Ultimaker Original Upgrades

[bhowiebkr 0]

I’m planning on a bunch of upgrades to the original ultimaker and looking for some thoughts and opinions on things. The biggest requirements are printing ABS and managing the fumes.

Heatbad

 

• 
  I’m looking at the one ALU Heatbad MK3 here: http://reprap.me/heatbed/alu-240.html It can take either 12v or 24v
   
  
• 
  I’m thinking of getting included the temp sensor, glass and insulator.
   
  
• 
  I’ll need an external power supply but should I go with 12v or 24v? what is the max power requirements I should look for.
   
  
• 
  What is the best way to drive the output from the power supply. Can I use a big power mosfet? or should I go for ones of these all in one boards: http://reprap.me/heatbed/power-expander.html
   
  

 

Heat Chamber

 

• 
  I’m going todo something similar to this: http://www.thingiverse.com/thing:88456
   
  
• 
  I have two cats and one loves wires so I need to enclose this thing.
   
  
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  I’m in an apartment so when printing with ABS I need to vent the fumes.
   
  
• 
  A small PC fan to create just enough negative pressure that could be used to draw out the fumes of the chamber while not cooling the chamber down too quickly.
   
  
• 
  putting a blown out candle inside the chamber I think can be used for testing air leaks and negative pressure.
   
  

I know there are many more countless upgrades I’ll do but these are the two bigger ones I’m planning first.

 

[tommyph1208 55]

Hi

Did you consider the complete alu heated bed kit from ebay:

http://www.ebay.com/usr/3dprinting_hk

There is a borosilicate glass kit to go with it, and the seller also has power supplies.

I have the kit, and I am really satisfied with its apparent quality and looks:

I still have not totally completed my rebuild though, so havent printed with it yet, others have though, you can read a lot more about it (and heated bed solutions in general) in this thread:

http://umforum.ultimaker.com/index.php?/topic/2771-complete-heated-bed-kit-for-ultimaker/

If you are set on the RepRap heatbed, I would:

- Go for a 24V PSU large enough to drive both heatbed and printer.

- Wire the heatbed up to the 24V via relay controlled by the board heatbed mosfet

- Wire the board up to the PSU through a DC stepdown buck, dialed at 19V output.

 

[bhowiebkr 0]

I just ordered it! I got the glass heated bed and power supply. I’ll do the 3-point leveling mod on it too.

 

[gr5 2,173]

You can't wait one hour for suggestions? Jeez.

That *is* a good kit though.

For now you can put a cardboard box on the top and saran wrap on the sides. Once you get the heated bed.

 

[bhowiebkr 0]

Haha couldn’t wait. Well I got the missing bearings I needed to complete the ultimaker original build. I’ve started printing some parts with mostly success and one failure. See the album I just put up

.

 

[anon4321 16]

LOL, he waited a whole 37 minutes before pulling the trigger. I have the rev 2 of that kit. I think jason is on his third iteration that has a thicker alu plate and an even stronger connector and stronger relay.

I recommend you look for a solid state way of switching it on and off. Jonny who I believe is a electrical engineer came up with cheap circuit using a MOSFET, see http://umforum.ultimaker.com/index.php?/topic/2771-complete-heated-bed-kit-for-ultimaker/?p=58402

For an off the shelf but a little pricey solution, I went with a SSR for 30USD. See http://umforum.ultimaker.com/index.php?/topic/6014-heated-bed-build-and-a-question-about-the-z-stage/?p=55276

Just note that the UM1 control board can NOT switch that much current directly due to limits of the traces, the power switch and power connector. So usually, the on board MOSFET is used to drive something external like a relay, SSR or the MOSFET in Jonny's circuit through a separate power supply.

 

[jonnybischof 60]

I'm working on a little improvement of my circuit at the moment:

Don't look at the pictures too exactly, I made a pretty dumb mistake on that one so it doesn't work yet. But you get the idea

Will upload it to Youmagine with complete BOM when it's finished..

 

[anon4321 16]

Did you 3d print that circuit board? LOL! If you are going to that trouble, you should engineer in little races to set the wires in. If you get really tricky, you could have small bridges in key places that you could stuff the wires under or little tabs you could reheat and fold down to capture the wires....

Is that XT?

 

[anon4321 16]

Jonny, your next mission is to design the following (I already have but want to see if I'm correct ;-) ) -

 

On one side is a 3 pin connector that goes to the nozzle temp sensor input on the UM1 shield On the other side is an input from the nozzle temp sensor. In between, a LM339 is sampling the temp input which is passed unchanged to the other side (can be powered from the 5V on the sensor input on the shield). When the temp signal goes above the the value set by a potentiometer, the comparator output drives a (small) MOSFET which pulls a line to ground. The other side of the line is connected to the heatsink fan and the other lead of the fan is connected to 12v, 19v or 24v as required.

 

Please be sure to -

Incorporate hysteresis so noise does not cause the fan to go on and off without a sufficient change in temp (say 5C).

Support both thermocouple and thermistor type sensors.

Probably should incorporate an area for a pull up resistor for thermistors or even a jumper to enable it if it is populated.

 

Additional note: the design should lean towards a low temperature setpoint of about 40C so the heatsink doesn’t absorb too much heat before the fan comes on.

 

Please show all your calculations as they will be more than 74.12452876% of your grade….

 

[jonnybischof 60]

Did you 3d print that circuit board? LOL! If you are going to that trouble, you should engineer in little races to set the wires in. If you get really tricky, you could have small bridges in key places that you could stuff the wires under or little tabs you could reheat and fold down to capture the wires....

Is that XT?

 

That's exactly what I've done

There's races on the bottom for the component legs. I've even drawn component outlines on the top of the "PCB". It's just not visible because it's only 0.3mm high.

It works really well because the component legs are stiff and hold themselves in place when you bend them into the tracks. Now I just have to improve some details about the design, then make a top and bottom cover and we'll have a completely "integrated circuit". A bit bigger than other ICs, but basically the same thing

/edit:

Yes, it's XT. Had it in the printer at that moment..

 

[jonnybischof 60]

Jonny, your next mission is to design the following (I already have but want to see if I'm correct :wink: ) -

 

On one side is a 3 pin connector that goes to the nozzle temp sensor input on the UM1 shield On the other side is an input from the nozzle temp sensor. In between, a LM339 is sampling the temp input which is passed unchanged to the other side (can be powered from the 5V on the sensor input on the shield). When the temp signal goes above the the value set by a potentiometer, the comparator output drives a (small) MOSFET which pulls a line to ground. The other side of the line is connected to the heatsink fan and the other lead of the fan is connected to 12v, 19v or 24v as required.

 

Please be sure to -

Incorporate hysteresis so noise does not cause the fan to go on and off without a sufficient change in temp (say 5C).

Support both thermocouple and thermistor type sensors.

Probably should incorporate an area for a pull up resistor for thermistors or even a jumper to enable it if it is populated.

 

Additional note: the design should lean towards a low temperature setpoint of about 40C so the heatsink doesn’t absorb too much heat before the fan comes on.

 

Please show all your calculations as they will be more than 74.12452876% of your grade….

 

Excellent idea!

I will definitely integrate that into my UM black edition electronics! With my "PCB" method, even these a bit more complex circuits should be easy enough to do by hand.

 

[bhowiebkr 0]

I don’t have the heated bed yet but the one I’ve gotten shipped comes with a small board that drives a relay for switching the bed on and off. It’s probably not too loud compared to all the other stuff I have attached like stepper fans.

Under the frame I have 12v bus using 4 LM7812 for max 4 amps total. They are powering 4 stepper motor fans and some LED lighting. I need to get another aluminium heatsink to help disperse the heat from the regulators, maybe split the thing in two.

I have got all the windows on the frame all enclosed with plexiglass I should have some photos soon.

[jonnybischof 60]

Why don't you just use some DC/DC converter module?

They have around 87% efficiency and don't get hot...

 

[bhowiebkr 0]

Like a switching power supply? I should change it to that in the future, It's just I have a whole bunch of 12v regulators from other projects doing nothing

 

[tommyph1208 55]

Like a switching power supply? I should change it to that in the future, It's just I have a whole bunch of 12v regulators from other projects doing nothing

 

I think Johnny means one of these:

http://www.ebay.co.uk/sch/i.html?_trksid=p2047675.m570.l1313.TR2.TRC0.A0.H0.Xdc+dc+buck&_nkw=dc+dc+buck&_sacat=0&_from=R40

I use that for 12v as well...

[bhowiebkr 0]

Here’s some photos of things I’ve added to the printer. The fumes were becoming a problem for me even with printing PLA but with this setup that’s no longer an issue. Unfortunately the AC fan is far too strong for this, so I’ve been looking into what can be done to adjust it. The AC fans speed is set by the frequency of the AC line and variable frequency drivers are expensive so I’m thinking about having an adjustable vent at the top that can be used to bleed in air. That way I can keep the bottom of the chamber heated better. The cross flow fan approach might work well for this setup

 

[bhowiebkr 0]

I ran into another problem the vibration from the exhaust fan was shaking the printing surface too much causing bad quality prints. I have a Sorbothane sheet that I’ve cut some corners to prop up the plexiglass top with. The sorbothane completely isolates all vibration from the fan and also leaves an air gap between it and the printer for less air turbulence in the printing chamber.

 

[LePaul 321]

Did that http://www.ebay.com/itm/Borosilicate-Glass-Add-on-Kit-for-Ultimaker-Heated-Bed-kit-Reprap-3d-printer-/161309237571?pt=LH_DefaultDomain_0&hash=item258ec7a143 come with a power supply?

I like how you sealed up the printer. I have wanted to circulate the air to knock down the fumes as well too and was thinking of a basement-window mounted fan, similar to a bathroom fan.

What changes were needed to get the plate into the build platform? Any difficulty leveling the bed for printing?

 

[bhowiebkr 0]

I order 3 things from the seller. The power supply. The heated bed comes with the relay board and a resistor you need to solder. The power supply is a Meanwell S-350-24. The heated bed has the same holes that the stock acrylic bed has. When I installed the heated bed I drilled out the threads of the black plastic mounts and epoxyed them into the wood. Leveling the bed is now done under the Z-stage because I’m no longer able to get to the top for leveling.

When mounting a fan on the top, you’ll need to find a way to isolate the fan vibration from the printer. In my case I used several layers of Sorbothane in the corners of the plexiglass top box where it rests ontop of the printer.

The fan I used was from home depot This is a 70 CFM but I think something less than half that would serve better.

 

[LePaul 321]

I was thinking a case fan used in a PC would pull up enough airflow....thanks for the info