Kraken - Revolutionary Bambu Lab AMS HT

Notice!

This is only compatible with the AMS HT. Please view my other designs for designs supporting other AMS systems, there are plenty.

Support

All my designs and mods on Printables are free to use and remix. They have a non-commercial license. If you enjoy this or any of my other designs you can send me a small donation using the link below. Thanks :)

https://www.paypal.me/humebeamengineering

If you send a donation be sure to mention "Kraken - Revolutionary Bambu Lab AMS HT" in the comments box and you will be added to the list below.

Official Supporters

If you have donated $5 or more you will be added to this list as an official thank you from me and you will also be assigned a serial number, the list will be updated as often as possible.

If you've bought Kraken - Revolutionary Bambu Lab AMS HT from one of the authorized resellers you can also request a serial number by submitting a proof of purchase.

• Hume Beam #0001, Hume Beam #9999

• RifRaf #0002

About

Kraken - Revolutionary Bambu Lab AMS HT is an enhanced drop-in main body replacement for the Bambu Lab AMS HT.

The Bambu Lab AMS HT internals are used, you just need to move over the parts.

Kraken - Revolutionary Bambu Lab AMS HT supports all standard functions such as heating, venting, RFID support, filament bypass etc. but with these improvements:

• "Compact Python" - Uses Python tech but inside stock AMS HT box

• Compatible with all types of spools and sizes, up to around 70 mm wide.

• All spool diameters fit, from tiny sample spools up to 202 mm diameter spools.

• No need for spool weights.

• No need to rely on roller grip or worry about stuck spools.

• High torque self-centering double helical gears.

• Fully supports RFID.

• Perfect for odd-sized spools and cardboard spools

• PTFE filament guide that automatically adjusts to the remaining filament on the spool. This curved PTFE guide ensures correct entry into the feeder and it has a range of 20 degrees, meaning filament entry is always optimized. This sorts the issue of near empty spools when the AMS throws a code, pauses and can't feed filament forward as the angle is too steep.

The name Kraken is inspired by the mythological creature from Norse Mythology. I have other designs with names from Greek mythology (Hydra / Python / Icarus / Hercules) so I thought it was fitting.

All stock parts are reused and no extra parts are needed for assembly, except for six 20 mm M3 socket heads and a small piece of PTFE tube for the guide. Optionally, you can use standard size M3 heated inserts (either 4.5 mm length or 5.7 mm) and socket heads for attaching the PTFE guide but most will be fine with just using longer socket heads into the main casing, there is about 13 mm of material to screw into. But it's a hybrid so both threaded or heated inserts can be used.

If you download the individual 3MF files in the files section, they are design files only and can be easily printed on any printer / slicer. If you get a warning that they do not come from Bambu Lab just ignore the warning, they were exported directly from my design software.

Leave feedback in the comments. Thanks!

Recommended Add-ons

Also, there are a few community add-ons:

• Kraken AMS spool remake with TPU outer rim (By RifRaf)

• Kraken AMS HT Desiccant Holder (By RifRaf)

BOM - Bill of Materials

I recommend printing Kraken - Revolutionary Bambu Lab AMS HT in ABS, ASA or higher due to the high temp heater. Around 300 g of filament is required at the recommended print settings. 

I've printed most of the test builds in Prusament ASA and eSUN ABS, both brands and filament types work great.

Filament

• eSUN ABS

Fasteners

You need just six M3 socket head bolts, 25 mm in length is ideal.

If you don't have any at home it's best to grab the kit below, it will have everything you need for this build and more:

• 150 pcs M3 Hex Socket Head Kit

Optional

Although not required these PEO/PEI/PEY bed sheets are great, I have most options myself, it gives a quite cool look on the first layer. There are a few shops offering different plates:

• Build Plate PEO/PEI/PEY Spring Steel Sheet

The Hex Tools are superb for any 3D printer, I've had a few different ones over the years, these are the ones I use now as they are quite compact with replaceable different hex bits, they're the ones you see in the assembly guide a few pages down: 

• Hex Tools (1.5 mm - 3.0 mm) 

Before Printing Kraken

Make sure you dial in flow correctly before you start, we've seen a few Kraken prints that were overextruded so avoid that. Printed correctly, everything works just as stock but support for larger spools (among other advantages).

The Bambu Lab printers usually do a pretty good with automatic flow calibration but it's best to confirm flow anyway, sometimes it is inaccurate.

Print Settings

As it's a HT heater supporting up to 85 C heating, Kraken must be printed in ABS/ASA or higher. At the recommended print settings, around 300 g of filament is used in total including supports so you may like to step up to PC-CF or PA-CF even, as the filament cost will be low regardless.

Print the parts in the direction I have set them. I recommend using a wide brim for improved bed adhesion and Nano Polymer if you have some. 

Kraken prints in 15 parts and only very few supports are required (less than 10g in total) as the floor prints separately, it's pressed in place by the heater against a ledge of the main part for a flush floor and heater installation. The "cover" is a perfect fit gear housing for the feeder gear. 

The PTFE guide is actually two parts pre-assembled and it has a ball joint with a limited movement of 20 degrees. The "seal divider" is a press-fit divider to keep the rubber seal in place, it has small wedge shaped teeth that go into the main casing for alignment. 

The rubber seal is just peeled off from the stock casing and moved over, no new glue is needed but if you feel it isn't quite sticking you can reapply some new of course.

• kraken-ams-ht-cover-1.00.3mf

• kraken-ams-ht-floor-1.00.3mf

• kraken-ams-ht-front-roller-sleeve-1.00.3mf

• kraken-ams-ht-main-1.00.3mf

• kraken-ams-ht-ptfe-guide-at-spool-1.00.3mf

• kraken-ams-ht-ptfe-guide-main-1.00.3mf

• kraken-ams-ht-seal-divider-front-1.00.3mf

• kraken-ams-ht-seal-divider-rear-1.00.3mf

• kraken-ams-ht-spool-column-left-1.00.3mf

• kraken-ams-ht-spool-column-left-1.00.3mf

• kraken-ams-ht-spool-column-right-1.00.3mf

• kraken-ams-ht-spool-gear-print-4pcs-1.00b.3mf

• kraken-ams-ht-spool-gear-top-print-4pcs-1.00.3mf

• kraken-spool-ring-55-mm-1.00.3mf

The Kraken spool gear is actually identical to the normal Kraken ones so you can use the spool holders both for Kraken AMS, Kraken AMS 2 Pro and Kraken AMS HT.

There is a Kraken adaptive spool holder I will link to below that you can try as well, many prefer it as you don't need to use different spool rings. But both options are available to suit your needs.

Once you have printed everything, make sure to remove all supports completely.

Warranty

Kraken does not void your warranty but be careful, especially with the electronics, use an antistatic wrist band. Also be extra careful removing the cables on the main board, most cables have a little locking tab you need to press before you can unplug them.

The rest of the disassembly and assembly is quite fast and easy.

Although the mod is completely reversible and you can't tell the parts have been installed in Kraken, I take no responsibility and you're on your own. Be careful and take it slow, read this page twice before you start. 

Assembly Instructions

Remove the Bambu Lab AMS HT internals from the standard AMS HT box, follow this guide, it's not difficult:

https://wiki.bambulab.com/en/ams-ht/maintenance/disassembly-and-assembly

Once that is done, also remove the the gasket on the stock AMS HT, just pull it straight up and off, it's glued but pulls off easily. Leave the gasket with the glue side up so you can reuse it in the assembly steps later (without applying new glue).

Once done, you should have all the parts as pictured below:

Floor

Start by placing the main part (in white here) flat to a surface. Install the floor (in orange here) in this direction, it presses in place against the ledge and is then locked in place using the actual heater.

Tilt it as in the picture below and it should install easily. Take notice of the direction of the floor.

Do NOT install the heater yet, please follow the guide completely.

Filament Retraction Assembly

Use the two small screws (M3×5) and a hex tool. They're the shorter and thicker screws that have a wider head, acting sort of like a washer.

Make sure the housing is completely free of supports so the motor sits flat when you tighten.

Fully tighten it and make sure it sits flat.

Place the retraction gear in this direction, take notice of the foldable gear location and ensure the black plastic “washers” are in place and correct.

Just press in the gear set and you're done.

When the filament is retracted, the motor activates to both fold down the gear (it hits a printed limiter as pictured) and also to drive the final gear, which in turn rotate the filament spool.

Important! It's tempting to install the heater now but to make space for everything you must install the cover (orange here) for the gear set first as it partially sits below the heater.

There is a little alignment tab here, make sure you get it in the slot while pressing the cover in place.

Install the cover using two (BT2×5) screws. 

The heater will sit above a portion of the retraction gear cover pictured here, it's why it must be installed after the cover. :)

Now if you flip it over you should see the retraction gear placed neatly inside the Kraken.

Heater

Once the floor, retraction assembly gear cover are installed, continue with the heater. You need the heater and the four stock screws (BT2×6), they're the screws with a little wider flat top.

The heater installs in this direction.

Get the heater below this tab in the rear first when folding it down.

Then press down the heater against the floor and tighten the four screws as the same time. 

Careful to not overtighten as you could rip off the columns holding the heater! 

Heater in place.

RFID Coil

The RFID Coil sits in a plastic casing. It installs in a slot and is secured with a single screw in the middle. (BT2×5)

Feeder Hall Sensor Assembly

This is a small assembly with a hall sensor, detecting the filament. It installs using two screws. (BT2×5)

Begin by guide the cable through the slot.

Then install the two small screws, securing the assembly in place. By the way, the grey plastic casing you see here is what you press on through the rubber button on the rear of the AMS HT to release the PTFE tube going to your printer.

Feeder Unit

The feeder unit attaches to the main body using four (M2.5×8) stock screws.

First, guide the feeder unit's ceramic filament entry through the round cutout (bottom of this picture) then tilt it back and you can install the four screws.

Proceed to tighten all four screws as pictured.

Rubber Gasket

This little rubber gasket is to provide a seal between the AMS internals and the outside of the AMS HT box if you're running an external filament route. 

Just press it in the place in this cutout of the rear, you may need to pull on it a little and rotate it so it goes into the cutout slot. 

Install it from the inside out then just pull and rotate as pictured below.

Lid Status Hall Sensor

This sensor detects when the lid is open/closed and it installs by a combination of press fit and a locking tab.

Just slide it in and this little tab (circled) will lock it in place.

Main Board and Cables

The main board installs using three stock screws. I recommend you connect all the cables before you screw the board to the main Kraken casing.

Begin with the cables from the motor, heater and lid sensor, guide them in the small slot between the heater and the gear cover (in orange here).

First, connect the cable from the filament retraction motor here:

Connect the cable from the lid sensor here:

Next up is the narrower cable from the Feeder Unit, it's from the odometer board on it. Connect it here:

Next up is the wider cable from the Feeder Unit, it's from its motor. 

Now you'll also notice it's difficult to get the cables to reach without lifting the board so now it's time to attach it to the to the main Kraken casing. But that's no problem as the rest of the cables can be plugged in with the board in place.

Screw the mainboard in place using three stock screws (BT2×5), locations marked in red. In this picture I have only fastened the top left but you get the idea.

Organize the cables you've connected so far behind this tab.

If you happened to remove the cable from the AMS HT screen during disassembly, connect it here:

Connect the first cable from the heater here, it's for the temp and humidity sensor:

Next up is the small 2-pin connector from the heater, it's the thermistor cable, it is keeping track of the heater's temperature. It connects here:

Now we connect the mainboard power here, it's the one with a larger socket (2-pin, thicker cable):

Connect the feeder hall sensor cable here:

Next to it, we connect the RFID coil, it's the thin twisted 2-pin cable:

The fan from the heater connect here:

Next up is connecting the two heater cables.

The polarity doesn't matter so connect either one to top or bottom.

Don't forget to slide over the insulation sleeves.

Next, guide the wide ribbon cable from the main board below the slot of the heater, along with the other thinner wires coming from the mainboard. 

Place the small cables on the bottom against the heater and the wide ribbon cable on top. Then tighten the small screw with the bracket.

Internal PTFE Tube

Almost done. Press in the internal PTFE tube between the feeder unit and outlet.

If you're installing a new tube due to wear of the old one, the length should be 260 mm.

Flip it over and confirm that the filament release button work as intended. You have to press it quite hard, it's normal and just as the stock operation. Picture below is from Hydra AMS HT but the fitment is identical.

Seal Divider

The purpose of the seal divider is to keep the lid gasket in place and so it stays centered between the Kraken printed parts and the actual AMS HT box. There are two diveders and they only fit one way, begin with the one for the front.

Align it in this position, with the small section that's a little thinner on the end with the filament entry.

Next, press down the seal divider evenly across all cutouts. The tabs are quite thin but if you break one it's no worry but if you happen to break too many it's best to print a new seal divider and install it during this step. Just be careful and you shouldn't break any tabs.

Do the same for the rear divider. Once it sits flush everywhere it's quite strong.

Spool Columns

Start with the thicker spool column, it's the one that has a round cutout and press it into the dovetail cutouts of the main Kraken body.

The thicker one goes on the left side.

The dovetails are intentionally very tight for a sturdy support of the spool. If it's too tight don't try to force it too much but instead sand the male dovetails (of the spool columns) slightly and try again.

Install the right hand side spool columns as well and it should look something like this:

Now depending on how tight your dovetails between the spool columns and the main part are you may or may not need to use any fasteners but I recommend adding a couple for each spool column. The length doesn't really matter but around 20 mm is fine.

Fully tighten all screws, the top of the socket head should just about sit flat with the spool holder columns.

PTFE Guide

Install the PTFE guide. I recommend using two M3 x 20 mm socket heads and a short piece of PTFE, around 100 mm long. Optionally, you can use heated inserts and a shorter (8 mm) socket head but it's a bit overkill, there's plenty of material for just using threaded.

Start by attaching the base using to M3 sockets:

The press in the PTFE tube and finally the PTFE guide at spool:

Install Kraken in the box

Now we're nearly there, just need to install the whole assembly in the box. I find it's best to rest the assembly on the edge while connecting everything but do what you find is easiest.

First, connect the the mainboard power cable here, circled in red, it's the 2-pin cable that's a little thicker.

After that, connect the the wide flat (14-pin) communication cable, circled in blue. This can be a bit more difficult to get installed so just take your time with it and identify the direction before you start.

Next, connect the cables from the power socket in the box, don't forget to slide over the insulation sleeves afterwards, like pictured.

The polarity doesn't matter so connect either one to top or bottom.

Connect the front screen cable here, circled in the red. Then guide the cable around the hook, circled in blue, to get it out of the way.

Now you can begin to slide down the Kraken assembly into the box, make sure all cables are out of the way then install the rear side (the one with the tabs circled in red below) first then drop down the front.

Make sure the tabs in the rear go below the casing of the AMS HT box. Also, be careful with the hall sensor assembly in the rear with the rubber gasket and ensure it clears.

You can then fold down the front as well, you may need just force it slightly back to clear the retraction gear cover.

Secure it with two stock screws from below (BT3×8). I have just one pictured in my hand here but you should use two screws.

Adjust the Kraken assembly until you see the columns lining up then install the screws.

Don't overtighten these! We don't want the columns snapping.

Install the external PTFE coming from/to your printer.

Press the release button to test it, it should release the PTFE tube. Then insert it again and pull on it, ensure it is locked in place.

Lid Gasket

Now you'll see some small gaps in the front and rear of the unit. This is completely intentional as Kraken was designed so it could be printed on smaller printers like the Bambu Lab X1/P1, not only larger printers. The gaps do not matter as they're sealed up in the next step (installing the lid gasket)

Install the lid gasket between the Kraken just outside the seal divider. You should not have to use any additional glue, the stock glue will hold it. 

Place the gasket evenly and do one corner at a time, then the middle of the gasket, pressing it down. Once you've done that, press the rest of the gasket straight down.

Then open and close the lid a few times and it should set nicely.

Modifying the front roller

This step is basically the same as modifying the front roller for the normal Kraken as well as Python so if you're familiar with those it will be a breeze.

For this step, I like to use a thin pin to remove the rubber sleeve, for example a 1.5 mm hex tool:

Remove the rubber sleeve from the passive side of the front roller, meaning the side without the gear.

It's very easy. Just insert a thin pin between the rubber and the plastic casing and rotate the pin all around it. I'm using a 1.5 mm hex tool, it takes less than 30 seconds to do one. Save the rubber sleeve in case you revert to stock later.

Next, press in the printed gear sleeve as pictured below.

Spool Holders

Just like Python, Kraken uses a geared spool holder system, rather than having the spools running on top of rubber and plastic rollers. This greatly increases reliability and you can use smaller spools and cardboard spools without worry.

To install, just press in the printed bearing (or 608ZZ/RS bearing, if you have some) on each side of the spool holder with the "peg" facing outward.

If you use the genuine 608 roller bearings, first press in the bearing then press in the plug, it snaps in place and secures on its own.

You can use either version.

Spool Rings

With Kraken that's very compact, it's especially important for the spools to sit flat in the spool holder columns so the large gear doesn't scrape the side. Since it's so compact, it's also important that the spools are centered on the holder so I recommend using the spool rings to have them perfectly centered (concentrically) on the holder.  They snap onto the spool holder top and bottom and can easily be removed when switching spools.

If the spool is not centered, it could scrape the bottom or the lid. Using the spool rings ensure it is in fact perfectly centered.

I recommend printing a bunch of spool rings for the spools you normally use, perhaps in different colours.

Bambu Lab uses the 55 mm spool ring and Prusament usually the 51 mm rings.

Using the Spool Holder

Measure the inner diameter of your spool. For example, Bambu Lab uses 55 mm inner diameter of the spools. Install the 55 mm spool ring to the top and bottom:

The spool ring should fit snugly over the top and bottom. If it doesn't, you can scale it a little without worry or increase the flow ratio.

Installing the spool on the holder

Install the spool and tighten the spool holder top, it should also have a matching spool ring.

Notice: Don't overtighten or you can deform the large gear and get rubbing.

Now to install the spool in Kraken HT, just place it in the spool holder columns and at the same time make sure you align the spool gear with the little roller gear.

All done! 

Now all that's left is to press in the modified front roller and install the spool holder and load the spool.

Confirm the lid closes and opens fine, you may need to press it down slightly harder than before as you've removed and install the lid gasket, it will settle once you've used it for a few times.

Tip: When loading a spool, stand up the filament guide so it enters the entry more easily.

More Pictures