The NKP 1000 Series Caboose build thread

[Lemosteam]

Pilling on the door grapes.

INFAMY!

[Lemosteam]

Looks really nice!  Hey, wanna re-scale and print one in Z?   

Re. the doors--you might try put them on the long edge down (hinge side) so there isn't as much vertical.  Or add a pair of supports up to the top corners.

@Jesse6669 Yeah, like the roofwalk.  I know they look terrible, but they are so flexible even after baking that they glue down fine.

[nickelplate759]

I really admire how @Lemosteam is designing this so that orientation and supports can be optimized for various parts of the model.   Too many 3d prints are monolithic which leads to unnecessary compromises in quality.

[peteski]

Uh oh ... what's Peteski going to say about those board gaps? 

Well, to me the optimal board gaps (both, gap width and depth) are on MTL wood reefers, but it seems that most others want to make them exaggerated.  Yes, paint will smooth things out a bit, but even the painted MTL reefers more delicate board gaps are still readily visible.  I'm also very aware that N scale board gaps have to be quite exaggerated to be visible and look "right" to the viewer, and it seems that MTL came up with just the right balance. Again, to me.

I don't have any good way to accurately measure the MTL reefer's board gaps, but visually they seem quite narrow and shallow.  But the only way to tell how other models compare I would have to see them side-by-side with the MTL reefer (both undercoated).

[jdcolombo]

Compared to what I have now (which is a 3d print done via Shapeways 10 years ago), the board gaps are . . . exquisite!

FWIW, here's a body from an early test print by John from a few months back that I painted (by hand, not an airbrush, which I would use on the final version).  Light gray primer and caboose red from Model Flex.  This was a "I just want to see what it might look like painted" quickie experiment.  So anything that looks weird is my fault, not John's.

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John C.

[jdcolombo]

And for comparison purposes, here's what the prototype looked like:

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[peteski]

Well, I know what my opinion about the board gaps is, but we all have different standards.

[dandopinski]

Top shelf stuff!

[Lemosteam]

Still waiting for bulk images to load?

Today, I want to show a little tool I designed to help make some of the fiddly bits, such as a brass cupola strut, the panes of glass, the truss rod and for when the brass etch comes, test fit grooves for the curved side grab, and the two folded 90 degree grabs, for the steps, and for the cupola roof.

First let’s make the cupola strut. Cut a piece of 0.012” brass wire to length and insert it into the groove as shown, just make sure there will be room to bend the wire to the desired angle.







Hold the wire in the groove with a straight blade screwdriver so it does not slide during bending (not shown as I am holding the camera)

Use a flat head screwdriver to bend the wire to the shoulder on the tool. Next, bend the other end to. The edge and slot at the end of the wire can be used to trim the excess wire





Once bent, small adjustments may be required to fit the strut into its gage groove.





If the part gets stuck in the groove, there is a slot that can be used to push the part out.





The ends can be flattened if desired, but keep in mind that slight angles angles are at play in its installed position.



Next let’s make the glass panes. Here is a picture of the tool where the glass panes can be made. There are four recesses show, from left to right, the recess for the lower shell glass, eight are required. Next recess is for the cupola side panes, two are required. The next recess is for the end panes on the cupola, front and back. The last recess is for the door glass.





Remove a small piece of 0.005” clear styrene from its main sheet, maybe 3” x 5”. Each recess represents the WIDTH of the glass pane. Holding each opposite end against a shoulder of the glass recess, make a mark with your blade for one end of the cut line, flip the styrene over and make a similar mark on the opposite side. Lay the styrene down and using a sharp xacto blade follow a straight steel ruler aligned to your earlier marks, and cut off a strip. Do this for each window recess width.

Test fit each strip to ensure it just fits nicely in its respective recess width.



Put the strip in its matching recess and slide to the end of the recess. Using a sharp chisel blade, rest the cutting edge against the groove, making sure the top of the glass is at the end of the recess. Press down on the blade to guillotine the strip, leaving a pane of glass. Repeat for the amounts above, and save the panes for later.





You can test fit the panes into their respective shell locations to make sure they drop in easily.

Now we will make the truss rod assembly, which includes the turnbuckle. Two are required for each model.

Place the 0.010” Phosphor Bronze wire into the groove that runs across the tool, flushing one end to one side of the tool. Hold the wire an trim the other end flush with the other side of the tool:



Use a flat screwdriver as shown to pre- form the first bend. (I could not get the tool to complete the slight bend due to the springiness of the wire).



Next insert the die into the dovetail making sure the end of the wire is under the front shoulder of the die.



Continue pressing the die along the dovetail till the wore is fully bent to follow the lower tool.



Slide the tool out, to release the wire. Flip the bent end over toward the gage end.  You’ll note that manual adjustments may be required. The short leg at the end should be perpendicular to the horizontal end, as seen in the gage groove.



After adjustment test fit the first bends into the gage. If the wire fits without much force, remove and insert the straight end of the wire wire into a printed turnbuckl and slide it toward the first bend.







Next set the wire back into the gage with the turnbuckle within the recess, ensure that the Wilde is fully seated in the gage groove as shown below.



The next three steps will show the remaining end of the wire being formed with turnbuckle in place, and after any bend adjustments, fitted to the gage.









Here is the tool and the finished truss rod assembly for installation later in the process

The tool includes gages for the folded brass corner grab etches, and the curved grab as shown on the prototype image above.

Showing the folded and curved side grabs in CAD as we wait for the etches.

I,age coming soon…

[Mark5]

Next let’s make the glass panes. Here is a picture of the tool where the glass panes can be made.

John, I don't see any pictures in this post.

[OldEastRR]

The trouble with any gaps in wooden side cars is, on the prototype, grime and dust accumulates and sticks down in those gaps, even if the surfaces of the boards are cleaned. You can see that clearly in the prototype photo. How to actually duplicate that effect in N scale may not be possible. How do you weather just the gaps but not the boards?

[peteski]

The trouble with any gaps in wooden side cars is, on the prototype, grime and dust accumulates and sticks down in those gaps, even if the surfaces of the boards are cleaned. You can see that clearly in the prototype photo. How to actually duplicate that effect in N scale may not be possible. How do you weather just the gaps but not the boards?

That weathering technique is called a "wash", using highly diluted paint. The thinned paint remains in the depressions and the surface can be easily wiped clean.  Of course the surface needs to be glossy, but can be sprayed with dull clear coat afterwards.  But with the gaps already being out of scale wide and deep, IMO making them even more visible would likely not be a best thing to do.  Now if those board gaps were very subtle, bringing them out with a wash might work well.

[jdcolombo]

John, I don't see any pictures in this post.

I'm not seeing any photos, either . . .

John C.

[Lemosteam]

I tried a mass upload yesterday so I could copy paste the image links into the text, and they still are not in my gallery.  Guess Ill just have to load them one at a time...

Images added now…

[robert3985]

The trouble with any gaps in wooden side cars is, on the prototype, grime and dust accumulates and sticks down in those gaps, even if the surfaces of the boards are cleaned. You can see that clearly in the prototype photo. How to actually duplicate that effect in N scale may not be possible. How do you weather just the gaps but not the boards?

That weathering technique is called a "wash", using highly diluted paint. The thinned paint remains in the depressions and the surface can be easily wiped clean.  Of course the surface needs to be glossy, but can be sprayed with dull clear coat afterwards.  But with the gaps already being out of scale wide and deep, IMO making them even more visible would likely not be a best thing to do.  Now if those board gaps were very subtle, bringing them out with a wash might work well.

Although doing a "wash" is a good way to pick out edges and inverted details such as the very thin lines between sheathing, sometimes it's important to be able to effectively clean the top surfaces (as peteski mentions) while leaving the contrasting paint in the crevasses, or the edge corners.

I've found fairly recently, that Tamiya Panel Liner works extremely well for this...it's an enamel and any over-application can be very easily cleaned up using clean paint thinner...making sure the primary paint coats are fully dry/cured before applying and cleaning.

It comes in various colors, and will flow into cracks and low places remarkably, so a lot of higher surface cleaning may be unnecessary.  It comes in five colors...black, brown, dark brown, grey, and light grey.  For my usage, I find that black, brown and grey have worked excellently.

Note that Tamiya posts several cautions about using it, maybe just to cover their butts, but go to the Tamiya site and read up about it.  There are also myriad YouTube videos on its usage.


Cheerio!
Bob Gilmore