BMW 507 Cabrio 1957 - Elvis Presley's one - Based on a Revell old kit 1:24

[CrazyCrank]

Morning guys

 

I did numerous tries since yesterday, and finally opted for 0.35 mm braces, thinned on the front by including chamfers on the drawing.(Thanks @hendie )

I printed it numerous times, and this early morning, the result, just taken out its resin bath and water cleaning was EXCELLENT ! 👃

 

BUT....there's always a but ! 

I blow the plate with my airbrush and left the print drying a few minutes... after which I noticed that ALL braces were twisting ! 😪

So, this print is now in the trashcan ! 😡

 

I've decided, since all my drawing parameters, slicing parameters,  number and position of the supports are now correct, that perhaps my resin (RESIONE W90B) was guilty. 🙄

So I change the resin for ELEGOO try water washable resin and started a new print.

 

Heerunder the result just after printing and water cleaning:

 

  

 

  

 

And after an UV curing I started immediately after having dried the print with my airbrush, I obtained a good if not excellent result on 10 over 16 parts

 

 

 

Of course, despite the adding of chamfers on the braces, they  still look a bit too thick, but I can't due better, due to the physical and technical constraints of my actual printer (Mars 1st generation version Pro), that I need to change for a 8K one

 

Nevertheless, really excellent result and fitting, and I'm pretty happy with it !

 

I've obviously to clean up a bit more the part, and to detach all the other good parts of the plate, and doing the same job for them, in order to have several spare parts,.

Indeed, as you can probably imagine, the part is very delicate and fragile, and its handling during the painting process could result in broken braces...

 

And also to print the left grill , whose drawing is already done:

 

 

See you later for next step and thanks for watching

 

 

[hendie]

I'm glad my suggestion helped. 

It looks like you created an entirely separate drawing for the left grill - did you realise there's a mirror function in Chitubox, where you could just have mirrored the part and saved having to create another drawing?

 

The grill looks excellent in place and should look even better once painted up

 

 

*** edit ***

 

If I were to print those grills, I may try rotating the orientation 90 degrees so that they are standing up - i.e. Taller than they are wide.  The way you have them oriented at the moment means that the horizontal spars (the longest spars) are pulling off the FEP sheet during printing and that may be leading to distortion.  If you rotate the parts 90 degrees then the short vertical spars now become horizontal, and are supported by the thicker outer frame. That will put much less stress on the spars as they are being released from the  FEP film during printing. Obviously, it will take a bit longer to print but it may improve part quality.  

There's no reason you couldn't try both orientations in the same print, and see if there's a difference in the output.

 

 

 

[Neddy]

Knowing almost as much about 3D printing as Eric Pickles did about hang-gliding I'm in no position to offer technical comment but can only admire (a) your perseverance, and (b) the excellence of the result!

[Bengalensis]

Seriously good work!

That's the way; never give up 👍

[CrazyCrank]

4 hours ago, hendie said:

I'm glad my suggestion helped. 

It looks like you created an entirely separate drawing for the left grill - did you realise there's a mirror function in Chitubox, where you could just have mirrored the part and saved having to create another drawing?

 

The grill looks excellent in place and should look even better once painted up

 

 

*** edit ***

 

If I were to print those grills, I may try rotating the orientation 90 degrees so that they are standing up - i.e. Taller than they are wide.  The way you have them oriented at the moment means that the horizontal spars (the longest spars) are pulling off the FEP sheet during printing and that may be leading to distortion.  If you rotate the parts 90 degrees then the short vertical spars now become horizontal, and are supported by the thicker outer frame. That will put much less stress on the spars as they are being released from the  FEP film during printing. Obviously, it will take a bit longer to print but it may improve part quality.  

There's no reason you couldn't try both orientations in the same print, and see if there's a difference in the output.

 

 

 

 

Thanks Hendie for the advices 👍

 

I didn't know that there's a mirror function in Chitubox, but I know there's mirroring functions in Fusion 360 !

So, I didn't create a new drawing starting from zero for the left grill.

I just started from the right grill, created a plan on the front face of the grill, and I mirrored the bodys of the right grill relatively to this plan (time spent 10 seconds), then I removed the bodys of the right grill (time spent 10 seconds) and that's it !

 

That said, your advice is much appreciated, I'll try that next time !

 

And I'm going to start a new print following your second advice, for the right grill, before printed the left one 👍

 

1 hour ago, Neddy said:

Knowing almost as much about 3D printing as Eric Pickles did about hang-gliding I'm in no position to offer technical comment but can only admire (a) your perseverance, and (b) the excellence of the result!

You're too kind with me, Neddy 😎

 

1 hour ago, Bengalensis said:

Seriously good work!

That's the way; never give up 👍

 

Thank you so much Jörgen !  Coming from you, that's an even greater compliment. 👍

 

[CrazyCrank]

Good afternoon mates

 

I tested twice  Hendie's last suggestion to printing the parts vertically, and I'm finally bit disappointed because:
- The print comes out very nicely regarding the size and thinness of the spars, even though I didn't put any support on them
- BUT (there's always a "but" ) amongst 9 right grills, only 4 have their spars perfectly straight, and amongst 9 left grilsl, only 1 is good.

 

I've so right grills enough to get at least one correct after handling during painting, but only 1 left grill, at the moment.

 

 

Once cleaned, I got this:

 

 

Rather good, but, under magnifying glasses, the fitting isn't perfect with the body...it seems there's a very  little lack of width for each parts, rather visible on the inner or outer edge, depending on how the parts are positioned !

 

I could modify slightly the drawing, without having the certainty that the print will fit better, or wait to see how it comes out once painted and dry fitted...

 

I'll probably chose the second option ! Because the chrome paint will probably modify the global aspect of the front of the car once the grills are put in place....and in the worst case, I can live with a little defect !

(At least...I think so )

 

See you later

 

 

[Bengalensis]

Seems to me that you're ready to paint the best pair you have. With a little luck all will be fine 👍

[hendie]

9 hours ago, CrazyCrank said:

I could modify slightly the drawing, without having the certainty that the print will fit better, or wait to see how it comes out once painted and dry fitted...

 

Remember that once you have the STL  files in Chitubox, you can make copies and scale them in any of the X, Y, & Z axes independently. 

I've done that a few times, mainly when it's a hard to obtain dimension from a model, and it let's me test different dimensions without having to create a new 3d model every time.

 

How long did you leave the prints for drying?  I often find that very fine features don't come out of the printer 100% straight but as the print dries, everything comes back into line.

 

 

[CrazyCrank]

8 hours ago, hendie said:

 

Remember that once you have the STL  files in Chitubox, you can make copies and scale them in any of the X, Y, & Z axes independently. 

I've done that a few times, mainly when it's a hard to obtain dimension from a model, and it let's me test different dimensions without having to create a new 3d model every time.

 

How long did you leave the prints for drying?  I often find that very fine features don't come out of the printer 100% straight but as the print dries, everything comes back into line.

 

 

 

Yes Hendie, I know this function, and have already used it (for my dashboard particularly), but here, the little lack of width concern only the central half of the edge, not its corners, so, if I resized in Chitubox, I could match better on the central half, but could also become too large on the corners !
My prints dry generally 1 hour away from light before UV curing.
In my case, the curious thing is that :
- sometimes, immediately after the end of the printing, some parts have straight spars, other are twisted. And nothing changes after drying and UV curing
- Sometimes, immediately after the end of the printing, all parts have straight spars, I wash them and the spars twist quickly  and strongly during the drying step !
- Sometimes, after curing, some sparts that were twisted become straight !

 

So, now, I print multiples copies of the same item, and I keep only the best ones

 

[Brandy]

The fit issue could simply be irregularities in the moulding of the body. I would be tempted to print slightly oversize and file the edges of the openings to give a tight fit.

 

Ian

[CrazyCrank]

2 hours ago, Brandy said:

The fit issue could simply be irregularities in the moulding of the body. I would be tempted to print slightly oversize and file the edges of the openings to give a tight fit.

 

Ian

It's likely that I'll do that if the fitting remains too much imperfect with the painted grills.

The lack of width, at first sight,  doesn't exceed about 0,15-0,20 mm, so barely 1% of the total width !

 

[HOUSTON]

IMMACULATE  Work.

I am very  much impressed  by your work.

FLAWLESS!!

Thank you. 

[Toftdale]

Actually I prefer the kit part!.....😅😂😂 (obviouslyI'm joking😁). Incredible perseverance to make it just right.  She's truly going to be a one off - Andy 

[CrazyCrank]

On 7/8/2023 at 8:32 AM, HOUSTON said:

IMMACULATE  Work.

I am very  much impressed  by your work.

FLAWLESS!!

Thank you. 

 Thank you so much, Houston

 

14 hours ago, Toftdale said:

Actually I prefer the kit part!.....😅😂😂 (obviouslyI'm joking😁). Incredible perseverance to make it just right.  She's truly going to be a one off - Andy 

 

Actually I prefer it too....BUT only for the chrome quality ! 😉

 

I'm currently working on the parts chrome painting and I've tested REVELL CHROME on a spare worn  part ...

 

It's very expansive but gives a real chrome look :

 

 

On this picture, it's been sprayed from the can without any previous base coat and has dried 48 hours.

You can now touch it delicately but you must not press the surface. 48 hours more drying are needed, but, even after 96 hours drying, I could be not durable enough to be handled during the attaching process.

 

According to Barbatos Rex, It seems that in order to give it a good strength and durability, it should be clear coated with several thin coats followed by one wet coat of DELUXE MATERIALS BD67 "Looks like Glass".

 

 

 

I printed on last Friday some left and right grills, enlarging them in width from 1.5 % (so 0.3 mm more), and the parts fitting was very incorrect.

 

So, I've printed another plate of the previous parts, at 100% scale, and had a good surprise: 4 good left grills and 4 right ones 😎

 

I'm now going to make new "chroming" tests on spare parts before "chroming" the grills, using three methods to see which one I could finally use

- Gloss black GRAVITY primer from "Chrome set", then Alclad Chrome, and at last Alclad Aqua Gloss clear coat

- REVELL CHROME, 96 hours drying, Alclad Aqua Gloss clear coat

- REVELL CHROME, 96 hours drying, DELUXE MATERIALS BD67 "Looks like Glass".

 

I've already told you, I'm stubborn 🙄

 

See you later for next episode

 

[Fnick]

Another chrome product to try is greenstuffworld chrome. I used it on my e type. Barbados rex also has done a review on his channel.

 

Nick 

[Fnick]

Link to review

 

 

 

 

[CrazyCrank]

24 minutes ago, Fnick said:

Another chrome product to try is greenstuffworld chrome. I used it on my e type. Barbados rex also has done a review on his channel.

 

Nick 

 

Thanks @Fnick for the advice and link . I've ordered this chrome to test it too

 

Has you clear coated it ? And which clear ?

Is it durable (with or without clear) ?

Can you handle the non chromed chromed parts with bare fingers ?

Can it withstand rubbing ?

 

[Fnick]

It wasn't clear coated. Once it's dry it can be handled . It can be buffed to give it more sheen.

 

Here's what it looks like on the Jag 

 

It looks a bit dark but I only gave it a couple of light coats as suggested in the video. With hindsight I would have probably done three possibly a tad heavier. Still looks the same 8 months later. I can't see anywhere where it has dulled.

 

Hope this helps

 

Nick

[CrazyCrank]

12 minutes ago, Fnick said:

It wasn't clear coated. Once it's dry it can be handled . It can be buffed to give it more sheen.

 

Here's what it looks like on the Jag 

 

It looks a bit dark but I only gave it a couple of light coats as suggested in the video. With hindsight I would have probably done three possibly a tad heavier. Still looks the same 8 months later. I can't see anywhere where it has dulled.

 

Hope this helps

 

Nick

 

Fantastic !

I ordered this chrome today and will test it.

How long does it take to dry out completely? and to be handled safely ?

 

[Fnick]

I sprayed the parts one evening and handled them the next day without any problems.

 

One important thing. You need a gloss black undercoat before spraying the chrome. I tried to get away with semi gloss as that is all I had to hand at one point at it just didn't work.

 

Nick

Edited July 9, 2023 by Fnick

[nick]

Only just caught up with this, not sure why you’re having print problems, you should be able to print something that size easily enough. 
 

have you got your printer/resin dialled in with calibration pieces? It’s well worth spending the time to do this. 

What layer height and anti aliasing settings are you using? For very fine stuff, I sometimes go down to 20 microns layer height. I generally draw my supports in fusion 360 as chitubox supports do too much damage for parts like that, it will also stop your warping issue if you draw in slotted blades under the rails of the grill, it will keep it true during curing and be easier to remove. 
like this:-

 

 

I don’t want scarring from supports so have drawn all the support structures as part of the model, with thin, interrupted ‘blades’ as the contact points, this technique would be ideal for your grilles. it’s stronger that ‘dots’ and easy to remove with a sharp knife. 
 

it would also allow you to print the grilles flat which I do all the time, this angling stuff is overrated IMHO you’re not mucking about with angles and half lines/anti aliasing if the piece is square on, you’re not going to get any suction issues with something like that either. 
 

also molotow chrome refills thinned with isopropyl and airbrushed is the only chrome to use for my money. 
 

drop me a pm if you want any help with printing/drawing the grilles, I’ve got 8k machines I can easily run a few off for you on if necessary. 

 

great work BTW, I’m very envious of your painting skills!

[CrazyCrank]

6 hours ago, nick said:

Only just caught up with this, not sure why you’re having print problems, you should be able to print something that size easily enough. 
 

have you got your printer/resin dialled in with calibration pieces? It’s well worth spending the time to do this. 

What layer height and anti aliasing settings are you using? For very fine stuff, I sometimes go down to 20 microns layer height. I generally draw my supports in fusion 360 as chitubox supports do too much damage for parts like that, it will also stop your warping issue if you draw in slotted blades under the rails of the grill, it will keep it true during curing and be easier to remove. 
like this:-

 

 

I don’t want scarring from supports so have drawn all the support structures as part of the model, with thin, interrupted ‘blades’ as the contact points, this technique would be ideal for your grilles. it’s stronger that ‘dots’ and easy to remove with a sharp knife. 
 

it would also allow you to print the grilles flat which I do all the time, this angling stuff is overrated IMHO you’re not mucking about with angles and half lines/anti aliasing if the piece is square on, you’re not going to get any suction issues with something like that either. 
 

also molotow chrome refills thinned with isopropyl and airbrushed is the only chrome to use for my money. 
 

drop me a pm if you want any help with printing/drawing the grilles, I’ve got 8k machines I can easily run a few off for you on if necessary. 

 

great work BTW, I’m very envious of your painting skills!

 

Hi @nick, and thanks for this long comment.😎

I've not calibrated my printer with a calibration piece ("rook" for example) since....I don't remember ! So, I'm currently printing a calibration piece
I set usually the layer height to 20 microns and turn the antialiasing ON
I understand perfectly your explanation about supports, CHITUBOX ones and yours.
My recent parts, right and left grills, but also the vent frame situated in front of the windscreen, came out perfectly except for the left grill, printed at the same time than the right one, on the same plate, vertically (following Hendie's advice) :
Amongst 8 copies of the left grill 3 have a slight de-lamination on the first layers, and 2 are twisted, the 3 other are perfect.

When my printer is calibrated, I'll try your method with supports.

 

Regarding the chrome paint, Molotov, thinned with IPA and airbrushed gives incredible results, but the chrome is very fragile, even after 2 weeks drying, and, in my experience, doesn't support handling, even wearing gloves !

How do you proceed with your Molotov painted parts ?

 

[nick]

That was a bit long wasn’t it! Sorry. 
 

here’s a good calibration article to read with the pieces I use 

 

https://all3dp.com/2/best-resin-printer-test-print/

 

the rooks aren’t helpful as you don’t know what settings ELEGOO used to generate the STLs, with the above pieces you can fine tune line width etc. 

 

I would disable anti-aliasing for fine pieces, it has the potential to take material away and when you’re down to very fine tolerances you don’t really want that. 
 

as to Molotow, I hadn’t noticed it being fragile? Maybe I’m just much more heavy handed painting than you (I’m sure I am looking at your results) so possibly I just dollop more paint on them you do. I only thin my molotow slightly too. 

[CrazyCrank]

@nick Here is the result of my first calibration test

 

The Elegoo mars Pro settings for my Elegoo water washable resin:

 

 

The Chitubox  picture

 

 

The print:

 

 

It seems I've lost just a few details:

- the last right hole isn't visible, and the 8 previous are not hollowed (due to technical specs of my printer ?)

- The 3 last right cylinders are broken

 

So ,it's not so bad calibrated....your thought ?

 

I'll try with 9 seconds exposition instead of 10.

 

 

[CrazyCrank]

Re Morning all

 

Here is the result with 9 s of exposure time instead of 10s:

 

 

The print is better detailed as we can see that:

- 12 rounded holes are hollowed instead of 10

- Only the 2 last rectangular holes are not perfectly hollowed instead of the 3 last on the 10s print

- We can't see the 3 last cylinders but I swear that they were present before the part cleaning 

 

So a bit better, I'm going to give a go with 8 s exposure time