Verboten Screw Cover. Who Can Make Them?

[PaulTWinterton]

After being so careful and protective of my original cover, I broke it while installing the #1 air intake runner.  DRAT!

So I took measurements of the cover, inside and out, and created a 3D model to get printed.  I have no experience with 3d printing so this is all new to me.  I delivered an STL file to a retail 3d print shop.

 

Here's what I learned (at the consumer level anyway):

1.  FDM (Fuse Deposition Modeling) uses ABS filament and does not create enough definition on a small part like this.

2.  SLA  (Stereo-Lithography Apparatus) uses resin and creates a much more defined model.  Unfortunately only transparent green was available.

 

VERBOTEN SCREW Cap2_.avi

 

The AVI file above may or may not work, depending on your OS.  Let me know if it's a problem to play.

 

I know that some FAQ members are well-versed in 3D printing.  If anyone would like to add their expertise, it would be much appreciated.  If anyone wants a copy of my STL file please PM me.  It would be nice to have a supplier of these covers.  But it won't be me.

 

 

Edited March 11, 2017 by PaulTWinterton

[ray_]

Paul have you checked with the rebuilders to see if they are available?

 

Cheers,

[PaulTWinterton]

Well...no.  Never thought of that.    I'll try on Monday.

Wouldn't that be nice.

[lilmo]

It looks like the cap is designed to break when removed, so the service manager at the dealer can deny warranty claims if the cap is missing.

[Zorac]

fdm can do some pretty good detail, maybe just make the wall a little thicker then it would work?  

 

 

[PaulTWinterton]

The green resin SLA cap "clicked" into position nicely, but I did revise the STL model with a slightly thicker wall anyway.

 

The white FDM pieces wouldn't even fit.  I guess shrinkage from the production process.  As well, the icon on top was missing and the indent inside (for the head of the screw) was poorly interpreted. 

 

 

 

 

[Driv3r]

Take the old cap and do a 3D scan, it will save it as sla file, then print it. Go to another print shop, my printer has every colour.

[Zorac]

if the printer is calibrated right, shrinkage shouldn't be an issue, although I find tolerances can be a bit rough with detail depending on the size

[JerryC]

SLS (Selective Laser Sintering) in nylon is the best process I've used for a functional part like this one. I've used SLS, SLA, and FDM in my job, but keep coming back to SLS for functionality and accuracy. It will be made of real nylon, and the details will come out pretty well. Nylon is probably what BMW had it made from, originally. SLA resin is not stable over time, let's just say it's good for visual samples, and that's about all. FDM will probably make a part this size into somewhat of a blob. I've heard it's getting better, so look around at different vendors.

A couple places to get this done in SLS are:

https://express.stratasysdirect.com/quote.aspx?productID=4

https://www.protolabs.com/3d-printing/

You may run into problems due to the small part size. Model the part as several pieces, connected together with runners, to reach the minimum size requirement. You cut them apart when your receive them. This little trick can save you some money, too.

Have it quoted in CNC also. Then there are no accuracy or durability concerns, it's a real part. Both Stratasys and Proto Labs will quote it. Again, it may be too small. Try Fathom in Oakland, CA also. They'll help you figure out the most economical way to make this.

[PaulTWinterton]

14 hours ago, JerryC said:

SLS (Selective Laser Sintering) in nylon is the best process I've used for a functional part like this one.

 

This looks like the route to go. Thanks for that.

 

I'm hoping for a one-off, or a super small run to satisfy a small group of owners.  I'll give Stratasys, Protolabs, and Fathom a try.  Cheers.

[tomphot]

Along this line, how many Tii owners still have the caps on?  Mine was most likely Long gone by the time I bought car.

[jgerock]

16 hours ago, Zorac said:

shrinkage

...like a frightened turtle...

[ray_]

1 hour ago, tomphot said:

Along this line, how many Tii owners still have the caps on?  Mine was most likely Long gone by the time I bought car.

 

Mine's still on.

 

 

[PaulTWinterton]

2 hours ago, tomphot said:

Along this line, how many Tii owners still have the caps on?  Mine was most likely Long gone by the time I bought car.

 

Anyone want to estimate the number of tiis still on the road?  I'd think that 90% need that cap.

[mvliotta]

Although my cap is still there, used Paul's file to make one in PLA. Wrong material for these, I think, but wanted to see how it would come out.

 

 

Quality from my son's printer is not terrible, but not seamless. 

 

Vince