Sketchup Projects V

June 11, 2026  Conversation with AI Overview:  Curved Glass Distoration vteated with Twilight Render Extension and 3D SketchUp Models

Some earlier SketchUp projects that have been posted includ transparent glass images such as glassware and magnifiy glasses.  After rendering with Twilight Render Extension, the objects viewed through the glass are either distorted or magnified. This is not happening in the physical world but in the digital world.  I've asked AI Overview to explain how this is done.

I asked:

“When 3D Sketchup Models that include transparent curved glass such as a magnifying glass is positioned above a lower 3D object containing text, after it the model id rendered with Twilight Render Extension, that which appears beneath will become magnified from what was really small text before it was rendered.  How is this possible?  It also works with distortions through bottles, etc.”

ThoughtsOfThomasNotNostradamus
Representing Inquiry, Not Opinion

AI Overview said:

The magnification and distortion you see happen because of refraction—the physical bending of light rays as they pass through materials of different densities. Before rendering, SketchUp just displays flat, 2D planes, but once the Twilight Render Extension processes the scene, it calculates realistic light physics based on your glass's properties. [1, 2]

The Science of the Effect

• Index of Refraction (IOR): Twilight Render assigns specific IOR values (typically around \(1.5\) for glass) which dictate how sharply light bends when it enters and exits the shape . [1]

• Curved Geometry: When your model has a convex or concave curve (like a magnifying glass lens or a bottle), the glass acts as an optical lens. It bends the light rays either to converge (focusing) or diverge (spreading), which creates distortion and magnification . [1, 2, 3, 4]

The Unrendered vs. Rendered Difference

• Before Rendering (SketchUp viewport): SketchUp only displays flat, vector-based, or texture-mapped approximations. The lines are straight and unbent, so the text appears at its normal, small size.

• After Rendering (Twilight): The Twilight Render engine simulates rays of light as they trace from the camera, hit the curved glass, and change their trajectory to point at the background text. The result is the optical illusion and magnification you observe.

To adjust the magnification intensity or correct unwanted anomalies, you can often tweak the Architectural Glass settings or manually adjust the IOR in your Twilight Render Extension material templates.

___________________________

Comments:

The Sketch Projects (1) Menu option at the left contains an example of a magnifying glass in the March 26, 2023 post.  One of the  images is shown below.

May 11, 2026  Conversation with AI Overview – Store Front Updates. (Architecture)

I Asked:

“Was aluminum trim on store front windows and doors used in the 1950s or did that come later?”

ThoughtsOfThomasNotNostradamus
Representing Inquiry, Not Opinion

AI Overview said:

Aluminum trim on storefront windows and doors was absolutely used in the 1950s. While it first appeared in the 1930s, aluminum became a dominant, iconic material for commercial storefronts immediately following World War II, continuing through the 1950s. 

Docomomo US +3

1950s Storefront Characteristics

• "Open-Front" Design: The 1950s saw a rise in the "open-front" shop, which featured massive, uninterrupted display windows framed by thin, mill-finished or anodized aluminum.

• Modernity and Maintenance: Aluminum was touted as a "maintenance-free" and modern alternative to wood and steel, appealing to business owners looking to update their storefronts.

• Key Components: Storefronts often featured aluminum trim, entrance doors, and even fixed metal awnings or canopies, particularly on new, modernized buildings or remodeled ones.

• Style: These facades were known for their clean lines, often featuring aluminum-framed windows that were sometimes angled to the sidewalk. 

DAHP (.gov) +4

Why 1950s?

Following World War II, major producers like Alcoa, Reynolds, and Kaiser had increased capacity and pushed aluminum into the building industry. The 1950s represented a peak period for adopting these materials to achieve a sleek, optimistic, "up-to-date" look for businesses. 

____________________________

I Asked:

“In small towns store fronts, window trim and doors did not change much with the times--original doors seemed to last as long as the life of the buildings before they were demolished or some were replaced with updated window glass, frames, and aluminum doors. Does that sound about right?”

That sounds exactly right for the lifecycle of many small-town Main Streets. While modernizers in larger cities often radically updated facades, small-town storefronts typically followed a distinct "stasis and then sudden modernization" pattern. 

Borough of Somerset PA +2

The Lifecycle of Small-Town Storefronts

• Original Longevity: Traditional storefronts from the late 19th to early 20th centuries were built with massive wood or cast-iron components. In smaller towns with less intense commercial competition, these original doors and window frames often lasted 50 to 80 years with simple repainting.

• The "Upper vs. Lower" Divide: You likely noticed that the upper stories of these buildings remained virtually untouched for a century. While the street level eventually faced pressure to modernize, the decorative brickwork and cornices above often stood as they were on day one until the building's end.

•  The 1950s/60s Modernization Push: When changes finally did come, it was usually a complete "system" replacement rather than a gradual shift.

  • • Aluminum "Slipcovers": Old masonry or wood was often covered by aluminum panels or "overcladding" to make the business look up-to-date.

    • The Aluminum Door: These were often the first things replaced because they were lighter and easier to operate than heavy, sagging original wood doors.

    • Glass Upgrades: Single-pane windows were swapped for larger, clearer plate glass held in thin aluminum frames, sometimes angled to draw pedestrians into a recessed entryway. 

San Francisco Planning +10

Preservation and Final Days

In many cases, these mid-century updates are what people remember as "original" because they stayed in place for decades until the building was either restored to its 1890s roots or demolished. The 1950s aluminum frames and doors were so durable that they frequently outlived the businesses they were meant to modernize. 

Department of Archaeology and Historic Preservation (.gov) +3

May 9, 2026 Ghosts on the Prairie -- Railroad Engine Houses

I  remember, back in the 1950s, the old railroad engine house was visible from the baseball diamond near the outskirts of town.  It had two large doors and lots of windows -- mostly broken.  The structure was weather beaten and hadn't been used since the days of the steam locomotives.  A few years later the building had been demolished and all that was left were fragments of the foundation and some junk  which I explored being very inquisitive.

During the past few years, I have scoured the internet looking for old photos of the structure, but came up short.  After researching a few railroad historical sites, it was stated  that engine houses (not roundhouses) were lack luster by comparison and were not very interesting to photograph.  I did find a few images of models that were displayed at the nearby railroad museum that provided a reference for today's project.

Below are images created with SketchUp Make and then rendered with Gemini (front view) based on a submitted SketchUp 2-D graphic image.  In addition, ChatGPT did an excellent job recreating four views  submitted from my SketchUp model. Twilight Render Extension (hobby version) and GIMP were used to create high definition replicas of the 2-D graphics images.  Lastly, the four SketchUp images were "weathered" using GIMP's Hue Chroma option along with increasing the Brightness and Contrast setting.  No SketchUp Viewer model has been posted.  The images are self-explanatory--nothing too technical.

Prompt for the first image:

"Here are four views of a two stall Engine House for  Steam Locomotives, circa 1915.  First, create a front view of this structure that measures 54 feet wide, 76 feet long and approximately 30 feet high.  On top are two brick flews that are used to vent the steam locomotives' smoke near the rear of the building.  In the front are two larger double doors that swing open.  Also, in the front are four parallel lines that identify where the railroad track enters the building,  Please create a photo realistic image of the  building that is shown in a weathered condition and track and ties that are also somewhat weathered.  To the left of the building can be seen a portion of the Wye track that is used to reverse the locomotive's direction.   In the background is flat praire with ripe wheat fields.  There are no large trees.  The sun is shining."

May 1, 2026  Rendering SketchUp Make  Monochrome Images with Gemini AI

SketchUp was used to draw structures originally built in and around 1904.  Here were the prompts that Gemini used to render the images based on the Monochrome SketchUp drawings provided:

Prompt 1:

“Please color and texture the attached 3D drawing of an old building erected in 1904 exactly as it is positioned.  Here are the details to make the image photo realistic and very similar to the original building:  Starting at the top, the shingles are brownish gray slightly weathered cedar shingles.  The frontmost chimney is brown brick with gray mortar.  The back chimney that is near the peak of the roof is circular galvanized pipe with a bit of soot near the top edge.  Since it’s a summer day, no smoke is coming out of either chimney.

The front and side are covered with narrow white shiplap siding with dark green trim along the roof line as well as the window trim. The front door located on the corner is dark wood grain with an old-fashioned brass door pull/handle.  The side door is painted an off-white color and also has a brass door pull/handle.  There is a large sliding door on the side and hinged double doors on the far left end and near the back. The two front four-paned windows are also trimmed with dark green.  Above each four-paned window is a rectangular pane of stained glass with a rough texture that is semi-transparent it is also of a dark green color similar to the trim except it is brighter.

The landscape can be green grass with no trees or other buildings nearby.  The sun is shining.”

Prompt 2:

A second prompt including instructions for trimming out the neighbor's home with similar trim roofing, and siding, etc. rendered it with the same early 20th century appearance.

The rendered Images and original uploaded 2-D images are shown below.

April 29, 2026 SketchUp and Twilight Render Extension -- Laminated Necklace

Today's project is a review activity utilizing Duplicate and Rotate to form a semi-circular arrangement of necklace beads, or in this instance, laminated geometric shapes.  Each layer of the  laminated shape includes the colors red, white, green, yellow, blue,and gold.  The upper semi-circle and corresponding tubular chain was created with the Follow Me Tool using the same path as the rotated shapes (see image below).  

The top half was duplicated, lipped vertically  and joined with the upper half to form the complete necklace.  Twilight Render Extension was used to assign rendering Materials as follows:  Wood-high gloss material for sides of the drawer; Textile-Fabric for the drawer liner; The remaining colors for the necklace were all assign a Reflective Car Paint for each of the colors mentioned above.  No Viewer link is provided today.

________________________

Comment:

Newly added.  A Multi-color bead pattern consisting of circular and elongated beads or cylinders would be easier to draw and definitely more comfortable to wear.  

April 28, 2026 SketchUp Make and ChatGPT -- Six Sided Irregular Polygon

Using the Protractor Tool in SketchUp makes easy work of drawig an irregular polygon.  For me, it was like pulling teeth to get it right usning available text to image AI; however ChatGPT finally got it right after three tries.  Based on my initial prompt shown below, I finally got ChatGPT to draw the shape I request ed after three prompt variations.

The first time, it re-order the specified six angles in the opposite direction.  The second try plotted only 5 sides and ignored one of the angle.  Finally, on the third try ChatGPT got it right, after I specified that the 30 degrees angle needed to be right of the starting 90 degree angle value, instead of above it.  Apparently, it had a conflict with my counter-clockwise directive.

ChaptGPT provided the best irregular polygon by first laying out plotting points and forming the actual shape using degrees values provided in the prompt (see images below).

As for ImageFX and Gemini, after many prompts, they did not perform well (free online versions of all three applications were used).

Below is the ChatGPT rendered irregular polygon and my SketchUp layout for comparison.  Line lengths were not specified that accfounts for a variance in overall shape.  Although the angle values equal 360 degrees, the finished drawing does not completely reflect accurate measurements when measured with a protractor.

April 8, 2026 SketchUp Make & SketchUp Free (Online Version) -- Internal Combustion Motor Parts, Connecting Rods

Today's SketchUp model  shown in Viewer displays grouped parts of a Connecting Rod (Without frills)--not editable within SketchUp Viewer.

___________________________

• Note. The images contained in today's model are for illustration purposes only and are not intended to be used for any real-world application.

April 3, 2026  SketchUp Make -- Pretzel Code

Here is the SketchUp viewer link to the Pretzel Code model  (not editable in Viewer).  The project is in its early stage.  Also. shown below are two Gemini renderings based on submitted pretzel images created with today's model.  The Weld (line) Extension and Follow Me Tool were used to form the initial shape in SketchUp.

Prompt 1 for Gemini:  

"Based on the attached SketchUp image, please create a bowlful of hard pretzels, each approximately 2 inches in size.  Please make the image photo realistic with all pretzels having a shiny surface and lightly sprinkled with rock salt on outer surfaces.  The snack bowl is made of colorful plastic that is sitting on the coffee table of a modern living room. "

Prompt 2 for Gemini:

"Lastly, create a new mage using some of the letters in the attached Pretzel Code image with a lighter background and having better contrast.  Please make each indivdidual pretzel unique with a photo realistic surface and sprinkled with rock salt.  Some pretzel letters have not yet been identified in the cipher. "

___________________________

Note:  The code sender will also be able to take bites out of various pretzel areas to signify a numbers or other special symbols  The advantage of this code is that the sender can eat their mistakes.

March 30, 2026    SketchUp Make -- Organic Images -- Pumpkin

Today's Model required manipulating many surfaces to form an organic image.  I have provided the step-by-step procedure used for drawing everything from scratch.  Several versions were combined to form the final model.  The Viewer file illustrates the details.

• Pumpkin on Box created with SketchUp Make and imported to SketchUp Free (Shown in SketchUp Viewer (not editable in Viewer).

• Rendered images below have minor background, lighting and color adjustments made with GIMP.

__________________________

• Note. The images contained in today's model are for illustration purposes only and are not intended to be used for any real-world application.

ThoughtsOfThomasNotNostradamus

March 23, 2026    SketchUp Make -- One-Inch Diameter Bottom and Tapered (chamfered) Taps 

Today's Model is a follow up on the February 19 post below using a  Five-Helix Thread Design.   The following Tap models were created by Intersecting 4 vertical cylinders with last month's bolt thread.  The outer portions of the intersected cylinders were erased to expose the cutting edges of the tap along with flutes for the cutting oil and clearance for metal shavings.  Additional steps were required for creating the tapered tap model as shown in the images and linked SketchUp file that will open in Viewer.

The tapered version requires intersecting a tapered cylinder and manually trimming off the unwanted surface to form the gradual taper on the first 9 threads (a tedious process requiring the erasure of parts of 9 threads divided into 4 segments (36 segments), with each segment requiring 7 steps to remove excess surfaces and geometry).

The model mimics the actual manufacturing process if turned on a metal lathe.  It would be completed by chucking an appropriate sized end mill and then securing a length of thread extended from a shank in a milling vise metal lathe attachment.

The taper could either be turned or ground.  The final step, not addressed here, would be heating and hardening the tap suitable for cutting through metal.

The completed models are rough approximation of a tapered and bottom taps.  Each has a specific purpose when tapping internal threads inside drilled/bored holes--either drilled completely through the material or blind holes of a prescribed depth (and bolt length) that may require a bottoming tap (see link and images below).

• One-Inch Diameter Taps created with SketchUp Make and imported to SketchUp Free (Shown in SketchUp Viewer (not editable in Viewer).

__________________________

• Note. The images contained in today's model are for illustration purposes only and are not intended to be used for any real-world application.

• Although it is possible to create DIY taps, commercially available taps, if treated properly, will last a long time.
  
  

ThoughtsOfThomasNotNostradamus

March 23, 2026    SketchUp Make -- One-Inch Diameter Bottom and Tapered (chamfered) Taps 

Today's Model is a follow up on the February 19 post below using a  Five-Helix Thread Design.   The following Tap models were created by Intersecting 4 vertical cylinders with last month's bolt thread.  The outer portions of the intersected cylinders were erased to expose the cutting edges of the tap along with flutes for the cutting oil and clearance for metal shavings.  Additional steps were required for creating the tapered tap model as shown in the images and linked SketchUp file that will open in Viewer.

The tapered version requires intersecting a tapered cylinder and manually trimming off the unwanted surface to form the gradual taper on the first 9 threads (a tedious process requiring the erasure of parts of 9 threads divided into 4 segments (36 segments), with each segment requiring 7 steps to remove excess surfaces and geometry).

The model mimics the actual manufacturing process if turned on a metal lathe.  It would be completed by chucking an appropriate sized end mill and then securing a length of thread extended from a shank in a milling vise metal lathe attachment.

The taper could either be turned or ground.  The final step, not addressed here, would be heating and hardening the tap suitable for cutting through metal.

The completed models are rough approximation of a tapered and bottom taps.  Each has a specific purpose when tapping internal threads inside drilled/bored holes--either drilled completely through the material or blind holes of a prescribed depth (and bolt length) that may require a bottoming tap (see link and images below).

• One-Inch Diameter Taps created with SketchUp Make and imported into SketchUp Free (Shown in SketchUp Viewer (not editable in Viewer).

__________________________

• Note. The images contained in today's model are for illustration purposes only and are not intended to be used for any real-world application.

• Although it is possible to create DIY taps, commercially available taps, if treated properly, will last a long time.
  
  

ThoughtsOfThomasNotNostradamus

February 19, 2026    SketchUp Make -- Thread Review Methods

I have attached a link to SketchUp viewer that illustrates two methods for manually creating bolt threads:  Thread Segment Method and Five-Helix Method.  Both methods have been illustrated dozens of times before, but in order to stay sharp, a run through now and then prevents the cob webs from forming.

Thread Design Methods with SketchUp Make or SketchUp Free  (Shown in SketchUp Viewer (not editable in Viewer).

__________________________

Note. The images contained in today's model are for illustration purposes only and are not intended to be used for any real-world application.

ThoughtsOfThomasNotNostradamus

December 22, 2025    3-D Dragon Ship -- SketchUp Make, ChatGPT, GIMP

A crude SketchUp 3D model (skp file) of a Viking Ship along with a prompt for ChatGPT was all it took to create this elegant rendering shown below.  GIMP was used to edit out a few unwanted elements above the mast and to provide a texture background on one of the examples.  ChatGPT now provides multiple views of a 3D model upon request.

Today's prompt for ChatGPT was worded "Please create an equisite and stylized Viking Ship with a serpent-like figure head and a tail.  Include a wooden mast, oars, and colorful sail along with other embellishments that would be authentic for this type of artwork."

Here are two images that have been edited slightly with GIMP:

December 14, 2025    Camera Animation Revisited -- SketchUp Make, GIMP, Gemini, and ChatGPT 

Today's post goes back to 2014 to take another look at a gif animation created with images from a SketchUp Model and then layered with GIMP's animation feature.  

Gemini and ChatGPT both generated polished still-image renderings with a pleasant background--but not a looping animation as shown below,  Here is the original functioning animation created with GIMP . . .

________________________

Comments:

Since neither ChatGPT nor Gemini (free versions) delivered a revised animation containing a new background and  enhanced finishes on the camera's surface, I revised the background myself with GIMP.  The enhanced finishes will have to wait for another day.

• For this project, I used 10 key frames  that had to be cropped from the original GIMP animation sequence that was opened with GIMP.  After pasting the cropped portion of each key frame onto the "front yard"  background image, all ten combined jpeg images were later opened as a layer in a new GIMP file that would later be saved as a  GIMP animated  gif file

• Instead of using 65 separate frames  all having  a 100ms duration like in the original, I opted to use only ten frames with variable frame lengths (durations).  For example, Frame 2 was 1800ms at the beginning, while Frame 7 (the combined camera flash, button and lens shutter movements was only 100ms  (a tenth of a second).  The other key frames also were assignet variable durations. 

• This method works fine for simple animations such as this.  Even with only ten frames to process, it is a tedious process.  The  Gif Animation Export  option, allows  GIMP to process the specified  duration of each  frame rather than to have a blanket setting of 100ms, for example, for the entire animation sequence. 

• Another advantage of using these steps is that no dedicated background image is required for Frame One.  The method described above  has the background merged with each of the 10 frames.  What I have described is an old-fashioned, straight forward process that bypasses many of the built-in features that are more suitable for advanced GIMP users. 

• If you would like to compare  the layers for both the Orginal using 65 layers and today's revised version using 10 layers (frames), they can be download here:

Original Animation  (4.6 MB |   Revised Animation  (2.72 MB).

• The version running below has been optimized by removing the bloat with EZGIF.  The gif animation is now only 345 KB.  The image quality  remains about the same--I can't notice any differences.

• Lastly, here is a similar version of the updated animation converted from Gif to MP4 using the EZGif online app.  Click here to open or to download:   Front Yard Camera.Mp4 (2.21 MB looping 10x).
  
  

ThoughtsOfThomasNotNostradamus

December 13, 2025    Lemonade Glasses Revisited -- SketchUp Make and Gemini 

The Lemonade Glass renderings created with Gemini today were originally modeled with SketchUp Make (see the March 15, 2023 post located in SketchUp Projects I) .  At that time, Twilight Render Extension for SketchUp Make (Hobby Version) was used to create the rendered version.  I liked the final outcome but was a bit disappointed with the blurry yellow band that I was unable to render more clearly (see images below).

Today, Gemini was the tool of choice to correct the earlier project's flaw.  The images and descriptions beneath each picture shown below will explain more.

I was so pleased with Gemini's greatly improved image that I returned this comment:   I wrote, "Perfect! It looks just like Grandma's kitchen."

With that, Gemini sent another, even more refined image, with a centered decorative place mat on the table, lace curtains for the window, and a detailed teapot on the shelf.  It pays to praise a job well done--even when conversing with AI. 

_____________________

Comments:

It should be noted that Twilight Render Extension renders the framed area of the 3D model whereas Gemini works only from an uploaded 2D image based on the user's instructions.  Whatever goes on behind the scenes regarding the processing of photorealistic images and colors remains a mystery to me.

ThoughtsOfThomasNotNostradamus

December 12, 2025   Glass Vase Revisited -- SketchUp Make and Gemini 

The vase used today was originally drawn for earlier models that were posted in SketchUp Projects IV on October 4th & 6th.

The design was an intricate assembly of partially opaque spiral grooves that were first formed using welded spirals comprised of deformed helixes (see October 4 Model).  After the model was completed, it was turned over to Gemini AI to add a floral arrangement and to render the cut glass.

Today's project started with the basic spiral-shaped vase--a 2D jpeg image.  Slightly different instructions were applied for today's project and once again, Gemini did an outstanding job.  A closeup view is included that shows a blown-glass effect within the glass.

Refer to the other images for the instructions that were provided.

ThoughtsOfThomasNotNostradamus

December 5, 2025   Drawing Triple Lead Screw Bolts -- SketchUp Make and Twilight Render Extension

Today's project was created using the Thread Segment Method.   When compared to the Helix Method, especially for three sets of threads (triple lead screw), the work load is about the same--very tedious when drawn from scratch.

If speed is your goal, use a thread making extension; however, a more satisfying approach is to draw them manually--an affirmation of your acquired skills.

Here is the link to the model that is accessible with SketchUp Viewer:  Triple Lead Screw Bolts (Opens in  your browser, Uneditable).   It provides most of the steps for creating the bolts (except for one that was accidently overwritten--merging the upper chamfer with the thread).

_________________________

Note. The images are for illustration purposes only and are not intended to be used for any real-world application.

ThoughtsOfThomasNotNostradamus

October 30, 2025 Drawing Gears -- Gear Reduction with SketchUp Make

Today's Model provides an illustration for drawing gears.  For actual use, gears will require more engineering regarding proper mesh alignment and design.

The two- and three-gear configurations shown below can do several things.

• Two gears of equal size can change direction.

• Adding a smaller diameter third gear will increase the shaft speed of the smaller gear when meshed with either of the larger (drive) gears.

• If the drive gear is the smaller diameter gear, meshing the larger gear will decrease the shaft speed of the larger diameter gear when compared to that of the smaller gear.

Drawing the gears requires that the cogs on both the larger gear are the same size.  In this project the smaller gear has a diameter that is one-half  that of the larger gear.

Since using 24 line segments in the large and small circles for each gear is easy to work with,  the large gear has 24 cogs with 1 cog assigned to each segment. The smaller gear has 1 cog assigned to every two line segments in its circle.

The gear ratio is therefore two to one, or 24 cogs and 12 cogs.  That is, the gear ratio refers to the number of revolutions of the shafts. Simply put, the smaller gear will rotate twice for every single revolution of the meshed larger gear in this instance; or stated in reverse, the larger gear will rotate once for every two rotations of the smaller gear.

A basic layout design was used to draw and form the first cog, after which the single cog was grouped, duplicated and rotated into position for the remaining cogs.

Click on Gears for Viewer to see the 3D model containing each step for drawing the gears (will open in your browser--Uneditable.  Note, last month Trimble informed its users that Viewer was no longer compatible with Android devices).

_________________________

Note. This model is for illustration purposes only and is not intended to be used for any real-world application. 

ThoughtsOfThomasNotNostradamus

October 12, 2025 Bolt Thread Design and Scaling -- Linear Interpolation

For the past several years, deforming/scaling bolt threads using a highly accurate method of alignment has been shared many time on this website.  However, I believe the method that I devised by trial and error, actually has a name in the mathematical sense--Linear Interpolation. 

Some of the YouTube videos explaining the function of Linear Interpolation resemble the layout I've been using.  An attempt has been made to label the variables according to the x, y graphs shown in the videos.

Helical thread design in SketchUp 3D drawings require coordinates to be entered into the Measurements Box for accurate shaping, angles, and dimensions. These values would either be taken from a reference table of thread specifications or mathematically derived. Today's discussion and illustrations explain how this process can be bypassed through the use of a simple template(s).

Since my system does not require values, all that is needed is to have the correct proportions when laying out the thread profile in relation to the diameter of the bolt thread.  See images below.  When finished, the bolt can be scaled to a 1" diameter, provided all proportions for that size bolt have been maintained, without affecting the 60 degrees flank angle (2 x 30) or thread depth.

The key to accuracy for creating a thread profile is the use of the Protractor Tool that is rotated 30 degrees at the top and bottom corners of the Thread Crest.

• Then the Thread Depth is established using the Inference feature by moving the Pencil Tool horizontally without drawing a line to the left from the tiny root marking(s) on the face of the thread profile until  the pencil comes in contact with the broken protractor lines representing the flank(s).  Today's Thread Profile is drawn for a 5-helix thread requiring an upper and lower root segment.  (Another option is to use a 4-helix design/profile requiring only 1 root segment at the bottom, doubled in size.)

• After each intersection point is identified, lines are extended/angled upwards and downwards from the left--root areas--on the bottom and top of the crest's nose following the protractor tool broken lines (each at a 30 degrees slope).  A vertical line is drawn at the thread depth for clarity as shown below.

I have also included the SketchUp model, Linear Interpolation for Viewer that shows the graphic layout from  all angles.  There is no thread creation today--you can look at previous posts to see where the graphics/template(s) areas temporarily reside in the bolt models (Hint, they're near the bottom of the bolt threads).

Lastly, not being a math whiz, I cannot verify the accuracy of my observations.  You'd first need to measure x and y values with a high degree of accuracy and apply them to an equation that solves for X where x is a pair of coordinates on the "corner" where x(2) meets y(2) on the minor diameter.

_________________________

Comments:

Thread Deformation and scaling occurs at the end of the thread drawing process.  Before that occurs,  Thread Profile design as well as Helix  construction, scaling, duplication and alignment are preliminary steps that must be completed error free. That value depends on the accuracy of the Thread Profile's Thread Depth for the 1" diameter bolt.

ThoughtsOfThomasNotNostradamus

October 8, 2025 Draw Your Dream Home -- LInes, Rectangles, Inset and Push/Pull

Yes, this is all you need to use in SketchUp and with Gemini AI you can create your personal palace.  Here's How:

Prompt:

Instruction for Gemini:   (lengthy description)

"Attached are six drawings of a southwestern style home.  Please create a detailed photo realistic drawing of the back view of the home only as shown in the Stucco House 004 drawing.  I will edit my instructions for the other angles later.

Here are some of the specific details to include:  Stucco exterior painted with a light “Baked Potato” Brown. Garage doors can be a matching color.  The front entrance doors have brass door pulls both positioned below center of the 8 ft. tall doors to the inside of each door  The  doors are varnished, light grained wood with some of the grain showing. Above the front entrance doors is a lightly tinted window.  All other windows are also lightly tinted.

There is a concrete driveway and a sidewalk on one side leading to the back of the home.  In the back yard is an in-ground swimming pool located in a surrounding concrete patio.  The back of the home has an overhanging patio that is part of the main structure and two pairs of sliding glass doors that are also tinted.

The home should have a desert landscape with a few desert shrubs.  Lawn furniture, an outdoor grill, and other accessories can also be added in the back yard.  A matching cinder block privacy fence can be added to the back yard only if it does not block the view of the home and yard.  The Sun is shining."

SketchUp Drawings for today's project:

Here is the SketchUp model of the proposed home.  It is simple line modeling that can be done by a person new to SketchUp:   Stucco House for Viewer (will open in your browser, uneditable).  Six scenes have also been identified  in the viewer model.

Below are the six images that were uploaded to Gemini.  Three of the six scenes originally uploaded to Gemini rendered properly. Gemini confused my instructions until the specific image was identified to be generated.  In this instance, Stucco House drawings 001, 004, and 005 were completed exactly as specified.

Gemini had difficulty translating the instructions for images 002 and 003 -- 006 I did not try.  The instructions above, shown in italics, were edited to correspond with the name of the drawing to be used.  That is, Stucco House 001, 002,  003,  004, and 005 and related scene descriptions.

Even after trying several versions of directions, Gemini incorrectly juxtaposed elements for scenes 002 and 003 (shown below).  Without initially uploading all six views at once, I surmised that Gemini would not create a logical transition from one view to the next.  When an image did not generate the way I wanted, I rephrased the italicized portion (see instructions above) until I got accurate results.

Below are the before and after images that turned out very good and also two that didn't.  For example, the swimming pool was placed in the front yard facing the street and front entrance.  Another generated image had part of the front windows in line with the back of the house.

Lastly, you will notice I've also added a few nature scenes, holiday decorations, and preparations for golf, going shopping, or a day at the office.

ThoughtsOfThomasNotNostradamus

October 7, 2025 Welcome to SketchUp Projects V -- Newest Projects awaiting Inspiration

SketchUp Projects IV had exceeded its capacity and  it was time for an update.  So here we are, ten months later, ready  to begin filling SketchUp Projects V  with all sorts of projects yet to be imagined . . . .

ThoughtsOfThomasNotNostradamus