3D Printing

I have an Ender 3 V1, so take this advice with a grain of salt.

I can't tell you if the deal is financially good or not, what I can tell you is what my printer is like and if it has problems.

I've had my Ender 3 since 2020, and it's been both a reliable work horse, and a un-reliable eWaste depending on the week, and how much work I need to do on it.

Out of the box it will work well enough, but without a bed leveler it was difficult to get a good first layer. You have that so you pass the minimum hardware requirements. The other upgrade I bought for it was a silent board upgrade (which you might already have) and a all metal heat break. If you don't have a all metal heat break, you will need a roll of PTFE Tubing since the end in the hotend will char and the filament will jam over time.

PEI Sheet is good, though if you print with high temps you may want a glass or a G-10 print bed. PEI Stick like Glue to PETG and will rip and destroy your bed.

As for my issues with Printing on the Ender 3. Well the Bowden system will cause for minor inconsistencies across the X-Axis. It took me years to find this out and another printer from Prusa to narrow this down, however it only impacts tiny parts of a print, and the variance is like +-0.005mm. Most people don't need this level of accuracy so it's fine, especially if it's your first printer.

Another issue I have with the auto bed leveling is the accuracy on the level. It only gives you 2 decimal points of accuracy 0.01, however the properly level my bed I found I needed 3, so manual bed leveling might still be required for you. Since I am always too close to the bed, or no close enough while printing.

With my grievances aside (a good 3D printable model will account for a lot of these faults), I don't hate my Ender 3. the CR-Touch allows me to use beds made out of other materials, rather than steel bed only that I get with the Prusa Mini. I've repaired this sucker more time than I can count, from belts to hot ends, to nozzles and more. And all the parts are easily obtainable from Amazon or even locally at my electronics store.

I personally consider the Ender 3 a hobbyist printer, I've personally expanded beyond printing for myself, so I needed something more reliable. But if you aren't printing day in day out 365 days a year, then it's a solid reliable machine which you will need to tinker with time to time, that is repairable with easily accessible parts. And for the price is cheaper than the alternative.

But there is a reason most print farms and printers use Prusa and (hoping for the long run for these folk) Bamboo Labs.

Check the price of each items. From my memory, Rapido, CRTouch and SKR3 and you are in the 200USD range already. I freaking love klipper but you need a raspberry to make it run. Does it come in the deal? Or at least the sdcard with the configs? Can the person can show you it working?

That's actually a really good deal if the printer doesn't show any signs of physical abuse. There are videos available that discuss how to put the original machines together, and this information is still helpful in showing you where key problem areas might occur and things you want to check before trying to use a used printer. At the top of the list I would suggest making sure the frame is square, the X gantry (the one the print head rides on) is square to the rest of the frame, and that the eccentric nuts are all adjusted (these are part of the rollers that allow the X, Y, and Z axis to all slide freely).

A couple to get you started out with -- these are for the original version of the Ender 3 but most of the information will still directly apply to the v2 machine. Ender 3 assembly: https://www.youtube.com/watch?v=me8Qrwh907Q Bed leveling: https://www.youtube.com/watch?v=5eqTmb01cBk

The information about bed leveling is critical even if you have an auto bed-leveler. You still want to know how to keep the bed reasonably square to the rest of the frame or the ABL is going to be constantly adjusting itself even for simple prints. One of the key mistakes most people make is to leave the springs (or in your case the silicone spacers) too loose which allows the leveling knobs to freely turn while the machine is printing. This is what causes the common issue of "I have to re-level my bed after every few prints". When done right, you can easily go 6-12 months without ever having to touch the bed leveling. In my case with still using the springs, "done right" means you get all the leveling knobs tightened all the way, then adjust the Z switch to match that position, THEN proceed with leveling the bed. A lot of people just leave the Z switch where it's at and adjust the leveling knobs to that level which results in springs that are very loose.

As far as the printer itself goes... I've had my original model Ender 3 Pro for 4.5 years now, pumped out a lot of prints over the years, and still find it more reliable and giving better print quality than the $2500 printer we have at work which has auto-everything and still somehow fails. Plus I personally really love how easy it is to do upgrades on this printer which allows me to customize it to my own needs. Even my direct-drive print head was 3D printed!