RE: Printing TPU on the MK4
I'm not an expert by any means, but I've managed to make things work. Temp and mvs are BIG factors. I've also found that retraction length and speed is important the software you get. The stock ninjalfex profile for instance, sets the retraction speed to 60ms! this plus a long retraction length = jams for me. I lower the retraction speed to 20ms and only 1.5ms. it also fixes some annoying under extrusion I see with ninjaflex.
This under extrusion. The xyz cube showing the fix with reduced retraction length and speed. For ninjaflex I take the MVS down to like 1.2. Slow I know, but again reliability and no jams is the important thing to me. I don't sell anything I make, I'm too much of a perfectionist. I did make a bunch of these colorado coasters though and gave them away to nice folks we met on the cruise we just got back from. I mostly just make stuff for friends and family.
RE: Printing TPU on the MK4
I've only asked for cost on some of the things I've done for others, just so I'm not burned by expenses. Haven't really sold anything. In my opinion the seams really aren't good looking, and I'd have trouble explaining why they were so unattractive.
I'm looking at GT-3 TPU by Sainsmart which claims to be able to print faster. It's the same price as normal TPU so not a disaster if it doesn't live up to its claims. Might pick up a roll to see if I can print a little faster.
RE: Printing TPU on the MK4
yeah I'll agree about the seams, but again, I'm not at all an expert and I'm sure there's room to improve. however you'll never completely get rid of seams. it comes down to what the model is and how soft you need it to be. there's zero way you're going to be printing fast with 75A shore hardness tpu lol Ninjatek makes something called Cheetah that's meant to be printed "fast" and when we say fast here that's relative to the 10-15ms that'd you'd print regular tpu. I use ninjaflex(85A) a good bit to make things like keychains etc. I've not gotten beyond an xyz calibration cube with the chinchilla(75A). I've been experimenting with petg + tpu to have stiff things that have a flexible edge and that works pretty well. with the XL I've also been playing with tpu + PLA supports with an interface of some soluble material like BVOH. though with tpu you can use pla as the interface material too. being able to print supports that can be detached from your tpu prints really expands the possibilities of what you can print in tpu. When I'm back in my routine I might fiddle with improving the seems a bit on tpu.
RE: Printing TPU on the MK4
I think what's best is to pick a couple brands of tpu. My two are ninjatek and sainsmart, and slowly iterate on those trying to tune until you get the result you want. This allows you to dial things in. I say this particularly if you want to sell your end result. Unlike rigid filaments where you can mostly mix and match without a ton of tuning, each variety of filament(vendor + softness) requires you to basically do the whole tuning thing again which is why I hate printing with it most of the time.
RE: Printing TPU on the MK4
others can chime in here, but I think the ugly seems could be related to retraction. I experiment with it later this week.
RE: Printing TPU on the MK4
Don't like to sound like a Luddite, but how do you attach pictures here? Wanted to show the difference of a couple of samples.
NonIS has a less prominent Arachne aligned seam than IS. An IS Arachne random seam looks like acne with pimples protruding from the surface. I am trying out a Classic random seam, and so far it looks far superior. The pits are negative rather than positive, and are smaller. I think it looks superior, but the print hasn't completed. So far, non IS printing, even at full MVS looks a whole lot better than IS at 80% MVS.
RE: Printing TPU on the MK4
You have to go to "Add Media" Now here's the rub. if you have an iphone(like me) it saves pictures as .heic files and those can't be uploaded directly. On windows I have to open them with picture viewer and save as a .png(or .jpg) and then you can upload them. it's annoying.
I know what you mean about the seams. They do seem to be worse now than they used to be. I hadn't associated that with arachne but it could be. I'll be interested to see your pictures.
Don't like to sound like a Luddite, but how do you attach pictures here? Wanted to show the difference of a couple of samples.
NonIS has a less prominent Arachne aligned seam than IS. An IS Arachne random seam looks like acne with pimples protruding from the surface. I am trying out a Classic random seam, and so far it looks far superior. The pits are negative rather than positive, and are smaller. I think it looks superior, but the print hasn't completed. So far, non IS printing, even at full MVS looks a whole lot better than IS at 80% MVS.
RE: Printing TPU on the MK4
One more try on the pictures...
Trying a gallery. Why do they have to make this so difficult? First is Arachne non IS aligned on top of IS aligned. Second is Arachne IS speed with random seams.
RE: Printing TPU on the MK4
No Joy
RE: Printing TPU on the MK4
No gallery was attached. Jeepers. How convoluted.
RE: Printing TPU on the MK4
so in the bottom picture on the left, what setting is that?
RE: Printing TPU on the MK4
Quality, (not IS) no change in MVS(5mm3/s), retraction=20mm/s, T=218C, Classic Perimeter Generator: Random seam. Thick bridges. Fill gaps.
RE: Printing TPU on the MK4
definitely looks better than the arachne ones. I almost wonder if you reduced the retraction length slightly if you could make those seams smaller. and go 216C
RE: Printing TPU on the MK4
your arachne seams look worse than mine for some reason
RE: Printing TPU on the MK4
So like Retraction length = 1mm, rather than 1.5mm? Or 1.25mm?
I could see going slightly cooler, right now I have first layer 220, then 218. I can try 218/216. My overhang on the top of the new print is drooping at 218, but it is a span of 8mm.
RE: Printing TPU on the MK4
your arachne seams look worse than mine for some reason
My MK3S+ had better looking aligned seams than the MK4 using Arachne.
RE: Printing TPU on the MK4
yeah something like 1mm. yes that span is quite large for tpu. a lower temp would help with the droop
RE: Printing TPU on the MK4
yeah I would agree with that. Both my MK4s were previously MK3S+ that I upgraded
your arachne seams look worse than mine for some reason
My MK3S+ had better looking aligned seams than the MK4 using Arachne.
RE: Printing TPU on the MK4
216C printed a little worse than 218C. Think I will stay with 218 and classic random perimeters. The 1mm retraction wasn't that good either. Think the 1.5 was a little better. Might try 1.25 or so. There were bigger strings in this part, rather than just wispies the time before.
Going to try the big part tomorrow. Need to be around while it is printing - don't want to leave it unattended.
RE: Printing TPU on the MK4
it could be 216 works better for me because I print in an enclosure. But that's good info. I think I might try to print just a standard cylinder with some infill. I don't think the large bridging areas are necessary for this test.
216C printed a little worse than 218C. Think I will stay with 218 and classic random perimeters. The 1mm retraction wasn't that good either. Think the 1.5 was a little better. Might try 1.25 or so. There were bigger strings in this part, rather than just wispies the time before.
Going to try the big part tomorrow. Need to be around while it is printing - don't want to leave it unattended.