Debra’s Fashions of Distinction - Scratch Build Using 3D and Laser

Started by Jim Donovan, November 16, 2023, 10:27:01 PM

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NEMMRRC


Keep It Rusty

Thanks for the update here, Jim. I can see you are definitely putting Tinkercad to the test!

One note: plywood is horrible to cut with a laser. It's the glue in the layers that causes so many issues and will often lead to charred and thick cut lines. I have even tried using "laser grade" ply to no avail. Most manufacturers avoid it completely now. Anyway, just a heads up to save some headaches.

swisstrain

Hi Jim - thanks for starting this post. Very interested to learn more about your journey with these new technologies.

You sure are up for a challenge with this building!

I will follow along.

Jim Donovan

Wow, thank you to all the nice compliments and interest in this project. I have been working towards this one for the past year. When you name the building after your wife you better get it right and I could not think of a better company she would own. Those that know Deb know she loves her clothes and dressing up. When we go on a cruise I better pack a suit and the tux is a given. Deb is the little girl who always loved to dress 'pretty' and she never outgrew it.

Back to the construction. Graig you are right, the laser produces a very dark cut going through 3 mm Baltic Birchwood plywood. It is manageable for two reasons, first it is only three ply keeping the glue issue down and the air assist helps protect the laser opening. More importantly I am using the plywood as a substrate. All surfaces will be covered with 1/32 Monster Modeling brick or hidden by the windows and doors. I doubt anyone making craftsman kits would want to use this plywood but for scratch building it allows for a very strong structure and provides an easy surface to 'hang' other materials on it.

I am essentially making the building from the ground up. Looking at the photo of the real building you can imagine each floor like a shoe box, sitting on top of the floor below. I will use 3D printed columns, brickwork and trim to allow each floor to nest onto the floor below. That is why in the Tinkercad image you see each floor in a different colour, each will be a different design.

Due to file size limitations of Tinkercad I am unable to show a complete 'finished' design of the entire building so I will have to settle with screenshots of the various parts that make up each floor. For the first floor I made a complete replica of the double door entrance found on the prototype building. The hinges and handles will be 3D printed separately so they can be painted as seen and attached to the main part. As this project will include an extensive interior I will need to finish the inside of the doors and windows as well. Inside the enclosed walkway will be two of these:



With the shape of the first floor set I had the laser cut the various walls, floor and ceiling. I used Elmer's Wood glue as I will be gluing sheeting to the walls and don't want water to loosen the joints. The laser took 5 passes moving at 400mm per minute to cut each part out. About 3-5 minutes per part.





In the first photo you see the outer walls are glued to the floor and each other. The eventual ceiling I played with trying some ideas like cutting brick and various colours. There is a lot more work needing to be done before I can make an acceptable brick pattern with the laser but it was worth a try. All will be covered and not seen.

In the second photo you can see the idea I have of an enclosed walkway. This is to allow the ladies of the day to see the fine fashions available inside before entering while keeping them out of the sun or rain. I got this idea from a walking mall we saw in Italy and the idea stuck with me. You may note that 1/32 Monster Modeling 5 row American brick is glued to the plywood substrate. I again used Elmer's Wood Glue. There is very little charring left by the laser and it took only 2 passes at 400mm to cut this thin sheeting, about 1-2 minutes.

More in a minute.

Holland & Odessa Railroad

Jim Donovan

Once the front brick sheet glue had fully dried I decided to use dry chalk pigments rather than staining or painting the brick. I had tested this out on a smaller project and liked the look it produced. I went with a rust red color then highlighted areas with a dark yellow and a brown. At this point here is what it looked like:



I used a clear spray matte varnish to lock the pigment to the brick and protect it. I ended up spraying four coats as the wood just absorbed each like a sponge. When dry I coated the entire surface with sand grout. I used a cosmetic brush to lightly remove the excess. I did this three times to make sure all the crevices between bricks were filled with grout. So here are the two steps:





With the brick coated with grout I lightly spray wet water on the service and then scenic glue.This were having used wood glue is important. Regular white glue will loosen due to the water and the thin sheet will buckle. Even having used wood glue I had a couple of spots try to curl but used clamps to hold the wood in place until dry.

I like the look grout gives the brick. I learned the technique watching a Kathy Millatt  video a couple of years ago and have used it ever since. I am not sure what happened to the photos I took of designing and making the front column work. So I will just end this posting here with a photo of the front so far. Stone columns decorate the brick front. The arches are lined with stone as well. There are several daisy's on each inner arch wall, daisy's being Deb's favorite flower. The columns are based off the prototype photo with an ivy design embossed across the top decorative limestone. Circular decorative vents will go in the squares formed by the horizontal stone work. I wetted the brick lightly and spread super glue on the backside of the decorative stonework before clamping each to the other. Wetting the wood helps ensure a strong bond and resin parts glue best with either epoxy or CA. The columns are intentionally at the height of the top of the models 'floor'. There will be a stone basement that the ground floor will nest into. That is it for now.



/color]
Holland & Odessa Railroad

Keep It Rusty

More fantastic stuff here, Jim. Excited to see this project unfurl. You've got some fantastic results already.

Going forward, give 3mm MDF a shot. It cuts like a dream compared to plywood, offers the same tensile strength (for our purposes), and is often cheaper to buy.

GPdemayo

Amazing Jim, you're scoring points with Deb..... 8) 

I remember the wonderful build of Kathy's layout many years ago on the forum, does anyone know what happened to her?
Gregory P. DeMayo
General Construction Superintendent Emeritus
St. Louis & Denver Railroad
Longwood, FL

bparrish

Did you ever notice how many towns are named after their water towers ! ?

Rollin

Quote from: GPdemayo on November 22, 2023, 07:52:01 AMAmazing Jim, you're scoring points with Deb..... 8)

I remember the wonderful build of Kathy's layout many years ago on the forum, does anyone know what happened to her?

Kathy Millatt was doing some scenery videos for Trains.com, as well as dabbling in Sci-Fi dioramas. Some of her space ship creations are available as 3D prints that are crowd-funded projects.

Pre-pandemic, she was a judge for a British reality show where the contestant teams built railroad layouts in like 2 and a half days. The show was very popular and led to big increase in interest in modeling. I think there may be a link to that show in the older posts?

Jim Donovan

Since my last update I have been designing, printing and cutting additional parts primarily for the interior. The resin 3D printer has had several failed prints so it was time to change the resin tanks's bottom FEP film. The way a liquid resin printer produces an object is there is a UV light panel under the resin tank. The UV panel produces a light pattern that is appropriate for the layer being 'printed'. After a few seconds the resin between the printing plate, which is about .05mm from the bottom is hard, the plate moves up .05mm taking the the now hard shape with it and the process is repeated The floor of the tank consists of a special type of clear plastic (FEP film) which is held in place by interlocking plates screwed together to form a seal that keeps the resin tank watertight. Over time this film gets beat up, scratched and turns cloudy until it no longer allows enough UV light through. When that happens it is time for new film. I mention all this for those that might be interested in a resin printing and offer some tips that can help. I will highlight any tips in red as I go forward. Below you can see the worn old film and what the tank looks like with the new film attached. Film is the only real disposable item on the printer. The manufacturers say the uv light panel is also disposable but it will operate several hundred hours and I have only ever replaced one and that was from me accidentally breaking it.






Tip: The FEP film takes a beating, that is why I spend the extra money for the improved version NFEP. FEP film from Amazon is about $12.00 and the much better NFEP is about $19.00. I have found I can go about six months using the NFEP film and only two months between changes with the old FEP film. Moreover because you need to handle resin carefully the less you need to clean the tank the better.

Another tip, make sure you ONLY use a clean plastic putty knife when attempting to remove stuck dried resin from the film. It can be easily torn or damaged using anything that is sharp or made of metal. Trust me, I know.
Holland & Odessa Railroad

Jim Donovan

While the 3D printer waited for me to fix it I designed interior wall parts and had the laser printer cut them out. The theme for the interior first floor is to be a Victorian European look with wallpapered walls, extensive wood trim,  skirting and lots of paintings. Here is what I came up with:






Holland & Odessa Railroad

Jim Donovan

Lastly, I worked on a method of creating realistic windows, having mullions showing on both sides of real glass. I found it is possible, and as matter of fact the inner framed mullions allow for the cut glass to be put in place, then the frame is put over and glued to the outer window, avoiding glue getting on the glass entirely and presenting a realistic look. However, to accomplish this Clover Glass has to be used. Available directly from cloverhouse.com, it is only .006 of an inch thick (microscope slides are 3-4 times thicker) which works out to about 1/2 inch thick in HO scale, still thick but doable and the glass is exceptionally clear. Since I'm going to the trouble of creating interiors I want big windows that can easily seen through. Here are the first test windows for the back and how they look in place:





Next update I will post detailed CAD drawing of the window so you can better see how the back frame with mullions holds the glass firmly against the outer frame and outer mullion's creating a clean look.
Holland & Odessa Railroad

Keep It Rusty

Jim, I seldom have to change the FEP on my printers. There shouldn't be a reason it gets so "beat up", as you say. My guess is that when a print fails you're draining the resin tank and then scraping out the stuck, failed pieces? If so, this is a sure fire way of hurting your FEP.

Instead, use the printer's "Tank Clean" feature — which cures a very thin layer of resin on the bottom of the tank, which you can remove in one fell swoop by finding only the very corner with your plastic scraper. I don't even drain the tank if I need to do this anymore (including the Tank Clean process itself). This thin layer picks up all the failures, almost like you're getting your leg waxed!

Hope this helps.

GPdemayo

Gregory P. DeMayo
General Construction Superintendent Emeritus
St. Louis & Denver Railroad
Longwood, FL

jerryrbeach

Jim,

Beautiful modeling, love the thought process to enclose the glass in the window frames.  Did you source the wallpaper or design and print it yourself? 
Jerry

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