thereprapkitstore.com Prusa Mendel construction Notes/Discussions

Oooooo dev build version of Slic3r, which version you using??

Glad to hear it's all good!

Cheers,

Keukpa

Hi
i am new to building rapid prototype machine. I used to build PC based motion controller with EMC2.
I did build working machine with EMC2 motion controller and it performe well.
I think in rapid prototype it is better to voncentrate on part that not coverd before in other areas.
Building working CNC machine was done and talk about in EMC2 www.linuxcnc.org
Also there are a lot of working CNC mill that can also be use - as a rapid prototype machine.
So, i most interesting part is in head that introduce plastic ABS etc. and genarating CNC code -programming - from 3D solig -surface model.
Thanks
aram
Portland OR

Hey MotoBarsteward,
I finally got a smaller cooling fan and printed off the fan mount you are using. Even though the print quality was very good, I found that the fan and duct do not connect together very well (not at all actually). Did you find it difficult to connect them or is something still off with my printer?

Sorry, I'm not sure I can see what your question is. This thread was set up to allow discussion on a particular machine purchased as a kit from thereprapkitstore.co.uk.

AMTB Wrote:
-------------------------------------------------------
> Hi
> i am new to building rapid prototype machine. I
> used to build PC based motion controller with
> EMC2.
> I did build working machine with EMC2 motion
> controller and it performe well.
> I think in rapid prototype it is better to
> voncentrate on part that not coverd before in
> other areas.
> Building working CNC machine was done and talk
> about in EMC2 www.linuxcnc.org
> Also there are a lot of working CNC mill that can
> also be use - as a rapid prototype machine.
> So, i most interesting part is in head that
> introduce plastic ABS etc. and genarating CNC code
> -programming - from 3D solig -surface model.
> Thanks
> aram
> Portland OR

---

Using ABSPrusa Mendel Zaphod with Pronterface and slic3r 1.3.0. Printing well with 3mm PLA and ABS through 2 x J Head Mk IV b and Wade Geared Exruders. Controlled using RAMPS1.4 board running Marlin_v1.1.9

Not sure what you mean by "do not connect together". When I printed mine, my slicer was still making holes too small so I used M2 nuts, bolts and washers. The duct is intended for use on a 40mm fan. This was not having the desired cooling effect so I've just purchased a 38x38 mm fan from Maplin. However, I'm finding that this fan, being a three wire fan, does not play well with the thingiverse fan control module. It was tight when it came to pushing the duct into the mounting bracket but, after a little filing, trimming and sanding, it went in.

jonathanbyrn Wrote:
-------------------------------------------------------
> Hey MotoBarsteward,
> I finally got a smaller cooling fan and printed
> off the fan mount you are using. Even though the
> print quality was very good, I found that the fan
> and duct do not connect together very well (not at
> all actually). Did you find it difficult to
> connect them or is something still off with my
> printer?

---

Using ABSPrusa Mendel Zaphod with Pronterface and slic3r 1.3.0. Printing well with 3mm PLA and ABS through 2 x J Head Mk IV b and Wade Geared Exruders. Controlled using RAMPS1.4 board running Marlin_v1.1.9

MotoBarsteward:

What version of Slic3r are you using now? You said the dev debug build? I can't find this online? Are you using Windows or Linux? I'm very very happy with my prints now, just the inner / outer hole problem to address

Cheers,

Keukpa

Sorry I should have explained it better. The problem is gaps between the three pin and two pin connectors as shown below


The holes for the bolts were the correct width after a little cleaning, I tried sanding and bending the pins there is quite a bit of difference.

---

ABS Prusa from the.reprapkitstore.co.uk, using slic3r 8.4 and Melzi electronics with sprinter firmware

Don't get me wrong, mine was tight but I guessed it was meant to have a reasonable amount of friction. I only had to clean it up really. Yours looks like it wouldn't fit at all. I printed mine using 0.8.4 but I used nophead's suggestion and adjusted the extrusion multiplier to give the correct wall thickness but the print was quite week then. Have a go at printing with the latest master branch version of slic3r. That appears to print to a much better accuracy.

onathanbyrn Wrote:
-------------------------------------------------------
> Sorry I should have explained it better. The
> problem is gaps between the three pin and two pin
> connectors as shown below
> [i.imgur.com]
>
> The holes for the bolts were the correct width
> after a little cleaning, I tried sanding and
> bending the pins there is quite a bit of
> difference.

---

Using ABSPrusa Mendel Zaphod with Pronterface and slic3r 1.3.0. Printing well with 3mm PLA and ABS through 2 x J Head Mk IV b and Wade Geared Exruders. Controlled using RAMPS1.4 board running Marlin_v1.1.9

Sorry, I thought I replied to this yesterday but I opviosly forgot to press 'Post message'.

I follow the instructions here which allows me to build and use the latest and greatest on the master branch. Obviously, there are risks with doing this but, at the moment, its the only reliable way of getting my print dimensions correct.

The only thing I do is set the default extrusion width to 0.3mm becasue, I find, with my 0.4mm J Head and 0.2mm layer height, this gives really good quality, resolution and strength.


keukpa Wrote:
-------------------------------------------------------
> MotoBarsteward:
>
> What version of Slic3r are you using now? You said
> the dev debug build? I can't find this online? Are
> you using Windows or Linux? I'm very very happy
> with my prints now, just the inner / outer hole
> problem to address
>
> Cheers,
>
> Keukpa

---

Using ABSPrusa Mendel Zaphod with Pronterface and slic3r 1.3.0. Printing well with 3mm PLA and ABS through 2 x J Head Mk IV b and Wade Geared Exruders. Controlled using RAMPS1.4 board running Marlin_v1.1.9

I tried the new slic3r software and printed the mount. I can already see that the gap gap between the pins is much wider. I am currently using a .4mm width and .3 layer height, I will try out your settings this evening to see how they look.

Woo!

Looks like the debug dev build of Slic3r is so much nicer! Can't wait for the full release of this version. Prints are looking soooo nice!

Photo to follow!

Keukpa

keukpa Wrote:
-------------------------------------------------------
> Where you up to? What parts do you need help
> with?

Hi Keukpa,

I've followed the instructions posted on the wiki, [reprap.org] , that lead me up to the end of the frame assembly.
I'm left with the electronics and print bed assembly.

On the list of materials, it says that my kit has the Melzi electronics and on the Prusa Mendel I couldn't find the instructions on the Melzi, so I'm a bit lost.


Many thanks

I wired up my melzi board using the huxley instructions and it worked fine:

[reprap.org]

My x-axis was going the wrong way so I reversed it by changing the wiring order on that particular motor (black, green, blue, red -> red, blue, green black)

I would recommend that you wire it very loosely initially until you are happy that everything is working correctly and only then crop the wires down to size.

One other thing, use thick electrical wires to connect the heated bed to the board, I had some scary smoke appear when I first turned it on because I was using thin wires!

Thanks for the hints jonathanbyrn - I'm not familiar with electronics in general, so I admit I'm quite timid to go wandering on my own, and the instructions being incomplete were a real kick to the teeth.

I'll post the results later and I'll check if I have access to edit the wiki and perhaps add these pointers as well.

chaos_generator - I had zero experience when I started wiring and it was actually okay once I got a bit of confidence.

Start with wiring up the motors but don't tidy away the cables. You then have to tweak the PSU so that it will always stay on:
[lichyetan.blogspot.ie]

Once you have the motors set up then try them out using pronterface:
[reprap.org]

It will only move in one direction until the endstops are connected. Wire up the endstops and then make sure everything is going in the expected direction.

Once you are happy with the movement and the wire clearances, neaten up the wires but do leave a bit of slack, as you adjust your machine you will need it

I hope that helps, if you have any questions then send them on.

Ah ha! A thread for fellow builders of kits from thereprapkitstore.

I'm in the process of building my kit which arrived a week or so ago. The kit had two declared shortages - 30mm of aquarium tube (!!!) and the hobbed bolt. I initially thought that there must be a world shortage of 7mm tube, but my local petshop have a stock of it and gave me half a metre for free...

I have got to the point where I need the hobbed bolt, so it looks like I will be wiping the dust off my power tools and making one...

Has anyone got a reliable method of contacting James at TRRKS? I have emailed him several times and left a comment via the website but it seems he has disappeared again. This is the kind of thing that kills small businesses...

Who else is building a recent kit? How is it going?

Lee

In my experience James only ever replied to an email when I threatened to raise a paypal dispute. Shocking but true.

At one point sometime after getting my kit (luckily complete) I suggested he take a look at this thread to see the bad reputation he was getting, perhaps do something to counter it, but unless I'm mistaken he hasn't posted anything here.

If you need a good hobbed bolt I'd go with the arcol one: [shop.arcol.hu] . I think you may need one of these as well: [shop.arcol.hu] - you can use two countertightened M8 nuts but this is more secure

Martin

I think the only time I got a reply was when I did similar, Martin. He did state in an email shortly before the kit shipped that there were no shortages, which particularly irks me as the aquarium tube is commonly available and the hobbed bolt is being advertised by several places on the web.

It is a real shame as I can't knock the quality of the kit, or the packaging (although clearly the proof is in the printing). The one thing that puts me off ever recommending thereprapkitstore is the abysmal communications. Still, market conditions being what they are I'm sure other enterprising individuals will step up to the mark...

The Arcol hobbed bolt looks good. I was going to have a go at doing one myself and if that fails it looks like a good option. Thanks.

Lee

Hi everyone,

I have just got this kit and so far so good. I have the frame built and setup, but I am having a few problems with the electronics side. On the reprapkitstore products page, it says there is no need for soldering, but I cannot see how to connect the wires to the mk2 heatbed without soldering. I may well be missing something as I am very inexperienced with electronics.

Has anyone else connected up the heatbed, and if so, how did you do it?

Suzanne

Hi Suzanne,
I think when they say there is no need for soldering it only refers to the Melzi board itself. I ended up soldering wires to the heated bed and then screwing them onto the melzi board. The easiest way is to feed the wire up through the holes from the bottom of the heated plate, neaten them with a scissors and hold them in place blob of solder. Use thick electrical wire as the heated be draws 12 volts.

Thanks Jonathonbyrn, I bit the bullet and bought myself a soldering iron today so I now have that in place. I have never used one before so it was a bit messy but after a few youtube clips, I think I got the hang of it.

I used the wiring that came with the kit (green and black wires). Do you think these are thick enough?

I now nearly have everything wired up, but I cannot find any instructions for the ATX power supply. Do you know where these are on the wiki or can you point me to a good resource on the internet?

Thanks for your help.

Suzanne

I am not sure if the green and black wires are thick enough, has anyone else on this thread used them? I had problems with the wires connecting the power supply to the melzi board, so I used thick electrical wire for all the other connections.

The first thing you do with the power supply is wire it so that it is always on. I cannot find a guide off-hand that clearly shows how to wire it up, I will send you a picture of my set up later on.

Just be very careful the first time you turn it on, only send voltage to one thing at a time and have your hand ready on the off switch of the power supply in case something starts burning. the wires should get hot but if you smell something then turn it off!

I just doubled up the red and black wires that came with my kit, they were more than long enough to do this. I've had no problems doing it that way.

Here is a link to making the PSU come on: [www.techpowerup.com]

However depending on the PSU supplied you 'might' need to ensure you have a load on the 5v rail. I just connected some cooling fans. Seems to work fine for me.

Cheers,

Keukpa

Thanks, that is great - keukpa, that link was very helpful.

I now have power so hopefully I can get the rest of the bits wired up over the weekend.

Seems like we are all at a similar stage in the process. I have substituted a non-hobbed bolt in my extruder so that I can get the rest of it built - by which time I'll either have the bolt from James, or I'll have made one...

Is anyone on here going to cement the resistor into the hotend (using exhaust putty - Gun Gum)?

so after three months of dust covering my fully assembled Prusa, i finaly found the happiness to quickly install this Monty Pyhton software. I did not install a new firmware .

Updated my wiki-page with a little software section: reprap.org/wiki/Prusa_Mendel_thereprapkitstore#the_software

Unfortunately i lost that little thermistor for my heat bed. But luckily i have a digital heat gun to blow 60°C hot air onto the bed

First print was a 10mm square pyramid sliced flat at 4mm height. Made with blender. And it was printed in the perfect dimensions


Next print was a sprocket. But this time the y-stepper somehow lost lots of steps. Yet it is fastened to the pulley perfectly... Maybe the y-stepper is broken..


And the z-axis endstop is of bad quality. It already triggers without the clicking noise. With every new print, the z-axis home position is slightly different

roland
a good night from Germany
* www.liebwink.de *

... when printing perfect over a small area and loosing steps over bigger ones, you'll most likely have some issues with friction (maybe dust on the rods?), skewed rods or not enough motor torque.

Check if your axes runs free without the motors attached and/or rise the motor current ...

---

Viktor
--------
Aufruf zum Projekt "Müll-freie Meere" - [reprap.org] -- Deutsche Facebook-Gruppe - [www.facebook.com]

Call for the project "garbage-free seas" - [reprap.org]

don't need to mention that James did not answer my email

But problem solved [youtu.be]

I switched the stepper/endstop connectors to learn that the mechanics is not the problem.
Than google found me another poor guy with the same problem.
Now i have installed a HUGE cooling element on all four stepper driver chips
and happily printed my first pulley



Also want to screw the two mosfets and the power regulator into the cooling element. But do not know yet, if the back sides are allowed to be short cutted.

Going to buy a new stepper driver. The Pololu drivers are said to be better:
[www.ebay.de] Maybe you have a cheaper source.
I also need another 100k thermistor to enable the heatbed. Still have not found my second one.

Updated my wiki page: [reprap.org] but no surprise, that no one else is contributing his knowledge..
you're living in a toy world..

roland
[youtu.be]

Edited 3 time(s). Last edit at 08/28/2012 02:41PM by roland.

Nice, looks good, I have fitted cooling fans to my board to give a good amount of cooling, but those look awesome! How did you secure them to the board, chips?

Hey guys,

I am another lucky(?) owner of a reprapkitstore Prusa mendel. Another receiver of no emails from James, and another receiver of a partial kit (endstop switches are missing but meh).

I have managed to get the kit pretty much together mechanically, I am just waiting on some springs for the Z-axis backlash mechanism. So I've moved on to the electrics. I have soldered up the heatbed and am about to hunt out some instructions for modifying the power supply.

However in the process of fishing the Prusa out from under a sea of empty sealy bags I have lost a thermistor. Anyone know which one I need? Roland says its a 100k one but does the brand/model matter? I assume the temperature gradients/curve vary and are programmed into my (Melzi) electronics board's atmega? Id rather not have to change anything in there unless absolutely needed.

Cheers

Clem