# Specific 3D Printers, Scanners, & Hardware > CTC 3D Printers >  Multiple oddities

## TiredJuan

As you may have guessed: I'm new to 3D printing and I'm having issues with my printer. I've done several bed levelings, many many configuration changes, and googled/browsed forums for a few days now. Print qualities have improved only slightly since my first trials, the only thing I managed was to get the second extruder head to stop dragging through my prints.

Printer: CTC Bizer (Dual Head) (I think, it was given to me as a gift, and purchased from an ebay seller without much real data)
Firmware: 7.2 (preinstalled, and reported by ReplicatorG)
Software: ReplicatorG (MakerWare won't successfully print, connects but printing head drags through print)
Settings:
Extruder Temp: 185C-230C (Usually 195 or 200)
Bed Temp: 55C-110C (Usually around 60-65)
Infill: 10 (changing higher and lower doesn't seem to matter)
Layer Height: 0.27
Number of shells: 1
Feedrate: 30 (Just tried 20, doesn't seem to improve much)
Travel Feedrate: 30-90 (Doesn't change much, except minor print time improvements)

The problems are many, but I'll start with the basic ones and move up if we can solve these:
Problem 1: When extruding the "raft" it rarely comes out in good shape (See image 2)
Problem 2: Likely because of problem 1, the first few layers of an object aren't square/don't adhere well? (Happens at all temps/settings)
Problem 3: Objects won't print without raft (printer head seems to drag through them, but they stick up a little almost like it wasn't pressed down into previous layers)
Problem 4: Layers appear to drag/deform As seen on the little stick guy, and the octopus.

Upper layers tend to do better, but not always.


20151228_093614.jpg20151228_112212.jpg20151228_122238.jpg20151228_122032.jpg20151228_125205.jpg

Any help would be much appreciated.

(Note: I work nights, and will be sleeping soon I'll also still be browsing the forums to see if I can find a solution or more info)

----------


## Alibert

Looking at your raft, the tip of the nozzle is way too high over the bed for the first layer. You can see it spiralling and only the lower curves of the spiral are clinging to the bed.

 Have you done the levelling procedure with a piece of paper between nozzle and the bed?

----------


## TiredJuan

Indeed I have, 5 or 6 times now. I thought it was supposed to spiral like that? The head movement appeared to reflect the spirals/squiggles. I'll do it again.

----------


## Alibert

No, it should put down perfectly straight lines which are partly squished to the bed (resulting in a 'D' shape cross-section with the flat side to the bed).

----------


## TiredJuan

This is good to know, thank you. I noticed the leveling procedure is a bit... inaccurate? Moving two screws at a time produces some poor results if you ask me. I releveled, and am printing a test print. Thank you for your help so far.

----------


## TiredJuan

20151228_140023.jpg20151228_140001_001.jpg
Good, but not great. The raft came out much smoother, and the print is much better overall. Still a little goofy in the bottom layer or two!  The top has a little ripple (but not really enough to complain about.)
Also, notice this corner (left side of both images)? It's like that only in this corner of the print, but it happens on each print in this object.

Again, thank you for everything so far, it's already doing so much better.

Any ideas on these layers now? The picture is a bit hard to see, I'm still waiting for the print to cool so the removal doesn't damage or skew anything.

Edit: For those who were wondering, what I did was use a thinner piece of paper. Like that out of a small notebook. I had previously used a piece of printer paper designed for a laser printer.

----------


## Alibert

The raft is looking fine now.

What remains is to get your temperatures and extrusion right.

Be aware that the temperature that is measured may not be the actual temperature. Depending on the tolerances of the components (and possible downright firmware errors, notably in chinese models) the actual temperature can be off by several degrees (extremes of 20 have been reported).

If you have a temperature measuring capability (lab/multimeter for example), you can first check the heated bed. It may be off too much resulting in too high temps for the polymer you are printing with.

As to the nozzles, there are several multiple-temperature test objects to be found on thingiverse, or you can just print your cube at progressively lower temepratures. For the latter, try going down by 10 degrees at a time. I have found that I could go down to 170 C for PLA on two of my printers and still get good extrusion.

Another possibility is that your slicer settings as to extrusion rate need to be modified as the pictures seem to suggest that it is over-extruding a bit. In your slicer you will find settings for extrsuion multiplier, or you can adjust the diameter of the filament a bit which accounts to the same thing. The slicer uses the diameter of the filament to calculate how many mm of filament to push through the nozzle when moving and laying down plastic. If you decrease the diameter, the slicer will push more mm's (extrude more plastic) and if you increase the diameter setting the slicer will push less mm's (extrude less plastic). It is good practice anyway to always check your filament for actual diameter with digital calipers. The cheap ones you buy at the hardware outlet are good enough for this purpose.

Alternate optimizing printing temperature and filament multiplier/diameter until you get good results. This will give a good reference point when testing other colors/brands of filament. For ABS and PETG you will also need to find specific settings which work well. Most slicers will allow you to save settings for a particular type of filament, so you can quickly revert to another filament when needed.

Also beware that there is a dependence between printing speed and temperature. At higher temperatures the viscosity of the polymer will be lower (less backpressure) resulting in more oozing at lower printing speeds but good results at higher speeds. When you increase the printing speed, you will also need to increase the printing temperature a bit, and vice versa.

With lower printing speeds you will generally get more detail and more true dimensions.

PS: as to the paper levelling, did you do it when the heated bed was up to temperature? If the aluminium is thin, it may buckle and thus add/decrease the height at printing temperature.

----------


## TiredJuan

Thank you so much for everything, I'll head back to changing temps and testing different options/programs (Makerware works now, which is a noted improvement.) Again, I can't thank you enough.

Edit, sorry I missed the PS: I did the last leveling with the bed heated. It was around 50C, as thats not hot enough to burn me quickly and close to as warm as the bed gets when I do actual prints.

----------

