Pre-announcement announcement: N scale school bus kit

[pennsyfan1361]

The clear casting looks good. Do you know if the clear will stay clear or will it yellow in time? When I talked to the guy from made2scalemodels he was having a problem with demold of clear casting messing up his Fishbowl bus molds and wearing them out.                   Rich

[rswinnerton]

Conrail had 'em in blue or orange. Also. Ed's law applies in relation to them being used today. The school bus I rode as a kid is still going. Good 'ol bus 14A!

[DKS]

The clear casting looks good. Do you know if the clear will stay clear or will it yellow in time? When I talked to the guy from made2scalemodels he was having a problem with demold of clear casting messing up his Fishbowl bus molds and wearing them out.

Not sure about yellowing. The product specs do not mention it, but that's not too surprising. As for going through molds, I more or less anticipated it.

Also. Ed's law applies in relation to them being used today.

Sure! The church down the street from me has two or thee of them, painted maroon. I also pass them all the time being used as Department of Corrections shuttles. And don't forget to rust up a few for the local junkyard.

[SkipGear]

David,
 Did you ever get your vinyl cutter going? If so, it sounds like you laser cut the sides for the master and have the file for it on hand, you can use that to cut window masks. Would make life so much easier to paint with precut/spaced window mask set. I make them all the time for the RC car bodies, this is just a much smaller application.

[peteski]

DKS: was the master pattern 3D printed?  Just curious...

The clear version looks great. I agree that a clear coat of Future or some other clear might improve clarity of the windows. Painting the model will be time consuming but IMO, well worth the effort.

Unless you can have them Tampo-printed! 

[Ian MacMillan]

I'm in for clear. Could the body be cast in clear and the frame, wheels in black? Or is it all one mold?

[Alaska Railroader]

DKS: was the master pattern 3D printed?  Just curious...

I laser cut these for David, he did the magnificent drawings. Been honing my 3D lasering quite a bit this past year.

[peteski]

I laser cut these for David, he did the magnificent drawings. Been honing my 3D lasering quite a bit this past year.

3D laser cutting?  That is a technology I have not ever heard of being used for model railroading. Neat!

[peteski]

Many thanks for the great feedback, everyone!

I'm happy to say clear works, although it is a bit harder to demold. As you can see, the windows are slightly frosty, so they look white-ish, although they will pass light. I will see if this can be improved...

DKS,  if you were to either polish the master pattern or coat it with a glossy finish, that should improve the transparency of the windows.  It might make the castings easier to demold.  But I'm sure you already know that. 

[Chris333]

3D laser cutting?  That is a technology I have not ever heard of being used for model railroading. Neat!

It's a raster image with various shades of grey to cut at various depths.

[DKS]

It's a raster image with various shades of grey to cut and various depths.

Chris has described it correctly in principle. In practice, it takes quite a bit of, well, practice--on both ends: getting the drawings right, then fine-tuning the laser to successfully generate the masters. You can create a surprising amount of depth this way, assuming the right materials and techniques are employed. As it happens, a school bus is ideally suited for the process as the overall form is blissfully devoid of large, compound curves. The body is comprised of about 33 flat parts assembled to create the full form.

Unless you can have them Tampo-printed! 

That is not outside the realm of possibility... but not for the initial run.

David,
 Did you ever get your vinyl cutter going? If so, it sounds like you laser cut the sides for the master and have the file for it on hand, you can use that to cut window masks. Would make life so much easier to paint with precut/spaced window mask set. I make them all the time for the RC car bodies, this is just a much smaller application.

Yes, I do have the Silhouette running. However, I cannot import the laser drawing into the cutter app, and re-drawing it would be time-consuming. I'm doing all that I can to keep the costs down.

Could the body be cast in clear and the frame, wheels in black?

That is the plan.

DKS,  if you were to either polish the master pattern or coat it with a glossy finish, that should improve the transparency of the windows...

This is in the works as I write.

[daniel_leavitt2000]

Holy crap, Dave do you ever sleep? I thought I was the only one to lurk here after 4.

[DKS]

Holy crap, Dave do you ever sleep? I thought I was the only one to lurk here after 4.

Sarcoidosis. An auto-immune disorder that typically affects the lungs (they're trying to self-destruct in the process of attacking a non-existent infection). Bottom line, I often cough up one or both lungs when I have an episode.

[peteski]

I happen to be a night owl too. 

Thanks for all the answers David!

As far as the vinyl masks go, I was also thinking of doing that on my CraftROBO cutter.  That would certainly make painting easier.  My original thought was to place the bus on its side on a scanner then scanning it. Then I could trace the windows in Corel Draw into objects for cutting out the masks. But if someone (ahem) already had the bus drawings in a Corel 10 format then I could just use those for the cut outlines.

[Ike the BN Freak]

I'd be in for a few, and without the etched details.  Don't have many other vehicles that do, so don't see the need for background trucks too.