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Guys tell me where I am going wrong.
A Lasers cutter would be perfect tool for reprap as it does not create any vibration. Unfortunately they are expensive and probably not a good tool for
a hobbyist due to cost and the ability to blind yourself.
However a Laser is nothing special. It simply delivers an intense beam of parallel light to a small spot which gets very hot and then vaporises the ma
by
stephen george
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General
Hypoon () said
I really like the idea of a stable/development setup.
Triffid_hunter said()
Hypoon, that's a long way down the track- just look at desktop linux.
My reply
Actually the idea of a Stable version and a development version was taken from the linux kernel where you used to have a stable version which was even version number and an odd version which was developments.
In my case I wa
by
stephen george
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Administration, Announcements, Policy
HI Triffid_Hunter ()
I will be very interested to see this code when it is finished.
Good luck and happy debuging.
Stephen
P.s. Glad you are writing it in C without floats. Smart move.
by
stephen george
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Firmware - experimental, borrowed, and future
Reply to the original post.
I hear your pain I really do. I bought a kit almost two years ago and it's been a baptism of fire ever since.
You are right about the documentation. I feel we need two versions of the documentation.
A stable version for beginners and an experimental version for the more advanced.
I shudder to think how many people have been turned away due to the confusion of tryin
by
stephen george
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Administration, Announcements, Policy
Triffid_Hunter () Said
I think the reason that the controller is calculating curves and things is that the step timing is as critical
as the movement speed, and the extruder has to extrude at a rate proportional to movement speed to within a
relatively tight tolerance. PCs without a RTOS are dreadful at tight timing, and the (usb) serial link coupled
to another (async/rs232) serial link doesn
by
stephen george
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STEP-NC
Thanks SebastienBailard () for createing a new area for the Step work.
by
stephen george
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STEP-NC
Very nice pictures
Thanks for showing them.
Stephen
by
stephen george
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General
kintel () said
> I don't quite see where STEP fits into this picture though, except as a new file format front-end to Skeinforge.
Let me explain
1) Direct replacement for G code. (Output of skeinforge)
2) International standard
3) Use xml
4) Paradigm shift
i.e. Describes the shape and then uses a database to lookup and calculate the tool path as defined by your system.
5) Industry Standard
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stephen george
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STEP-NC
BodgeIt () said
The only problem I see is the huge amount of Com's overhead involved when printing at the moment there is no hand shaking or Error checking in this Com's link.
My response
I had that exact same thought. So I added a CRC byte to each command and opted for a binary comunication scheme rather than ASCII. Then I discovered that with a loop command and a little flow control the amoun
by
stephen george
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STEP-NC
Hi Triffid_Hunter ()
you said
I haven't looked at the darwin design for a while,
but how easy would it be to remove some of the constraints on the z-axis?
My reply
I had untold trouble with the Z-axis. In the end I opted for a rebuild
using only three Lead screws instead of four. which reduced the friction by 25%.
Also I found that having two nuts on each thread (bit from bytes design)
incr
by
stephen george
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Mechanics
BeagleFury () said
That seems much too low level to me. If this is the level that you want to work with, I'd suggest writing a program that can generate C or assembly for the firmware, and a boot-loader, and execute it that way. Alternatively, implement an interpreter/compiler on the firmware itself.
My reply
Yes the firmware would be written in C. The idea is for the PC to convert from a high l
by
stephen george
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STEP-NC
liav () said
> Even after removing the anti-backlash springs, loosening the nuts which hold the bed to the z-posts, very very liberally soaking the entire system with engine oil and loosening the belt, my z axis still has a tendency to bind and stop moving.
my reply
I feel your pain. Mainly because I had the same problem.
I was building a darwin/bit from bytes v2 and I found that the grub sc
by
stephen george
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Mechanics
Apologies for the late reply.
Thanks Beaglefury () for your post I have spent much time considering it.
Beaglefury () said
What do you forsee as the minimum set of commands for the embedded software. How does that differ from current G code implementation? Did you just plan on removing the linear and temp unit specific conversions only, and retain the remaining commands?
My response:
I want
by
stephen george
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STEP-NC
Thanks SebastienBailard () for the level of support. Much appreciated.
Before we get started is there anyone out there who sees a problem with what I have proposed?
A sanity check would be greatly appreciated.
regards
Stephen
by
stephen george
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STEP-NC
Beaglefury () said
Glancing at STEP-NC, it appears it targets subtractive manufacturing.. Am I missing something here?
If this is the case, I think STEP-NC may not fit well into a reprap tool suite, since there is no need to "drill and rough in a pocket", or to "plan a path for a cutting tool that avoids current features". Many of these subtractive problems do not exist for additive processes.
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stephen george
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STEP-NC
BodgeIt said
Take a look a the processor required in the average ink jet printer it is very much on a par with the processor we are currently using. Now look at the processors in Laser printers or the processors used in graphics cards. Gone are the days of the simple dumb peripheral device tasks need to be delegated down to the firmware. Thus saving system bandwidth and processing power.
My re
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stephen george
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STEP-NC
BeagleFury ()
This seems very much to be the kind of thing you are proposing, are you not?
My reponse
yes
Note: The implementation is of STEP called step-NC is open souce. Boeing want CNC systems to use it as it means that parts are exactly as requested. rather than having been interpreted by a machinist and then using g-code.
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stephen george
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STEP-NC
Triffid_Hunter () said
I think the reason that the controller is calculating curves and things is that the step timing is as critical as the movement speed, and the extruder has to extrude at a rate proportional to movement speed to within a relatively tight tolerance. PCs without a RTOS are dreadful at tight timing, and the (usb) serial link coupled to another (async/rs232) serial link doesn't h
by
stephen george
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STEP-NC
My bespoke G-code will probably not work with your reprap and create the same shape.
As a result each object is not guaranteed to be the same.
This costs companies like Boeing millions a year.
The idea is to build a descriptive language which will provide the same part now and
10 years down the line with a different CNC machine when you need another replacement part.
To build an object the pro
by
stephen george
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STEP-NC
I don't know about you but I prefer a real book.
Especially if it is laid out in a linear fasion and is well researched.
I can see two types of books being popular.
1) Reference book.
2) How to book (starters manual with background)
Stephen
by
stephen george
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Administration, Announcements, Policy
spacexula () said
> I don't think a printed book would be appropriate for the 3d printing community at this time. Too many things in flux, and given a 6 month lead time on a printed book, from purchase to publication,
www.lulu.com allows you to publish a book instantly. The book can be updated and used to fund the reprap.org project. (It also supports "soft" books to)
Stephen
by
stephen george
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Administration, Announcements, Policy
It's good to see people doing well with MDF.
I have a fully working Darwin. However fed up with glueing acrylic back together after tightening a bolt too much. I am rebuilding the whole thing with 16MM MDF and stealing the important / reliable parts.
So far reprap 2 (the revenge) is going smoothly.
Stephen
by
stephen george
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Mechanics
Look at
Attachments: GCode_Interpreter_v17.zip (25.7 K
On reply Date: December 18, 2009 01:06AM
regards
Stephen
by
stephen george
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RepRap Host
Hi Adam.m.Nelson
How did it go?
Stephen
by
stephen george
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RepRap Host
Drummerboyx
I am sure you have my updated version of the firmware.
Anyway if you look in tested section of Gcode_interpreter.pde you will find
// Reprap Newest software (global.FiveD=false,extruder0.extruder speed 255)
Try setting the extrude speed to 210 on the extruder0 screen.
regards
Stephen
by
stephen george
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RepRap Host
p.s You probably want to comment out #define DEBUG_M101_why_have_you_stopped
I was using it to debug why the extruder kept stopping on every layer.
Turns out it was a code fault in the original firmware.
You also will need to switch global.FiveD=false in the reprap host software
Give us a shout if you have any problems.
regards
Stephen
by
stephen george
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RepRap Host
As promised here is my latest code.
I have got it set to switch off the stepper motors when not in use and the temperature of the extruder is defaulted to 200c so it is ready to use when my PC has booted.
You probably want to go through the parameters.h to enable or disable any code.
Good luck
Stephen
P.s. All disclaimers. Code given as is with no warranty.
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stephen george
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RepRap Host
Extruder speed is an M command.
It is supplied by the reprap host / skeinforge software.
To add confussuin we have two sets of units
PWM and MM/minute. You will be PWM which has a range of 0-255.
(3000MM/Minute which is the reprap host software default may get converted to 255)
// Set speed of extruder
M108 S100;
// set temperature guard
M124 S020;
// start motor
M101;
regards
Stephen
by
stephen george
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RepRap Host
Hi Fred
> Dang a six dollar chip on a board with replaceable chip, verse hours to try and shoehorn code growth into a tight area, seems to be a win/win solution if you can double the flash and ram.
I suppose it depends if you are one of the billion people on earth who earn less than $2 USD per day or someone from a first world country.
$6USD would represent 3 days work.
The firmware in que
by
stephen george
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RepRap Host
I have a fully functional reprap using much less than 16kb.
The loss is that you can't use accelerated 5D Gcodes with the firmware
straight out of the box. (as it were).
regards
Stephen.
P.s. Happy to share my modified firmware if you are intersted. Its the offical version with a few bugs removed.
P.s. Gen 4 electronics is due out next Feb I believe.Might be an idea to wait before buying Gen
by
stephen george
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RepRap Host