I ordered my first TPU print and I am fairly happy with the end result. But I would need the end result to be with even better quality. Might somebody know what is the best printer or best Hub to get the best quality by printing TPU?

BR, Antti

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Hi, Can you upload a picture of the print that you already have. Then I can evaluate, if I would archive better quality prints. -Marius

Hi, attached are the prints.

The blue design is printed with 85A and gray with 90A.

BR, Antti
TPU print.png

Hi Antti,

i could offer to print those parts in Ninjaflex (85A). I only print in snow-white Ninjaflex but if you order larger prints i’d buy other filament colors.

What exactly do you wish to improove in the print?

I’d be able to print this with better surface quality, take a look at my hub if you are interested.

https://www.3dhubs.com/siegen/hubs/marius

Are there specific features, that this print has to have like solid infill and what is the size of this print ? I’d assume roughly 5cm in length but there is no reference in the picture.

-Marius

Hi,

Yea to print with the better surface quality is exactly what I am looking for.

You assumed the size right it is about 5x5cm wide. There really is not any that specific features, but the print would need to be with more even surface.

Hey what is the difference between ninjaflex and TPU because I dont really know?

-Antti

Hi Antti,

there is no real difference between TPU (thermoplastic polyurethane) and Ninjaflex. Ninjaflex is just the most common brand for elastic filament and prooves to produce very high quality material. Ninjaflex is (on the chemical point of view) the absolutely same material, however the purity of the material aswell as the consistend diameter of the filament make Ninjaflex one of the best choises for flexible parts.

Cheaper brands may have impurities in the filament that can cause a rough surface aswell as an overall weaker print, more on that later.

You can have a look at technical properties aswell as the safety data sheet when clicking this link:

The filament prooved to have very much surface friction aswell as “adjustable” flexibility depending on the infill.

If you go for low infill density like 20% the filament the parts will be very bendable, however they are not as durable as solid parts. The elongation before breaking is about 400% so you can expect very much flexiblity from this material.

However due to the method of printing layers, that most printers (aswell as mine) use you should expect the part to break at 250-300% elongation depending on the direction you are pulling and the infill. The parts tend to be weaker when trying to pull layers apart compared to attempting to break along the printing direction.

However i have not yet archieved it, to break a 1mm thick disc (size of normal CD) just by pulling on it with bare hands, no matter what direction and angle i pull from. Just with pliers and a little bit of cutting i was able to break it in two halfs.

I hope this helps you to decide if Ninjaflex is the right material for your application.

At the moment i have no pending order and could start printing immediately.

-Marius

Hi

Are you in a hurry to get the print? I can definately get a better print. Out of ninjaflex but will get some soon. How flexible should the parts be?

Hi Marius,

I am at the moment waiting for one print from TPU. When I receive it I will have to value what would be the best material to continue. Thanks a lot for your info.

BR, Antti

Do you also have NinjaFlex semiflex?

-Antti

Hi,

I would need my next print by the end of the next week. I am actually waiting for my TPU print to come so that I can make some changes. I am actually just trying to figure out how flexible the parts should be. I am thinking that they might have to be NinjaFlex Semiflex density. Are you able to print Ninjaflex Semiflex with 100% fill density?

-Antti

Semiflex is what I would use to get flexible but tear resistant print. Yes I can print it with 100% infill. Problem is that I don’t have it atm. Need to order some this week since I need it anyway.

Not yet, but I already coincidered buying it, I’d get my hands on it if you need to have this filament. However please understand, that I’d have to have the order confirmation before buying the filament. It’s quite expensive and there is low demand on such elastic plastic so I need to know, that it get something more off of it. The price would be the same as for ninjaflex. However you could choose the color of the filament when I buy it for this order. May I ask you, what purpose the parts that you showed me should fulfill, I might be able to get the properties that you want from semiflex by changing the settings of ninjaflex-prints. -Marius

Hi Antti,

since your most important goal is to get best surface quality i thought it might be good to show the quality, that i was able to archieve with my printer on settings that i would also use for Ninjaflex.

The picture shows a kind of lego brick made out of yellow PLA, i have broken off the knobs on the top surface because i experimented with layerbonding.

Hope to hear from you soon,

Marius

I am first trying the find the right flexibility with TPU. If I am not able to find it I will try to find it from Ninjaflex.

Hi Antti, If you need more durable and less flexible material for the print you might be interested in the following: Because I have a dual extrusion printer, I can print ninjaflex and ABS in one part. With that you can modify the part so that certain parts of the print are less flexible or even stiff. I could modify the model to your preferences. If you are interested in this please tell me. If you could tell me for what the print should be used I could help you find the correct material, if you need just some flexibility nylon would be a concideration. Nylon is very durable and bendable. Beside all that I think it would help, if you clarify what you mean with flexibility, do you want to elongate and stretch the part or should it be just bendable? -Marius

@anttitolvanen if you want flexible but better looking you might want to consider nylon - Taulman PCTPE is flexible, really tough, gives a really good surface finish and can be printed by most printers (whereas ninjaflex and filaflex are fairly tricky for bowden and have less good surface finish) The other advantage is you can easily die the finished print and so have any colour you want!

Or you can print the model in PLA and mould from it and then cast any silicone shore hardness you need.

James

Hi James,

I have actually tried nylon before but not with PCTPE. I might try that If I cant find the right material from TPU or from Ninjaflex. Thanks for the tip.

-Antti

Hi Marius,

I have tried ABS and nylon before, but I think that TPU or Ninjaflex are the right material. I just need to find the right hardness.

The print is going need to be suitable to use in a bottom of a sport shoe.

Hi Antti, I thought about a hybrid print made with ninjaflex and abs. I could print the outside and the flat part that connects the spikes out of ninjaflex. The core of the spikes would be made out of solid abs, to give stability. I could also print some layers of the flat surface out of abs, something like every 5th layer. With that I could easily adjust the flexibility. If you want some test parts I’d print them for one third of the normal price that I take per cm^3. You could order a 30x30x2mm cubiod and I print three different versions with a different ninjaflex-to-abs ratio. Then I’d send them to you so that you get a feeling for both materials and the amount of flexibility required. I checked the shipment cost, which is fairly cheap, just 1,45€. -Marius

Hi,

I really appreciate your effort, but I want to keep it as simple as possible, because I might want to print several other prints as well with the same material. The more I am searching for the ninjaflex semiflex material the more I am actually liking that. I really want to have a print with that material at the moment. Big thanks to you for giving me info from ninjaflex.

BR, Antti