Replacing frame struts on my pack

Posted by: kd6hul

Replacing frame struts on my pack - 09/11/15 05:56 AM

One of the carbon fiber struts on my North Face Patrol has broken and North Face is being stinky about fixing it. I'd like to try my hand at forming two new struts out of t6061 aluminium bar stock. Does anyone have any suggestions, including alternative materials? I have a well-equipped shop and a good assortment of tools with which to work. I also have a master welder who can help if needed.

Posted by: BZH

Re: Replacing frame struts on my pack - 09/11/15 11:09 AM

What are the dimensions of the carbon fiber you are replacing? or... are they fiberglass? I think I created a spreadsheet one time for someone looking to match the stiffness between different materials for backpack struts.

6061 tube would be good. I would think bar stock would either be too bendy or too heavy. You could get some carbon fiber tubes:

If you want to stay a bit cheaper, many people like to use arrow shafts (used or new/clearance if you can find them).
Posted by: CamperMom

Re: Replacing frame struts on my pack - 09/12/15 12:01 PM


Have you considered trying to repair the broken struts. I ask because hubby successfully repaired my carbon fiver hiking pole. I have serious difficulty finding the broken spot, even telling which pole was broken. It totally snapped and splintered when I fell on it as it was held above a downed tree and large rock. My opposite leg was skinned up pretty well, but it was the ruined pole that had me close to tears. We were able to find a broken carbon fiber arrow shaft that was a close fit to the pole's inner diameter, inserted a section then used a form of 5 minute epoxy as a filler/glue, smoothing as the repair was accomplished. Send me a PM if you want to get into more detail via phone.

Posted by: finallyME

Re: Replacing frame struts on my pack - 09/15/15 04:25 PM

I am not familiar with those struts exactly, but I would recommend a 7000 aluminum over a 6000. It will be more rigid.
Posted by: Jim M

Re: Replacing frame struts on my pack - 09/25/15 12:45 PM

I am considering wood dowel. Just an experiment, but they would be lighter. If they broke they could be repaired with duct tape. Contour isn't too important to me; my back seems not to mind much of anything. I went for a walk in the woods yesterday with no stays and 23 lbs. and the pack felt fine to me.
Posted by: BZH

Re: wood - 09/25/15 01:58 PM

I would (wood?) use bamboo poles before wood dowels. Much more flexible and light.
Posted by: Jim M

Re: wood - 11/24/15 12:24 PM

Bamboo! I never thought of that. I will definitely try that.
Bamboo is amazingly light for its strength, I know that much.
Posted by: OregonMouse

Re: wood - 11/24/15 04:11 PM

If you don't want something that bends, arrow shafts, as mentioned above, would be the lightest.

Or flat aluminum, which can be bent, and is used for a lot of pack stays.
Posted by: Jim M

Re: wood - 12/21/15 09:31 PM

Well, I tried bamboo but the aluminum stays on my REI flash 50 are in such small, narrow, pockets that any bamboo (wands) I had were too large (and just a little lumpy) so they didn't fit.
Posted by: whitebaby

Re: Replacing frame struts on my pack - 12/25/15 10:22 PM

You can have a try the OUTAD Aluminum Alloy Folding Alpenstock,I own one of this Alpenstock,it is very useful to me,especially in the snow day.
Posted by: CamperMom

Re: wood - 12/26/15 08:15 AM

So, if you are ready to consider a piece of arrow shaft, contact me. I would be quite willing see if anything I can find is a reasonable match in diameter.