Gurus, will this beam for sliding door hardware work?

[mike sato]

I have Johnson 100PD pocket door hardware that's 6 feet long. Max load is 125 lbs.

johnson-hardware-pocket-door-hardware-100721dr-64_1000.jpg


Instead of a door, I need to support a load that's 75 lbs, supported by rope on two sides. The spacing of the ropes is 26 inches apart.

I'm currently using a 2x4 (1.5 x 3.5 inches) lumber (typical treated 2x4) as the supporting beam with the 3.5" side vertical, and that works fine to support the sliding door hardware to hold 75 lbs. But this setup is heavier than I want it to be.

After Googling for hours, I can't find out if I can use a 2x3 (1.5 x 2.5 inches) for the beam. Reason I want to use a 2x3 treated lumber for the beam is that the project has to be portable and assembled every time I use it, and I want to minimize the weight as much as possible. Actual length of the beam will be 6'8". (6' for the sliding door hardware and 4" on both sides for support.)

Since the info does not seem to be available on the web, I'm asking you gurus:
... From your experience, will a 2x3 work as the supporting beam? I think it will but I'm hoping to get 2nd opinions before I buy a 2x3x8' lumber.

[Paul F Franklin]

Will the 2x3 be supported on both ends with the load sliding in between, or will it be supported only at one end with the load cantilevered? If the latter, what is the length of the cantilevered part of the beam?

[Tom M King]

Johnson makes several heavier styles of tracks, in different weight ranges. I always liked the T-shaped tracks the best, with rollers that go on either side of the I-beam. Even the smaller T-tracks are a lot sturdier than that U-shaped one. Some of those heavier tracks would support that load without any beam. I know of some I installed in closets, with solid wood by-pass doors, in 1974 that still work like new. I use them for pocket doors too.

You can buy individual parts, as well as complete sets, direct from Johnson.

[mike sato]

Will the 2x3 be supported on both ends with the load sliding in between, or will it be supported only at one end with the load cantilevered? If the latter, what is the length of the cantilevered part of the beam?

The 2x3 will be 6'8" long supported on both ends. The 6' long track will be mounted in between.

[mike sato]

Johnson makes several heavier styles of tracks, in different weight ranges. I always liked the T-shaped tracks the best, with rollers that go on either side of the I-beam. Even the smaller T-tracks are a lot sturdier than that U-shaped one. Some of those heavier tracks would support that load without any beam. I know of some I installed in closets, with solid wood by-pass doors, in 1974 that still work like new. I use them for pocket doors too.

You can buy individual parts, as well as complete sets, direct from Johnson.

Thanks for your reply. I already bought the 100PD hardware and am using it mounted on the 2x4. Just want to know if I can replace the 2x4 with a 2x3 and still be strong enough.

..... Folk's best guess will be fine.

[Paul F Franklin]

A 2x3 will support a 75 lb load in the center of a 6' 8" span supported on both ends with only minor sag. I realize your load will be more distributed, but having it all in the center of the span is worst case.

[Tom M King]

Should be plenty strong enough.

[mike sato]

A 2x3 will support a 75 lb load in the center of a 6' 8" span supported on both ends with only minor sag. I realize your load will be more distributed, but having it all in the center of the span is worst case.

Should be plenty strong enough.

Paul & Tom,

Thanks for your opinions. I'm going to go ahead with using a 2x3. In fact, I'm going to rip the 2x4 I already have to 2x3 and save time and gas for a trip to the lumber store.

[mike sato]

Paul & Tom,

Thanks for your opinions. I'm going to go ahead with using a 2x3. In fact, I'm going to rip the 2x4 I already have to 2x3 and save time and gas for a trip to the lumber store.

Ripped the 2x4 to 2x3. Will post results after I reassemble and test it.

[mike sato]

Ripped the 2x4 to 2x3. Will post results after I reassemble and test it.

I estimate that there is about 1/16" sag in the 2x3 with the load centered on the beam. This is just by sighting down the beam so is a very unscientific estimate. A negligible of amount of sag with zero affect on usage and zero chance of breakage.

Thanks.

[Paul F Franklin]

Good to hear, thanks for circling back! So what is this mysterious contraption?

[mike sato]

Good to hear, thanks for circling back! So what is this mysterious contraption?

The gizmo is a way to remove the heavy 2nd row seats from any minivan. Our new 2019 Honda Odyssey van's 2nd row seats cannot be folded down so they have to be removed manually to open up cargo space. I've already pulled my back 4 times in the past for other things and am determined not to pull my back removing the seats. I got the gizmo working and will post a video on youtube when I have time later. (Correction: Each seat weighs 61 lbs, not 75 lbs)

Meanwhile, here's some links to some other usefulgizmos that I've already posted on youtube that folks here might find interesting:

5x Quieter generator quiet box
https://www.youtube.com/watch?v=_qPRIq-9U-4

Pro miter saw stand
https://www.youtube.com/watch?v=_BBjEDVueIY&t=317s

Easy DIY Scaffold
https://www.youtube.com/watch?v=c0b0kw99mK4&t=232s

How to install Hurricane Plywood by one person
https://www.youtube.com/watch?v=AJ5-o_fdI38

Thanks.