The Longer 3D LK1: Unboxing and Build
In this article we unbox the longer LK1 and will walk you through the setup.
The instructions come right on top, the box we got was in rough shape, but the unit itself was okay.
This printer boasts all metal construction. They are talking about the different brackets and braces, there are no plastic parts. The spec sheet said that it came with an ac heated bed, but it is actually PCB heated.
Unlike the CR10s the LK1 is a 24-volt system, aside from the heated bed. Since the heated bed is heated by a standard PCB heater, it would also be 24 volts, just like the rest of the machine. I’m not sure why the spec sheet said ac heated bed.
The bracket on the front is an anodized or power coated metal. It does feel like plastic, but I took a knife to it and it is definitely metal. Just a side note, this unit comes with a splash of colour. On our unit all the brackets were blue.
They way they attach the heater to the heat bed is similar to the CR10 Mini. It had a removable molex style connection and it has a positive lock on it and an aircraft connector on it like you see on most models.
Going further into the box, you will find the control box and the connectors for the heat bed and the hot end assembly. The assembly components and tools are in their own smaller box, and the uprights are at the bottom of the box.
In the box of components, you will find a scraper, reinforcement brackets for the uprights, some nice flush cutters, Allen keys, a USB cable, power cord s card and a USB read for it, a spool of 1.75mm PLA, and a spool holder.
The bed surface is held on with binder clips. It appears to be 3mm glass and a poly carbonate material.
The included PLA prints at a range of 200-240, which is quite the range but on the high side.
Compared to the CR10s and Tevo Tornado
The control box is rather large, compared to the CR10s, but it does have a 3.2-inch full colour touch screen. The uprights have blue accents like the brackets for the base.
It is a single Z lead screw, like the Tevo Tornado, though it doesn’t have a 3 to 1 geared kind of tighten style extruder like the tornado does. It does have a filament run out sensor, it seems to be a contactless sensor which is neat. It is bolted to the unit, not a press fit bracket like the CR10 series.
The build volume is 300x300x400, like the CR10 and the Tevo Tornado.
The hot end assembly of the LK1 is very unique. They used a radial fan for the part cooling fan and a 3D printed shroud on the bottom. They really should use a 3D printed axial fan, we know that they have higher CFM and pressure readings, that’s why things like the creality CR10s Pro are using those now.
Initially looking at the hot end itself, it seems pretty generic and similar to the CR10s.
(Check out our review of the Creality CR-10s vs. Creality CR-10s Pro)
Facing the front of the printer, the Z-min switch goes on the left. The same as the Z lead screw and the extruder. Take the longest M5 bolts and slide them up into the bottom of the base rails to attach the uprights.
The best way I have found to do this is hang one side of the base off the desk and access it from below. Leave the bolts a little loose at first to allow for adjustment if necessary.
Once you have the uprights secure, attach the support braces. As mentioned above, the one with the end stop goes on the same side as the extruder. Instead of using T-nuts to attach the braces, they have tapped the extrusions. So, use the M4 bolts to secure the brackets where the uprights and the base meet.
Attach the controls box to the printer. The z-min attaches to the end stop at the bottom of the bracket. The Y-motor attaches to the back of the unit. Y-negative is the limit switch for the Y, also at the back, and Z-motor is for the Z-stepper on the left-hand side of the printer.
There is an aircraft connector for the hot end components, make sure to alight the pins right and then screw it on the back of the box. The heated bed is the other aircraft connector, the one with only four pins.
Finally, the last bundle of cables goes to the X-motor, the extruder motor, which is on the back bracket by the lead screw. Next is the X-negative (the X-min limit switch) which attaches behind the bracket on the left, and then the E-negative which attaches to the filament runout sensor.
I’m not a fan of the corrugated tube. I wish they used the braided sleeving, it’s just a lot quieter and more flexible.
The Control Box
Before attaching the control box to the printer, we looked at the board that powers it.
There are three screws on either side and the base plate actually wraps around the back and there are four bolts back there as well. Inside is a 360-watt, 24-volt power supply with an interesting shroud to vent it out the side of the case. The fans blow out of the power supply and therefore exhaust right out the side.
On the lid, you can see the touch screen is attached by a ribbon cable. There are heat seats on each of the drivers, a heatsink on the SD card reader, and a very large MOSFET for the heated bed. It might be nice if it was separate, because those tend to fail and are easier to replace that way.
The touch screen is great for navigation and control. On the menu, under settings, you can find a few pages of settings which you can customize.
The hot end cooling fan is very small, and probably makes a lot of noise. The hot end itself is an MK8 hot end, nothing else of note. Make sure to check the eccentric nut on the bottom wheel, the one on ours was very loose. There are also screws holding the X-gantry to the upright, probably for shipping. Make sure to remove those screws.
Once the unit is built make sure to check the wheels are tight enough that they all make contact with the rails and move in sync.
Once the wheels and the bed are tightened down, and you don’t have to worry about ramming the nozzle into the bed, you can start the bed leveling procedure.
On the touch screen, select move head and then home all axes. Next, from the home screen, select more and then leveling. You are able to select each quadrant and make sure they are level, do so one at a time and then finally in the center.
During our leveling, we noticed the center was always super low and gave up on the stock glass and build surface. We used a different piece of glass we had on hand and were able to level it just fine.
Check back with us later to see out calibration prints with the LK1.