SketchUp Projects

November 28, 2021 Scaling a Model--SketchUp. This post explains another way to set up a simple bolt thread. I started with a 48 foot diameter and eventually scaled it down to a 1 inch diameter x 2 inch length of thread. The reduction of size was 576 to 1.

After the section of thread was completed and grouped as a single object, I applied the Scale Tool. Scaling diagonally about center I entered .0017361111111 SketchUp's Measurements Box. I'm unsure of how many digits beyond the decimal point were significant but the final cylindrical result measured 1" x 2".

Here is the downloadable SketchUp file (requires SketchUp to open): Scaled Down Bolt Thread. skp. The file contains a detailed step by step walk through for completing a thread profile, thread segment, thread spiral, and a section of thread.

I had not used the process explained in the initial set up of ratios between diameter and height before. It's very straightforward--simple math.

In the past, I had used the equivalent of a 48'diameter/ (1" circle segment length from the circumference (circle contains 24 default line segments connecting at a 15 Degree angle to form a 360 Degrees circle) as the distance between thread crests in the thread profile. I had also used 1/24 the of that length to elevate the slope for each segment. Although the thread spirals aligned nicely, there was no initial calculation for distance between thread crests (tpi). Vertical scaling had to be used to obtain the proper thread count which was flawed by thread angle variations caused by + or - 36 Degrees depending on the direction of scaling required (to stretch or compress).

Today, I used 1/12 of the diameter (4 ft. as the thread Height (eventually scaled down to 12 tpi). I then used 1/24 of 4 feet, or 2 inches, to elevate the slope for each segment. Crest height was predetermine for accurate tpi (threads per inch) count. Crest angle remained constant (proportionate) when diagonal scaling threads to size.

This is explained in the SketchUp File linked above. Also new, I found scaling down from a 48 foot diameter to one inch easier than I had expected.

The creation of of thread segments and spirals followed the same techniques I'd posted many times over the years. The finished 1 inch model adjacent to its 48' big brother was difficult to zoom to so I copied and pasted it to a separate file. The image below was exported from there. Had I hidden everything but "Shorty", it may have been more accessible.

Lastly, I try to avoid entering calculated line lengths in the Measurements box. Instead, if possible, use the divide tool on a line from a previous step in the model.

The next example was drawn to scale (1:1) with no need to scale down. This example may seem contradictory, but depending on the model's layout or complexity, scaling 1:1 may get the job done.

Image 2 below is another 1 x 2" length of thread, but this time it is 8 tpi (SAE coarse). I had difficulty trying to scale this model down from very large dimensions--it was always ended up 1/16th inch too long or too short. In my fourth try I used 1" for the diameter and 2" for 16 threads--it was faster and more accurate.

I used the divide tool to obtain 1/24 of .125" for 8 tpi (distance between thread crests)-- the existing existing vertical line from the previous step. The 1/24th line segment was then duplicated and moved into position. Had I elected to calculate the 1/24th with a calculator, the decimal fraction would have been 0.00520833333333. For accuracy sake, its best to let Sketchup divide line segments and avoid manually entering decimal fractions manually. For this model, either way works, but using the calculator and drawing the line from scratch is another couple steps that can easily be completed by: dividing 1/8" vertical line by 24, selecting 1 segment, moving it into position, and connecting the top of it to the point of origin with a diagonal line to form the slope. Here's the related SketchUp Model: One Inch diameter 8 tpi Thread Drawn to Scale (requires SketchUp to open). If you do it, you'll see what I mean.

October 17, 2021 Rendering Images Update--SketchUp Make, Blender, and Gimp. Here's my third rendered image using Blender. I have posted before and after images (see below), the related SketchUp File (requires SketchUp to open), the Collada 3D resource file (with a dae extension) , and the Blender file (requires Blender to open). Gimp was used to edit background and for minor touchup on shadows.

The process went better after I realized the interior colors had to matched the exterior colors. Drill bits similar to these were posted in August on the Home page.

The next step was to apply materials, however memory requirements of Blender Version 2.93 exceeded my 11-year old computer's Ram and Graphic Card capabilities. Every time vector nodes were added and linked to Blender's Shader, materials would turn Pink. A number of other causes could be the problem, but I suspect its insufficient Ram or improper setup on my part.

To add more visual effects, the last six images below were further modified with GIMP where a number of more straight forward color and gradient schemes were applied. It's not quite the textures and gleam I was hoping for, but it will have to do for now.

October 16, 2021 Rendering Images--SketchUp Make, Blender, and Gimp. Even before I began using the free version of SketchUp, I had dabbled with the animation features of Blender. Back then, my computer and internet connection did not support YouTube videos. Today, online tutorials from YouTube makes Blender easier to learn. The following is a brief description and a couple images I recently rendered with Blender.

Besides video-like animation, Blender can also be used to render still images from models created with SketchUp Make or SketchUp 2017 (free version). To do so, the model needs to be exported from SketchUp as a "3D Model" using the Collada option. The SketchUp models used today were included in previous posts on this website. They will now be exported as 3D files with ".dae" extensions.

After opening Blender, the Collada files can be imported for high-quality rendering. (High quality rendering is not available in SketchUp's free versions.) By the way, Blender is shareware that has been compiled by many contributors over the years.

It was a struggle at first to navigate Blender, however, this particular YouTube tutorial helped immensely for my intended purpose: Rendering a SketchUp Model in BLENDER! Quick and Easy...

Here are personal comments for my first two attempts at rendering with Blender:

• In the first image (see below), the vertical screw had diffused lighting/noise on the underside of each thread. I think a secondary light source from the front would brighten the shaded threads. Other Blender settings may address the noise issue once I find locate them.

• In the second image, I had difficulty positioning the camera and as a result part of the metal ring on the left end of the pocket knife had to be manually drawn in later with GIMP--sorry about that. I also erased the surface shadows that did not contribute to the image's overall appearance.

• Viewing close up, it appears that shine, or luster, is created during the rendering process by interspersing various levels of white pixels giving the illusion of depth and curvature. Along with shadows from a light source and camera angle, each object's appearance is improved. As a beginner, clumsy navigation is my biggest obstacle (practice makes perfect).

• Gimp was used to edit background and for minor touchup on shadows.

• These renderings are still a bit dull. I haven't mastered the use of lighting and camera position. Realizing Blender's full potential is yet to come.

With practice I hope to have most of my renderings gleaming, glowing, and more photo realistic.

October 12, 2021 Drawing Phillips Head Screws--SketchUp. I have avoided drawing Phillips head screws in the past because they looked too complicated. By taking a closer look at a few screws it wasn't too difficult to draw a suitable likeness--at least for illustrative purposes. Technically, however, today's models and rendered images don't match up with any Phillips screwdriver.

Below are a few images rendered from today's downloadable SketchUp Model: Phillips Head Screws (requires SketchUp to open). The Interior shape of the Phillips head was drawn first and then grouped, and inserted into Round and Flat Screws.

Another SketchUp model presented today illustrates a segmented technique for drawing threads using an arbitrary distance for the thread pitch. The slope of each segment of thread (where there are 24 segments per thread) is tilted 1/24th of the pitch instead of building one thread from a helix and cylinder: Coarse Flat Head Phillips Screws (requires SketchUp to open).

The models I drew used no precise dimensions and probably would not work well with a Phillips screw driver. With more patience, exact measurements could have been taken from the end of a screwdriver and Phillips Head screw. It would seem pointless to do this because screwdrivers and screws are readily available almost anywhere.

Also, I did not clean up the internal geometry of the screws that would need to be done if intended for 3D printing. For 3D modeling, it is good practice to remove all unneeded entities and fill any voids. But, for external 2D imagery shown below, internal imperfections will not usually affect the appearance.

The last image in the series shows the grouped Phillips Head being inserted into a coarse thread screw. Instead of positioning the grouped section after it is drawn, it may be easier to draw it in place while keeping the rest of the screw hidden--then unhide it when finished.

September 30, 2021 Three Blade Pocket Knife Drawing--SketchUp. The following SketchUp model shows the body of a pockect knife and three blades--actually, two blades and a screwdriver. Traditionally the screwdriver would also have a bottle cap opener cut into it, but I totally forgot about it until now.

This is not an accurate drawing showing the mechanics of how a jackknife opens and locks while cutting. The downloadable SketchUp model is linked Here: Pocket Knife. (requires SketchUp to open).

Below are a six images rendered from the SketchUp model. Images 5 and 6 were edited with GIMP. Image 6 contains a Bottle Opener added to the screwdriver later. It was drawn with GIMP and does not appear in the model.

September 28, 2021 Two Inch PVC Pipe with Tapered Threads--SketchUp. PVC pipe has replaced some of the metal pipes used in the past. As far as sizes are concerned, PVC and similar synthetic products used for plumbing conform in most ways to their metal counterparts regard pipe sizes. The inside measurement of pipe determines flow rate. There are striking differences, however, regarding tightening screw components compared to metal. (No huge Pipe Wrenches that we used in the past to crank screwed connections to their breaking point; no solder or plumber's tape is necessary , for example). The Tapered Thread usually seals with a hand tightening plus a few more turns depending on the size and tensile strength of the material. Twist it too far and it, too, will split.

Being a beginner with pipe terminology, I used the wrong diameter for yesterday's tapered thread project. I incorrectly used the 2" diameter for the outside measurement. For this size pipe, it should be 2" for the inside and 2.375" for the outside. Also, I used 1.75 degrees for the thread taper. Yesterday, I used a few hundredths of a degree more than that. Depending on the source or chart, both appear to be within an acceptable range. Everything else was drawn using similar steps.

Here is my downloadable SketchUp model which requires the SketchUp application to open: Two-Inch Tapered PVC External Pipe Thread. Below are seven images rendered from today's model.

September 27, 2021 Tapered Pipe Thread--SketchUp. It took 3 tries to finish a 2" length of tapered external thread. It required juggling 13,248 individual line segments in order to get a section of 23 threads. The specs for this size pipe (2 inch diameter) required 23 external threads for 2 inches (11 1/2 TPI). The first two attempts were unsuccessful because I was in a hurry. Take a look at today's model and you'll get an idea of the accuracy required. I listed the steps in usual fashion.

Note that it was not perfect. Threads nearer the top of the pipe vary in thread angle from approximately 1/2 degree to as much 2 where a 60 degrees angle is ideal between flanks (V groove). I speculate a larger tolerance would be required. Here's the Link to my SketchUp model: Two Inch Diameter Tapered Thread (requires SketchUp to open). Three images rendered from the model are shown below.

Here's a related YouTube Video for making home repairs: How to Thread Pipe; A Beginner's Tool by seejanedrill (Leah Bolden). This is a bit off the subject but among many other videos she has presented that I've watched multiple times include: Ticking Stick, a Carpentry Hack (that few people know, Why is a Carpenter's Pencil Flat? And Other Stuff, and Life Hack: 4 helpful ways to use a tape measure.

September 25, 2021 Thread Drawing Preference--SketchUp. For quite some time I've preferred using a thread profile and wire frame design. I find that scaling a helix on a cylinder is okay for basic thread desgin, but seems to be limited for more complex thread profiles. Today's drawing and related SketchUp model follow a layout I found at Theoretical Machinist.com. Here's the link to a thread calculator, images, and glossary of terms I used as a guide: Thread Calculator - images and Glossary. Screw thread Images link on Google: Screw Thread Terminology.

The link to my downloadable SketchUp model is: UnC 1-8 Thread (requires SketchUp to open). I attempted to be more diligent getting the shape right than I've been in the past. Someday I hope to reproduce this or a similar 3D model on a 3D printer. I don't have our 1/2 ton lathe anymore and I'm waiting for the consumer grade 3D printer industry to get out of the "Erector Set" and "Accessorizing" marketing strategy before buying one. I expect a printer to be durable, assembled, complete, and ready to print out of the box like most other printers.

Lastly, there are some excellent YouTube videos explaining threads. Here are two links: Thread Measuring--3 Wire Method and Three Ways to Measure Threads.

September 23, 2021 Troublesome Alignments and Selection While Drawing Cone Spirals--SketchUp. Today's post is intended for SketchUp users. There is no room for error when drawing the September 22 model with SketchUp 17 (free). It is very satisfying to get it right on the first try--which normally doesn't happen for me. Through trial and error I have discovered a few tricks that seem to work. I'll attempt to explain some of these subtleties today.

1. Conical Helix Construction. There are YouTube Videos that show how to draw a conical spiral from scratch. The point of the helix is not completed, however, and does not show creating a conical thread as drawn in my model. In the video I viewed (there may be more I didn't find) the spiral terminates on another circle near the apex. My models terminate at at the end of a predetermined height at the end of the center vertical axis. (YouTube Resource Link: Cone spiral in Sketchup contains almost the same steps that I use.)

Initially, I found that shifting (pushing) horizontal helix lines into diagonal position also moved the center vertical axis line off its axis at the top and altered the height. To remedy this I erased the topmost right line that touches the tip of the center vertical axis. Now, after the helix lines are shifted upward, the line from beneath the deleted one fills in the void and ends/terminates at the top position. The vertical axis will remain plum. Problem solved. See the first 4 images below. Also refer to the Sept. 22 Model below (requires SketchUp to view. Remember to zoom in to see what's going on near the top of the spirals).

2. Choose the helix strand that originates on the red axis. Usually, the method for selecting a cylindrical spiral strand from among 23 others is to simply triple click it. In this case, all 24 conical helix strands connect at the top. Solution: Select Parallel Projection Camera setting. Select Top View. Zoom in over the cone-shaped strands. Zoom way in until the last segment of all 24 strands are clearly in view (See the last 3 images below). At this magnification, the red axis should be clearly visible.
   Choose the strand that runs along the red axis. Erase the single line segment that touches the center axis. Next, triple click on the remaining portion of the strand that originates at the red axis and copy it. Then, select all of the remaining strands and erase them, but leave the vertical center axis untouched. Finally paste the copied spiral strand using Paste in Place. Use the line tool (pencil), connect the end of the pasted strand to the top of the center axis line. Problem fixed. (Other procedures will accomplish this task as well).

3. Other Trouble Spots. Almost every step of drawing this model presented problems. Drawing and then Shifting 120 horizonal lines to begin with required some practice. Dividing the hypotenuse by 120 and then Moving and Duplicating 119 segments upward will make 5 spirals (5 tpered screw threads). The math for this was (5 threads x 24 line segments forming the circle at the base = 120). This assumes that a 24 segment circle is drawn for the base of the cone/spiral.

4. Clean up is tedious, that is, erasing excess line fragments. Zoom in as needed. Also erase the outer circle at the base before attempting to shift all 120 horizontal lines into diagonal position. These lines will have a gradually steeper slope the closer you get to the top of the cone. Every sloped line increments as the spiral ascends to the top. You can't copy the first angle at the base upward to the top--that doesn't work for conical spirals.
   Additionally, with a cone shape, the slope increases with every upward shifting line segment, because the cone shape narrows near the top while spacing of 120 lines along the hypotenuse remains the same. All diagonal lines get stretched at an increasing rate.

5. Once the 120 diagonal lines are aligned, trim off the lines on both ends but be careful not to erase the top most diagonal segment. The left line and diagonal slope line appear to have the same slope at the topmost point.

6. Next, the 120 diagonal slope lines need to be duplicated and rotated 15 degrees, 23 more times (24 x 15 = 360 degrees).
   The next items discuss using the conical spiral for making a five-thread wood screw:

7. Draw a cone over the Grouped conical spiral. Use the Follow Me Tool to works best in my opinion.

8. Check for accuracy. If there are gaps between the spiral and the cone surface. Try again. There may be issues at the top or at the point of origin where the conical strand touches the circular base. All contact points have to be connected in the conical spiral.

9. Forming The Thread: Duplicate and Rotate the spiral inside the cone 180 Degrees Clockwise. Explode 1 copy first. Then select the the second and explode it. (Don't click on the model quite yet.) Select the scale Tool to reshape the exploded and select spiral. Grab and handles while in the mid position at the corners while holding down the Control Key (Windows). Move inward from center until a symmetrical wood screw thread is formed. Press undo and try again if the first try was unsuccessful.

10. Add a head to the wood screw. The fun part.

September 22, 2021 Groups Vs Components--SketchUp. Using SketchUp's Groups and Components are two methods of keeping objects in a model separate from other entities. The finished version of the model can also be a group or component.

Groups and components seem similar at first glance, but in fact, they have specific uses that make simple and complex models manageable. Most of my models are for illustration. Grouping objects during layout is predominately my preferred option. I'm just going to touch on a few basic uses of groups and components.

In the images below, the model was drawn using grouped entities. When finished I grouped the model. I also duplicated it once and converted the copy to a component. Next, the component model was duplicated times 5 times since my illustration was to contain 6 wood screws. Downloadable SketchUp Model: Review of Cone Spiral and Screws (requires SketchUp to view).

As I continued working, six screws were arranged in a random pattern. Once satisfied with the layout, I tinkered with the screw color and cleaned up a few extraneous lines. Since I was editing a component, I only had to make changes once, instead of having to repeat the steps for each copy.

Storage and Memory: Grouping objects can waste memory if many duplicates of the same group are made. If a component is created instead of a group, duplicates can be created as Instances that require only entities info of the original model for the entire lot.

For example, if 100 instances of a Component are created, it requires much less memory and disk/cloud storage than duplicating a Group an equal number. Another advantage of creating components alluded to in paragraph 4 above is the option to make changes to the component and have all edits automatically applied to its instances. Duplicated groups, however, require changes to be made individually on every copy which can be time consuming. Also note that Components can be made Unique to prevent them from changing when revisions on other instances are needed.

Grouping is convenient when drawing entities that need to be "fit" into position. Grouping objects prevents "sticking" that can occur when ungrouped entities come in contact with each other when being moved--usually during alignment. Groups do not stick. Neither do components, but in today's application, I thought groups would be more convenient.

September 21, 2021 Comparison of Coarse and Fine Threads--SketchUp. This post compares one-inch diameter bolts. The SketchUp Model contains a length of coarse thread next to an equal length of fine thread. The coarse thread, as its name implies, has 8 threads per inch, while the fine thread has 12. This model was drawn to scale using UNC and UNF specifications for a 1" inch diameter bolt. A 60 degrees V-shape thread style was chosen for the thread profile. It's easy to draw if the protractor tool is used to layout the thread angle.

Here is the link to the related downloadable SketchUp model: Coarse and Fine Thread Comparison (requires SketchUp to view). Hopefully, the linked drawings are accurate, but they may need tweaking to work in a real-world application. I'm no expert.

September 19, 2021 Drawing Threads to Scale--SketchUp. The following is a SketchUp model and image that were drawn to scale. When drawing small objects it can be more difficult than using magnified dimensions. Pixels on the screen can only be enlarged so much before they become crowded and/or unresponsive. That is why I prefer to work with feet rather than decimal fractions of inches.

Today's post again reinforces the idea that it's sometimes better to duplicate fractions of lines rather than to rely on dimensions output in the measurement box due to rounding.

For today's model I have chosen a 1/2" coarse bolt thread with 13 threads per inch, a thread angle of 60 Degrees, and a simple V thread design. Only the thread was completed. Here is a link to the downloadable SketchUp model (requires SketchUp to open): Coarse Threads for Half Inch Bolt Drawn to Scale. There are a few more explanatory comments than usual.

Here are two YouTube links showing other ways to draw threads. The first video uses scaled up metric dimensions for greater precision that applies ANSI specifications: How to make ANSI Threads in Sketchup. The instructions produce a nice looking thread, however the thread angle is more like 85 degrees instead of 60 degrees which appears to be a customization. The math quoted corresponded with what I got when following the video. The second video demonstrates another method for drawing the helix and scaling the minor thread diameter (thread root) of an external thread: Detailed tutorial on how to draw bolts and nuts in Sketchup. I like the method of scaling/pushing the Minor Diameter into position rather than using the Measurements Box. Both videos required access to specs to follow, online thread calculator, or a knowledge of applied thread formulas.

Taps and Dies have made life much easier. So has the Hardware Store!
We don't have to re-invent the wheel each time a simple screw , bolt, or fastener is required.

September 18, 2021 Assorted Thread Styles--SketchUp. Today's post illustrates another variation in drawing threads with SketchUp. Square Threads are shown on a shaft with splines on both ends. Three images from this model can be viewed below.

The SketchUp Model can be downloaded by clicking this link: Square Threaded Shaft with Splines (requires SketchUp to view).

The model also shows how the diameter of the completed thread spiral can be trimmed down by 50% using the Intersection Tool. It may have been easier to start over with a new thread profile with a more shallow square thread.

September 15, 2021 Drawing Chamfers for a Bolt, Continued--SketchUp. This is another presentation showing how I create a SketchUp model for chamfered bolts. Included are several images and a link to the downloadable SketchUp Model: Chamfers for Bolts (requires SketchUp to view.

Besides using Intersection for the the lower 3 three chamfers, I have used the Contours Tool to fill in rounded corners on the Hex Bolt's head (select the top half of the head of the bolt and click Contours). Contours create a component on the top which needs to be exploded before doing a bit of touch up inside the upper circle. That is, unwanted connecting lines within the topmost circle should be erased. Similarly, internal and external geometry on the thread intersections require cleanup by erasing unnecessary lines leftover from the intersections.

For another perspective I have drawn similar bolts, this time starting with the top and finishing with the thread intersection at the bottom. If you open the SketchUp model, you might want to flip the view upside down midway through the illustrations. It can be downloaded by clicking this link: Top down Build for Bolt. Three images from this model can be viewed below.

September 13, 2021 A New Page for SketchUp Projects--T. Bolton Digital Art. My home page is filling up. It's time to make use of another page to hold future SketchUp posts--SketchUp projects including rendered images or videos, links to the related SketchUp models I have created, and links to helpful resources found on the internet (YouTube or other websites, for example).