Adventures with a Flashforge

[FWLR]

Signed up now. Apparently they are having some problems with their email server.....

[philipy]

Thingiverse can be a bit flaky sometimes.

[ge_rik]

TinkerCAD I am hugely impressed with. It has an extraordinarily well designed interface - I'm used to 3D drawing packages having a steep learning curve, but this is a remarkable piece of software which has clearly not just been through many iterations of user testing but some very focused development. It's incredibly quick to get going and produce something I can throw at the slicer and get printing. I will say I did buy a cheap graphics tablet at the same time as the printer, as I find doing these things with a mouse virtually impossible (hats off to those who manage it) but even so it really has a low threshold for actually producing something! Just as well, as I need to get these wagons sorted before the last post goes...

Hi Simon
You might find my most recent blog post useful. I've walked through how I drew the parts for a Southwold open wagon (nearly 200 screenshots). Rather than ploughing through the whole thing, I've indexed some of the more useful techniques at the end.

Though, as you say, TinkerCAD is remarkably intuitive.

https://riksrailway.blogspot.com/2020/1 ... -with.html

Rik

[SimonWood]

You might find my most recent blog post useful. I've walked through how I drew the parts for a Southwold open wagon (nearly 200 screenshots). Rather than ploughing through the whole thing, I've indexed some of the more useful techniques at the end.

Thanks Rik, I had read it, and your post on the Southwold van, but really helpful and I intend to go through using it as a 'worksheet' just to get to grips with those techniques once work finishes.

Meanwhile I've moved on from printing livestock to people... When Trevor's 4415 driver came through, I was already printing my first human, and a knight of the realm no less.

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But can you guess which one?

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"Great men are forged in fire. It is the privilege of lesser men to light the flame."

Then I threw Trevor's pre-sliced driver at the printer. In this case I did break off most of the supports before I put him in the cab of 4415, but otherwise he is as-printed.

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Look at the fingers!

P1320025.jpg (6.95 KiB) Viewed 4602 times

There are several hairy filament bits that need tidying up, but that shouldn't prove tricky.

P1320027.jpg (7.15 KiB) Viewed 4602 times

[ge_rik]

You're a braver man than me (Gungadin).... I've not yet had a go at printing figures.

Rik

[SimonWood]

I printed out some of the Loco Remote track. I am hugely impressed with the design for this - especially the turnout. I can see that if I'm not careful, I will be printing myself a micro layout before I know it...! (In fact I've already dusted off a plan I made when I was playing with RailModeller Express...)

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However, as with the Lego, the bits that are supposed to clip together, don't... It's not really a problem with the track, as a bit of filing will resolve the issue. But from a diagnostic perspective, I'm starting to think there's a pattern here, that somehow the default print settings are making things slightly larger/thicker than designed...

[FWLR]

Looking through Thingiverse, I can't find people to view. I put people in the search and I have got loads of gamers and other stuff....

[philipy]

But from a diagnostic perspective, I'm starting to think t,here's a pattern here, that somehow the default print settings are making things slightly larger/thicker than designed...

Can't speak for your m/c or custom software, but normally they reckon that prints are around 5% undersized from the drawing and certainly I find that. Printing a 4mm hole, for example, normally needs to be drawn at about 4.25mm diam.
On that basis, since your software is apparently customised to your m/c I guess its possible that somehow they have allowed for the shrinkage by default?

[SimonWood]

Looking through Thingiverse, I can't find people to view. I put people in the search and I have got loads of gamers and other stuff....

I haven't found many people, aside from my War Doctor, which is why MakeHuman is so appealing!

Can't speak for your m/c or custom software, but normally they reckon that prints are around 5% undersized from the drawing and certainly I find that. Printing a 4mm hole, for example, normally needs to be drawn at about 4.25mm diam.
On that basis, since your software is apparently customised to your m/c I guess its possible that somehow they have allowed for the shrinkage by default?

If it was a uniform shrinkage or enlargement, wouldn't the Lego blocks still work with each other even if not with real Lego? And wouldn't my track clip together - the studs being enlarged (or shrunk) by the same amount as the holes for them...? The gauge of the track seems to be spot-on too...

[philipy]

I don't think it is uniform actually, for a start I think it shrinks differently along the grain than across it, and I suspect it will also depend on the printing temps and layer heights as well. Plus, in a wider sense I suspect it will also depend on the source of the filament.

[SimonWood]

I don't think it is uniform actually, for a start I think it shrinks differently along the grain than across it, and I suspect it will also depend on the printing temps and layer heights as well. Plus, in a wider sense I suspect it will also depend on the source of the filament.

If it's not uniform, that makes compensating rather complicated!

[Trevor Thompson]

Wow - this is something I have not played with.

I know that when I print holes they come out undersize - but I cant tell you by how much.

Everything I draw is made to a known scale I actually measure everything in Sketchup. As in add dimensions (its because I was an engineer). So I can measure printouts against designed dimensions.

In fact I might design a box of known size print it and measure it. I will let you know the result!

Trevor

[Trevor Thompson]

PS

That driver does come out well doesn't it - as you point out the fingers are unbelievable.

I wonder how it will come out from a resin printer?

Trevor

[Trevor Thompson]

Some information on shrinkage.

I have just measured the victorian milk churn in sketchup - and the 9 of them I have printed.

Height in the software 45mm. In reality between 45.56 and 45.67mm.

diameter in the software 27.95mm - in the printed versions fairly consistently 26.14mm in on direction and 26.26mm in the other.

So the model is about 10% too high, about 93.5% of the width it should be and 93.4% deep.

So suggesting 5% shrinkage in the plane of the bed is about right.

trevor

[SimonWood]

So suggesting 5% shrinkage in the plane of the bed is about right.

This is certainly tolerable for most things - I certainly wouldn't have noticed it if I hadn't printed things designed to slot together. But now I am wondering why if two parts designed to fit together are 5% smaller than they shouldn't be, why they still don't fit together? It takes me a few seconds with a file to enlarge the holes on each piece of the track so that sections fit together. They don't "clip" as they should, but since I plan to fix them down as part of a micro layout, that's not a problem... really this is not a big issue at all...

But a little part of me wants to spend far more time than that "fixing" the problem, either by messing with the STL files to compensate the drawing, or to fiddle with the slicer settings to find out why holes come out too small... And because I know these pieces have been designed to be printed - and other people have printed them successfully - it seems to me that the issue must be one with the slicer/printer, albeit not just with a particular one as we know from this thread that people with different machines have experienced it. But, at least as far as FlashPrint goes, I cannot see any setting that would obviously be connected with the print encroaching on a hole... except maybe for "Shells" and even then I assume that these are all printed within the boundaries of any given solid...?

[SimonWood]

I wonder how it will come out from a resin printer?

I look forward to finding out when you try it!

[philipy]

But a little part of me wants to spend far more time than that "fixing" the problem, either by messing with the STL files to compensate the drawing, or to fiddle with the slicer settings to find out why holes come out too small..

I don't know anything about your Flashprint, but I'm not at all sure that a slicer can do the sort of editing that you need, to fiddle with adjusting things like Lego studs and holes. Certainly Cura can flip, multiply, move, etc and the scale function allows scaling by different amounts in the three planes, but I doubt that adjusting one small element of an stl file is possible. I think you need to go back to a CAD file to do that. I know it is possible to import stl's into Sketchup but don't know if Tinkercad can accept them.

[ge_rik]

......I know it is possible to import stl's into Sketchup but don't know if Tinkercad can accept them.

You can import .STL, .OBJ and .SVG files into TinkerCAD

Rik

[SimonWood]

I don't know anything about your Flashprint, but I'm not at all sure that a slicer can do the sort of editing that you need, to fiddle with adjusting things like Lego studs and holes. Certainly Cura can flip, multiply, move, etc and the scale function allows scaling by different amounts in the three planes, but I doubt that adjusting one small element of an stl file is possible. I think you need to go back to a CAD file to do that. I know it is possible to import stl's into Sketchup but don't know if Tinkercad can accept them.

I have already augmented an STL file in TinkerCAD - adding to a Lego block. (This is one reason making Lego appeals to me - the ability to create new pieces, or converters - a bit like this Duplo to Brio adapter.)

I can definitely scale in FlashPrint, and duplicate and (I think) mirror. Maybe scaling differently in the 3 planes will resolve it? But I'm hoping there's some universal setting I can find... I've discovered "elephants footing" this morning, and read up on solutions, but on examining the prints I'm doubtful that's the problem. Think I need to keep looking...

[Trevor Thompson]

Simon

The Flashforge slicing software will allow all of the general manipulations like scaling, duplicating and so on. But you will have to go into the CAD package to adjust specific parts such as the pip size.

I have been looking more carefully at shrinkage and I think it is a lot less than I said last night - I think I got my math wrong. More on that in the place I posted it last night.

Trevor