BuildTak works good, if you can cope with it!

[theRenegade]

The headline is also the bottom line here. I saw many posts in the forum that tell what a problematic printing surface BuildTak is and many seem to fail in using this great printing surface. To be honest, I ruined two sheets until I got used to it, but from the first print, I saw how good that surface clamps my large and flat prints to the bed wich is even more important when filling the print area on such big printers like the N2. Up to now I only print PLA and ABS on my Raise, other materials may need additional/different treatment, but there are some posts in the forum about it.

The short story / some more exclamation marks:

- Let the print bed cool down before trying to get the print off the bed (simulate cool down if room temp is almost like bed temp)!

- Never use sharp tools to release the print, otherwise you can easily destroy the BuildTak surface!

- Never use Acetone or Isopropyl-Alcohol to clean it, BuildTak will loose it’s adhesion immediately!

- If your BuildTak looses adhesion (or your cleaned it with Isopropyl-Alcohol), recondition it!


With any printing surface you have to use a correct initial Z-Height (bed to nozzle distance when Z is homed), this assumed as basic requirement. Some PLA tends to swell more than others, maybe you have to adjust Z-Height according to the filament that is used (newer IdeaMaker versions let you do this by software). I have no need to adjust Z, since I use about 4 PLA brands that I know to work similar.

I print with raft. Having an absolute leveled bed with a printing area of 30x30cm is something I question at all (with standard desktop printer setup and printing accuracy down to 10 micron), mostly because I am too lazy to analyze and tune. I always was arguing against raft, but this was another printer and the raft was without islands using up so much useless time and wasting material. If you have a perfect leveled bed and want better bottom surface quality than what can be achieved with a raft, just switch to glass. I also use the R3D provided printing profiles and bed temps for PLA and ABS, did not find I had to change anything (except layer height, I like to print with 0.3mm).

About the cool down. I use the standard bed temp (40°C for example for PLA) and the room temp is around 30°C. After the print finished, it is essential to give the bed and the bottom of the printed object / raft a cool down of some degrees. If you live in an area where it is warmer than 30°C you could try freezer spray as some suggested in the forum or maybe put the print plate at a colder place for some time (I would not dare to use a very cold fridge when the glass plate is still hot!).

After the cool down you have to get under an edge of the print (raft). I bought a spatula wich is 0.1mm thick this is already very thin and tends to bend. I have to use both hands to work it below the raft. In the picture you can see it is already bend, I still use it with the remaining straight part of the blade, always reminded to use it with two hands and to be careful. BuildTak sells their own spatula, I do not know how this one works. Mine costs about 3 Euros, that allows me to bend some more for the price of the BuildTak spatula. At the time I have that small and not sharp spatula under the raft, I use another one wich is much thicker but also not sharp to get under the first spatula. And now here’s the trick: You have to let the BuildTak ‚breath‘ while going further with the bigger spatula. Just use some force to push the spatula forward until you need much more force, then stop. You can hear the print like it’s cracking and sounds like there is air getting under it. Give it a few seconds until it stops then continue pushing the spatula deeper. You can also lift the spatula a bit after having stopped (doing this while pushing forward scratches the BuildTak) giving the print a small lift like that.

Doing it like this allowed me to get off any print off without damaging the BuildTak surface.

Recently I went into ruining my 3rd piece of BT because of feeling the need to clean it with Isopropanol-Alcohol from some oil that dripped down after lubricating the bearings. I had a feeling before that this might be not good, but I did it and went to the BT forum only after to find a warning about it there. In such a case or if your BT has lost adhesion because of being worn off, you could try to recondition it with ABS-slurry wich is just some ABS solved in acetone. Of course your BT will not look nice after doing that and after printing you will see some color marks of the used material also (now feel free to clean it with Isopropyl-Alcohol ), but your prints will stay like being glued to the bed again.

[Charles]

Have you ever tried to lightly sand your buildtak to recondition it? I've read it a few times, but it does not appear to be an offiical method to recondition the surface.

[theRenegade]

No and I won't sand it ever. I try to preserve the BT surface and it looks like ABS slurry works great as a reconditioner. I have no long time experience yet but a no more adhesive BT has got back it's adhesion with it.

[venosa]

I have my N2+ for about a month. Loved the Buildtak, never had a problem. The trick as I see is to use a very thin spatula completely flat and parallel to the bed, then, after it entered few millimeters under the print I put the original Raise spatula (thick) under the thin spatula as a wedge.
Works beautifully.

[theRenegade]

I first did it the same (used the R3D spatula with the thin one). But this one is quite sharp and when pushing it forward not absolutely parallel to the bed it will scratch the BT surface. So for clumsy guys like me the dull spatulas are the better ones.

[2CNK]

"Scotty Peeler SP-2" Buy some and don't look back. Got mine from Amazon. Perfect for getting that first little edge up.

I found that for larger prints with the Raise3D PLA, a bed preheat (10+ mins) with bed at 60C and printing the raft at 215C gives better adhesion. There might be more to the story but so far those are my results. I am also printing in a cool room, so that might have something to do with it.

Never knew you could re-condition BuildTak; I'll check that out - thanks for the tip.

[theRenegade]

"Scotty Peeler SP-2" Buy some and don't look back. Got mine from Amazon. Perfect for getting that first little edge up

I think this is way to thick and sharp (for me), prefer to stay with my dull and much thinner spatula.

I found that for larger prints with the Raise3D PLA, a bed preheat (10+ mins) with bed at 60C and printing the raft at 215C gives better adhesion. There might be more to the story but so far those are my results. I am also printing in a cool room, so that might have something to do with it.

I dont' know what is large for you, the raft on the pic is 280x165mm and you can see how it sticks to the BT (the reconditioned one).

[2CNK]

"Large" without context is a bad measure, you're right. I just did a 200mm x 200mm print today I consider "large".

There may be more to the story (and I suspect being in a cool room is making a difference) but a handful of times I've done 200mm -ish on a side rafts with an unheated bed adhesion seems weaker than the times I bump it up to 60C and a 215C raft.

The Scotty Peeler is sharp, but I made sure the bottom was flat and free of burrs with a little emery paper. I use it pressed flat against the build surface so the edge doesn't catch on the BuildTak when moving. It's great for getting under and lifting an edge, but not for applying any levering force.

[Andy Cohen]

or...
You can flip the plate and use Aquanet unscented super extra hold at a cost of $2-$3 for a can which will last about as long as a sheet of buildtak and realize what a waste of time Buildtak was for you.

[theRenegade]

"Large" without context is a bad measure, you're right. I just did a 200mm x 200mm print today I consider "large".

There may be more to the story (and I suspect being in a cool room is making a difference) but a handful of times I've done 200mm -ish on a side rafts with an unheated bed adhesion seems weaker than the times I bump it up to 60C and a 215C raft.

You can calculate that a 280x165mm solid raft is larger than what you consider large and also you can see how it sticks. If I had use for a 280x280mm raft I'm sure I could show that it would stick too.

Next would be interesting what a cool room is considered by you. I can tell that what I have told works with room temps above 20°C.
I print 205°C with a 40°C bed temp, no preheat needed and that's just the complete story.

[theRenegade]

or...
You can flip the plate and use Aquanet unscented super extra hold at a cost of $2-$3 for a can which will last about as long as a sheet of buildtak and realize what a waste of time Buildtak was for you.

Why should I flip the plate, buy chemicals and switch to another treatment of the bed when all is working well with the standard printer setup? This I would consider a waste of time. I doubt you could show better sticking larger prints because how should this look? It's already perfect (see the pic in my earlier post).

[2CNK]

I'm also finding it easier to just work with what BuildTak likes, but it's nice to know flipping the plate over and using aquanet will work as a backup.


This is anecdotal but yesterday I did two identical prints on identical "ring" shaped rafts. 30mm wide raft, 210mm diameter. The first one I saw what I thought was over-extrusion on the rear side, but it turns out that the raft had lifted slightly at the back so the nozzle was pressing into the lifted area. I aborted the print. This was on a default 40C bed with 205C extrusion. The next print was identical but 60C bed with 15mins preheat and 215C for the raft. This one stuck, and from my subjective experience with removal after it cooled down, it was stuck quite well. The room is a pretty consistent 17-18C.

I'm finding it interesting and I record everything, but I'm often guilty of just sticking with what appears to work because there's so much to fiddle with on all other fronts.

[theRenegade]

This is anecdotal but yesterday I did two identical prints on identical "ring" shaped rafts. 30mm wide raft, 210mm diameter. [...]
the raft had lifted slightly at the back
[...]
The room is a pretty consistent 17-18C.

Such a raft should not lift at all with a regular setup (checked your initial Z-Height?). Your room is quite cold and if the preheat helps you should do it.

[Vicky@Raise3D]

In my opinion, bed temperature could be the main cause. Since the ambient temperature is cool, 40C is not enough. In most cases, preheating is unnecessary for PLA.

[theRenegade]

Right now I am not sure anymore what 2CNK meant with that pre-heat. I thought it was about heating the bed to 60° and then do the print with 40° bed temp. This I would prefer over using more heat on the bed for the complete print job.

But maybe I got this wrong. What I would not do is going too high with the bed temp for PLA (not beyond 50°), as I also would lower the extruder temp also (I print with 205° for most PLA).

Maybe 2CNK could try 45° bed temp next and raise to 50° if it is not enough.

[2CNK]

I haven't tried 50C or other temperatures in between, I don't remember why I originally tried 60C, I don't have that recorded for some reason.

I do have my results for 60C recorded, though. I preheat the bed to that temperature, then print at that temperature. I know PLA can deform under stress at temperatures as low as 60C, but rafts so far seem to adhere very well for me.

According to my notes, I have never had a raft lift when the bed has been heated to 60C - regardless of extruder temperature (which has varied from 190C to 215C). I have had raft lifting at 40C on several occasions.

Like I said, I haven't tried between 40C and 60C yet - I will see how that affects things.


Re: dropping the extruder temperature:
It has been my experience when printing rafts of larger than roughly 100mm on a side at 205C that my extruder cannot quite keep up when printing the solid layers of the raft. I have attached a photo as a typical example.

This is typical of raft printing at 205C - I get the occasional loud knock sound from the print head, which matches observed low extrusion like in the photo. It took a long time to find the source of that sound, but I narrowed it down to the extruder stepper. I have been told that represents the stepper skipping steps, very possibly from not being able to keep up with the extrusion rate. I can reproduce this behaviour on demand, all I need to do is print a raft of roughly the size in the picture or larger at 205C.

I have gotten away with lower extruder temperatures only when printing small rafts for small models (like a 2.5cm Marvin, 20x10mm box, or a Benchy Boat). For small models with fine detail I have printed them model itself as low as 195C with good results, it's just the heavy extrusion of the raft it won't keep up with.

I have so far addressed this by printing the raft at extruder temperature of 215C, then dropping my extruder temperature back down to 205C nominal for printing the object. I do this via the touchscreen interface, either tapping the bed temperature and setting it directly, or using the TUNE interface. My print results and bed adhesion are both good so far.

I might benefit from a higher nominal extruder temperature overall, instead of fiddling with different temperatures for the raft vs. the model, but I haven't tested further on this front yet. I only got my printer a couple weeks ago, so there's still a lot of question marks I haven't filled out.

[Andy Cohen]

or...
You can flip the plate and use Aquanet unscented super extra hold at a cost of $2-$3 for a can which will last about as long as a sheet of buildtak and realize what a waste of time Buildtak was for you.

Why should I flip the plate, buy chemicals and switch to another treatment of the bed when all is working well with the standard printer setup? This I would consider a waste of time. I doubt you could show better sticking larger prints because how should this look? It's already perfect (see the pic in my earlier post).

Fair question.
2 answers:
1. It is not perfect. You simply have not had a project yet which puts you into the use case scenarios where either you have to chisel a single layer off the crap or you have to destroy it to get the very large almost solid object off the plate.
2. The stuff is expensive to replace.
Also... you probably should NOT flip the plate, use Aquanet, then flip back and use the buildtak. BAD idea. If you go back to the expensive and far from perfect Buildtak you will need to remove all the aquanet or getting the plate off again will be a pain.
Once you take the time to actually learn to use Aquanet you will find that you can actually dial in the amount of stick you want. As such it can hold a HECKALOT more then Buildsmack can. Although unlike Buildwhak which you cannot actually control stick and release, with AQ you can put the super dialed in held object and the plate into a freezer for about 15 min and it simply lifts off the plate. No fuss, no chiseling, no need to buy a new overpriced sheet because you had to cut or scrape.
Note... this is ONLY Aquanet, unscented, super extra hold and NOT hairspray in general!!

However, I can understand that if you are still using the factory fixed bed which makes changing the bed position relative to the hotend a major PITA rather then using conventional bed leveling screws which makes it easy to do in real time. Then yeah I can see how you would think your setup is perfect. But IMO it isn't. Those of us who have a bunch of plates and swap them during production runs already know that plates vary in height and a fixed height approach is simply a no go.

[theRenegade]

Well, I think you probably missed the topic, there is no problem with BT, it works good if you can cope with it.

That's why there is no need to discuss switching the plate (that can be adjusted by IM Z offset if different in height, BTW) and different bed leveling screws and other things, it's just about the original bed with BT surface that works good, just if...

You also seem to have missed to read my initial post were I described my first failing steps with BT until I recognized how to treat it right. I also cannot follow your calculation that calls BT being expensive, you wrote that one can of AN equals one BT sheet, wich I will proof wrong with my current sheet of BT (I will be back on that).

The message simply is: If BT is treated right there will be no issues like the ones that so many guys warned of in this forum. If you have the need for other plates and surfaces, switch them. If you want to mod your printer, mod it. But I can see no issue with using BT until you show me a larger flat print than I showed wich cannot be hold on BT and not removed from it.

[theRenegade]

Update: Currently I print a 10KG spool. Without having an accurate measure I think I'm done with 7KG of that spool already.
I lubricated the printer between two prints and again did not take care of the dripping oil wich made cleaning the bed necessary.

I have enclosed pics of the BT surface before cleaning wich shows much traces of the prints I did before and another pic after cleaning the BT surface with Isopropanol and Acetone (don't do this if you BT is still o.k.!). After cleaning I reconditioned it with ABS slurry.

It's the same BT sheet I used at the start of the post and it was usd for nearly 10 KG filament with prints being more flat than high and the raft always in the same areas.

I think it's ready for the next 10KG now...

[2CNK]

Do you have any guidance on the specifics of ABS slurry reconditioning? i.e. what proportion of ABS to acetone, how much to apply, etc? Does it matter much?

I did a quick google search on reconditioning buildtak but didn't get any hits. Seems like a good thing to know.