How to make a drill press spindle lock clamp

Drill press spindle lock assembly

 

Drill press spindle lock assembly

 

It has been some time since my last post.  Summer is the time for swimming, sunshine, adventures, friends, fishing, and so on.  All of that has been keeping me pretty busy these days.  Here’s a post on a recent project to keep you entertained. I needed a spindle locking mechanism for my large drill press to help me convert it into a wood branding press.  The nice thing about having the  CNC milling machine I built for myself is that when I need a part or machine I can readily make it. It’s hard to imagine how I survived in the days before having CNC machining in the shop.

There was no built in spindle locking mechanism for my industrial drill press, and no add-on accessory available for purchase to lock the spindle.  I decided to take action and design my own add on mechanism.  I feel the best way to lock the spindle was to clamp the lower spindle were the Morse Taper socket is located on the bottom of the spindle (shown in the photo above).  I originally toyed with a removable pin mechanism in the spindle itself, or clamping the belts up top somehow.  Both of those ideas seemed more difficult then the solution I will share in this post.

   

I started with a piece of half inch aluminum stock.  This was an old adapter plate from some work years ago.  As such it had a few holes in it.  I carefully selected the origin of my part such that the machining would remove the material where the existing holes were located.  This careful setup up allows me to reuse scrap stock or old material from previous projects.   The next set of photos are just time lapse photos of the machining for your oogling pleasure, as such I will not comment much on them.

  

  

  

As you can see the finished part was milled out of the aluminum stock.  The only real downside to machining parts this way is at the end you are left with a small very sharp triangular nub on wherever the cutter started out.  I simply file this material off by hand.  For more exacting machining work, I would have made a jig by drilling and taping mounting bosses inside the part somewhere, this way the profile would be machined completely, resulting in a higher quality machined part.

The part took 30 minutes to machine. I might have been able to push up the machining speeds but I’m reluctant to push the speed as I do not want to break my end mill. This was my first part cut with the new HSMworks software I installed thanks to learning about the free version from Jim Wilkinson on Facebook a while back when he saw a previous project post.  Thanks Jim!

   

The next step after the CNC milling of the drill press spindle lock’s body was to drill and tap a single clamping screw. I used a 1/4″ – 20  tpi tap.  I tend to use quarter twenty bolts for just about everything not load critical in my designs as I stock a large variety of bolts in that size in my shop.  Simplifying your designs by using only a few standard threads for all of your projects is a good idea for hobby projects where weight is not a concern.

Above you see the more or less finished spindle lock assembly in place. I had to take the left side depth guage/stop assembly off, but as this is only a single nut it takes less then five minutes to put on the spindle clamp.  I cut the slot out in the wood shop on a miter saw with a thin kerf carbide tipped blade.  I could have milled it but it is very fast to use a saw blade for slitting operations.  The only thing missing from this picture is a spacer to clamp down on and lock everything tightly in place.

Above you see the finished spindle lock assembly.  I quickly turned down a bit of 1″ aluminum round and made a spacer of the right size.  She’s all clamped down and I am now ready to do some wood burning with our new electric branding iron.

I hope to be more active in posting both here on projectsbyzac.com  and photosbyzac.com in the fall.  August is chock full of good stuff and will likely keep me too busy for regular weekly posts.  But stay tuned in the fall, the 3D printer project will be finished before christmas (personal goal).  There will be lots of posts on that as well as continued upgrades on the CNC milling machine and the completion of the Cafe Racer Honda CX500 motorcycle.

 

Tips for hanging wall cabinets

Tips on hanging cabinets

Tips on hanging cabinets

My buddy Joe hit me up to help him hang some wall cabinets above his washer and dryer in the laundry room.   It’s always fun to hang out and be productive at the same time.    It was a much better way to spend a Friday afternoon then slaving away at the day job.

   

First steps is to measure the space and select a height.  There are rules for cabinet heights, but sometimes you don’t want to follow them.  Over the laundry was one of those times. It’s important to think about how you will use your cabinets and surrounding space before installing them.   We wanted to leave space to be able to put a laundry basket on top of the machine and still open the cabinets if needed.

how to install cabinets on the wall    installing cabinets using a temporary support rail

A good tip for installing wall cabinets it to put a couple of strips across the back into studs. You can easily shim and straighten the strips if the wall is wavy.  Then the cabinets attach easily to the straight, plumb, and level strips instead of struggling to shim each and every cabinet.  The strapping also allows you to have evenly spaced screws on the insides of the cabinets and also allows for additional screws versus screwing into the studs directly.  Sometimes strips are not feasible, in small kitchens/etc where the loss of 3/4″ space is critical. I did a kitchen on Beacon hill where every inch counted and we went into the studs directly. The down side is occasionally one cabinet only has two screws into a single stud to support it.   In this case, we used 2x4s to push the cabinets out a little bit.  The reach over the washer is difficult enough, so that extra 1.5″ out from the 2×4 goes a long way to make the cabinets more accessible.

Another useful tip is to put up a temporary rail to rest the cabinets on when installing them.  The right photo shows the first cabinet resting on the rail we screwed into the strapping we installed.   Cabinets are heavy, and usually a two man job.  With both of these tips you can hang cabinets without help if needed.  It’s always better to have a friend come help you, but it is possible to put up cabinets well solo using these two tricks.

tips for installing wall cabinets

After hanging both cabinets, we had to make a filler piece.   This meant a round trip to my workshop where we carefully cut the center filler board to the correct width.  When putting in the last filler on a cabinet installation like this I find it works best to put a small taper ~5 degrees or less on one side.  I cut the board ~1/16″ over the measured width of the gap between the two cabinets.  When we got back to my buddy Joe’s place we did final fitment by hand with a small hand plane and a jig I made years ago.  Sadly I did not think to take a pic of the jig setup.  The jig is simply a board with a stop screwed in perpendicular to another board.  It is put up against a wall on the floor.  It allows you to easily plane down thin strips of wood that are often needed when doing cabinetry installs.

Install tips for cabinets on the wall

The tapered edge we put on the final filler board allowed us to sneak up easily on a perfect fitment of the filler board. The last think you want is to have an ugly gap or seam in between cabinets due to poorly fitting this piece.  Of course We did a good job of it. The install is seamless, right against the walls on both side and we didn’t use any caulk or putty filler to  hide any gaps.  This is the way cabinets should be when installed, the right way.  All that’s left  was to add the doors.

Tips for hanging cabinets on the wall

With the doors put back on the cabinets, our job was done.  We celebrated with a cold drink while standing back and  admired our days work.   It was a great day, a fun project, and every thing went smoothly.

My low cost three axis CNC controller

three axis CNC controller build - insides

 

three axis CNC controller build - insides

I recently decided that it was high time to upgrade the original electronics I built for my CNC milling machine conversion on a RF7045 style milling machine.  The original electronics, shown below in the mess of wires and full size metal enclosure,  used a unipolar 4 axis control board and huge banks of power resistors to limit current.  It was poorly thought out and an ugly mess, but fully functional  The drawbacks to the original set up were primarily excessive heat generation (overheating in the summer) and an inefficient design.  Unipolar driven stepper motors produce considerably less torque then the same motor driven by a bipolar controller.   It was also a huge ugly mess with wires everywhere and heat sink banks outside the box.  The upgrade to the new CNC control unit was all spawned by Pololu’s black friday super sale on all of their great robotics and motor drivers.  If you haven’t been to Pololu’s website, definitely check out their products. Very good stuff at a good price, and on Black Friday 2011 a very very good price.

 

original unipolar four axis cnc controller hooked up to the RF 7045

The new low cost three axis CNC controller uses three Pololu A4988 stepper drivers in what I call the “Tie Fighter Configuration”.   I’ve  sandwiched them perpendicular to two larger circuit boards creating a channel for air flow.  With a   high velocity cooling fan and a custom heat sink mounted to Allegro’s A4988 microstepping bipolar stepper motor driver chip I hope to use these at or close to their 2.0 Amp max rating.  Eventually, when my reprap 3D printer is completed, I’ll print out a fan shroud to further increase airflow over the chips.  The data sheet for the A4988 is here,   pdf of the website for the pololu board is here,  current pinouts for board are here.  (data for me in the future)  As I continue to add or improve the CNC controller I will update this post.

million out the control panel for the ver 2.0 cnc controller  I/O board for the low Cost CNC controller

 The first version of my cnc controller had wires coming out of it connecting to the steppers.  This turned out to be terrible in use and was very unclean.   Version 2.0 had to have external mounted plugs for all of the external connections to the stepper motors, limit switches, power supply, and computer.  A bit of research on connector dimensions, a bit of CAD design, converting CAD to g-code (cnc machine program language) and the cnc machine running on the v1.0 cnc controller machined the next generation I/O board you see in the sequence of images above on the left.   In essence my CNC machine built parts to upgrade itself.  I think this is the coolest thing ever!  Having a machine that can make upgrades for itself.  Not quite self replicating like the Reprap 3D printer project but still pretty exciting stuff. As a kid this was the thing of Science fiction and not reality.

Connections to the milling machine and power supply labeled

The connections are labeled in the above photo showing the pre-testing assembled unit.  Post testing I realized I should add an on LED to the top as a main power indicator,  along with an LED indicator for the cooling fan power.  I ended up not being able to scrounge a usable DC/DC power supply chip.  I wanted to use a DC/Dc converter to  internally converting the 33V from the power supply into 12V for the cooling fan.  Instead I ended up using  a wall wort (aka plug in dc transformer) to supply power to the cooling fan and added an external plug jack to the case.   The bad part about this set up is there is no interlock.  In theory,  I could run the controller and not have the cooling fan powered up resulting in some sort of thermal meltdown.  The Ver 1.0 CNC controller had dozens of similar issues.  I had hoped to avoid this situation in this unit.   I plan to order a dc/dc converter  from Digikey in the near future and add the power for the cooling fan internally to prevent the possibility of thermal meltdown.

The above picture is of the “Tie Fighter Configuration” I’ve created.  The three little Pololu A4988’s are stacked in between the top and bottom boards.  This should create a nice cooling duct for the air supplied by the cooling fan to run over them to remove excess heat.  I will also make some copper u style heat sinks and mount them with Akasa double sided heat sink tape.  I’m hopeful that with this set up I can drive these little boards at close to their 2 amp max rating.  The CNC machine also made the aluminum bracket that mounts the boards to the right side of the case. More self upgrading on the machines part.  The Pololu’s are being run in their most basic configuration, ie. full step, with only step and direction imput from the computer to each board.   The three axis CNC controller also has a built in NC (normally closed) chain of limit switches and an E stop.  This set up uses a pull up resistor on the computer side.  When any one of the grounded NC switches is hit the output goes high and the computer instantly shuts off power to the motors sensing a mechanical limit or emergency.   Limit switches and an Emergency stop switch are necessities on any CNC controlled machine.  They keep  those G code programming errors from breaking something.  I’m using pc side controls, rather then the on board enable/disable built into the Pololu A4988 boards.

New three axis CNC controller in place and connected

 

Here she is, all hooked up and running the machine.  The Akasa heat sink tape has not arrived in the mail yet.  The CNC controller was run at only 0.7 amps for “testing” purposes.  Everything hooked up and worked well.  I was half expecting something to go up in smoke.   I am very pleased with the considerably smaller and less complicated version 2.0 CNC controller.  This new unit will drive the motors with about 40% more oomph which means faster machining time for me.    This is an ongoing project and I’m sure  I will continue to add and evolve in the coming months.  I’ll post more as I make changes.

 

Building an English Wheel Part 1

Many years ago I ordered hardened wheels so I could build myself a bench top English Wheel.  Since that time they’ve sat on the shelf in the garage waiting for motivation and need. For those of you that don’t know an English Wheel is a metal forming tool that allows you to gently stretch and form curves in sheet metal.  I’ve found ways around using one many times in the past.   The CX-500 Cafe Racer build is the straw that broke the camels back and has motivated me to finally build one for myself.  I often use a pneumatic plannishing hammer up until now to form compound curves into sheet metal.  However to make the fenders fit tightly to the wheels for the Cafe Racer I need an english wheel. With no way around it, I got to building.

I used whatever I had on hand for the C frame.  In this case, 2×4 and 2×3 tubing.  I’ll reinforce the structure beyond this quite a bit with 45 degree corner gussets and possibly full lengths of 2″ x 1/4″ angle iron.  At this point the frame is just tacked together to make sure that it all fits and works.  The bracing and reinforcing will be done after I’ve finished with the mechanisms.  It is important to make sure everything fits and is aligned correctly before you weld up all the joints.   It is a lot easier to cut a few solid spot welds then to cut fully welded seams when you realize something’s off a bit in the end.

 

   

The upper wheel is very heavy. Not a surprise at 6″ in diameter, 3″ wide and solid alloy steel.  The upper mount is fabricated from some 2″ x 1/4″ angle iron.  The pin I turned from some 1″ rod I found in the stock rack.  It’s been there for ages from the amount of dust on it.  I”m not sure what it is, but I needed Carbide tooling to turn it and bi-metal hack saw blades weren’t hard enough to cut it.  Whatever alloy it is certainly something hard and strong.  Hopefully suitable for the 3/4″ pin that the wheels will rotate on.  If it bends I’ll just make another set of pins from something stronger like 4140.

More on this project soon as I hope to finish it in the coming week