# I need to replicate this.



## Aukai (Feb 17, 2022)

This is a fishing hydraulic reel holder stand. I will be replicating it in 316 SS, the stub/register I can copy, and drill out for weight savings, but how thick does the flange need to be? In the aluminum it's 5/8" thick, maybe 3/16" would be thick enough? It is a bolt through hole, not threaded, I will weld a pipe to the flange.


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## Bi11Hudson (Feb 17, 2022)

Just an opinion, it really isn't my baliwick. . . I wouldn't go less than 5/16, preferably 3/8. It centers not so much of the absolute strength of stainless vs aluminium but more toward the bending strength of the fasteners and their 'pull through' or tensile strength. Look at the leverage of a fishing pole mounted thereon, 10 lbs on the tip translates to an enormous force at the attachment point. Think long and hard where the stresses come from.

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## Aukai (Feb 17, 2022)

Thank you I have a 4.5" round 316 SS bar to machine down, so I can turn it to what ever. The plate that it bolts to is aluminum that's 1" thick.


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## Eddyde (Feb 17, 2022)

In the absence of any mechanical engineer's input, I would go ½" just to be sure. Also, keep in mind that aluminum and stainless steel are at high risk for galvanic corrosion, especially in a marine environment. Passivated stainless steel bolts and some sort of nonabsorbent, insulating material between the mating surfaces might work, but I'm no expert in that field.


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## Cadillac (Feb 17, 2022)

I think 1/4 is sufficient 3/8 at the most. The pipe you weld to it would fold over before you bent the mounting plate. What’s the wall thickness on tube?


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## tq60 (Feb 17, 2022)

If you are making this from round stock and it is thick, make it not a plate but more of a bushing on plate and NO weld.

I center let it be maybe 2 inches tall and wall thickness 1/4 inch with maybe radius to hole to form sholder.

Bake the vertical shape tapered or artsy, your call.

Have a radius at the bottom where the mounting surface is, let that be large diameter.

Maybe 3/16 thick or so.

Thick enough to allow full countersinking of mounting screws.

To anchor the pipe part you can simply make the bottom of pipe solid, tap for a large bolt or screw.

On bottom of above mount drill and countersink hole then bolt it together.

Loctite and or other sealant coating over all interfacing areas to insure solid and durable.

Remove screw on bottom to clean after assembly and apply anti-sieze then install with full torque.

No welding needed a d will look much better.

Sent from my SM-G781V using Tapatalk


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## Cadillac STS (Feb 17, 2022)

It will help to use some kind of passivation after working the stainless steel.  Stainless is stainless because chromium is at the top layer and prevents the iron from oxidizing.  When you cut it the chromium is there with iron on top also so it can corrode more easily.  The passivation solution reacts with the iron making chromium again on top and protective as much as it can.

CitriSurf 77 Stainless Steel Passivation Cleaner – Commercial Grade (22 ounce)​


			Amazon.com


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## vecair (Feb 17, 2022)

Aukai said:


> This is a fishing hydraulic reel holder stand. I will be replicating it in 316 SS, the stub/register I can copy, and drill out for weight savings, but how thick does the flange need to be? In the aluminum it's 5/8" thick, maybe 3/16" would be thick enough? It is a bolt through hole, not threaded, I will weld a pipe to the flange.




Semper Fi Sergeant Paul H. Foster, USMCR - MOH.  We will not forget.


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## Aukai (Feb 17, 2022)

The reel side is hard anodized, but I can put a buffer. 
Wall thickness is .125
Thanks tq60 another approach to think about.
 I have a bucket of citric acid powder that I use  
Thank you vecair
Thank you all for helping....


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## BGHansen (Feb 17, 2022)

Well, according to Google, 6061 aluminum actually has a little higher yield strength than 316 stainless.  Yeah, doesn't seem right to me either. . .   The ultimate tensile strength is more than double for 316.  Yield strength is the point where the stress has permanently (plastically) deformed by 0.2% of the original length/feature.  UTS is max load before it flat-out breaks.

Your part will deal with a bending moment; important feature is called the moment of inertia.  For something like a 2 x 4, the formula is "(base x height^3) / 12".  For a 2 x 4 laying flat, math is 2.666 vs. 10.666 for a 2 x 4 on edge (4 times stiffer on edge than on a flat).  If you reduce the height by a factor of two (and keep the base the same), the part will have a moment of inertia 12.5% of the original.  If using the same material and loading between the two, your yield strength would also be reduced down by a factor of 8.

Based on the Google charts for yield strength, you shouldn't reduce the flange thickness if you are worried about the part starting to give.  However, your original part may have a large safety factor giving you some room to reduce it in 316 (or aluminum).

If worried about ultimate failure, you should be able to get away with about 1/2" 316 which would give you roughly the same safety factor.

If the aluminum is 0.625" thick, cubing it gives 0.244 in^3.  Since the UTS of the 316 is roughly double 6061, divide the 0.244 by 2 or about 0.125 in^3.  Cube root of 0.125 is 0.5".

All that being said, I had the classes in strength of materials in 1979.  Maybe wait for someone with a better memory than mine to chime in!

Bruce


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## Aukai (Feb 17, 2022)

That's very informative Bruce, thank you. The basic reason I'm changing this out is from my experience fishing over the years. The cross on the end of the holder that lets the pole/hauler fit in the holder, and engage the cross pin that lets the pole/hauler face out, or back wears quickly with heavy use. I have worn out the aluminum butts, and have also snapped the cross pins, so this will keep my son from having to deal with that. I'm trying to make things bullet proof for him, I have 30+ years on the ocean, he was not forced to be with me, and had other things to do, so he's just learning now.


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## Aukai (Feb 17, 2022)

Well I worked through nap time, and got it done. CNMG 431 worked well, parting was an adventure, but got it figured out. I just need to mark the holes to drill.


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## Aukai (Feb 19, 2022)

Got some more work done, transfer screws work great.


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## Aukai (Feb 20, 2022)

I need LOT'S more practice, and I hope it's good enough to hold. I have it soaking in it's bath right now.


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