Ss. Tank bands and ss. Backplate

[Seraphimx]

The half round should be made out of tubing since it would purge of water easier.

It's finally not that cheap.

Material + Laser + Bending = 55$ for SS.316 45$ for SS.304 55$ for Aluminium (He can surely lower his price if I make more quantity)
You have to add 2hours @ 20$ for buffing sharp slots and polishing.

90$ a plate

(I never understood how aluminium backplates can be cheaper than SS since Aluminium is expensive)
Maybe because I can only get T5 or T6 grade for structural and architectural works and that is too strong and overrated for BP/W?


Furthermore, the H-Plate's design bends are too near each others. They can't do it because they don't have the equipment for it.
Their bending bench is not strong enough to make those, so I'll have to go ask the shop that specializes in bending (he doesn't like me much).

I should receive the normal plate sample (not free though) in a week (with how much late time?).

 

[mike1010]

sounds interesting. i'd like to see pictures when you slot the holes would you be able to make the slots further apart to try out the cinch setup? also is it possible to use 316 stainless or is that too expensive or difficult to work with?
edit
read your post better, seems like using 304 woulden't be worth it for 10$ difference.

 

[Seraphimx]

I work in steel construction and marine grade 316L (don't forget the L) is used in case a ladder is 100% of the time immersed in water (any type of water).
Or we also use aluminium in such cases too.

If you think about it.

A grade 316L in water 24/7 won't rust.
You make 4x 30min dive per days (someone really fanatic) you are basically 8% of the time in water.
If you only dive on the weekeds, you are 1.2% of the time in water.
Is it worth it?

I'll receive the plate unbent and already with the holes cut (it's laser cut). But the slots & holes will be have really sharp edges that will need to be buffed/grinded.

316L Grade stainless IMHO is a waste of $.
If you are a dive professional and make 4 dives per day, maybe.
If you are only diving on weekends, useless.

316L is more expensive than 316.
316 is more expensive than 304.

I'd do the plate in the cheapest material at the moment and once I get the design 100% sure I'll do it in 316.

The plate with the cinch I'll have to redraw a sketch and add the spacing for the tubing. I'll resend it to cutting but I'll ask it to be in standard steel and we'll go from there.

 

[mike1010]

Sounds good I only know about steel form the little online research I've done. the only design thing i think is really important is that the tubing be solid. with the weight of the tank or 2 tanks on that area i think solid would work better. I've got some 5/8" round bar coming in the mail now I'm going to try on my Oms plate, to see if the idea is worth using if it works it can be put on the plate I'd like to buy from you. I can see if the spacing of 5/8 is adequate as well.

 

[Seraphimx]

I understand what you mean but a round surface is always stronger, furthermore the tubing is so small that it would need A LOT of force to damage it. I mean you would literally need to take a sledgehammer and hit on it to bend the half circle. The smaller the diameter of the tubing the stronger it'll be.

1) It's easier to cut a half tube than a half solid.
2) I'm thinking of water infiltration. If you weld the solid bar you need to make sure you have sealed welds.
3) Time, seal welds takes time and you have to be sure it's done correctly, if it's not done correctly infiltration will start rusting that area.



That's why I'm saying a hollow tubing would work better, you finish using the BP, you rinse it with fresh water and you're done.

Also if you weld, it seems (as per an engineer's opinion) that we would be better off using 304L (didnt know it existed) or 316L. He says the heat of the welding on the welded area degraded the SS and it can rust easier on the welds. While with "L" grade, the Welds reform the protection and stay as before.

Does anyone have an halcyon cinch system that can be used to measure the height of the round part and so on.

1 week to go

 

[mike1010]

I can look at my buddy's setup and take some measurements if that would help. but if you can find the gap distances on a halcyon plat that should also give you an idea of how far the slots need to be.

 

[mike1010]

Update
So i received the round bar and am testing it out.

 

[Seraphimx]

Just received an halcyon plate, I'll check it out but i received a SMALL PLATE DAMMIT!

 

[mike1010]

did not know they came in sizes...

 

[Seraphimx]

Yes, there's normal or small for a small people. Well I'm not so tall (5ft-6in) so I don't know if it'll be a problem or not.
Still haven't checked for the spacing, totally forgot about it.
I'll need a reminder

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