Dear Sir, I sincerely appreciate the effort you put into this Strut Structures video. I am a semi-retired mechanical designer and I have used struts fitted with rod ends on several occasions. Accommodating differential thermal growth with six rod end struts is frequently a life-saving design solution. The content and graphics in your video are outstanding. I’m sure you are aware of the following details, but for the benefit of the young designers among your followers, may I share a few additional thoughts? 1) One of the helpful features of struts with rod ends is infinite length adjustment. If right and left-hand threads are used on the rod ends, the strut becomes a turnbuckle. There aren’t many structural elements that accommodate tolerance like a turnbuckle. This can be a lifesaver during assembly. 2) If your application can tolerate a weight and cost penalty, the single-point failure issue can be mitigated to a degree with redundancy in the end fittings. A sleeve tube over the axel bolt and dual clevis ears on both sides can help. A sleeve tube within the outer tube can offer a degree of redundancy to the strut. However, from a practical standpoint, just making sure you have adequate stress margins and a conservative life limit is usually the most cost-effective approach. 3) In my rod end explorations, I have picked up a few helpful tips: • Plain bearing rod ends are very affordable. A male rod end with ¼ - 28 fine thread stem costs $5.43 from McMaster Carr www.mcmaster.com/products/rod-ends/ball-joint-rod-ends-10/ as of today, 06/20/2023 • The plane bearing rod ends with the fiber-filled Teflon liners are durable and work well in many applications. • Rod ends with double row ball bearings are available at a higher price www.mcmaster.com/products/bearings/rod-ends-and-linkages/high-speed-ball-bearing-rod-ends-7/ Ball bearing rod ends are used in aircraft control linkages and animatronic mechanisms. They offer smooth operation by eliminating stiction or breakaway friction and jerky motion. www.pic-designcatalog.com/heim-rod-ends/heim-ball-bearing-rod-ends/ rathibearings.com/products.php • Large rod ends (2.0" bore diameter) made from high-strength steel can handle more 300,000 pounds of static radial loads. radialbearing.com/wp-content/uploads/2018/05/Rad-Bear-Catalog-2012Imp-R4.2-3.pdf • Conical spacers or washers mounted on the sides of the spherical bearing allow full angular deflection. • At least one off-road rod end company offers “misalignment bushings” that enable up to 60 degrees (30 degree half-angle) of angular deflection: www.fkrodends.com/products/special-products/commercial-series-3/ Be aware that the additional deflection comes at the price of a reduction in strength due to a smaller diameter through bolt. Increase the size of the rod end as needed. • At least one company www.ridetech.com/products/r-joint-en/ offers a spring-loaded self-adjusting wear compensating feature in their suspension rod ends. • Rubber boots and face seals are available to protect exposed rod ends from dirt. Caution: If the booted rod ends will be exposed to water and mud, inspect the seals for cracks frequently. The boots can retain water, leading to corrosion and shortened rod end life. • At least one company www.rbcbearings.com/Engineering/Ball-Bearing-Rod-Ends can custom make high temperature (1,200°F) rod ends I look forward to your forthcoming video on end fittings for the rod ends. Thank you. Van
As a structures/stress engineer, this video was super informative! It was almost like learning from a mentor on the job at work :) Looking forward to learning more from you!
This is quality content good sir! I recreated the script with little effort even as a python newb! I am however stuck on being able to plot your final results with changing loads. Any hints would be appreciated! Keep it up, I'll be checking out all your other videos.
Thanks! Glad someone was able to follow along. Here's what I did to plot the loads: load_array = np.arange(0, totalloads, 1) for i in range(0,6): tmplabel = 'Strut '+ str(i+1) plt.plot(load_array, sol[i, :], label=tmplabel)
Dear Sir,
I sincerely appreciate the effort you put into this Strut Structures video. I am a semi-retired mechanical designer and I have used struts fitted with rod ends on several occasions. Accommodating differential thermal growth with six rod end struts is frequently a life-saving design solution. The content and graphics in your video are outstanding.
I’m sure you are aware of the following details, but for the benefit of the young designers among your followers, may I share a few additional thoughts?
1) One of the helpful features of struts with rod ends is infinite length adjustment. If right and left-hand threads are used on the rod ends, the strut becomes a turnbuckle. There aren’t many structural elements that accommodate tolerance like a turnbuckle. This can be a lifesaver during assembly.
2) If your application can tolerate a weight and cost penalty, the single-point failure issue can be mitigated to a degree with redundancy in the end fittings. A sleeve tube over the axel bolt and dual clevis ears on both sides can help. A sleeve tube within the outer tube can offer a degree of redundancy to the strut. However, from a practical standpoint, just making sure you have adequate stress margins and a conservative life limit is usually the most cost-effective approach.
3) In my rod end explorations, I have picked up a few helpful tips:
• Plain bearing rod ends are very affordable. A male rod end with ¼ - 28 fine thread stem costs $5.43 from McMaster Carr www.mcmaster.com/products/rod-ends/ball-joint-rod-ends-10/ as of today, 06/20/2023
• The plane bearing rod ends with the fiber-filled Teflon liners are durable and work well in many applications.
• Rod ends with double row ball bearings are available at a higher price www.mcmaster.com/products/bearings/rod-ends-and-linkages/high-speed-ball-bearing-rod-ends-7/ Ball bearing rod ends are used in aircraft control linkages and animatronic mechanisms. They offer smooth operation by eliminating stiction or breakaway friction and jerky motion. www.pic-designcatalog.com/heim-rod-ends/heim-ball-bearing-rod-ends/ rathibearings.com/products.php
• Large rod ends (2.0" bore diameter) made from high-strength steel can handle more 300,000 pounds of static radial loads. radialbearing.com/wp-content/uploads/2018/05/Rad-Bear-Catalog-2012Imp-R4.2-3.pdf
• Conical spacers or washers mounted on the sides of the spherical bearing allow full angular deflection.
• At least one off-road rod end company offers “misalignment bushings” that enable up to 60 degrees (30 degree half-angle) of angular deflection:
www.fkrodends.com/products/special-products/commercial-series-3/ Be aware that the additional deflection comes at the price of a reduction in strength due to a smaller diameter through bolt. Increase the size of the rod end as needed.
• At least one company www.ridetech.com/products/r-joint-en/ offers a spring-loaded self-adjusting wear compensating feature in their suspension rod ends.
• Rubber boots and face seals are available to protect exposed rod ends from dirt. Caution: If the booted rod ends will be exposed to water and mud, inspect the seals for cracks frequently. The boots can retain water, leading to corrosion and shortened rod end life.
• At least one company www.rbcbearings.com/Engineering/Ball-Bearing-Rod-Ends can custom make high temperature (1,200°F) rod ends
I look forward to your forthcoming video on end fittings for the rod ends.
Thank you.
Van
Thank you, this is some great information!
Bro as an Mechanical UG guy I feel that ur miscellaneous bits are more motivating to me. Pls continue uploading more of these content. Thanks man...
Bookmarking as this will undoubtedly come in handy at some point, awesome resource, man.
I agree with you on your position regarding squares
As a structures/stress engineer, this video was super informative! It was almost like learning from a mentor on the job at work :) Looking forward to learning more from you!
Looking forward to your next video on this topic!
This is quality content good sir! I recreated the script with little effort even as a python newb! I am however stuck on being able to plot your final results with changing loads. Any hints would be appreciated! Keep it up, I'll be checking out all your other videos.
Thanks! Glad someone was able to follow along. Here's what I did to plot the loads:
load_array = np.arange(0, totalloads, 1)
for i in range(0,6):
tmplabel = 'Strut '+ str(i+1)
plt.plot(load_array, sol[i, :], label=tmplabel)
Great video! Is there any chance you might be interested in making a video on building and programming a Stewart Platform?
Just awesome details bro advertise yourself more, your channel is good!
Thanks for your great content. Keep it coming 💯💯💯👍
noice..keep it up man. i enjoy watching this video.
gonna check your other videos
Thanks!
Very informative awesome ❤