help with clamp selection for solar car struts project

[isfar rahman]

Hello. My name is Isfar Rahman and I am a designer of the Structures subteam in my engineering student design team, UBC Solar. My design team has previously purchased carbon fiber tubing from your company.

I am currently working on the Struts of our solar car, Brightside. Essentially, we are looking to replace the current steel struts that we have, with carbon fiber tubes that we have in stock and telescoping clamps. The struts would help support the topshell of our car and help keep open the topshell in different angles. I am aware that you have tubes specifically made for telescoping purposes with built in tolerances, but my team would really like to use up the current carbon fiber tubes that we have.

Here's a picture of the inside of the aeroshell of our car, for reference. I highlighted the part (in blue) I am working on to give you a better idea of what I'm talking about.

 

Currently we have a few different tube diameters but I was wondering if it would fit any of the clamps that you have? I am specifically looking for one of the Telescoping clamps - INFINITube sizes to fit my tubes. If you think any other type of clamp like the Flip and Twist locking clamps for INIFINITubeV would be compatible, I would appreciate the recommendation. 

These are the tube descriptions that came along with the box. However I just want to add that the tubes I am talking about (and have pictures of below) are not the unidirectional tubes, but the pultruded and pole winded tubes.
46319 - Tube - Unidirectional - 0.314 x 0.398 x 60 inch

45167 - Tube - Unidirectional - 0.553 x 0.625 x 72 inch

45582 - Tube - Unidirectional - 0.46 x 0.52 x 60 inch

FSAE2020 (not sure what this is but it came along with the product description)
 

I can send you pictures and the dimensions of the tubes that I measured with our own equipment.

outer diameter: 21.86 mm or 0.86 in
inner diameter: 18.37 mm or 0.72 in

 

outer diameter: 13.21 mm or 0.52 in

inner diameter: 10.9 mm or 0.43 in

outer diameter: 17.22 mm or 0.68 in
inner diameter: 14.56 mm or 0.57 in

 

outer diameter: 23.35 mm or 0.92 in

inner diameter 18.42 mm or 0.73 in

 

I was looking through your website and I came across a PDF file that led me to believe if I would have any luck finding a size for a clamp that would fit one of our tubes, the tube with the closest dimension to one of your clamps would be the very last one (dimensions in bold). However, I still wanted to cross check with you if you think that's a good idea, or if it would fit.

[lo_0l]

On 11/23/2024 at 1:43 PM, isfar rahman said:

Hello. My name is Isfar Rahman and I am a designer of the Structures subteam in my engineering student design team, UBC Solar. My design team has previously purchased carbon fiber tubing from your company.

I am currently working on the Struts of our solar car, Brightside. Essentially, we are looking to replace the current steel struts that we have, with carbon fiber tubes that we have in stock and telescoping clamps. The struts would help support the topshell of our car and help keep open the topshell in different angles. I am aware that you have tubes specifically made for telescoping purposes with built in tolerances, but my team would really like to use up the current carbon fiber tubes that we have.

Here's a picture of the inside of the aeroshell of our car, for reference. I highlighted the part (in blue) I am working on to give you a better idea of what I'm talking about.

 

Currently we have a few different tube diameters but I was wondering if it would fit any of the clamps that you have? I am specifically looking for one of the Telescoping clamps - INFINITube sizes to fit my tubes. If you think any other type of clamp like the Flip and Twist locking clamps for INIFINITubeV would be compatible, I would appreciate the recommendation. 

These are the tube descriptions that came along with the box. However I just want to add that the tubes I am talking about (and have pictures of below) are not the unidirectional tubes, but the pultruded and pole winded tubes.
46319 - Tube - Unidirectional - 0.314 x 0.398 x 60 inch

45167 - Tube - Unidirectional - 0.553 x 0.625 x 72 inch

45582 - Tube - Unidirectional - 0.46 x 0.52 x 60 inch

FSAE2020 (not sure what this is but it came along with the product description)
 

I can send you pictures and the dimensions of the tubes that I measured with our own equipment.

outer diameter: 21.86 mm or 0.86 in
inner diameter: 18.37 mm or 0.72 in

 

outer diameter: 13.21 mm or 0.52 in

inner diameter: 10.9 mm or 0.43 in

outer diameter: 17.22 mm or 0.68 in
inner diameter: 14.56 mm or 0.57 in

 

outer diameter: 23.35 mm or 0.92 in

inner diameter 18.42 mm or 0.73 in

 

I was looking through your website and I came across a PDF file that led me to believe if I would have any luck finding a size for a clamp that would fit one of our tubes, the tube with the closest dimension to one of your clamps would be the very last one (dimensions in bold). However, I still wanted to cross check with you if you think that's a good idea, or if it would fit.

Hi @isfar rahman,

It doesn't look like any of your pictures made it through! Can you try fixing them?

You mentioned struts. Are you referring to gas struts?

[isfar rahman]

oh! yes here you are. for some reason the pictures show up just fine on my end. i'll reattach them now.

picture of the inside of the aeroshell of our car:

these are are the tubes that we currently own:

outer diameter: 21.86 mm or 0.86 in
inner diameter: 18.37 mm or 0.72 in
 

outer diameter: 13.21 mm or 0.52 in

inner diameter: 10.9 mm or 0.43 in

 

outer diameter: 17.22 mm or 0.68 in
inner diameter: 14.56 mm or 0.57 in

 

outer diameter: 23.35 mm or 0.92 in

inner diameter 18.42 mm or 0.73 in

 

to answer your question, the struts here are not gas struts. it's simply a support structure that holds up the topshell of our car. i hope this helps! 

 

[lo_0l]

On 12/3/2024 at 5:19 PM, isfar rahman said:

oh! yes here you are. for some reason the pictures show up just fine on my end. i'll reattach them now.

picture of the inside of the aeroshell of our car:

these are are the tubes that we currently own:

outer diameter: 21.86 mm or 0.86 in
inner diameter: 18.37 mm or 0.72 in
 

outer diameter: 13.21 mm or 0.52 in

inner diameter: 10.9 mm or 0.43 in

 

outer diameter: 17.22 mm or 0.68 in
inner diameter: 14.56 mm or 0.57 in

 

outer diameter: 23.35 mm or 0.92 in

inner diameter 18.42 mm or 0.73 in

 

to answer your question, the struts here are not gas struts. it's simply a support structure that holds up the topshell of our car. i hope this helps! 

 

You could. Sometimes the simplest solution is the best solution though...

It looks like you have long enough pieces to make a single piece shaft. I would just cut them to the size you need if you can. That would keep the weight down. Maybe have two different ones if you need variable height. It'd be worth measuring the clamps and figuring out the weight of an adjustable tube, vs one tube, vs two tubes. Depending on the rules, it might even be better to just keep this on your support vehicle to nix the weight completely.

If you need this adjustable, I'm more than happy to look into this for you 🙂

[isfar rahman]

Hello! Sorry about the very late response, it's currentlt finals season for us. Thank you so much for your reply. I would really appriciate if you could look into this for me, thank you so much.

I'm still a bit confused though. Are you saying the tubes that I have, with the current dimensions, can be used for telescoping purposes? I thought we only could use the infitubes that you guys offer, for that. I was wondering if you guys have clamps that would fit the current tube dimensions we do have. Or if you made custom clamps that we would order to fit the current tubes that we do have. 

Thank you!

[isfar rahman]

Hello there!

I just wanted to check in and just give you an update on the requirements on the project: that adjustability is a requirement for the project. I apologize if it wasn't clear before. Do you have any carbon fiber tubes that aren’t specifically designed for telescoping but have appropriate tolerances and sizes suitable for clamps, so we can create our own telescoping system? Or if we can customize tubes such that the tubes we order can match telescoping tolerances and match (fit into) the dimensions of the tubes that we currently have?

Thank you!

[lo_0l]

On 12/28/2024 at 10:33 AM, isfar rahman said:

Hello there!

I just wanted to check in and just give you an update on the requirements on the project: that adjustability is a requirement for the project. I apologize if it wasn't clear before. Do you have any carbon fiber tubes that aren’t specifically designed for telescoping but have appropriate tolerances and sizes suitable for clamps, so we can create our own telescoping system? Or if we can customize tubes such that the tubes we order can match telescoping tolerances and match (fit into) the dimensions of the tubes that we currently have?

Thank you!

Hi again @isfar rahman, apologies for the delay. I've sent this over to the Rock West Composites Customer Service Team!