Frame modification  

Re: Frame modification

Paolo

Of course that mod would work; it may even allow you to have the heated bed spring-loaded on the chassis.

However, IMVHO by making the mod, you would not be solving the root cause of the problem and simply addressing its symptoms.

It is an aluminium frame and can easily be cut by hand with a junior hacksaw, but any actions you do take has to be your decision.

I can understand your frustration; it took me a few weeks to work out the problem and I am still not sure what I did to correct it. All I know is that I was patient and something (non-destructive) that I did made the problem go away.

Now I have a bed that is level to well within 0.1mm which I very rarely have to calibrate (only following a glass clean).

I still have other issues (like the Z endstop being quite imprecise at times), but I do prefer simpler and less invasive solutions where possible.

Peter

Re: Frame modification

Instead of chopping pieces off the frame, why not use something like this...

http://www.thingiverse.com/thing:1530686

Re: Frame modification

@Peter,
You're right! I do not want to make invasive changes and it is better to preserve the "toy" like Mom did it :lol:.
Also, at the moment i do not meet particular problems (elastic bends do their job) but i have to learn on everything about 3D Printing.

@Richard,
That's seems very good and i will try a shot.

Thank you for the support,
ciao

Re: Frame modification

@Peter and Paolo

Good to see the debate and proposed solution to what is, ( Peter), a genuine issue for some. Peter you had to add extra packing to solve your bed levelling issues, with blue tape. Prusa Research I suggest needs to look at this issue and make a simple solution for all.

I am lucky, my glass is pretty level. I did not have to pack with blue tape under the bed. I admit my bed seats well now. I push it down gently after reaching bed temp. It however can still move.

Re: Frame modification

Nigel

In an attempt to put your misconception to bed (as you do appear to be rather transfixed by my "blue tape fix") I will explain why I have done this.

For the vast majority of my prints, I use KISSlicer to slice the models. I find that I get the best results when using this slicer; for me it is an extremely good slicer and it is very flexible. It does, however have one drawback, which I have used to my advantage and that is it is not possible to define the thickness of the first layer.

It is possible to do this using the "Bed Roughness" parameter, but this would need to be set every time I wished to print at a different layer height.

Now the Prusa "original" requires a first layer height of at least 0.23mm. As I don't have direct access to Josef and his team, I am unaware of all the reasons for this, but I would guess that one of those reasons would be to address the manufacturing tolerances of both the glass sheet and the PCB heater.

On every firmware release, I re-compile the firmware, setting the minimum Z value to zero. This allows me to print every layer, including the first, at the same height, thereby avoiding any changes to (or rather me having to remember to change) the "Bed Roughness" parameter within Kisslicer.

When printing at less than 0.15mm layer height, I found that the bed was not sufficiently level to lay down a decent first layer, so I experimented a bit and found that the blue tape gave me bed sufficiently level to print a 50 micron first layer.

Had I remained with the original firmware, then blue tape would not be required, but as you probably know, this is an "Open Source" printer with "Open Source" software driving it, and therefore nobody should have a problem with what I have done.

Once again, I would state that the "Blue Tape Fix" that I have implemented is solely because I have chosen to deviate from the standard printer hardware and firmware supplied by Prusa Research.

I hope that you are able to follow my reasoning here and that you will now stop throwing that one at me!

Peter

Re: Frame modification

Peter,

I thank you for your patience. The extra padding with blue tape I do not need. I guess I am lucky or know what is needed really. With a genuine Prusa I3 with no firmware mods. I get perfect prints with the genuine I3 as specified. the 50uMM prints are fantastic.

Re: Frame modification

Peter,

Maybe you should go back, and try the current firmware and settings out of the box with your so called Genuine Prusa I3 printer. Everything is fine here. I get the best prints out of the box with no changes needed. Once I levelled the build plate reliably.

I have gone over to buildtak as an experiment. Simple Z height adjustment needed (mechanical) . Seems to work well. I will be experimenting with other surfaces.

Yes the genuine Prusa I3 is an open source printer. But I thought here, this site, we are talking about the genuine article, not a mod or clone. My genuine Prusa I3 is running now, as specified. No mods. I sorted my bed levelling issues and use the stock solution.

Re: Frame modification

Peter,

You can define the first layer height in Cura which I use under Repetier Host for my Fabrikator Mini
Even Slic3r provided by Joseph Prusa allows first layer height adjustment. You are talking bollocks.
KissSlicer you use, needs dumping. It hasn't been updated since 2014.

Sorry. I may have stepped over the line. Your solution as you defined is valid and I accept that. Another solution you could try is Simplify3d. I use it on my other 3D printers (all different) it gives me great results. I am preparing a suitable profile set for the genuine Prusa I3. This software is the bees knees. You can define each layer as you like.

I use the free software only with my Genuine Prusa I3, as provided on Jospeh Prusa's site. It gives me perfect prints. Simplify3d is good, I use it on my other printers.

Re: Frame modification

Nigel

Sorry, but once again you have shown just how wrong you are (yes I know, I tried to keep my promise but sometimes I really cannot agree with you)

Kisslicer was last updated 5 days ago.

Peter

Re: Frame modification

Peter

While I try to refrain from getting in these little squabbles, I can see where Nigel is coming from on his statement about Kisslicer. On their website it lists September of 2014 for the latest release. If there is another location one should be looking for releases it would be nice to know.

Re: Frame modification

Checkout the forums: http://www.kisslicertalk.com/

Releases: https://www.dropbox.com/sh/3evahzu5gfelpte/AABau30kpAP2BEY1tffRFeGZa?dl=0

Bye

Re: Frame modification

Peter

Many thanks for the links. I can say I never would have even thought to go to their forums to look for releases.

Richard

Re: Frame modification

But why? use Kiisslicer when Joseph Prusas Slic3r settings as provdied are better and gives wonderful prints. With other slicers you maybe set free. Simplify3D is a commercial program that has paid me back in dividends, many times over. ie perfect prints. It has profiles for many 3D printers.

I have used a jospeh Prusa profile within Simplify3D for 1.75 mm PLA. I am creating others for differrent materials I owm. Other times I use Jospeh Prusa's I3 settings mostly and for other printing materials. Specified in the profiles.

Peter, You seem a slave to an inferior slicer.

Re: Frame modification

@PJR

Thanks for the link, as many I didn't know there was another source for latest version, I was stick to 1.4.5 for now.

@Nigel

The answer is probably "Why not ?". I'm not sure qualifying KISSslicer as inferior makes sense. Most of slicers I tried now have different phylosophy, and you have to understand it to take advantage of it. For now if you have a better understanding of the way to control Slic3r, like I do, that does not make it superior, that just makes it adapted. There are specific areas (initial bridging layer and partial layering on top of infill) where I found difference in behavior, but it's not the thread to go deeper into this.

Regarding the OC of the thread, I do not think modifying the frame is a good idea, it will add unwanted flexibility, and is mostly a workaround to an issue that could be fixed by non-intrusive workaround (like the one pointed by Richard) or most probably by fixing carriage alignment.