Upgrade suggestions

I would like to upgrade my 3d printer for my birthday. I want to get into printing with more materials. Especially materials that do not degrade and are inert for use in my aquaponic system. I was thinking a heated bed would be a good upgrade so i can print ABS. Is it worth the trouble? Or would a dual extruder be a better first upgrade?
After all the tinkering with mine, I guess the question would be do you have an immediate need to print with dual colors or dual materials? My suggested order of upgrades would be:

1. E3D V6 (Single or Dual) hot-end upgrade. If you only want to go to the single, you could still print/build the dual extruder frame so that you could add the second hot-end later. Aside from improving the overall bed design, I think the all metal hot-end is the single biggest improvement you can make on the stock GMax. Ray, Christian and others can attest this this.

2. Do the heated bed upgrade. If you go this route do the research first and consider how much work you want to put into it. Meaning, with a heated bed you will need to move to a glass platen (if you have not already) and if you are willing to experiment, there is no reason while you can't put a grid directly on the underside of the glass you would be printing on to cut out the thermal barrier (and weight) of a secondary heated layer.

Just my 2 cents for what it's worth... I will be (hopefully) finishing my move to dual E3D's over the long weekend and can start working on my 3rd redesign of the bed using a direct heated glass platen.

- other Chris
1. YES.

2. Heater Painted directly onto glass pane from home depot. Copper tape and conductive ink. Maintains ~30 degrees with constant 12v input, consumes less than 1 amp due to large resistance of this ink.

I ordered more ink of a lower resistance this time around. Hopefully that will be able to warm an 18" square.
My goal for my large production printers is either a 2' x 4' printing onto an acrylic sheet, or a 30"x36" (the size of the largest glass sheet available at Home Depot), warmed using this method. I would have 2 separate zones though, each one warming half of the sheet. Using this methodology, you can attain any size by making a grid.

I wonder what Chris meant by "grid".
What I use there is Bare Conductive which I got from Sparkfun.

The 'more conductive' ink I alluded to is from fwgltd.co.uk. Just ordered yesterday, could be a few weeks before I get it.

Btw, that pic is of an 8" x 10" glass pane and the painted portion is 8" x 8". What's cool is that the unpainted edges of the glass are still cold (room temp, and it's snowing here) while the painted portion goes up to 33C or so. This means that the printed green clips for mounting and leveling won't be disfigured by heat b/c it's not getting hot there.
By 'grid' I meant laying out the copper tape (or I was actually considering aluminum tape) as a solid continuous trace all along the bottom of the glass in a "search grid" pattern- or basically a snake. This could also be done with a thin solid piece of resistance wire (Kantahl maybe) bent painstakingly into the same pattern and held on with Kapton tape. Don't remember where but saw a guy online who was doing this using an array of stick pins on a cork board to use to bend the wire.

Kanthal is easily available off fleabay and comes in these resistance per inch levels:
AWG 20: Low Resistance (0.07 ohms/inch)
AWG 22: Low Resistance (0.11 ohms/inch)
AWG 24: Low Resistance (0.175 ohms/inch)
AWG 26: Low Resistance (0.28 ohms/inch)
AWG 28: Low - Standard Resistance (0.44 ohms/inch)
AWG 30: Low - Standard Resistance (0.70 ohms/ inch)
AWG 32: Low - Standard Resistance (1.1 ohms/ inch)
AWG 33: Low - Standard - High Resistance (1.39 ohms/inch)
AWG 34: Standard - High Resistance (1.76 ohms/inch)

The ink is a good idea. Had not thought of that. Does is spray on? How is the adhesion to glass?

- other chris
So I am thinking I will go with building a dual extruder assembly with 2 E3D v6 hot ends. One 0.35mm and the other 0.5mm. I chose this because I could build it without messing with my printer too much.

Any suggestions for where to buy parts?

What advantages do the E3D hot ends have over my stock Jhead .35mm hotend that came with the Gmax?
They don't have those sizes. The standard 0.4mm nozzle is fine. Get a 0.6 and a 0.25 if you want (additionally) but I'm doing just fine with standard. I tried a 0.6 and am not using it.

I did a bulk purchase last week, I could have added you in but it's late now.

Compare prices between filastruder and E3D directly. Be aware of foreign transaction fees, conversion fees from GBP, etc...

Superior performance. The difference is night and day.

Chris - I'll reply to you in a bit.


New Member
Ray, if you go to higher temperatures and don't cover the entire piece of glass, the temperature difference may cause the glass to crack.
Very possibly. But at up to 40C, I should be fine and I do monitor the temp carefully when first getting started. I don't believe I need to go higher than that, I'm just trying to overcome the cool room temp. At about 25C glass PLA should no longer be warping due to cold print surface.

I'm not getting borosilicate glass for just those temps. I don't print with ABS either so I don't need to go higher.

Chris - pretty sure Kanthal = nichrome wire and one of those is a brand name for the other. That's what's used inside a toaster so it should work. Just seems tedious.

The ink is actually extremely goopy and I applied it with a roller, formally called a brayer.
Adhesion is fine, just clean with spirits first.


New Member
Can anyone who has both tell me what the length difference is between the normal j-head that the gMax uses and the E3Dv6? From pictures I calculate it to be just over 6mm, but I currently have neither hotend.


New Member
I asked because I was going to look into modifying the fan mount bracket to bring both the fan and the shroud down enough for the e3d. I guess I don't need total length, but length after the mount point.
Search on grabcad, you'll find models for both.

But your best bet is to just measure down from the inside top of the groove mount STL model to wherever your "mount point is" using those dimensions I gave.
I have decided to build a dual extruder assembly completely seperate from my single extruder assembly. I want to be able to interchange them very easily.

Hey Gordan... If you read this. You really need a parts store.

I just bought 2 E3D hot ends and nozzles from Filastruder. I bought steppers and v-slot wheels from open builds. I have 4-40 screws and nuts. Where do i find all the other stuff. Fan, filament toothed wheel and bearing, spring, RJ-45 pcb. I have LEDs i can use too.
I'm actually a distributor for every place you've just mentioned, I just don't have that much stock at any given time for OpenBuilds metal or E3D Hotends (I go through a lot building and developing my printers).

I've got you covered for all the small parts, please reply back or shoot me a message.

Btw- in that last pic are E3D clones from China. Not even worth trying, they jam up in minutes. Genuine is the way to go, and I abide by that fully.

I reply very quickly, in fact this is the longest it's taken me and that's because imgur is slow for me. Awesome, but it takes a while to upload pics.

Looking forward to your business.
I went to Filastruder.com to order my second e3Dv6 hotend and noticed that they have two new hotend products for dual extrusion, the Cyclops and the Chimera. Both look intriguing but seem like they would require significant modification to the current extruder carriage. For starters, the filament entry points are too close together compared to the gMAX. It looks like a Bowden feed would work well with these new hotends. I'm wondering if a Bowden feed would be a poor choice for the gMAX because of the large build volume. The filament tubes would have to flexibly support wide and high axis travel.

But before I plunk my money down for a trusty e3Dv6 I'm wondering if anyone has any thoughts about the Cyclops or the Chimera.