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David Burrell

KR33CNCv2 diy cnc machine

How do you connect a brake to a ClearPath DC servo – Neo7CNC

By | CNC, DIY, How-To | No Comments

I’ve been asked this question many times since I started using the ClearPath DC servo motors from Teknic. First, lets review the WHY you’d need to use one. Unlike standard stepper motors, most servos do not present any resistance to rotation when the aren’t powered or enabled. Meaning that if the servo motor encounters a fault condition or loses power, it can freely spin. On the X and Y axis of most vertical CNC machines this may not be an issue.  However, on the Z axis, you have all the weight of the spindle motor and brackets pulling down on it.  Gravity will take over if there is a fault or lose of power.  This could be catastrophic for the spindle, endmill, work piece or even the CNC machine itself.

To safeguard against the Z accidentally dropping, we can use an electro-mechanical brake between the shaft of the servo and the shaft of the ballscrew that moves the Z axis up and down. For this example, I’m using a brake from Inertia dynamics that I found on eBay.  It operates on 24vdc and when at rest (unpowered), it’s locked.  If you supply it with 24vdc it unlocks and it can rotate.

The overall setup is straightforward. The ClearPath servo has all the control we need already built in.  There is an output from the servo that is “ON” when the servo is powered AND enabled.  We’ll use this logic combined with a Crydon solid state relay to control the brake.  Wiring is also pretty simple.  We’ll also need power supplies to power the relay, brake and servo (servo power supply not pictured).  The Allen-Bradley 24vdc power supply is for the Inertia Dynamics brake and the 5vdc Mean-Well power supply is for the solid state relay. The relay will control power to the brake and the relay will be controlled by the output from the ClearPath servo. Pay close attention to the polarity on the solid state relay as it is polarity sensitive on the input and output unlike standard mechanical relays.

ClearPath DC servo motor: CPM-SDSK-2311S-EQN

Inertia Dynamics brake: 8923-2331 – purchased from eBay.

Solid state relay: Crydom DC60S3

Gene Haas Center

The Gene Haas Center for Manufacturing Innovation in Greenville SC.

By | 3D Printing, CNC, Software | No Comments

I had an opportunity to visit the Gene Haas Center for Manufacturing Innovation last week.  I loved it! I was like a kid in a candy store. This brand new center has areas for CNC (subtractive manufacturing), manual milling, lathe work and grinding, 3d printing (additive manufacturing), pneumatics, hydraulics, robots, mechatronics and more! I was there for a lunch and learn that featured 3d printing technology from HP and MarkForged and also 3D design software from Solidworks. This facility is used by Greenville Technical college, Clemson University and also by local industry.  They are also starting an business incubator very soon.  Watch the video below for more information.

Neo7CNC - Chop Saw Clamp with Valve

DIY Pneumatic Saw Clamp – Neo7CNC

By | DIY, Non-CNC, Start to Finish | No Comments

DIY Pneumatic Saw Clamp

I made one of theses many years ago when I was helping my father with a shop he was building.  We were using very long 2×4’s and this style pneumatic clamp helped hold the extra long boards while we cut them down to a more manageable size.  It can also save a finger or two by keeping your hands aware from the blade in the event that things go sideways 😐

 

What you’ll need:

Your saw or other application may vary, so these parts are just examples based on what I’m showing in the video. The pneumatic components directly below are from AutomationDirect.com 

  1. AVS-53D2-HL 5 port 2 position toggle valve 1/4 NPT (Qty 1)
  2. A17020SN 1 and 1/16 bore 2 inch stroke 1/8 FNPT spring return air cylinder (Qty 1)
  3. SBC-14N Bronze cone silencer 1/4 MNTP (Qty 2)
  4. MS14-14N Male straight 1/4 tub to 1/4 MNPT (Qty 3)
  5. BFRHP-14N recessed hex head plug 1/4 MNPT (Qty 1)
  6. PU14BLK100 Black poly urethane 1/4 OD tubing 100ft (varries)
  7. ME14-18N 1/4 tubing to 1/8 MNPT (Qty 1) OR if you want to control the flow of air into the pneumatic cylinder so it doesn’t move so abruptly then use FVR14-18N flow control valve meter IN for 1/4 tubing to 1/8 MNPT (Qty 1)

Along with the pneumatic items above, you’ll also need:

Some material to mount the pneumatic cylinder.  I used 3/16 (4.76mm) thick x 1.5 inch (38.1mm) wide flat steel bar.  The piece that connected the 5/8 bolt (15.875mm) to the pneumatic cylinder is 6.5 inches (165.1mm) long.  The “spring” top piece is 4 inches (101.6mm) long.  The 5/8 bolt was 10 inches long and it fit the clamp hole on the saw perfectly.  I used 2 5/8 nuts to sandwich the 2 pieces of flat bar.  I didn’t have a large enough drill bit to drill the 5/8 hole and cylinder hole properly. I ended up using an old step drill bit that was large enough to get us there.  It wasn’t pretty, but it got the job done. The last thing you’ll need is something to mount on the end of the pneumatic cylinder so you don’t damage your work piece when you clamp it.  I used a small section of UHMW rod.  You can find small lengths at McMaster-Carr (1 inch (25mm) rod a foot long for @ $3 at the time of this post) or you can use a rubber stopper or wood. You’ll also need to use one of the MS14-14N connectors and either plumb it to your air supply or mate it with a quick air hose disconnect.

X-Carve CNC Machine Inventables

X-Carve DIY CNC Machine from Inventables

By | CNC, DIY | No Comments

Here’s a recent video series where I talk about the X-Carve CNC machine from Inventables. I also have some pictures of the assembled unit as well as a few shots of their newly released X-Controller.

I think the X-Carve is good for beginners and people looking to make crafts.  With the spindle upgraded to the DeWalt 611 you can cut much faster and use larger bits.  This comes at the price of increased noise from the router.  I’ve seen others build an enclosure to keep the dust and sound at bay.

For the price, it’s a decent introduction to CNC. Especially when considering the larger of the two with around a 40″ x 40″ work envelope.  With the drive mechanisms being belt oriented, be prepared to tighten them occasionally.

I found the control software very easy to use.  Its a very pleasurable experience in fact.  The first job on the Shapeoko 2 (version prior to the X-Carve) used the same Easel software and it was so straightforward that my 9 year old son ran it.

I beta tested the X-Controller and was also very pleased with the ease of setup and use.  As I said in the video, the last thing I want to do after I finish building the X-Carve is building the electronics.  The X-Controller solves that.  It’s very plug and play and well thought out though I’d like to see some dust control and an external e-stop option on it.

Click HERE for the picture gallery.

Neo7CNC DIY Parts Tumbler

DIY Parts Tumbler

By | CNC, DIY | No Comments

When I was researching how to finish the LoopAliens, I decided to build a tumbler.  It turned out well after I converted it to a larger, more capable motor.  It’s ended up being more of a ball mill than a tumbler, but it did work.  Creating it gave me a good excuse to turn out some really nice parts on the larger CNC machine I built some years ago.  Click HERE to see the CNC machine I used.

After the proof of concept, I ended up buying a very large vibratory tumbler to run production parts with.  It allowed me to finish hundreds of parts at a time rather than 50.  Creating the “ball mill” was a good educational experience.

Here are some decent pictures from the DIY parts tumbler build I did some time ago

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