called “The Machinist Bedside Reader”.  The books are a collection of anecdotes and how-tos related to metal working.  In one of the stories he tells about a delivery man who is picking up a package at a machine shop.  He asked the machinist, “What do you make here?”  The machinist replied, “Gears”.  The delivery man looked amazed and said, “I didn’t think you made gears, I though you just bought them”.

So get out in the shop, or your makerspace, and make something.  Even if it’s just a pile of chips.

There’s good stuff in old junk

George CarlsonBuild Log, Making, Materials

Overhead projectors are not used in schools anymore.  So you can usually get them for just a few bucks at the online school auctions.

If the projector works, it can be a good way to enlarge objects and trace them on pieces of plywood.  But they’re even more fun to disassemble and scavenge parts for future projects.  My grandson and I took two projectors apart this afternoon (we have more).

One of the best finds is the fresnel lens located just below the glass platen.  These lenses are about 12″ square and have a focal length of just a few inches.  Just what you need for solar energy projects.  Be careful, it’s easy to start fires with these.

Fresnel lenses from the projector can be a lot of fun

Fresnel lenses from the projector can be a lot of fun

Other parts such as power cords, power switches, limit switches, super bright lamp holders, fans, metal pieces, and optics can be found.  The projection head almost always contains a high quality first-surface mirror.

They usually come up in auction in groups of a half-dozen or more.  So if you’re not careful, you can end up with a garage full.  Check auctions at and


CNC Class Already Filled

George CarlsonEvents, News, Tools

It didn’t take long.  By the time I got this blog posting organized, the class was already filled.  Never fear, there will be additional classes in the near future.

The class will be concentrating of getting members certified to use the two CNC routers we have.

The small router, “Mini-Chop” was primarily designed for mechanical etching of circuit boards.  Its super precise control of the Z axis also makes it great for engraving Romark type plastic.  This is the material with a thin top layer of plastic over a thicker base of a different color.

The Mini-Chop, designed for circuit board making.

The Mini-Chop, designed for circuit board making.

We also have “Robo-Chop”, designed and built by member George Carlson.  This machine has a 26×48″ build space and a 3HP water cooled spindle.  It is on loan until we can purchase our own high-end CNC router.

Just finished cutting the big gear for Makey.

Just finished cutting the big gear for Makey.

Both routers use the Mach3 control system, so operation is pretty much the same for both machines.

The course will be taught in three sessions.  Session one is an introduction to CNC routers, operation and tooling.  The second session is all about V-Carve, the software used to design objects and create tool-paths.  In the last session we will cut the homework assigned in session 2.  Everyone will get a chance to show-off what they can make with an 8×10″ piece of MDF.

Emails will be sent out as soon as the next class is scheduled.


2016 Houston Mini-Makerfaire

George CarlsonEvents, Making, News

Imagine the Possibilities, our theme for the Makerfair

It was crazy!  The Mini-Makerfaire was held at the George R. Brown convention center on November 12 and 13. We had a 20′ x 20′ booth with lots of small projects for the kids to work on.  To select the project, the person would operate the large switch on the MakerBarn Robot Control Panel.  A large version of Makey would spin his “Wheel of Making” and randomly select a number for the project.

Jeanie and Greg are setting up the booth

Jeanie and Greg are setting up the booth

We had around 200 – 300 kids (and some adults) build the projects Greg created.  The booth was very crowded both Saturday and Sunday.

It was busy at The MakerBarn booth!

It was busy at The MakerBarn booth!

With all the clattering from Makey, and the constant use of the Aztec drum, we had to be the noisiest booth at the show.  Another big attraction was the Van de Graff Generator.  After a transfer belt change on Sunday morning, the generator was producing 10″ sparks.

Ouch! That thing is mean.

Ouch! That thing is mean.

Apologies to some of the other booths that may have had some interference from the Van de Graff.  It seemed to be upsetting a few computers in the area.

The stereo microscopes are always popular

The stereo microscopes are always popular.

People were amazed at what could be done with a laser cutter.

People were amazed at what could be done with a laser cutter.

Buttons, Spinners, Reindeer, Jack Knives, and Penny Tops were made by the dozens.  Thanks to all that made the booth such a success.


Our new Powermatic Tablesaw

George CarlsonNews, Tools

This is a Powermatic 66 built in the early seventies.  It was in very good condition, considering the age, when we got it.  The purpose of this saw will be to cut dados and box joints.  This can be done on the SawStop, but the brake cartridge needs be be changed if a dado blade is installed.  This will save our woodworkers alot of time when switching between normal and dado cuts.

PM66 Moving The saw is pretty heavy, just ask Greg.  Once we got it in the shop, it was cleaned and the bearings and belts were replaced.

cleaned up 66Here’s the machine all cleaned up.  The machine has a 3HP three-phase motor.  Since we don’t have three-phase power at the barn, I installed a VFD (variable frequency drive) to provide the three-phase power.  One advantage of using the VFD is that it allows the start and stop time of the motor to be set.  So you can make it start very smoothly and stop quickly, but not so fast as to loosen the saw blade.  Since this saw will be dedicated to the use of a heavy dado blade, the stopping is a concern.

PM66 doneNow with brand new fence, extension table, and electrics the saw is ready for many years of service.

More Additions to the Shop

George CarlsonBuild Log, News, Tools

It’s been busy lately. John Buckley and I built a high-tech router table. The machine uses a 3HP water cooled router spindle and an Arduino controlled router lift. The computerized lift makes making precision cuts easy.

The MakerBarn Router Table

We are also in the process of rebuilding a Powermatic 66 table saw. This a heavy-duty industrial saw that will be configured for making dado (wide slot cuts) cuts and box joints. This means we can make dado cuts without having to re-configure a saw. A wonderful time saver.

RoboChop CNC Router

RoboChop CNC Router

Lastly, the RoboChop has arrived! The RoboDhop is a 27×48″ High Precision CNC router. It has a 3HP water cooled spindle and high precision ball screws for positioning. It is on-loan as a way to see if we would like to purchase our own CNC Router. Shortly I’ll announce classes to teach Vectric V-Carve software and how to use the machine.

A new addition to the shop

George CarlsonNews, Tools

Abrasive Blasting Caninet

Abrasive Blasting Cabinet

One of the latest additions to our arsenal of tools at The MakerBarn is an abrasive blasting cabinet. Since we have a large air compressor and the entire building has been plumbed for compressed air, installation of the unit was easy.
“Sand blasting” can be quite messy, but with the sealed cabinet, the operation is quite clean and comfortable. Parts to be blasted are brought in through a door that seals. The operator’s hands go into large gloves in the front of the cabinet and a window allows the operator to see inside. A shop vac keeps the air inside the cabinet clear of dust.
The unit has been supplied with 100 grit snow-white Aluminum Oxide abrasive. This is a fine abrasive that looks much like sugar. It works well for quickly removing rust and paint from metal surfaces. It also works well for texturizing a surface, or etching glass or plastic. The vinyl cutter can be used to produce a mask for etching glass. The fine abrasive cuts glass, but does not destroy the vinyl.
When using the blaster, make sure your part is clean and free of grease, oil, of loose paint chips. Grease and oil can contaminate the abrasive and make is useless for etching projects. Large paint chips can clog the blasting gun.
The gun should be held at an angle to the surface, not straight on. The idea is to scrub the surface. Blasting directing down unto the surface can peen the surface and damage the part.
Bring in an old rusty yard tool and try the blaster on it. You’ll be pleased with the results.