Water tank rivets problem

If you are having problems with your 3D printer or have had a problem and discovered a great solution, then share your experiences here.
User avatar
-steves-
Administrator
Administrator
Posts: 2412
Joined: Thu Jul 28, 2011 1:50 pm
Location: Cambridge & Peterborough

Water tank rivets problem

Post by -steves- » Wed Apr 07, 2021 9:16 pm

I tried printing the water tank. It told me there was something wrong with the mesh in cura but I continued with it and when it printed all the rivets just fell off at touch at the base of one of the sides, like they are not attached properly. I "doubt" this is a printing issue as the printer has been turning out perfect print after perfect print up till now. Suggestions? Could it be because I am not using a Mac for some bizarre reason? Any help would be appreciated.
The buck stops here .......

Ditton Meadow Light Railway (DMLR)
Member of Peterborough and District Association
http://peterborough.16mm.org.uk/

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Welsh Pony

Post by philipy » Wed Apr 07, 2021 9:33 pm

-steves- wrote: Wed Apr 07, 2021 9:16 pm I tried printing the water tank. It told me there was something wrong with the mesh in cura but I continued with it and when it printed all the rivets just fell off at touch at the base of one of the sides, like they are not attached properly.
My guess would be that the rivets are separate, i.e that the backs of the rivets are still there. I've had similar problems before myself.

Edited to add: I think I'm correct. I've just imported the stl of one of the sides into Sketchup and then twisted round to look at the inside of the side. You can see all the rivets are still discrete items just poking through the skin, not an actual part of the solid side.
Screenshot 2021-04-07 21.38.22.png
Screenshot 2021-04-07 21.38.22.png (108.38 KiB) Viewed 5155 times
Edited again because I've manually intersected one of the rivets and repaired it and you can see the difference in this next screenprint:
Screenshot 2021-04-07 21.47.33.png
Screenshot 2021-04-07 21.47.33.png (116.05 KiB) Viewed 5153 times
Philip

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Welsh Pony

Post by Trevor Thompson » Wed Apr 07, 2021 9:42 pm

I didn't have that problem myself.

I will have another look at the files. One of the things which will have an impact is that my printer corrects the stl file as part of the slicing process - so I may be printing successfully things that cause others problems. Rivets however often cause me problems - they seem to like to hover over the surface rather than on it.

I will check.

Trevor

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Welsh Pony

Post by Trevor Thompson » Wed Apr 07, 2021 9:43 pm

Yes that makes sense - I do that to try to stop them falling off - I need to attach them.

I have added a new zip file to the original posting. The new sides have been modified to intersect the faces of the rivets and the framework. I have also rerun solid inspector.

Hope these are better.

Trevor
Last edited by Trevor Thompson on Wed Apr 07, 2021 9:59 pm, edited 1 time in total.

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Welsh Pony

Post by philipy » Wed Apr 07, 2021 9:57 pm

Trevor Thompson wrote: Wed Apr 07, 2021 9:43 pm Yes that makes sense - I do that to try to stop them falling off - I need to attach them.
A couple of suggestions, don't know if will help you.
I assume that you draw one rivet and then multiply it at a fixed distance? So, after drawing the first one, have alook at the back of it and make sure it is hollow i.e it doesn't have a solid base, before you place it and multiply. Also don't do it as a 'group'. If you do it as a group, you then need to ungroup it to get it to stick, but that won't work when it is sticking right through, rather than stuck to the surface.
Philip

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Welsh Pony

Post by Trevor Thompson » Wed Apr 07, 2021 10:03 pm

Thanks

You learn something new every so often!

Trevor

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Welsh Pony

Post by philipy » Thu Apr 08, 2021 9:00 am

Trevor,
I've just downloaded and looked at your revised water tank stl.

I'm not sure in what way you've altered it, but it doesn't seem to have changed the actual drawing? I suspect that you've simply grouped the whole thing again, but if so I don't think that helps, because as I understand it, slicers ignore groupings.

I've just taken one of your new sides and exploded it right down to the basic drawing and then removed the inside face of the tank, to see what is going on.
Then I took three of your rivets off and relkaced thrm with three that I've just drawn, keeping the same diam as yours but only 0.5 long.
On the following screen shot, you can see my three. The RH one was placed on the surface as a group and then ungrouped and as you can see it is an integral part of the skin.
The middle one is still grouped and hasn't intersected and this is how the RH one looked before I ungrouped it.
The LH one is grouped and has a back on it so it is a solid cylinder not a tube.
Screenshot 2021-04-08 08.46.01.png
Screenshot 2021-04-08 08.46.01.png (114.66 KiB) Viewed 5146 times
The same view from the front.
Screenshot 2021-04-08 08.57.40.png
Screenshot 2021-04-08 08.57.40.png (139.59 KiB) Viewed 5146 times
Philip

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Welsh Pony

Post by Trevor Thompson » Thu Apr 08, 2021 12:23 pm

All of the models I have drawn which incorporate rivets have the same problems. It is really an issue about how well do I understand sketchup, and how it works. I have got away with this for this long because my printer and its dedicated slicing software can correct these things and usually prints what I expect - so for me and others with the same printers it isn't an issue. That doesn't mean I don't need to know what I'm doing - I often come up with problems getting sketchup to do what I want! I am sure there are others who would welcome the deeper understanding.

So I will go back over one of my drawings and try to sort out the rivets! If I understand correctly what I am looking for is for the inside view to show a hole - and for the outer surface of the component to show a continuous face.

I understand that the rivets need to be ungrouped - I didn't actually group them but drew one, copied and pasted it , selected both and copied and pasted them. I think I also have to intersect the faces in the component itself. Can I have the rivets as components and the frame as a component and successfully intersect the faces - that surely must work? I will follow your instructions later and see how I get on!

Trevor

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Thu Apr 08, 2021 1:17 pm

Trevor I'm a bit snowed under today but I'll try to do you a blow by blow on how I do it - no doubt there are other ways too!
Philip

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Thu Apr 08, 2021 6:40 pm

This may get a bit long, so bare with me!

How to create equally spaced multiple copies of an object such as a rivet in Sketchup.

Note for illustration I've created a small block and deleted the back face to enable a view from the inside:

1) Draw a circle of the required diameter ( these are 0.5mm radius - 1mm diameter ). The picture shows the circle is visible from both outside and inside.

Image

2) Extrude it to required depth ( I've used 0.5mm extrusion). This picture shows it is extruded above the surface and from the inside is a hollow cylinder that is part of the 'skin' of the base block.

Image

3)'Select' the rivet, then copy and paste, then make the copy into a group.

Image

4) Copy the group and do Ctrl V to paste it onto the surface of the block twice.

Image

5) This picture shows, from the inside, that both are on the surface but have NOT properly joined it.

6) Explode one of the groups. From the inside it will still look the same except the blue square bounding box has disappeared. The circular base lines will look thick, so zoom in until you can see the individual segment lines of the 'circle', then use the pencil tool to draw over one of the segment lines, click at the end of the segment and the whole circle will change to thin lines.

Image
7) Click in the centre of the circle and it will go mottled, then RIGHT click and select 'erase', or simply hit your delete key, and the circle infill will disappear and the hollow rivet will become visible.
Image
This routine is handy if you need to do any corrections subsequently or add an odd one for some reason, but it would obviously be a real pain to cover a long length of tank side with rivets this way! Fortunately there is a much easier way to do that, although it does take a bit of getting used to!

OK.... go back to (2), i.e you have a hollow rivet on the surface, with no back face.

8 ) Draw or place a rivet where you want the line of them to start. Then draw a guide line in the direction you want the rivets to run.

9) Select the start rivet so that it is shown in blue, then select the 'Move' tool ( 4 arrows) and then IMMEDIATELY hit the Ctrl button. You should see a small ' + ' appear at the bottom corner of the 4 arrows.( I can't show this because tools don't show in screen shots for some reason)

10 ) Click on the start rivet and slide the cursor in the direction you want to multiply it - you should see a duplicate rivet move away from the original.

Image

Let go, then type the separation distance you want between each rivet, ( I've used 2.5) then type the number of duplicates that you want ( I've typed 4) and they magically appear. If you look inside you'll see they all are hollow and therefore part of the model.

Image

11) It is possible to do it the other way round by typing the overall length and then the number of rivets you want followed by / instead of x i.e 50/20
Philip

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Water tank rivets problem

Post by Trevor Thompson » Thu Apr 08, 2021 10:59 pm

Philip

Many thanks for the detailed help.

There seem to be differences for the iMac version. I can get the "+" symbol next to the move arrows, and I can get it to move the copy a set distance. However I cant work out how to make it copy 10 rivets 2.5mm apart (for example). typing 2.5 x 10 has no effect. 2.5 enter 10 is the same. i have tried 50/20 as well - no effect either. It is probably a iMac difference.

I can "correct" rivets as you have suggested. However it still leaves me concerned. I use "components" extensively. Lets say the rivet is a component (which it is). I can copy and paste them, I can copy them a set distance apart along a guide line. I SHOULD be able to successfully print an assembly which consists of a number of components - without having to copy and paste all the components into a single component - which is basically what you are doing. It is good practice to use components, for a number of reasons.

I have been printing assemblies of multiple components so far - successfully with my software ignoring the message in solid inspector about nested items. On the basis that there are nested items - all of the components. They print successfully for me like that . So how do I reconcile this?

Trevor

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Fri Apr 09, 2021 6:33 am

I've had another look at my instructions above, just in case I've not quite written what I intended. Simplified version below:

I must say that I've never used components myself. I did try but couldn't get on with them and I find groups work perfectly well and can easily be modified or altered if required. I don't think that should make any difference in this case though, since it is multiplying/copying an entity irrespective of what it is.

I've realised that the grouping/ component issue is a slight red herring. It isn't necessary to do either to create a line of similar rivets, simply draw one and duplicate it.
I normally draw a hemispherical rivet which needs to be done at say 10 times to get SU to be able to work with it and then reduce it to whatever size I want and import that into the drawing. To be on the safe side I group it for the import and then park the original and copy the group, but it isn't actually necessary. So my apologies if I've confused things.


1) Draw rivet
2) Highlight it ( turns blue)
3) Select "Move"
4) Hit "Ctrl" ("Command" in Mac?) and small + is added to Move icon.
5) Click and hold on 1st rivet, then drag in the desired direction - a copy appears and moves with the Move cursor.
6) Release mouse
7) Type "2.5" and hit Enter ( the copy should move to the set distance)
8 ) Type "4x" and hit Enter and it should duplicate 4 more so that you end up with a line of 6 in total.

Alternatively to fit a number of equally spaced copies between known end limits:
7) Type "10" Enter
8 ) Type type "3/" Enter, and it will fill in two equally spaced copies between the existing first and last ones i.e 3 equally spaced copies of the original.
Trevor Thompson wrote: Thu Apr 08, 2021 10:59 pm I SHOULD be able to successfully print an assembly which consists of a number of components - without having to copy and paste all the components into a single component - which is basically what you are doing.
I don't know enough about components to be sure, but I don't think there should be any problem with printing multiple components, but I think they need to be intersected to the body to work properly, if that make sense?

Edited to add: I've just had a quick play with a line of simple rivets, as my simplified instructions above.

The final one in the line, I then made into a component so that it was in a small blue outlined box, called "Component#1". I then went through the duplication procedure and it worked fine, duplicating the component and all the copies are components as well. They all have open backs and are part of the underlying structure, but the individual components can still be moved around on the surface or even taken off but still retain the open back structure. I think that is the key factor.
Philip

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Water tank rivets problem

Post by Trevor Thompson » Fri Apr 09, 2021 10:54 am

Philip

Thank you for all the effort you have made on this.

I think we are getting there!

I will have another go.

I can see that a rivet as a component can have an open rear face and be moved around etc. That is probably the important point in all of this. I have got most of the way with copying the line of rivets - and will play with the final details later.

I did see a video on tube which explained why i should use components - rather than groups - but that was a long time ago now so I have forgotten the details. Perhaps I should use both components and groups of components.

So finally I am surprised that the rivets fell off when printing, and the angle framing they were attached to did not separate from the underlying face. When I drew the tank I created a box 2mm thick as the basic side and made it a component. Then I made the vertical doubling which runs down the centre of the tank side again as a box. I made that into a component. Then I made a rivet and made that a component. Then I added a line of rivets inside the doubling strip component. That doubling strip, complete with components was copied and pasted to make the doubling strip at each side of that tank side. I then made two boxes and formed them into a "piece of angle iron" to run along the top of the tank side. I pasted a line of rivets onto the face of the angle iron. I then pasted that component onto the bottom of the tank side and inverted it so that the angle was the other way around.

So we have 3 components (which are vertical lines of "steel strip" with rivets on them), 2 components (which are horizontal lines of angle iron with rivets on them) and a piece of steel plate underneath those components. Last night I removed the bottoms of the rivets on all the components on the one side ( because I used components I only had to alter one vertical and one horizontal component. The rest followed the master component automatically. I am remembering! That is the advantage of using components. So if I have used one rivet component by altering the master component they will all lose their bases ( I think).

Now I started writing this because I wanted to explore this idea. If you have followed all of the above rambling, we now have the angle iron strip (with rivets) sitting on the sheet of steel. Why does that strip not fall off the sheet of steel? If the rivets fell off that should also have fallen off. Perhaps the components which I intend to sit on top of other components should not have a back?

I am particularly interested in these concepts because anything which eliminates errors in the stl file before I slice it will decrease the number of printing errors I experience!

Trevor

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Fri Apr 09, 2021 11:53 am

I think I've followed you!
I can see the advantage of only needing to make alterations to one component for others to alter automatically if you are using multiple instances, or if you use the same component in multiple drawings. It isn't something I've found to be a limitation so far, but I must think on it more.

Re your point about open backs and why your angle strips didn't fall off when the rivets did. It was Steve who had the problem with rivets falling off, so although I have seen that problem myself in the past without knowing why, I don't have direct experience on your drawing.
I've been playing this morning with a simple line of rivets and components:
1) Drew a simple block 50x25x2, took the back off and and made it into a component.
2) Drew a simple 1mm diam circle on the surface of the block component. Looking at the back, the circle shows with a sort of shimmery semi-transparent centre.
3) Extruded the circle to a 0.5mm high rivet. Still looks the same from underneath.
4) Made the rivet into a component, still looks the same but with a blue bounding box.
5) Tried to duplicate the rivet multiple times and it worked perfectly and each one is a component. Looking from underneath, they all have the shimmery face infill. I suspect that this effectively shows the boundary of the component rather than being 'real'.

So it looks as though drawing on the surface of a component works as though the component boundary isn't there, and placing one component onto another makes it join automatically. This may explain why your angles don't fall off.

As for why the rivets are a problem, I may have found the answer to that. I drew a simple rectangular block, made it component and then inserted it through the surface of the block, not on the surface. When you look from underneath it is still the complete block, it hasn't joined it. However, placing a 2nd copy (component) actually ON the surface, looks exactly the same as the rivets, with the shimmery infill.

I remember reading that slicers ignore component and group boundaries and treat the objects as though they were combined, but presumably this doesn't hold good if they are not co-planar.
Screenshot 2021-04-09 11.45.16.jpg
Screenshot 2021-04-09 11.45.16.jpg (14.48 KiB) Viewed 5084 times
Philip

User avatar
-steves-
Administrator
Administrator
Posts: 2412
Joined: Thu Jul 28, 2011 1:50 pm
Location: Cambridge & Peterborough

Re: Water tank rivets problem

Post by -steves- » Fri Apr 09, 2021 4:04 pm

As it happens the rivets half way up also fell off, but in a complete strip that pulled away from the tank :dontknow:
The buck stops here .......

Ditton Meadow Light Railway (DMLR)
Member of Peterborough and District Association
http://peterborough.16mm.org.uk/

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Sat Apr 10, 2021 8:21 am

Just out of curiosity, I put one of the original tank sides on to print before I went to bed last night. It has printed pretty well, although there seems to have been some sort of shift half way up. It's pretty subtle and I don't think I can photograph it.
However all the rivets seem to be stuck tight and there is no sign of a strip coming away, at first sight, and I have tried bashing it with the edge of a paint scraper!

So I wonder if the problem is with the slicer settings more than anything else?
FWIW, I just used the settings left from my previous print, which are:
Layer height 0.18
Infill 20%
Wall line count 2
Adhesion none
Support No ( But the overhanging top lip has suffered as a result!)
Print speed 50
Min layer time 30
Print temp 200
Bed temp 50
Philip

User avatar
-steves-
Administrator
Administrator
Posts: 2412
Joined: Thu Jul 28, 2011 1:50 pm
Location: Cambridge & Peterborough

Re: Water tank rivets problem

Post by -steves- » Sat Apr 10, 2021 10:34 am

Sound like it could be me, I will re slice it and try it on the other printer and see what happens. :thumbup:
The buck stops here .......

Ditton Meadow Light Railway (DMLR)
Member of Peterborough and District Association
http://peterborough.16mm.org.uk/

Trevor Thompson
Trainee Driver
Trainee Driver
Posts: 964
Joined: Fri Oct 05, 2018 6:30 pm
Location: South West Wales

Re: Water tank rivets problem

Post by Trevor Thompson » Tue Apr 13, 2021 11:20 am

This is interesting!

I am glad that it isn't quite as it first appeared. I don't really want to have to revisit all my old drawings to re-rivet them so others can use them. In many ways I have finished with these drawings and moved on.

However steves comment about rivets half way up falling off has caught my attention. I have had problems with rivets falling off. I thought I had got around it by dropping them below the surface - so I was sure they intersected the surface. Perhaps a better way is to use a guide line to encourage them to sit on the surface.

Trevor

User avatar
philipy
Moderator
Moderator
Posts: 5033
Joined: Sun Jan 30, 2011 3:00 pm
Location: South Northants

Re: Water tank rivets problem

Post by philipy » Tue Apr 13, 2021 12:23 pm

Trevor Thompson wrote: Tue Apr 13, 2021 11:20 am I have had problems with rivets falling off. I thought I had got around it by dropping them below the surface - so I was sure they intersected the surface. Perhaps a better way is to use a guide line to encourage them to sit on the surface.
I've been doing a bit of investigating myself. When I import an stl into Sketchup, it loses all the component and group boundaries so to some extent I'm guessing what you did to start with.
However, from my experiments, a component rivet will sit ON the surface and 'bond' with it automatically as long as you get the first one in the correct place, ie you get the little tooltip that says " on surface". Once you have the first one in the right place, you can then multiply it as we discussed a few days ago and they will all bod to the surface and shouldn't subsequently fall off.
Similarly if you get two groups or components they will snap together, just position them roughly then zoom in, select and grab one of of the objects and drag to to where it should mate with the other one - I find a sharp/square corner is the easiest place to do it..
Philip

User avatar
-steves-
Administrator
Administrator
Posts: 2412
Joined: Thu Jul 28, 2011 1:50 pm
Location: Cambridge & Peterborough

Re: Water tank rivets problem

Post by -steves- » Tue Apr 13, 2021 4:13 pm

OK, time for an update from me.

There are a number of unprintable stl files in a couple of items, I wont go into it too much, but suffice to say Cura is really not happy with some of them at all and refuses to print certain parts as they are not attached. At the moment my only fix is to import them in to Repetior Host and force a fix on the stl, which most of the time it manages quite well, but sometimes just gets rid of a bit of the file, like one of the borders on a name plate, bizarre!

This is what it looks like in Repetior before and after it fixing it
manifold2.JPG
manifold2.JPG (88.94 KiB) Viewed 4762 times
manifold3.JPG
manifold3.JPG (68.44 KiB) Viewed 4762 times
The buck stops here .......

Ditton Meadow Light Railway (DMLR)
Member of Peterborough and District Association
http://peterborough.16mm.org.uk/

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest