Search found 226 matches

by veng1
Fri Sep 04, 2015 2:32 am
Forum: Discussion
Topic: Shapeoko 3 - Expansion Packs
Replies: 165
Views: 34841

Re: Shapeoko 3 - Expansion Packs

One of the things I've found in trying to use the structural elements that are "L" shaped is that they don't, at least by themselves, resist twisting. Extrusions may cost more but also may end up worth the extra cost. A box section just works better for me. What little I know about structures was mo...
by veng1
Thu Sep 03, 2015 8:18 pm
Forum: tinyG
Topic: Using TinyG for SO2/ 3D Printer combo
Replies: 7
Views: 2559

Re: Using TinyG for SO2/ 3D Printer combo

@cvoinescu: Agreed. An external temp controller is a hack. I admitted that I didn't have an elegant solution, at least not yet. A splitter, two USB cables and a second board to control just the extruder with a synchronization method might work although it still requires two boards (and software hack...
by veng1
Thu Sep 03, 2015 2:20 pm
Forum: tinyG
Topic: Using TinyG for SO2/ 3D Printer combo
Replies: 7
Views: 2559

Re: Using TinyG for SO2/ 3D Printer combo

The motion on a 3D printer needs to be coordinated but the heater doesn't really. All that is needed is a binary signal that confirms set point has been reached. There are many PID controllers that would do that along with a fairly minor hack to some 3D printer software like Marlin to just control t...
by veng1
Thu Sep 03, 2015 1:59 pm
Forum: Discussion
Topic: Shapeoko 3 - Expansion Packs
Replies: 165
Views: 34841

Re: Shapeoko 3 - Expansion Packs

Most of what I cut is about an inch or two into a box that is 12 inches tall (~300mm). My solution with the SO2 was to build a cart out of relatively large extrusion and then bolt the SO2 to the top. I then built a semi-permanent fixture to hold the part that I want to cut below the normal work surf...
by veng1
Tue Sep 01, 2015 3:39 pm
Forum: Discussion
Topic: Zeroing X Y with a camera
Replies: 3
Views: 1174

Zeroing X Y with a camera

There is an interesting topic on the Carbide 3D forums that I thought I'd point out here. Of course, Will has already found it. http://community.carbide3d.com/t/new-zero-camera/485 After a good bit of discussion, it links to the following: http://beatty-robotics.com/zeroing-a-cnc/ Beatty Robotics us...
by veng1
Fri Aug 28, 2015 4:41 pm
Forum: Electronics
Topic: S3 stops mid-job
Replies: 190
Views: 28651

Re: S3 stops mid-job

Your testing could go faster if you add a bigger garage with multiple door openers.

Better yet, a multi car drive through garage with door openers at both ends.
by veng1
Fri Aug 28, 2015 2:20 am
Forum: Electronics
Topic: S3 stops mid-job
Replies: 190
Views: 28651

Re: S3 stops mid-job

I agree there can be a problem with terminology. I use the convention that the "earth ground" is also the "safety ground". In the States, it is the round pin on the 3 pin outlet, connected typically by a green wire. By regulation, it is only allowed to connect to AC neutral for each circuit at the f...
by veng1
Thu Aug 27, 2015 11:58 pm
Forum: GRBL
Topic: GRBL for H-Bridge Mod
Replies: 10
Views: 2407

Re: GRBL for H-Bridge Mod

I'm not sure how you actually implement an H-bridge with a ULN2003 as it only sinks.

To get reasonable holding torque, I think you need a current source also.

Running steppers cold is like a ship in a harbor, it may seem safer but that is not what ships are intended for.
by veng1
Thu Aug 27, 2015 11:51 pm
Forum: Electronics
Topic: S3 stops mid-job
Replies: 190
Views: 28651

Re: S3 stops mid-job

Have you actually measured that? Most supplies I'm familiar with do not tie the negative side of the power to earth ground but I agree if it is so, it may be a major part of the problem. Even the ones I've seen typically have to do it with a removable jumper. I guess I need to measure mine also alth...
by veng1
Thu Aug 27, 2015 10:18 pm
Forum: Electronics
Topic: S3 stops mid-job
Replies: 190
Views: 28651

Re: S3 stops mid-job

There can be some safety concerns about grounding logic voltages to equipment ground. Adafruit and others make a USB isolator: https://www.adafruit.com/products/2107 This uses an Analog Devices part similar to one I've used successfully in the past to connect a tablet to a machine with a large compr...