80/20 Lighting Mount Help!

AngryOwl · Oct 30, 2018

Sweet! Btw you replied in between the quote ;Hilarious

I think I am on to something. I used the deflection calculator for series 25 25mm x 50mm and with an end load of 60 pounds deflection was 4 inches. This doesn't account for an angled mitered support. It's cheap enough for justify doing two arms as opposed to 1... which might turn out better in the end.

That is some serious lead time... would you recommend any addons they offer like the access hole? Or end tap?

Do fastening brackets come with the screws? Also do the screws actually penetrate the 80/20?

Lol noob questions but if I'm designing something holding 60 pounds over my tank... I better be confident it's going to be okay because we all know what will happen it it gives.

Talo’s Reef · Oct 30, 2018

AngryOwl said:
Sweet! Btw you replied in between the quote ;Hilarious

I think I am on to something. I used the deflection calculator for series 25 25mm x 50mm and with an end load of 60 pounds deflection was 4 inches. This doesn't account for an angled mitered support. It's cheap enough for justify doing two arms as opposed to 1... which might turn out better in the end.

That is some serious lead time... would you recommend any addons they offer like the access hole? Or end tap?

Do fastening brackets come with the screws? Also do the screws actually penetrate the 80/20?

Lol noob questions but if I'm designing something holding 60 pounds over my tank... I better be confident it's going to be okay because we all know what will happen it it gives.

Yes, yes I did.

I know next to nothing about deflection and stuff like that so I would refer to someone else for those questions however, you 60lb load wouldn’t just be on the end, it would be spread out over the length of the bar. At the end of the day the couple bucks for the machining was inconsequential to the final price and I’m not a diy-er. FYI, after all the fasteners I would not consider it cheap, adds up fast, although I ended up with four arms (2 separate lights with 2 arms each).

It will say in the description if they come with screws or not and usually have pictures on how they attach to the bars so you can get a good idea of how everything will fit together and the different options. No they do not penetrate the aluminum. The screws hold tension with the t nut. I ran into an issue where I had some screws that were too long and were not flush.

As for you last question, that is why I Would consult with them about the strength and deflection because that would be a very bad thing I imagine.

AngryOwl · Oct 30, 2018

Talo’s Reef said:
Yes, yes I did.

I know next to nothing about deflection and stuff like that so I would refer to someone else for those questions however, you 60lb load wouldn’t just be on the end, it would be spread out over the length of the bar. At the end of the day the couple bucks for the machining was inconsequential to the final price and I’m not a diy-er. FYI, after all the fasteners I would not consider it cheap, adds up fast, although I ended up with four arms (2 separate lights with 2 arms each).

It will say in the description if they come with screws or not and usually have pictures on how they attach to the bars so you can get a good idea of how everything will fit together and the different options. No they do not penetrate the aluminum. The screws hold tension with the t nut. I ran into an issue where I had some screws that were too long and were not flush.

As for you last question, that is why I Would consult with them about the strength and deflection because that would be a very bad thing I imagine.

Haha yes I will verify most certainly! You're absolutely correct the weight would not be over the end point but I am only pointing it out as a worse case reference if that makes sense. Over engineering in another sense.

With 2 arms, a 45 degree supportand angled mounting bracket this 'should' be plenty.

Thanks for the tips! I will update this thread with my decisions and parts so some poor soul of the future can figure it out!

Talo’s Reef · Oct 30, 2018

AngryOwl said:
Haha yes I will verify most certainly! You're absolutely correct the weight would not be over the end point but I am only pointing it out as a worse case reference if that makes sense. Over engineering in another sense.

With 2 arms, a 45 degree supportand angled mounting bracket this 'should' be plenty.

Thanks for the tips! I will update this thread with my decisions and parts so some poor soul of the future can figure it out!

Can’t wait to see it.

Good luck!!

AngryOwl · Oct 30, 2018

Two options I'm playing with for the 80/20 and I'm still waiting on design assistance. I've decided it will probably be best and easier to do 2 arms for distributed support. I will then use corner bracing on both sides of each arm and put in an angled cross brace as well. I've decided to use black and the 25 series 80/20.
So now it is coming down to 2 options for me on the profile.
1) 25 x 50mm - with an end load this gives me deflection of 4.1 inches (for those unfamiliar, deflection is basically how much the material will bend under the span and weight) This calculation is for 1 arm and does not take into account the angled cross bracing. Cost per inch .55.
2) 25 x 75mm - with an end load this gives me deflection of 1.5 inches. Cost per inch .78.

Cost difference here is minimal and peace of mind is priceless. Either option will work just fine I think but option 2 has additional peace of mind. With 2 arms potentially only holding 30 pounds each, I should see minimal deflection, most likely I won't even notice it. Total cost for this is looking to be in the $400-500 range which isn't terrible.

Let me know your thoughts!

pelphrey · Oct 30, 2018

Pick series, sort fasteners by series, check bottom tab of fasteners for hardware! I buy from 8020.net

I used 10 series. I’ve talked about it a few times in my videos and it’s in my build thread... somewhere! Haha

AngryOwl · Oct 30, 2018

pelphrey said:
Pick series, sort fasteners by series, check bottom tab of fasteners for hardware! I buy from 8020.net

I used 10 series. I’ve talked about it a few times in my videos and it’s in my build thread... somewhere! Haha

I'm getting the hang of searching for things now. I'm looking at series 15 after some design assistance feedback.

But I am caught in-between using 2 arms or just 1. I think the look of two arms will make more sense over the tank but it of course doubles the cost. What do you think?

AcanthurusRex · Oct 31, 2018

The 10 series deflects considerably supporting an aquatic life hybrid with 18 in arms. I think you will need a bigger series for this application.

AngryOwl · Oct 31, 2018

AcanthurusRex said:
The 10 series deflects considerably supporting an aquatic life hybrid with 18 in arms. I think you will need a bigger series for this application.

Yea I'm going to go with series 15, 1.5" x 4.5"... this gives me .22" of deflection if the arm is end loaded (which it won't be).

Talo’s Reef · Dec 1, 2018

A

AngryOwl said:
Yea I'm going to go with series 15, 1.5" x 4.5"... this gives me .22" of deflection if the arm is end loaded (which it won't be).

any update?

AngryOwl · Dec 1, 2018

Talo’s Reef said:
A

any update?

I went with the Series 15 1.5" x 4.5" black extrusion. I ordered on November 6th and they shipped it out on Friday. According to the tracking it should arrive on Wednesday. Great timing since my tank is also being delivered Wednesday.

On cyber Monday they had a 15% off sale and after some back and forth with customer support I got them to honor the sales price for me. Total came to $530 and I will be getting a little over $70 back.

I'll update once it's here and installed. Chances are greater it will be on my build thread first though

Talo’s Reef · Dec 1, 2018

AngryOwl said:
I went with the Series 15 1.5" x 4.5" black extrusion. I ordered on November 6th and they shipped it out on Friday. According to the tracking it should arrive on Wednesday. Great timing since my tank is also being delivered Wednesday.

On cyber Monday they had a 15% off sale and after some back and forth with customer support I got them to honor the sales price for me. Total came to $530 and I will be getting a little over $70 back.

I'll update once it's here and installed. Chances are greater it will be on my build thread first though

I’ll keep my eyes peeled