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[Dr.Al]

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I switched to exporting in mm and it is bigger but it still does not fit on the ender3 bed. Which may be correct to be honest. Lol

Hmm... Interesting. I guess there's a difference in bed size - I picked the location of the slices rather arbitrarily to be honest, so the model probably does need a bit of tweaking.

When I imported it to PrusaSlicer, I got this message (which I've never seen before):

After clicking Yes, it looked like this (which also shows up that my rather arbitrary choice of dovetail size wasn't ideal!)

To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both.

To make the segments shorter, there were two things that needed to be done. The horizontal lengths were split into 3; to make them shorter, I split them into 5. I also changed the verticals (split into 2) so they were split into 3.

While I was at it, I added a few construction lines so I could make all the horizontal sections the same total length. This sort of thing takes a bit of getting used to, but once you've decided what you want to do, it's not too hard to get it to work.

It's a bit tedious drawing the lines that join the various different segments together, but it saves a lot of work splitting the parts up as you can do that in one operation.

These are the settings I used to export:

Note the millimetre unit.

One part in prusaslicer:

Zip of all the STLs:

 

[ukracer]

Hmm... Interesting. I guess there's a difference in bed size - I picked the location of the slices rather arbitrarily to be honest, so the model probably does need a bit of tweaking.

When I imported it to PrusaSlicer, I got this message (which I've never seen before):

View attachment 376507

After clicking Yes, it looked like this (which also shows up that my rather arbitrary choice of dovetail size wasn't ideal!)

View attachment 376508

To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both.

View attachment 376509

To make the segments shorter, there were two things that needed to be done. The horizontal lengths were split into 3; to make them shorter, I split them into 5. I also changed the verticals (split into 2) so they were split into 3.

While I was at it, I added a few construction lines so I could make all the horizontal sections the same total length. This sort of thing takes a bit of getting used to, but once you've decided what you want to do, it's not too hard to get it to work.

View attachment 376511

It's a bit tedious drawing the lines that join the various different segments together, but it saves a lot of work splitting the parts up as you can do that in one operation.

These are the settings I used to export:

View attachment 376512

Note the millimetre unit.

One part in prusaslicer:

View attachment 376513

Zip of all the STLs:

Cheers bud. I will try and find time to print out one later today...trying to organise Doctors and District Nurses currently.

 

[Dr.Al]

Cheers bud. I will try and find time to print out one later today...trying to organise Doctors and District Nurses currently.

Bear in mind that the rebate might still be wrong, so check the dimensions before you print

 

[ukracer]

Bear in mind that the rebate might still be wrong, so check the dimensions before you print

Wasn't sure how to check dimensions so I just printed a couple of straights... And you were correct they are marginally out.

 

[Dr.Al]

Wasn't sure how to check dimensions so I just printed a couple of straights... And you were correct they are marginally out.

The easiest way to check a dimension is to click on two points on the model and then click on the tape measure in the bottom right corner:

With reference to the XYZ axes at the top right, that image shows the rebate is 12 mm wide and 12 mm deep.

Fixing dimensions is a case of finding the right sketch / extrude (sketch 2 for the rebate width and extrude 2 for the rebate depth in this case) and editing them to suit.

 

[ukracer]

The easiest way to check a dimension is to click on two points on the model and then click on the tape measure in the bottom right corner:

View attachment 376739

With reference to the XYZ axes at the top right, that image shows the rebate is 12 mm wide and 12 mm deep.

Fixing dimensions is a case of finding the right sketch / extrude (sketch 2 for the rebate width and extrude 2 for the rebate depth in this case) and editing them to suit.

It is the dovetail that does not fit together.
This may well be the PLA not printing bang on size.
If I am printing a nut and bolt I can alter the size of the bolt or thread in the nut. But currently due to time constraints and this stupidly cold weather.
My passatt is getting so bad it freezes daily. (The locks) Cant open the lock. Then when it finally opens the door wont slam shut. Today the battery was flat....doh.
Due to that my small bits of free time are non existent.

I did manage to print two parts out though. They are pretty close so hopefully I can get time to play before xmas.

 

[Dr.Al]

That sort of thing comes down to tolerance on the printer. There are a few good tolerance tests you can do (e.g. this one) to work out how much clearance you need to allow. On my printer, if I print at zero clearance, then parts go together with a bit of gentle persuasion and then hold fast. It sounds like you need to add a bit of extra clearance on your design. That makes it a little bit more complicated, but it's not too hard to model.

I'll try to have a go at giving an example of one way to do it when I get a chance (might not be today though).

 

[ukracer]

That sort of thing comes down to tolerance on the printer. There are a few good tolerance tests you can do (e.g. this one) to work out how much clearance you need to allow. On my printer, if I print at zero clearance, then parts go together with a bit of gentle persuasion and then hold fast. It sounds like you need to add a bit of extra clearance on your design. That makes it a little bit more complicated, but it's not too hard to model.

I'll try to have a go at giving an example of one way to do it when I get a chance (might not be today though).

No rush chap. I am.flat out till next tuesday anyway.

 

[ukracer]

That sort of thing comes down to tolerance on the printer. There are a few good tolerance tests you can do (e.g. this one) to work out how much clearance you need to allow. On my printer, if I print at zero clearance, then parts go together with a bit of gentle persuasion and then hold fast. It sounds like you need to add a bit of extra clearance on your design. That makes it a little bit more complicated, but it's not too hard to model.

I'll try to have a go at giving an example of one way to do it when I get a chance (might not be today though).

was it @Dr.Al who produced this file?

 

[ukracer]

Hmm... Interesting. I guess there's a difference in bed size - I picked the location of the slices rather arbitrarily to be honest, so the model probably does need a bit of tweaking.

When I imported it to PrusaSlicer, I got this message (which I've never seen before):

View attachment 376507

After clicking Yes, it looked like this (which also shows up that my rather arbitrary choice of dovetail size wasn't ideal!)

View attachment 376508

To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both.

View attachment 376509

To make the segments shorter, there were two things that needed to be done. The horizontal lengths were split into 3; to make them shorter, I split them into 5. I also changed the verticals (split into 2) so they were split into 3.

While I was at it, I added a few construction lines so I could make all the horizontal sections the same total length. This sort of thing takes a bit of getting used to, but once you've decided what you want to do, it's not too hard to get it to work.

View attachment 376511

It's a bit tedious drawing the lines that join the various different segments together, but it saves a lot of work splitting the parts up as you can do that in one operation.

These are the settings I used to export:

View attachment 376512

Note the millimetre unit.

One part in prusaslicer:

View attachment 376513

Zip of all the STLs:

I did see this but it passed me by that the dimensions seem to be already defined.. The way I would usually deal with fitting parts is enlarge a nut by 1% or reduce a bolt by the same etc.


Did you have the original file posted in here? Sadly this part goes over my head "To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both."

If I can get my head round that comment and the original file I might have a chance..lol

 

[Dr.Al]

I did see this but it passed me by that the dimensions seem to be already defined.. The way I would usually deal with fitting parts is enlarge a nut by 1% or reduce a bolt by the same etc.


Did you have the original file posted in here? Sadly this part goes over my head "To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both."

If I can get my head round that comment and the original file I might have a chance..lol

Yeah, sorry, that sentence was a bit glib, wasn't it

I'll try to break it down...

To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3).

If a drawing has already been done, you can edit anything in it to tweak dimensions etc. Right-click on a sketch and hit Edit:

The highlighted dimension here is the one I tweaked (I think - I'm struggling to remember all this to be honest):

If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both

When I redrew the dovetails to make it fit on your bed, I put the equal constraint on the lines as described above: there are four lines highlighted in this image:

Close up of the bottom two with just one highlighted:

Those four lines have an "equal constraint" applied to them (by clicking the four lines and then clicking on the = symbol on the toolbar). That means they all have to be exactly the same length and there's only one dimension needed to set the length of all four lines.

Does that make any more sense?

 

[ukracer]

Yeah, sorry, that sentence was a bit glib, wasn't it

I'll try to break it down...



If a drawing has already been done, you can edit anything in it to tweak dimensions etc. Right-click on a sketch and hit Edit:

View attachment 378624

The highlighted dimension here is the one I tweaked (I think - I'm struggling to remember all this to be honest):

View attachment 378625



When I redrew the dovetails to make it fit on your bed, I put the equal constraint on the lines as described above: there are four lines highlighted in this image:

View attachment 378626

Close up of the bottom two with just one highlighted:

View attachment 378627

Those four lines have an "equal constraint" applied to them (by clicking the four lines and then clicking on the = symbol on the toolbar). That means they all have to be exactly the same length and there's only one dimension needed to set the length of all four lines.

Does that make any more sense?

Sadly no mate... I understood this one in fusion and was able to twiddle with the sizes to create the print that fitted. But in on shape not only wont it load here I its not intuitive. But I am now cooking tea so once I get food inside me I will have another read ...I think you highlighted the problem with designing

 

[ukracer]

Yeah, sorry, that sentence was a bit glib, wasn't it

I'll try to break it down...



If a drawing has already been done, you can edit anything in it to tweak dimensions etc. Right-click on a sketch and hit Edit:

View attachment 378624

The highlighted dimension here is the one I tweaked (I think - I'm struggling to remember all this to be honest):

View attachment 378625



When I redrew the dovetails to make it fit on your bed, I put the equal constraint on the lines as described above: there are four lines highlighted in this image:

View attachment 378626

Close up of the bottom two with just one highlighted:

View attachment 378627

Those four lines have an "equal constraint" applied to them (by clicking the four lines and then clicking on the = symbol on the toolbar). That means they all have to be exactly the same length and there's only one dimension needed to set the length of all four lines.

Does that make any more sense?

Just found I had not replied to this yet. my apologies. Sadly it was still not clear as I cant see any 12 dimension in the image. I think I get the principle in that the line needs to be referenced as something and changing one number changes all 4. But I cant see how its "constrained" I can see how a rectangle is constrained by adding the length of 2 lines and one angle. But not the dovetail..lol

 

[Dr.Al]

Just found I had not replied to this yet. my apologies. Sadly it was still not clear as I cant see any 12 dimension in the image. I think I get the principle in that the line needs to be referenced as something and changing one number changes all 4. But I cant see how its "constrained" I can see how a rectangle is constrained by adding the length of 2 lines and one angle. But not the dovetail..lol

It's a 17 mm dimension, not a 12 dimension.

That dimension controls the length of the smaller end of the dovetail. There's also an angle constraint (70°, purple box in the picture below) that sets the angle of the dovetail and another distance constraint (blue box in the picture below) that sets the width of the dovetail (20 mm). The two outer lines that join the outside and inside edges to the angled edges of the dovetail (red boxes below) are constrained to be equal so that the dovetail sits in the middle of the object.

The line that makes up the 17 mm dimension is actually two lines constrained to be equal. That ensures the horizontal line in the middle goes to the middle of the left hand side of the dovetail. The same is true of the two vertical lines on the right-hand side of the dovetail. As the horizontal line is constrained to be horizontal, the two centre points are horizontal and hence the whole thing is symmetrical.

I could have used a "mid-point" constraint instead of splitting the lines into two and constraining them to be equal.

 

[ukracer]

I am.back to this again. I had lost the thread...I finally asked if anyone knew what I had posted in and hurrar I found the original thread. Now all I need is to try and comprehend how to alter the sizes so the dovetail will fit together.

 

[ukracer]

Hmm... Interesting. I guess there's a difference in bed size - I picked the location of the slices rather arbitrarily to be honest, so the model probably does need a bit of tweaking.

When I imported it to PrusaSlicer, I got this message (which I've never seen before):

View attachment 376507

After clicking Yes, it looked like this (which also shows up that my rather arbitrary choice of dovetail size wasn't ideal!)

View attachment 376508

To fix the dovetail issue, I tweaked these two 15 mm dimensions to be 17 mm (in Sketch 3). If I had been more rigorous in the design, I would have drawn some construction lines where those dimensions are set, put an equal constraint on them and then set one dimension to 17 mm, but I was lazy and dimensioned them both.

View attachment 376509

To make the segments shorter, there were two things that needed to be done. The horizontal lengths were split into 3; to make them shorter, I split them into 5. I also changed the verticals (split into 2) so they were split into 3.

While I was at it, I added a few construction lines so I could make all the horizontal sections the same total length. This sort of thing takes a bit of getting used to, but once you've decided what you want to do, it's not too hard to get it to work.

View attachment 376511

It's a bit tedious drawing the lines that join the various different segments together, but it saves a lot of work splitting the parts up as you can do that in one operation.

These are the settings I used to export:

View attachment 376512

Note the millimetre unit.

One part in prusaslicer:

View attachment 376513

Zip of all the STLs:

I don't suppose you can remember if that is a zip file of altered dovetails?

I will print it out in the morning to check anyway but I thought I would ask first.

 

[Dr.Al]

I'm afraid I've no idea. It was a long, long time ago!

 

[ukracer]

I'm afraid I've no idea. It was a long, long time ago!

I can absolutely understand that...I could not even remember the thread I wrote in lol..

 

[ukracer]

I found the model. But still had no luck weaking the dovetails a little. https://cad.onshape.com/documents/f...98363fa5ac6c0740af/e/63d3de290e2ba6f312684654 not sure if you can help ?

 

[Dr.Al]

Happy to help, but you might need to tell me what tweaks you want to do!