Please help me finish my Longboat Prusa

Hi,

Sorry to just leap in here with this, I have done some searching but am not finding anything.

I have a Longboat Prusa Kit from thereprapkitstore which arrived yesterday and is now largely assembled to the end of the instructions in the wiki here:-
[www.reprap.org]

So my questions are:-

1. Can anyone reassure me on this link/bridge on the Sanguinololu board? Electronics really aren't my area and I am nervous about doing this. Is it definitely correct? Just link with a swipe of solder?(it is a 1.3a board that is pre-assembled) [www.reprap.org]

2. The kit shipped without a thermistor or the Kapton tape, which will be shipping separately later, but I dont really want to wait for them. The thermistor isnt specified, is somewhere like Maplin likely to have a suitable one?

3. Wiring?!?!?:-
i. I can understand the mounting of the micro-switches for end stops but not the pins to use and to connect to the board, this presumably needs to be correct...
ii. The heated bed has a mosfet on it and so I have three connectors on my bed, again presumably these need to be wired correctly but I have no wiring diagram or whatever.
iii. Hot end heater resistor resumably just connects across 2 of the pins on PWR1 TIP... but which two?
iv. Thermistor presumably connects across e-therm (extruder thermistor)?

4. Should I get another thermistor for the bed to go across B-Therm (Bed thermistor?)


Sorry to have so many probably easy questions, I am sure these things must be covered somewhere but I am struggling to find clear answers. Any help much appreciated.

George

If you want to get on skype with a web camera, I might be able to help guide you. PM me if you like, and I'll send you my skype info.


-Wildseyed-

gsport Wrote:
-------------------------------------------------------
> Hi,
>
> Sorry to just leap in here with this, I have done
> some searching but am not finding anything.
>
> I have a Longboat Prusa Kit from thereprapkitstore
> which arrived yesterday and is now largely
> assembled to the end of the instructions in the
> wiki here:-
> [www.reprap.org]
> embly
>
> So my questions are:-
>
> 1. Can anyone reassure me on this link/bridge on
> the Sanguinololu board? Electronics really aren't
> my area and I am nervous about doing this. Is it
> definitely correct? Just link with a swipe of
> solder?(it is a 1.3a board that is pre-assembled)
> [www.reprap.org]
> olu_board_modifications

Actually I can't see how that works properly unless you also remove the MOSFET. It links gate to drain. If the MOSFET was still fitted it would clamp the drive signal to its own gate threshold, which could be less than the gate threshold of the external MOSFET it is driving.


>
> 2. The kit shipped without a thermistor or the
> Kapton tape, which will be shipping separately
> later, but I dont really want to wait for them.
> The thermistor isnt specified, is somewhere like
> Maplin likely to have a suitable one?

No I don't think so because you need a 100K one rated for 300C. RS and Farnell sell them, see the Reprap thermistor page [reprap.org]

>
> 3. Wiring?!?!?:-
> i. I can understand the mounting of the
> micro-switches for end stops but not the pins to
> use and to connect to the board, this presumably
> needs to be correct...

Usually the outer two pins and ignore the middle which gives a normally closed connection.


> ii. The heated bed has a mosfet on it and so I
> have three connectors on my bed, again presumably
> these need to be wired correctly but I have no
> wiring diagram or whatever.

There is a diagram here that Adrian uses, I presume it is the same: [reprap.org]


> iii. Hot end heater resistor resumably just
> connects across 2 of the pins on PWR1 TIP... but
> which two?

The four pins are connected together in two pairs see: //reprap.org/wiki/Fileanguinololu12.svg


> iv. Thermistor presumably connects across e-therm
> (extruder thermistor)?

Yes
>
> 4. Should I get another thermistor for the bed to
> go across B-Therm (Bed thermistor?)

That would be a good idea.

>
>
> Sorry to have so many probably easy questions, I
> am sure these things must be covered somewhere but
> I am struggling to find clear answers. Any help
> much appreciated.
>
> George

I am not familiar with the kit, these are my best guesses.

Edited 2 time(s). Last edit at 02/08/2012 08:57PM by nophead.

---

[www.hydraraptor.blogspot.com]

Some info in thread below, I abandoned the bed mosfet idea and am driving the resistors from the main board (no link).

forum topic

Thanks for the responses on here, sorry to have not come back sooner, almost as soon as I posted this I caught Pneumonia and was out of it for a couple of weeks then trying to catch up with work.

I have abandoned using the extra mosfet on the heated bed and modifying the board in favour or just letting the board drive the resistors (which I have in parallel)

But I am still a bit confused on a few wiring jobs.


1. I need to wire the end stops normally open and so that the circuit is closed when the lever is depressed due to the carriages hitting them with just two wires(?). But which pins on the board should these go to? The two outer ones?

EDIT. This is wrong isn't it. The board wants to look at a normally closed switch and see it open when the carriage hits the end.

I think I fathomed this out now, I need the common to go to the "SIG" side, and the normally closed go to the "GND" side correct?
(from interpreting this [www.reprap.org] )

However this seems wrong too... surely the Common should go to ground and the normally closed to signal?!?!



2. Similarly with the extruder heater and bed heater the outside pins?

3. I am hopeful that I can get the PSU connected and turned on OK and connected to the PC, but what software is best to use (I am on Windows 7 64bit if that makes a difference) and can someone point me in the direction of the most relevant commissioning and calibrating guide?

Thanks a lot,

George

Edited 2 time(s). Last edit at 02/29/2012 12:01PM by gsport.

End stop wiring.
These are just switches so it doesn't matter which way round they go, and yes they go to the outer pins the centre pin is not connected to anything.
Extruder & Bed heater.
Outer pins again and as these are just resistors wiring order is irrelevant.
Software.
These are the four packages I am using.
1.Sprinter source code
You will need to alter configuration.h to tune and calibrate the Sanguinololu board.
2.Arduino version 0023
To compile and upload Sprinter to the board. (Sprinter is not compatible with the latest version)
3. Pronterface.
To connect to the printer, control it and send gcode files to it.
4. Skeinforge.
To convert an STL file into Gcode.

Slic3r is another option instead of Skeinforge which has a nicer interface but is not so configurable.

The board supplied with the kit has the heater pins tied together in pairs, so you don't just need to use the outer ones.

I used 4 thinner cables, left over from the stepper motors, rather than 2 thicker ones for extra flexibility.
(Although I should have used ones a bit thicker, as they do warm up a little)

Thanks Glyn that is very helpful.

Thanks Bloomoo, that seems like a good idea, I am a bit worried that my choice of wire for the heated bed is a bit thin so if I have to re-wire I will try this. I got some good thick stuff for the extruder tip but ran out for the bed and used some off an old power supply.

George

ARRRRGGGGGHHHHHH

Having thought that I was just about ready to start connecting the printer to the computer I just had a small package from thereprapkitstore containing two new thermistors "as replacements for the incorrect 2k ones sent out earlier."

Thanks a bundle, presumably this error was spotted a while ago, but rather than email customers to warn them he just waited to inform us with the replacement package... so now I need to break everything down and rip the old ones out and fit these new ones whereas I am betting that this error was known earlier in the week when I was painstakingly fitting the wrong ones...


On the subject of the drivers/firmware and software is there not a website or videos anywhere that walk through the process as thoroughly as the mechanical assembly seems to be covered?

George

George - having just swapped out my thermistors and replaced my melted hot end (after over-enthusiastically using the 2k thermistor), I feel your pain!

To answer your question, there seems to be a consensus emerging that Sprinter (firmware), pronterface (printer control) and slic3r (GCODE generation) are the easiest software packages to use for getting started. Other packages seem to be either poorly maintained, poorly documented or too complicated for us newbies. But this is just my opinion, and you will form your own.

Here is a link to a walk-through with this software combination which some of us have used successfully:

[richrap.blogspot.com]

Thanks Another Reprapper,

Thermistors switched over and waiting for my silicone to dry (really glad I put junction box on the edge of the heated bed and under the extruder plate for these connections).

Busy looking at software and firmware now...

George

George, I second what another_reprapper says.

Just go with Slic3r, Pronterface, and Sprinter to start with.
The default settings work well enough to produce something reasonable straight away, and you can just tweak things from there.

I did try skeinforge, but even after fixing the the common gotcha's described on here and other websites, I consider the gcode it produces to be positively hazardous to my nice new machine!
(I'll have to go back at some point and carefully go through every setting and double check everything)

As for the thermistors, the error was discovered last week in this thread

-Mark

Just discovered where skeinforge keeps its settings (documents and settings\username\.skeinforge) so have zipped up my current settings which work ok for me. Also attaching the start and end files but these depend on my alteration of sprinter to use M190 and M116 see link and your temp settings.

Also attaching image of my most complicated print to date, not perfect some issues with the bridging but I'm quite pleased with it.

Edited 3 time(s). Last edit at 03/02/2012 08:18AM by glyn.

Thanks Mark,

I got pronterface installed and I can move my axes and extruder motor WOOHOO!!!

However I am struggling with Arduino 0023 (which I assume I need to access the calibration files in Sprinter which came pre-installed on the board) Windows found drivers for it and installed them and looking on the device manager I dont have anything that looks like the board apart from a USB serial port (COM7) under ports.

When I run Arduino I can set it to COM7 but the list of boards does not include what it says on my chip (which is ATMega 644p) leaving it on UNO when I try to upload "blink" as a test it says "problem uploading to board"...


I also downloaded Slic3r (0.7.0) and there doesn't seem to be an executable file there to install it.


Thanks for any help.

George

George
You need the Sanguino add-ons for Arduino to compile Sprinter for the board. See the info here:
[sanguino.cc]

You can download Sprinter in a zip file from here:
[github.com]

Btw you can't access the pre-installed firmware but fear not, it is not that difficult to learn how to compile your own firmware to replace it. You only need to edit Configuration.h and thermistortables.h in Arduino. The first goal should be to get the software to compile (by installing the Sanguino add-ons). Don't worry you will soon be an expert!

Regarding Slic3r, did you download the latest zip from here?
[dl.slic3r.org]
There is an executable file inside the relevant zip file.

Good luck and post here if you get stuck.

Edited 1 time(s). Last edit at 03/02/2012 01:07PM by another_reprapper.

Thanks for that.

Slic3r seems to work now.

Got Arduino modified with the sanguino file (just the top one off that list 0023r3) and the board identified and I think that Arduino is happy now...

Are you saying that with the pre-installed version of sprinter I cant edit configuration.h etc? so I absolutely have to reinstall a new version? Or do I just modify the configuration.h file from the sprinter file and "upload"(?) that somehow?
One of the blogs I looked at (Dust's reprap) tells me to edit the boards .txt file so that the upload.protocol=arduino rather than stk500, but when I try to change this within the sanguino folder of the arduino/hardware/sanguino file I cant save the modified version of this file.

I am stumped where to go from here, presumably I do something in Arduino to either "upload" an edited (in notepad) configuration.h or else compile a new version of Sprinter for the board and then edit configuration.h but I am way out of my depth here. I looked at a handful of "guides" to doing this but they all seem to skirt over the actual basics of where and how I do this stuff...

George

Edited 1 time(s). Last edit at 03/02/2012 03:58PM by gsport.

George
Yes you do have to re-install a version of the Sprinter firmware - there is no (easy) way to edit the firmware that was pre-installed.
You need to learn how to compile and upload your own firmware as some critical configuration of the reprap printer is done in the firmware, e.g extruder steps per mm.

But this process is easy, I will explain...

In the Arduino software, after you open the Sprinter firmware (the .pde file in the unzipped Sprinter firmware folder), you can then edit Configuration.h and thermistortables.h in the Arduino editor. No need to use Notepad. These files are documented and you should be able to understand most of Configuration.h.

If you need some help with thermistortables.h, I have attached one which I used today (I edited thermistor 6 and put in a table I generated for a 100k Ohm thermistor with a 4066 beta - which I am fairly sure is the one reprapkitstore have sent out). If you use this you will need to set thermistor 6 in Configuration.h. Note that I haven't yet printed with this thermistortable.h but it does seem to melt PLA with pronterface so I am fairly confident. Maybe someone else will post a thermistortable.h they have used with the reprapkitstore thermistors.

Once you have edited those files, you can press ctrl-R to compile in Arduino (select the target board in the menu). If you have the Sanguino addons installed correctly then it should compile. If not, report back and we'll help diagnose the cause of the problem ( highly likely due to the sanguino addons not installed correctly).

Then once the software compiles, you can press ctrl-U in Arduino to upload it to the board (select the COM port first). This overwrites whatever is on your board. With regards to editing boards.txt with that change - I can't remember but this may not be necessary. If uploading doesn't work then give it a try.

Once you have figured out the process of editing the firmware, compiling and uploading, you will be ready to work through richrap's configuration guide as linked to in the post above.

Thanks Another Reprapper that was absolutely what I needed thanks for taking the time to type all that out.

Got sprinter across to the board with configuration.h edited to the correct board only for now, did a quick movement test and the calibration seems great with the standard values (previously it was out by about 5%)

George

Thanks for posting those skeinforge settings glyn.

I was able to get pretty good prints straight away. (See examples of the oozebane test below)
It looks like they'll just need slight tweaking to tune them for my machine.

-Mark

Hi everyone,

I take advantage of this topic to ask for help. I'm also building a Longboat Prusa. I finished building the structure, wiring everything, screaming at 2am when I got the first move with pronterface and editing the firmware enough to get the right thermistor table...
Now I'm trying to calibrate everything. My problem: I noticed that only for X axis, the endstop, once triggered, does not stop to move even further right but stop moving left. I want to have the opposite effect.
I tried to change the const bool X_ENDSTOP_INVERT = true; but it had no effect.
I checked my wiring, I followed the instructions as on the wiki and I don't have the problem with the other axis. They work just fine.
Any idea?

Thanks for you help.
A repraper from Paris

I think your endstop was behaving correctly but your axis is moving in the wrong direction. The easiest way to fix that is to put the motor plug on back to front, or swap the first two wires.

---

[www.hydraraptor.blogspot.com]

Hi Pierre,

Like nophead says, it sounds like it is the X-axis direction that is incorrect. I had to invert mine as well.

Facing the machine,
the axes should move +X = right, -X = left, +Y = towards you, -Y = away from you, +Z = up, -Z = down

Assuming you are still using Sprinter,
The *_ENDSTOP_INVERT settings change it from normally closed to normally open microswitch.
The *_HOME_DIR control which 'side' of your machine the endstops are on

It is the INVERT_*_DIR settings which change the axis movement directions.

-Mark

Edited 1 time(s). Last edit at 03/03/2012 09:58AM by Bloomoo.

Thanks guys.

For some reason any change that I do to my firmware does not affect the behavior on Pronterface. I tried to change a few line from false to true as a test and upload it to the board but I cant see the change.
I'll try to unplug the motor and change the wires order to solve this. I'll let you know.

Just to make sure. Which face is front? Cause currently, I have the board facing me, the x motor and x endstop on my left and the the Y motor and Y endstop facing away from me. Is this front or back?

Also, since the instructions are quite short on the wiki, could someone show a photo or diagram of how you plugged your heated bed to the board?

Thank you again.

Pierre

Here is a picture of my machine, with a post-it note at the home position....



The the Y-axis end stop is at the back, so the bed hits it as it reaches the home position.
I've also put the heated bed connector at the back, so all the cables are routed the same way.

For the heated bed, I ddin't bother with the separate MOSFET on the bed, and just wired it directly to the controller board.
Have a read of this thread.

I'm not sure why the firmware changes aren't taking effect, perhaps they are not uploading correctly?
Change the
char uuid[] = "00000000-0000-0000-0000-000000000000";
entry in Configuration.h to a new number, and then send the M115 command to make sure it has uploaded.

-Mark

My Y axis was playing up like this but I just moved the micro switch to the other side... not very elegant but very quick.

Got everything working (I think) and about ready to try my first test print?!?!?

Do I just whack strips of the Kapton tape across the bed or is there a system to it?... Ahhh found the tips about soapy water.... Sorted.

Can anyone remind me what size the nozzle is on the supplied hot end? I know I saw it somewhere but cant find it again. Tried measuring some of the excreta (surely cant call it that?!?!) but that seems very variable and quite large...


George

Edited 1 time(s). Last edit at 03/03/2012 07:18PM by gsport.

You may end up with mirror image prints if you have one axis working backwards.

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[www.hydraraptor.blogspot.com]

Ahhhh... good point... I guess one of my first test prints will need to be something handed to check it...


Wondering how long I need to give the kapton tape for the soapy water to dry off... keen to try a print but dont know if using the heat of the bed to dry it off quicker is a good idea....


Also... should I have used high temperature solder to connect my main hot end resistor? It seems to be getting a couple of drips...

Also also... I have a Maplin infrared thermometer which I thought I could use to check the bed and tip temperatures but the readings it is giving me are obviously miles off... any ideas why? reflectivity of the metallic surfaces (this was before I applied the kapton tape...

George

Edited 1 time(s). Last edit at 03/03/2012 07:35PM by gsport.

After you get going one of the first improvements I would do is put a sheet of glass on the bed. This makes life sooo much easier. Just a quick wipe with meths and off you go. Any odd bit of household glass, 3mm will work fine. Just clip on with paper clips. my prusa

I have dried my beds by putting them on a radiator overnight. I have also dried one on my machine leaving it at 50C for a few hours.

I use HMP solder for the heater wires because I have it. I am not sure if its is absolutely necessary when the wires are kept at full length. Solder run close to its melting point seem to degrade over time. It oxidises and crumbles. Crimps are probably the best option.

The amount of IR radiation depends both on the temperature and the emissivity of the material. Black objects have an emissivity of 1 and presumably a perfectly shiny object would be zero. IR thermometers assume a value close to 1 but shiny metals are much lower. The other problem is the aperture size is usually too large for looking at hot ends.

I don't know how good Kapton tape would be as an IR target. It is both shiny and transparent at optical wavelengths, not sure about IR. A BGA rework station that I used at work had Kapton tape for sticking down thermocouples but also a special black tape for sticking on shiny chips to get an accurate IR temperature measurement.

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[www.hydraraptor.blogspot.com]