• Updated 2023-07-12: Hello, Guest! Welcome back, and be sure to check out this follow-up post about our outage a week or so ago.

3D Print Replica HD 20 SC Enclosure?

Trash80toHP_Mini

NIGHT STALKER
1. Printing in two parts, flat. Will involve generating support material... I'm just not sure how well this will go. Would look something like this. The bed isn't deep enough to print it as one piece so it would need to be two. The green on the left is support material - I'll do a smaller print to test that. 
HRMMM  .  .  .  If you can print split sections of top and bottom for unification with ABS cement, mechanical fasteners and having a honeycomb support rib grid inside you may have modeled mold parts suitable for investment casting production? The seam lines between halves could be cleaned up giving a unified mold pattern.

I've experimented with producing large panels using a similar process. Laying up an ABS glop of dissolved pipe connectors on a modeling clay form for eventual fiberglas reinforcement. I've an unlimited supply using waste from hull layup from a yacht builder I know for FRP parts. I came up with what's probably the ugliest CRT case quarter panel extant.

Reproducing smaller case sections using investment plaster negative molds (water soluble after casting a part) from your model should be investigated. If you purposely sectionalize a positive mold form with thin extensions along every rounded edge for sanding smooth afterward, it may also be possible to cast a multi-part mold reusable until it fails or inevitably wears out.

Dunno, gotta think it over outside my stream of drivel process. Time to make more coffee. :blink:

 

Trash80toHP_Mini

NIGHT STALKER
I'm in no major rush on that.  We might still need it to figure a good mounting solution. 
Good idea there, modeling the existing support structure for a 5.25 inch drive for printing would be much better. Very low cost adapters to the 3.5 inch form factor are readily available a 5.25 inch structure would support CD and removable cartridge mechanisms of every sort.

edit:

View attachment 27636

View attachment 27744

That's the AppleCD SC mechanism support structuret, the only one for which I've posted pics, but they serve the purpose.

Standoff from bottom is less for the HDD version as the CD case is about that much taller. Lack of depth of the new design would put DB-25 based passthru connector web next door in the PSU backplane, fan (unlikely, but if needed) can probably remain in the same spot. Gotta take some measurements. I'm seeing a lump-on-a-rope of the type used for IDE-USB-SATA adapters clipping into its molded home, positioning its standard power cord plug receptacle on the backplane

 
Last edited by a moderator:

Swolfington

Well-known member
I don't have much to add except this is looking really quite impressive and I love how you salvaged the failed print. Looking forward to your next update!

 

PotatoFi

Well-known member
Time for an update! Since last posting about this, the only 3D modeling tool I could use was SketchUp, which is actually pretty bad for designing mechanical parts. Since then, I've learned a new tool: Fusion 360! I even spent $300 on a real Fusion 360 license a couple of days ago, so I am really committed now. Today, I sat down and got the HD20 SC modeled up:

Screen Shot 2020-09-28 at 9.38.43 PM.png

There it is, a real, fully parametric model! Parametric means that there are variables (parameters) assigned to certain aspects, like case thickness. Right now it's 7mm, but it's one variable to change it to 5mm. Or 10mm.

Depth is a variable as well, so you can quickly toggle between it being "Mac-depth" and "full HD 20SC depth". 

This model will give me a much, much better canvas to work on. I can also bring some details to life that I couldn't with SketchUp. For example, the corner fillets aren't actually consistent on the real HD 20SC. Some of the corners have a different radius. I absolutely couldn't use unique values in SketchUp, but with Fusion 360, that stuff is super, super easy.

There are some other details to add to the model:

  • Back I/O cutout
  • Apple Logo
  • Correct corner radii (mentioned above)
 

aeberbach

Well-known member
Nice job! Linear patterns for the repeating lines too?

Did you have to buy a license though? I thought that for general maker use it was free until you make $100k in income with it?

 

PotatoFi

Well-known member
Nice job! Linear patterns for the repeating lines too?

Did you have to buy a license though? I thought that for general maker use it was free until you make $100k in income with it?
Yep, I used a Rectangular Pattern Constraint in a 2D sketch to generate those. Worked like a charm. That was a ton of manual work in SketchUp.

As for purchasing the license... normally it is $500/yr. They announced some changes to the non-commercial version that are totally fair, but would make using it a bit of headache for me. That combined with a nice $300/yr discount made me decide that it was worth it to make the jump. I am using it almost daily, so I decided that for less than a dollar a day, I would have the "real deal". Plus, my SCSI2SD Bracket and Mac ROM-inator Clip sales will eventually pay for the license. And I have several ideas for other parts that people might be interested in (all with the free files, paid prints model). Not_bad.jpg!

 
Top