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


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3 minutes ago, Pouln said:

The dash looks good to me, although I did not compare it to the real thing.

What is the thickness off the material after printing?

I indeed see this warping happening with very thin printed items. Strengthening at unseen places tend to remediate this.

 

Thanks Poul, for the comment and the advice 👍

The thickness is about 1.0 mm.

When my current tests are finished, if necessary (i.e, if I'm always unhappy) , I'll add some strengthening stuffs  😉

 

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Morning everybody :)

 

My tests are not yet not finished but it's already possible to draw conclusions.

 

On the photos below, you can see a comparison between :

- On the right: 103% size prints left to dry almost 48 hours. On the rear it dried on its supports, and on the front, it dried free of supports. Design V7.

- On the left: 103% size prints with the same drying conditions, but with a modified design which increased the thickness of the wall. Design Called V8

 

52343874177_4052547d3d_b.jpg

 

What we can see:

- There is a curvature on the straight  lower portion on the 4 drafts,

- This curvature is much less important when the draft has dried on its supports. This is visible for the V7 and V8 drafts

- And it's much more important on the V7 drafts (thinner wall)

- The shrinkage is bigger on the V7 drafts which have thin walls than on the V8 ones, with thicker walls.

- And the size reduction is significantly bigger for the drafts which dried without supports (about 3.5 mm vs 2.0 mm)

 

Anticipating such results, I'd quickly decided not to wait more for incorporating on the design new structs on non visible sections, that strengthen  the build and intend to prevent the bending.

I took this opportunity to modify of the meters surrounding , to prevent the waves you can see on the picture above

 

I've printed this design 100%, 101, 102 and 103%, and measured the sizes just after printing, just after UV curing and then after 1, 2, 12 and 24 hours of drying.

But, this time, I've left dried the 4 drafts on their supports, and the supports left attached on the printing plate.

And the results are already much more different.

 

52344830071_406fae4e84_b.jpg

 

There is really no bending, and the shrinking varies from 1.09 to 1.27 mm after 24 hours drying. 😎

The 103% draft could even be used for my purpose as its size is actually only 0.25 mm longer than what's needed (51.3 mm vs 51.04), provided that it does not shrink further or bend when detached from its supports.

 

So, I go on with my tests !

I have obviously to left them dry in these conditions until 48 hours (so 11 pm today), and then I'll detach the supports from the printing plate, and will do new measures tomorrow 11 pm

At last tomorrow 11 pm, I'll remove all the supports, and will let the 4 drafts dry 24 hours more before final examination and measures: bending ? more shrinkage ?

Hopefully, there won't be any bending and no additional shrinkage. Fingers crossed !

 

This is very encouraging, and I'm going, asap, to print new drafts in 104 and 105% size, in case these first drafts shrink further in the coming days ...

 

Apart from that, you can see how well these drafts are printed, with a faithful reproduction of the drawing details.
Once the design has been completed with the necessary mounting brackets, and the choice of enlargement factor decided, the final print will be at a layer thickness of 20 microns, instead of 50 for the drafts. The quality should be even better!

 

See you later with more tests results :)

 

 

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Afternoon gentlemen :)

 

Update of informations about distortion and shrinkage of my dash 3D prints:

 

The V8 versions (wall thickness increased but no reinforcement structs), that dried after having been detached from the printing plate had finally, after 48 hours drying :
- for those that dried over their supports a slight distortion and a average shrinkage of 2mm
- And for those that dried without their supports a major distortion and an average shrinkage of 3.5 mm

 

The V9 versions (wall thickness increased and reinforcements structs), had finally after having dry 48 hours on their supports, themselves attached on the printing plate, then 24 hours more with supports detached of the printing plate, and at last, 24 hours more detached of their supports:
- Horizontal and vertical distortion: Absolutely none
- An average shrinkage of 1.40 mm


The draft which size has been increased of 3% in the slicer has a final size of 51.00 mm, when 51.04 mm is the theoretic expected size for an optimal fitting on the bodywork.

 

The tests are still running with 104 and 105% drafts for 2 days.


But it's now clearly evident that 103 or perhaps 104% are the good factors.


And so, I can move my interest to the fixing brackets of this new dashboard  :)

 

Little size comparison between the kit part and the 3D printed one (103%)

 

52350202196_b6889602c1_b.jpg   52350518884_db3532c52b_b.jpg

 

This photographs don't allow a true appreciation of the size because the shapes are slightly different and the parts don't sit the same way on the mat.

My part is in fact 0.3-0.4 mm shorter than the kit one when you take the measure at their bottom with a caliper.

That's why I think that the 104% has to be tried too, once fully dried Tuesday evening.

 

You can also notice that the meters area on the kit part is larger than on mine: it's true, there is a 0.9 mm difference, but on the kit part the meters are to far part , and I say that because I based my measurements on close frontal pictures of the meters. I do think that I'm closer of the truth.
At last, you can notice that the meters area is nearer the centre of the dash on my part than on the kit part: Same remark than above !

 

Anyways, it will do the job !

 

See you later for next episode :)

 

 

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1 hour ago, Bengalensis said:

Very nice work, your patience and methodic approach is admirable!

Thank you so much, @Bengalensis :)

 

hereunder some pictures of a first test fitting:

I've had to cut out drastically the reinforcement structs I did because they hit the bodywork when you tested the adjustment.

Doing that, the left lower part of the dash broke a bit, as you will see.

I've glued temporarily the 103% dash on the windshield frame with Micro liquide Tape,  and I can already notice that there's a little lack of material, so the 104%, if not the 105%, will probably more appropriate.

Then I've put the set n the first (broken) bodywork, in order to see how it comes out:

 

52350610558_357e7880b6_b.jpg  52350792285_3ffc365a01_b.jpg

 

52350684554_43719b611a_b.jpg

 

Globally, this test confirms that the shapes are good, and that fixing brackets ares not mandatory needed, but I think I'll add them, to secure the fastening and prevent ungluing :)

 

See you soon :)

 

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Evening guys :)

 

Hereunder is the modified 3D design which incorporate some slight improvements and especially fixing brackets:

 

 

52349735457_54884cbc72_b.jpg52351110200_923a565934_b.jpg52350930008_5f8af7fc51_b.jpg   52350686776_0606131e30_b.jpg

 

Going to 3D print it in draft mode (50 microns layer) tomorrow in  103%, 104% and 105% and will be test fitted 4 days later !

 

Model making requires a great deal of patience, especially when one small part determines the success or failure of the whole project !

 

Stay tuned if you like :)

 

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Good afternoon gentlemen :)

 

It's been a while since my last post !

 

My tests are now finished and here is what I can say about  the resin 3D prints, their shrinkage and their tendency to twist:
- With my last V10 draft, I incorporated reinforcement structs
- I've printed 100%, 101-102-103-104 and 105% drafts
- The prints dried 96 hours, 48 attached to their supports, themselves fixes to the printing plate, then 24 hours only on their supports and at last 24 hours free of any support.


In this way, contrary to the previous tests without reinforcement structs or drying free of supports since the UV curing, there was absolutely no twisting, even after having detached the prints form their supports.
And the shrinkage has been very moderate during the first 48 hours, and very low after.
It reached an average of about 1.3 mm for all the sizes after 96 hours, of which 1.0 mm during the 48 first ones.

 

52366643301_abf26bb178_b.jpg   52366661961_2c0a4fe3f5_b.jpg

 

52367086335_2282e5eec8_b.jpg

 

The 103 and 104% prints are the ones whose size is closest to the required dimensions.

 

I've made a test fitting of the 103% and 104% on the windshield frame, where the dash will be glued, and the 103% is the best, at the moment (because I don't know what will happen in terms of shrinkage with the final prints in 20 microns layers)
The lateral reinforcement structs had to be cut out for a good fitting of the dash and hereunder you can see some pictures I took in a hurry, after a temporary glueing (with canopy glue) of the dash on the windshield frame, and the frame just sat on the first bodywork (the broken one):

 

52366619556_76267c05e4_b.jpg   52366619596_c6cb1f5a98_b.jpg

 

52367045560_21d411a1dd_b.jpg   52366619601_46ce7e6ed7_b.jpg


Some little improvements have to be done on the 3D design before the final printing, but I'm now very happy of the way this turned out :)

 

So, I'm now going to do this job and print several dashes in 103% at 20 microns layer, and let them dry the same way I described above.

In the mean time, I'll glue the tub on the body and then cut out the doors ...

 

Stay connected if you like :)

 

 

 

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10 hours ago, Spiny said:

If you're not totally sure how it's going to dry with 20 micron layers, would it be worth putting a couple of 104% dashes in there just in case? The dash certainly looks very good in situ.

You're right, @Spiny, I'll do it, almost in the same time because I own 2 printing plates for my Elegoo. So, 1 plate with 103% (x6) and 2 hours later, I'll can start a new print with 104% (x6) on the second plate 😉

 

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Morning guys :)

 

I've slightly modified some things and added 2 missing parts:
- The ignition key housing, below the meters on the right of the steering column 
- The stand for the  choke handle on the left end underside of the dash

 

52368705743_99932b26ac_c.jpg   52368892700_3b0ce30742_c.jpg

 

52368473426_eb35a9ba3e_c.jpg   52368892630_5dc2686f49_c.jpg

 

All that stuff has been sliced, 3 pieces in 103% and 3 in 104% ( @Spiny 😉 )

 

52368481776_b2d3ecf9d0_c.jpg

 

And will be printed today in 20 microns layers.

Hopefully the prints will be as good as the previous ones 🤞

 

See you soon :)

 

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Are you doing any post-curing after the parts come out of the vat?

I'm really surprised by the amount of shrinkage you are seeing in your prints.  I've been printing various objects for several years now and I've never seen anything close to that level of shrinkage.  I haven't done any studies per se, but on the occasions I have measured parts (where I need tight dimensional accuracy) I have only measured shrinkage in tenths of a millimeter. If I remember correctly I saw shrinkage of around 0.3mm in a thin walled part nearly 40mm long.

One thing I have seen is: in parts that haven't been post cured, the resin will continue to shrink and dry out until the parts start pulling themselves apart, i.e. cracks will start to appear. This process takes place over several months though. 

When parts are first printed, they are not fully cured when they come out of the printer - each layer is cured enough to hold its shape well enough for the next layer to be printed.

I use an Elegoo Mars with standard elegoo resin. I post cure with either a UV pen, a UV  nail lamp, or simple daylight. It all depends upon size, geometry, and how soon I want to start using the part.

 After a print run I will wash the parts in a 2 bath IPA, then let parts dry naturally. This usually happens in 30 minutes to an hour. At that point I will do the post cure.

 

This is a model I designed, printed, and assembled using entirely 3D printed parts, of which there were around 100 or more printed parts.

 

PC070017.jpg

 

If I experienced the degree of shrinkage you are describing I would never have been able to assemble the model as each part will shrink differently according to things like wall thickness, geometry, overall mass, and print orientation.

I should mention that model is 1/48 scale so the wingspan is around 300mm or more.

 

I can't help but think that something is amiss, either in your setup, or in your process.

 

 

 

 

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1 hour ago, hendie said:

Are you doing any post-curing after the parts come out of the vat?

I'm really surprised by the amount of shrinkage you are seeing in your prints.  I've been printing various objects for several years now and I've never seen anything close to that level of shrinkage.  I haven't done any studies per se, but on the occasions I have measured parts (where I need tight dimensional accuracy) I have only measured shrinkage in tenths of a millimeter. If I remember correctly I saw shrinkage of around 0.3mm in a thin walled part nearly 40mm long.

One thing I have seen is: in parts that haven't been post cured, the resin will continue to shrink and dry out until the parts start pulling themselves apart, i.e. cracks will start to appear. This process takes place over several months though. 

When parts are first printed, they are not fully cured when they come out of the printer - each layer is cured enough to hold its shape well enough for the next layer to be printed.

I use an Elegoo Mars with standard elegoo resin. I post cure with either a UV pen, a UV  nail lamp, or simple daylight. It all depends upon size, geometry, and how soon I want to start using the part.

 After a print run I will wash the parts in a 2 bath IPA, then let parts dry naturally. This usually happens in 30 minutes to an hour. At that point I will do the post cure.

 

This is a model I designed, printed, and assembled using entirely 3D printed parts, of which there were around 100 or more printed parts.

 

PC070017.jpg

 

If I experienced the degree of shrinkage you are describing I would never have been able to assemble the model as each part will shrink differently according to things like wall thickness, geometry, overall mass, and print orientation.

I should mention that model is 1/48 scale so the wingspan is around 300mm or more.

 

I can't help but think that something is amiss, either in your setup, or in your process.

 

 

 

 

 

Hi Hendie

 

Thanks for your comment
I use currently water washable resin W90B from RESIONE.
Previsouly I used standard resin, and then ABS like resin from ELEGOO.
When the parts come out the bath, I wash them 4 to 10 minutes (it depends of the size, shape etc.) in water, currently, then I blow out the water with my airbrush and then I UV cure them immediately during 4 to 15 minutes (it depends of size, shapes etc.)
When I used standard or ABS resin, I saw the same twisting on my spare parts after a few days, but I never had to measure the size to see if a shrinkage occurred .

 

It looks like the only difference between you process and mine is that you let dry 30 to 60 minutes your prints before UV curing them.
I'll try your  method for my next parts.

 

That said, It seems that the shrinkage of UV resin  is a problem well known by professionals , according to what's written on this website:  How to compensate UV resin shrinkage ?

 

It's in French, so I put below the translation of the firsts paragraphs:

 

"

Shrinkage optimization in 3D resin printing explained

When 3D printing resin, liquid photopolymers polymerize and turn into a solid. If shrinkage is significant, it will ruin the dimensional accuracy of your final part. So you want to limit the amount of shrinkage as much as possible. This could be done by first trying to eliminate as much shrinkage as possible through smart material selection. We wrote an article about this earlier. The last thing to do is to optimize your shrinkage and offset settings in the 3D printer to compensate for the last bit of shrinkage left. In this article, we explain a super fast and accurate shrinkage compensation method.

 

Why is there shrinkage in 3D printing resins?

Shrinkage in acrylates and methacrylates occurs during polymerization and is caused by the replacement of long-distance connections via the Van der Waals force with strong, short covalent bonds between carbon atoms of different sea monounities. The replacement of these long distance bonds by short distance bonds, multiplied over millions of bonds are responsible for the overall shrinkage of the material as it changes from a liquid to a solid plastic. This shrinkage can lead to serious problems, including the build-up of internal stresses, resulting in the formation of defects or dimensional changes, which can be responsible for a decrease in mechanical properties. Therefore, it is important to develop and use low-shrinkage materials and to properly control the remaining shrinkage.

 

How to compensate for shrinkage in 3D resin printing?

As mentioned earlier, the first thing to do is to start with a good low-shrink resin. This will eliminate all sorts of problems later on. The last thing you need to do is compensate for shrinkage in the 3D printing software settings. Since this is a mathematical solution averaged over the entire part, the values can be quite off when you have a high shrinkage resin. Another factor to consider is the type of 3D printer you are using. In entry-level resin 3D printers, you don't have many compensation options. Very often, a simple percentage shrinkage or even a manual enlargement of the part by x% is required. For the more professional machines, you have two options that can help you. These are the scaling parameter and the offset value.

 

What do the scaling and offset values do to compensate for shrinkage?

The scale value is the easiest to explain. It will make the part x% larger. So you are actually printing a slightly larger part and if it shrinks during printing, your dimensions will be accurate. But that factor alone doesn't cover the entire compensation. What you will see is that thin parts have a higher percentage of shrinkage than thick parts. This means that if you compensate for the shrinkage percentage on thin parts, it will be over compensated for thick parts, and vice versa. To add another factor, offset solves this problem in professional printers. This setting will add or remove a set amount of microns from the exposed model, regardless of the cross section of the model. To combine the two parameters, you can actually compensate at a very detailed level. Let's see how this works in practice in the next paragraph....."

 

CC

 

 

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Thanks for the info CC.  I'm very familiar with shrinkage and the reasons behind it - my day job is heavily injection molding focused. While not exactly the same, there are many parallels that can be drawn between the two processes and the molecular bonding/shrinkage is one of those.  

 

For clarification, that 30 - 60 minute drying time is not an absolute - sometimes I will leave the print to dry overnight (all depending upon when the print finishes). On occasion I have used the airbrush to blow dry parts ready for post cure. I do try not to leave them longer than that though.

 

I have only ever used Elegoos resins and I have never found the need to change as those resins work well for me. I wonder if the resin itself is to blame for the excessive shrinkage?

 

 

 

 

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3 minutes ago, hendie said:

Thanks for the info CC.  I'm very familiar with shrinkage and the reasons behind it - my day job is heavily injection molding focused. While not exactly the same, there are many parallels that can be drawn between the two processes and the molecular bonding/shrinkage is one of those.  

 

For clarification, that 30 - 60 minute drying time is not an absolute - sometimes I will leave the print to dry overnight (all depending upon when the print finishes). On occasion I have used the airbrush to blow dry parts ready for post cure. I do try not to leave them longer than that though.

 

I have only ever used Elegoos resins and I have never found the need to change as those resins work well for me. I wonder if the resin itself is to blame for the excessive shrinkage?

 

 

 

 

 

I wonder too the same thing, though I faced the same twisting issue with ABS like and standard resin on spare parts I left on their supports during a few days.
Nevertheless, my first impression is that the shrinkage is earlier and bigger with water washable resin !
It's a not a big problem, since I've it now documented and measured !
 

CC

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Evening gentlemen :)

 

I've printed to 103% and 104% the final version V12, at 20 microns layers instead of 50 microns for the drafts

 

The print is absolutely perfect, just when I've cleaned it and after UV curing.

 

52372535165_7bc88a0b27_c.jpg

 

BUT, there' always a "but"...After curing, the shrinkage was insignificant and 2 hours after curing, it's only 0.2 mm when it was about 0,75 mm for the drafts at 50 microns  ! 🤔😡

I've obviously to wait the next steps: 12 / 24/ 48 /72 hours drying to see if it will increase or not, and in which proportions.

 

Anticipating an insufficient shrinkage with the 103 and 104%, which wouldn't allow to reach the exact size I need (about 54,3 mm +/- 0,2), I just launched a new print in 101 and 102% .

Decidedly, 3D printing technic parts with 3D resin isn't an easy task 🤔

 

Well, not a big problem, it's just a question of time and tries :)

 

Stay connected 😎

 

 

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Afternoon guys ;)

 

While my tests on 3D printing the dash are going on, I've begun to think about the doors hinges.


Initially, I thought I would be able to fabricate and install the door hinges after having glued the tub inside the bodywork , but my recent tests show that it will not be possible (for me)

So, I've begun to work on them.


My goal if to get an accurate and real cinematic when opening the doors, I mean, when you open the door of a car, its front edge enters the bodywork instead of moving away from it. 
I thought deeply and seen some inspiring videos on Youtube and ... let's go !

As a precaution, I'll  do all my tests on the first broken body, which I reinforced for the occasion so it won't break again.

 

And here is the current state

 

52376856440_e96bcc78de_c.jpg   52376440056_f6715957cb_c.jpg


The hinge has been fabricated with brass tube and 0.5 mm steel wire, a piece of styrène drilled twice 0.6 mm.
The axle of rotation is situated on the inside of the door, on the front edge, that has been thinned of 50% (I've dig a groove at this place)
The few point is inside the body, in front of the door.
A lot of adjustments had to be done, and, temporarily, the position of the styrene piece which goes inside the bodywork has been modified and maintained with adhesive gum (UHU Patafix)


It open smoothly, without catching !

 

52376440076_db6d8d14b9_c.jpg   52375488127_71a4aa1ba3_c.jpg

 

52376661928_85a79bf8d2_c.jpg   52375488092_c9cc4faf83_c.jpg

 

52375488137_3d172e41f9_c.jpg


Now, I've to improve the system, always on the broken bodywork, modifying the styrene piece (Increase its size, modify shapes) in order to avoid the adhesive gum and glue it in place definitely to test the system.
If all's OK, I'll be able to fabricate 2 final hinges for the new bodywork in the same way


BUT, there's always a but:

I shall not leave the unfinished and unpainted  doors definitely glued on the unpainted bodywork.
Indeed, to finish the doors, with their inside face, le filling of the gaps on the front and the rear between the door and its inside, and to paint them, they must be free, and I must have glued the tub inside the bodywork BEFORE, in order to adjust correctly the inside of the door so it fit well with the tub.
So, it's only once that done (the bodywork painted, the tub achieved and glued etc) , that l can put and fix the finished doors, and for that, I will only have a very little free space between the bodywork in front of the door, and the side wall of the tub at this level, to insert the two pieces of steel wire  of the hinge into their respective holes on the styrene piece.
It will be a difficult and painful job, assuming I get there !

 

If anybody see a better and easier solution to this problem, I'll be happy to have him exhibit It ! 🤔

 

See you later :)

 

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2 hours ago, CrazyCrank said:

 

If anybody see a better and easier solution to this problem, I'll be happy to have him exhibit It ! 🤔

No chance mate, you're already operating WAY above my level!  I love the way those doors look when half-open, well worth all the effort you're putting into the hinges.

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4 hours ago, CrazyCrank said:

Afternoon guys ;)

 

While my tests on 3D printing the dash are going on, I've begun to think about the doors hinges.


Initially, I thought I would be able to fabricate and install the door hinges after having glued the tub inside the bodywork , but my recent tests show that it will not be possible (for me)

So, I've begun to work on them.


My goal if to get an accurate and real cinematic when opening the doors, I mean, when you open the door of a car, its front edge enters the bodywork instead of moving away from it. 
I thought deeply and seen some inspiring videos on Youtube and ... let's go !

As a precaution, I'll  do all my tests on the first broken body, which I reinforced for the occasion so it won't break again.

 

And here is the current state

 

52376856440_e96bcc78de_c.jpg   52376440056_f6715957cb_c.jpg


The hinge has been fabricated with brass tube and 0.5 mm steel wire, a piece of styrène drilled twice 0.6 mm.
The axle of rotation is situated on the inside of the door, on the front edge, that has been thinned of 50% (I've dig a groove at this place)
The few point is inside the body, in front of the door.
A lot of adjustments had to be done, and, temporarily, the position of the styrene piece which goes inside the bodywork has been modified and maintained with adhesive gum (UHU Patafix)


It open smoothly, without catching !

 

52376440076_db6d8d14b9_c.jpg   52375488127_71a4aa1ba3_c.jpg

 

52376661928_85a79bf8d2_c.jpg   52375488092_c9cc4faf83_c.jpg

 

52375488137_3d172e41f9_c.jpg


Now, I've to improve the system, always on the broken bodywork, modifying the styrene piece (Increase its size, modify shapes) in order to avoid the adhesive gum and glue it in place definitely to test the system.
If all's OK, I'll be able to fabricate 2 final hinges for the new bodywork in the same way


BUT, there's always a but:

I shall not leave the unfinished and unpainted  doors definitely glued on the unpainted bodywork.
Indeed, to finish the doors, with their inside face, le filling of the gaps on the front and the rear between the door and its inside, and to paint them, they must be free, and I must have glued the tub inside the bodywork BEFORE, in order to adjust correctly the inside of the door so it fit well with the tub.
So, it's only once that done (the bodywork painted, the tub achieved and glued etc) , that l can put and fix the finished doors, and for that, I will only have a very little free space between the bodywork in front of the door, and the side wall of the tub at this level, to insert the two pieces of steel wire  of the hinge into their respective holes on the styrene piece.
It will be a difficult and painful job, assuming I get there !

 

If anybody see a better and easier solution to this problem, I'll be happy to have him exhibit It ! 🤔

 

See you later :)

 

Outstanding work!

I'm sure you thought of this, but don't forget to leave clearance for the side "gills".

I'm going to an auction in 2 weeks featuring a early series 2 unrestored 507.

Estimate is in the $1.8 to $2 mil. range. So yes, i will not be bidding.

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22 minutes ago, Lvp said:

Outstanding work!

I'm sure you thought of this, but don't forget to leave clearance for the side "gills".

I'm going to an auction in 2 weeks featuring a early series 2 unrestored 507.

Estimate is in the $1.8 to $2 mil. range. So yes, i will not be bidding.

 

Thanks for the advice, @Lvp :)

Regarding the "gills", it's one problem I'm focused on, but it will be difficult to avoid a bit of obstruction of them with my styrene  stuff.

I'm currently studying the way to reduce this unwanted side effect 🤔

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Afternoon guys :)

 

I publish always my builds on several sites, and a French modeler, friends of mine, pointed out that I was wrong about the door opening kinematics of the BMW 507 !!!! 😮

And, by the hell, he is right !

 

On his car, when you open the door, the front edge doesn't enter the bodywork as I thought mistakenly.

On the contrary, the front edge of the door swings outwards when it is opened !

 

And he posted 2 photos and a drawing to show me how it worked on this car:

 

52378817886_787b4e4833_c.jpg   52377877427_d5f92444df_c.jpg

 

52379237195_f4e1d24a8c_c.jpg

 

It will be much more easy now with this knowledge, to fabricate the hinges and install them 😎

 

So I go back to my bench to fabricating theses hinges and test them on the broken bodywork :)

 

Stay connected ;)

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Afternoon guys :)

 

A bit of progress today:

 

1/  the tests for the 3D printing of the dash are finished


And the surprise is that the first prints at 103 and 104 %, in 20 microns layers, shrank only  by 0.8 mm in 48 hours, and 0.0 mm after. This is significantly less than with the prints in 50 microns.
So, after 48 and 96 hours, they remain far too big fir fitting correctly in the windscreen frame.

I launched 3D prints in 101 and 102 % a few hours after the previous print, but on a second and new printing plate. And after less than 6 hours, the base of the supports began to unstick from the plate.
After 12 hours, all supports were totally detached from the plate. Nevertheless, I went on with the tests.
And those print have shrunk a bit more than the 103 and 104%, which remained, them,  strongly attached on the printing plate during the 48 hours I wanted them to be fixed.
Luckily, there has been no twisting at all !

So today, after 96 hours drying, the 101% is too short, but, surprisingly the 102% print has almost exactly the length I expected : 54,25 mms vs 54.27 (on the drawing).
It has shrunk 1.08 mm since the 102% drawing was 55.35 mm (54.27 for the 100% drawing), so exactly 2%.

I have printed three 102% dashboards . 
One has been damaged when I cut the supports out, but I have 2 in excellent state.
I've made a test fitting  in the windscreen frame and it fits perfectly.
It remains to complete the dash, to paint it and to keep it for the final state of this build, when I install it on the body.

 

52381284909_a4378b39ca_c.jpg   52380974216_d1b9f7881a_c.jpg

 

2/ The tests for the door hinges progress correctly

In fact, you just have to reverse the hinge, i.e. place the pivot point inside the body, and the fixed point inside the door, to reverse the movement. When the door is opened, its front edge moves away from the body, instead of going inside.

It remains now to make 2 final hinges on the same principle, improving the shapes, the mechanical aspect and the aesthetics of the thing.


The hinge, once the door is cut, will be precisely positioned and fixed in the body and will stay there during the rest of the assembly.
The two horizontal metal extensions of the hinge shall be inserted with gentle friction on brass or aluminium tubes glued in the correct position inside the door.
The door will be detachable from the hinge once the hinge position is permanently fixed; it can then be worked freely, improved, painted etc.
It could then be easily glued in its final position on the hinge pins at the end of the assembly process.

 

52381400855_a134554f45_c.jpg   52381224853_245617fa34_c.jpg

 

52381412980_70a87751d6_c.jpg[   52380055602_ee73c4fbf4_c.jpg

 

52380056272_a8d14479c7_c.jpg   52380056797_3deb0530eb_c.jpg

 

Stay connected if you like :)

 

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38 minutes ago, Spiny said:

I'm not sure which I respect more, your hinge making and 3D design/printing skills or your patience. Either way, the build is shaping up to be another stunner.

Thanks for this kind praise 😎

But I wouldn't say patience, rather tenacity, obstinacy :)

 

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