Blob Shield

[MegaloDon]

I'm not sure if the way that the Cube Print software causes blobbing is unique to the Cube Print software or if anyone else has come up with a similar solution. Even though I am calling it a blob shield, it technically isn't shielding anything.

When the software generates a print file for the left extruder, it does retraction on the left side of every layer, and vice-versa for the right side. Retraction (pulling the filament back a bit so it doesn't ooze out and cause stringing) is normally only needed when the print head is stopping on one part and moving through a non-printed area then it undoes the retraction (pushing the filament back to the tip so it doesn't leave a gap) before printing again.

Unfortunately, Cube Print software tends to put retraction on every layer even if you are printing a simple cylinder for example. The problem with that is that the retraction causes a slight pause to retract, then undoes the retraction and continues printing in almost the exact same spot. I have tried modifying the .bfb code to remove retraction entirely, but that can be very tedious and if it is too small of an object, it doesn't have time to cool between layers and will warp or twist.

The best solution I have found so far (besides using better software) is to create a blob shield. The idea is to create another object next to the main object. As an example, if you print a cylinder, when it gets to the end of the circle it will perform retraction and then move to the other object and undo retraction before printing again. This eliminates that pause and then continue in almost the same spot. You will still get a slight line, but not the blob of plastic that the pause causes. Also if you create the shield .2 mm taller (assuming you are printing at 200 microns) than the main object it will eliminate or reduce the blob you get on the top at the end of the print.

You could make a thin cylinder around the entire object, but it is only needed on the side of the extruder being used.

BlobShieldExample1.JPG

A cylinder all the way around would cover either side so it doesn't hurt.

BlobShieldExample2.JPG

Also a cylinder is not necessary. A simple flat wall would do as well.

The reason why the print head I designed http://www.print3dforum.com/showthre...ll=1#post42476 needs to have the rounded side away from the extruder is that even with the blob shield, you will still get a slight line. It will still work with that line but this way it is a nice clean print.

To show what I am talking about I included the BFB file for a small cylinder here >>> https://drive.google.com/open?id=0B6K745kRy16-dUtLTXE0TFdjQ0k

Cylinder.JPG

This was sliced with Cube Print software and converted to BFB with Mythandar's tool.
It has 41 layers and 87 retractions.
The comments at the top (starting with ^) have the details of the object.
The code for retraction is M103 so if you use a good text editor like Notepad++ you can count them.

[TommyDee]

I found that enclosing the object inside the shield can cause object overheating issues.
I tend to print something... anything at one of the corners, forcing the print out from under the hot head.

The only software I know that changes this "blob" aspect is 3D Builder. And only for ABS. Night and day!
And that slicer too is from 3DS. An early version perhaps.
But I still contend that 3DS added the blob so it wouldn't rival the Cube|Pro

Why no one wants to chase that nit just boggles my mind.
If it was within my capabilities, I would be all over it!

[MegaloDon]

I found that enclosing the object inside the shield can cause object overheating issues.

I have not experienced this yet. What issues does it cause?

I tend to print something... anything at one of the corners, forcing the print out from under the hot head.

I don't understand how that would help. The object has to be under the print head to print it.

Why no one wants to chase that nit just boggles my mind.

If it was within my capabilities, I would be all over it!

If you are referring to reverse engineering Cube Print software and rewriting it, that is a MAJOR undertaking. I can understand why noone wants to do it. Especially since Mythandar has provided ways to use 3rd party slicers to do the same thing.

I am simply trying to provide an easy way to fix issues for people who don't want to use 3rd party slicers.

[TommyDee]

...doesn't even warrant a response

[Mythandar]

I had looked through the cubify program to see what could be modified. Unfortunately, they have all the important files encrypted. I spent a little bit of time trying to get into them but it's beyond my ability. That's when I decided to make my modify program.

[TommyDee]

You've suppressed a conversation to deal with a big problem that can be found and fixed easily.
You've already said you cannot do whatever it is you think I was talking about.
So why would I again elaborate to you?

And as for the hub... I had this done for fun over a weekend but left you alone to do yours... with the manual feed.
Why do you think I knew what you could use for anti-rotation? Seriously, I do keep up!
When your novel concept evaporated into a .cube3 file, you didn't simplify what I had. So why not?
It was properly vetted behind closed doors, yes. I need to know the variation is functioning.
That is simply good engineering as you well know!

You dropped the manual feed and I released a hub that had everything else already.
People have a choice. You had a choice. Big deal. Its covered. I didn't just do it for here or Thingiverse.

So no, there is an answer before you, but you refuse to see it. I cannot lead the blind.

- - - - - - - - - -

Mythandar, this keeps getting overthought and squashed before it can ever be brought to the light of day.

[Mythandar]

Figuring this out was a good catch don. I bet it still kinda does this in the other slicers, but I always had it randomize where it started the next layer so it would have been spread out and never build up in one spot. Which is what I assume was happening.

We didn't have much luck getting good prints from cura, but since version 2.4 (i think it was) they added bfb support back in. I wonder if it'll print better than the 15.x version we had to use back when I made the guide.

[TommyDee]

Really, Don, I am not an idiot and I am very tired of you steering my replies like I am one.
The hostility is yours. I've tried my damnedest to come in with a gentle reminder when you ask for help.
And I get nailed with very stupid divisive deflections disguised as "interpretations" which is very insulting since every idiot would know better.
Not once, but -every- -single- -time-. You ignore the point and thereby you deflect what can be a good discussion. Why? If you have nothing to add, don't.
I do have something to add. My comments were directly related. Happy to clarify if you don't treat me like an idiot.
You, Don, treat me like I'm an idiot and you don't deserve replies. You should try adding value instead of stifling it.

Oh, and for everyone else's information, Don is right. But at this rate, I will never be able to add what really helps.

[bolsoncerrado]

OK guys keep it easy and cordial for everyone to take benefit, please! Once again, we're a very small family on our own so we better stay togheter!!

Everyone is welcome to share their own knowledge, methods, tricks and tips for everyone else to read and decide on which route is best for each case!

Just keep it civil please! It saddens me a lot to see you fighting each other. :'(

[Pink]

print fouten 2 bew.jpgprint fouten 1 bew.jpg
Look at the arows, this is what I mean. It's not only on the outside of the part but on the inside two. What can I do about it?

Greetz

Pink