New here - please go easy

[Crastney]

Afternoon,I'm new here and would like some advice. not of the 'you should have bought a different printer' type advice either!so here's where I'm at - the wife designs and makes jewellery, and she decided to invest in a 3d printer to make her own. she went online and bought one, about 18 months ago, and never got round to setting it up. a few weeks ago, half term here in the UK, we got the box out of the cupboard, and opened it, to find that it is basically a kit that you put together yourself, it's a CTC DIY I3 - I think it's a copy of an I3 Prusa, but not sure.I had to find three different you tube videos to work out how to build the thing, it had a 2 pin plug, which I'd put in a shaver adapter by accident, which blew the fuse, so I rewired to a UK plug. I had to do some calibration, and realise that I had to tell the software which material i was printing in, and anyway, eventually got a print.but the print has horizontal lines on it. I've done a cube, an XYZ cube, a 14 sided bead, and 3dbenchy, and they all have these lines. they're slightly less in one axis than the other, only x/y axis, z is ok. it's like it lays one layer, then shifts ever so slightly for the next then again, and then a few layers later it resets back to the start position. so it's creating a saw tooth like edge profile. I've added pics at the bottom of this post.I thought maybe it was the belts on the X/Y axes, so I tightened them all up, but then the motor slipped on the x, so I loosened it off a bit again.I've done some internet searching for the most common issues, but this doesn't appear to be one...!I've not done a step calibration yet.any help gratefully appreciated!Flickr Album

[curious aardvark]

you've actually said the problem.

the belts slipped.

You need to tighten the grubscrew on the stepper motor gear.

They don't slip, but the drive gears/cogs/pulley things can often work loose.

And for the record it IS an original prusa i3 design.
With a bit of work, it's a really nice little machine.

If it's got the plywood frame and the crappy control panel with buttons - I've got it's twin sitting on top of my filament cupboard.
Awaitign the day i get round to fitting a 32bit board and touchscreen to it.

I do recommend fixing it to a solid flat surface. Mines bolted to a sheet of 5mm aluminium. But anything solid and flat will work.
reason being the xy gantry really isn't attahced to the print bed very well. So that can recult in uneven bed travel.
So bolt it to something solid and flat.

Other than that and the horendous screen and controller board - the firmware of which you cannot update or change in any way. - hence the new screen and board.
It's good kit.
Mechanically and design wise it's a good machine. Just let down by the electronics.

I did do some porints with it - primarily to see what you could do with s sub £100 machine.

Reminds me - is it one of these ?
https://3dprintboard.com/showthread....100-3d-printer

if not ignore what I just said :-)

[Crastney]

thanks for the reply. yes that's the same printer. I'm sure it will get better than it is now.
the gear/belt slipping was different to the z axis banding.

I was printing a benchy, and I heard a horrible noise, and the motor was turning and the belt wasn't moving. afterwards the printer carried on printing very offset on the x axis. I used Cura to pause the printing and move the axis back, but when I un-paused, it carried on (in the wrong place). I suppose I could have homed it, but didn't think of that. I loosened of the wing nut holding the belt tight, and it then didn't 'slip'.

I've read your other thread, most helpful. What would you say is the one biggest thing to check? or importance of order to check things? If you've seen my pictures on my flickr - they show quite serious z banding - I've put some more photographs on the album.

The base layer seems to be doing something odd - there should be writing, but it's smooshed flat. would that be a z offset thing? or to do with the bottom layers, or the temp of the bed?

The frame for the y axis looks to be bent too - is it worth taking the whole y axis frame apart and rebuilding with sturdier ends, and making sure it's at right angles too?

[curious aardvark]

yes to all really.

While this is an original prusa design, there isa reason it was the cheapest printer you coud buy.
I believe the z banding - and yes it is horrendous - is either because the two sids of the x axis gantry are not perfectly level, manually turning one or other of the z axis screw threads can fix this. Or the actual extrudr carriage just oscillates forwards and backwards.

I pretty much stopped playing with this when I ordred the new board and screen and then I got the sapphire pro and I've only got limited room at that end of my workshop, so haven't playd with it since.

There are thousands of mods and addons on thingiverse - so it's worth looking through them.

Or there is autowiz's approach - and just gradually rebuild and replace pretty much everything.

While - with enough mods - this can be a decent machine - realistically, it's a 'teach yourself 3d printing' machine, that really does need a lot of work.
I never really got to the bottom of the z banding.
Adding caps that held the z screws in place - made it worse.
And you can see the whol extruder assembly swinging back and forth as it prints.

But I just didn't have enough money invested in it to persevere, once I'd got something better to play with.

Not sure if autowiz called his printilicious or it was the base for his 3-in-one project.
But drop him a pm - he's done more with the basic a8 design than anyone else I know :-)

[Axl_Myk]

What temperatures are you using?

[Crastney]

off the top of my head, I think 60 for the bed, and 200 for the PLA. I've not changed them from the default settings.

I'm going to print a hollow cylinder/pipe to see if the banding is level, specific amounts on x or y, or if it forms a spiral around the whole print. There might be one side which is perfectly flat.

I might also film it while it's printing to see if I can see where the issue is...

[Axl_Myk]

Try 215º. 60-65 is good.
I use 65 for the Ender mag mat, and 60 for glass.