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Several of my Aluminum Stanchion Bases are cracking. Most likely due to the stainless steel stanchion inserted into the aluminum base with a SS Screw holding it. Looking for either a source for replacement parts or an alternative solution. I'm located in Southern California and Minney's doesn't have them. A foundry will make the mold and cast them for $2,200, but I only need 10. $220 each is expensive and would like a cheaper solution.

Thanks for any help.
 

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Farr 11.6 (Farr 38)
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I second the suggestion to have Garhauer fabricate stanchion bases for you. I had them fabricate custom stanchion bases for my boat with a bolt pattern and baseplate size and shape that matched my old bases. I also specified a thicker baseplate, taller tube, and a thicker rod that braces the base. The price was only slightly more expensive than their standard price. They also made custom stainless steel backing plates with mstching the bolt holes for $8.00 ea.

The hard part is that the bottom of your bases jog over the toe rail and appear to have a vertical leg that bolts into toe rail.

I will note that those look like bases that were made by Goiot.

Jeff
 

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Bases partially on the top rail flange and partly on the deck are a problem. I replaced my aluminum bases years ago with stainless steel. It involved using a shim plate between the base and the deck:
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Bases partially on the top rail flange and partly on the deck are a problem. I replaced my aluminum bases years ago with stainless steel. It involved using a shim plate between the base and the deck:
View attachment 141507
While a shim plate helps with the geometry problem, it greatly weakens the assembly and is more likely to leak. In that picture

Also as a heads up to DIYers out thee, it is also really bad engineering to have that fill hole in the deck so close to the stanchion base.

Jeff
 

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While a shim plate helps with the geometry problem, it greatly weakens the assembly and is more likely to leak. In that picture

Also as a heads up to DIYers out thee, it is also really bad engineering to have that fill hole in the deck so close to the stanchion base.

Jeff
The installation has been in place for over 30 years and seems fine. No leaks. I can't assess the strength of the stanchions... but in one incidence when I was tossed over the lifelines while clipped on there was no "distortion" of the lifeline "system" including failure of the stanchion assembly. That was predictably a large dynamic load. I think my DIY installation passed the test.
 

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Discussion Starter · #10 ·
I emailed Garhauer photos last night and received a response and a contact to call this morning. I called and spoke to Mike and he was very helpfull. They can custom fabricate the part and Mike had some great ideas for the design. We discussed a shim as it makes it easier to fabricate. I have purchased Garhauer products before and they make great stuff so I think I will go for it.

FYI-Sticking a Stainless Steel Stanchion in an Aluminum base for 25 years, even with an insulator seperating the two, is a bad idea. The stanchion is stuck. Pipe wrenches only leave marks in the metal. I'm not sure using heat with a torch will work. Will most likely have to cut thru the base to remove the stanchion.

Thank you guys for your responses.

Brad
 

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While a shim plate helps with the geometry problem, it greatly weakens the assembly and is more likely to leak. In that picture

Also as a heads up to DIYers out thee, it is also really bad engineering to have that fill hole in the deck so close to the stanchion base.

Jeff
Show us the math. In what way is it weaker if everything is well bedded together? The bolts are the same strength; the angle is slight less advantageous, but stanchion bolts don't break. The leverage is unchanged. The stainless base is probably stronger than the the alloy base. If there is a difference, I doubt you could measure it.
 

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I emailed Garhauer photos last night and received a response and a contact to call this morning. I called and spoke to Mike and he was very helpfull. They can custom fabricate the part and Mike had some great ideas for the design. We discussed a shim as it makes it easier to fabricate. I have purchased Garhauer products before and they make great stuff so I think I will go for it.

FYI-Sticking a Stainless Steel Stanchion in an Aluminum base for 25 years, even with an insulator seperating the two, is a bad idea. The stanchion is stuck. Pipe wrenches only leave marks in the metal. I'm not sure using heat with a torch will work. Will most likely have to cut thru the base to remove the stanchion.

Thank you guys for your responses.

Brad
I would not use the old stanchion it most likely has creavous corrosion where it is in the aluminum base.
 

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Show us the math. In what way is it weaker if everything is well bedded together? The bolts are the same strength; the angle is slight less advantageous, but stanchion bolts don't break. The leverage is unchanged. The stainless base is probably stronger than the the alloy base. If there is a difference, I doubt you could measure it.
The reason that adding a spacer is significantly weaker than having a geometry where the base of the stanchion base is sitting hard against the deck or toerail (at the points where the bolts are located) would be weaker is that the bolts passing through the spacer are effectively cantilevering between the bearing surface in the deck and the bearing area within the stanchion base. That cantilever places the bolt in bending. So instead of experiencing simple shear or axial tension loads, the bolts are experiencing all three (axial, shear, and bending) Bolts are much weaker in bending than sheer and tension. Given Stainless steels tendency to work harden and fatigue, over time that reduces the strength of the bolts., If the decision was made to use a stainless steel plate, probably a stronger way to address the geometry would be to weld a shim to the bottom of the stanchion base so it stiffened the base plate as well as addressed the geometry issue.

While I acknowledge that this is only anecdotal, on my own boat, I had several stanchion bases were were similarly shimmed, and when I replaced the stanchion bases and bolts, most of those boltys were bent and I was snapped a couple of those bolts where they passed through the shims.

As far as which is stronger the stainless steel base or the aluminum base, properly engineered the stainless steel bases should be quite a bit stronger. But often the baseplates on stock SS stanchion bases are so thin on the stainless steel stanchion bases that they distort and place bending stresses on the bolts as well. That does not appear to ne a great design on the original stanchion bases in the original post of this thread.

Respectfully,
Jeff
 

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The reason that adding a spacer is significantly weaker than having a geometry where the base of the stanchion base is sitting hard against the deck or toerail (at the points where the bolts are located) would be weaker is that the bolts passing through the spacer are effectively cantilevering between the bearing surface in the deck and the bearing area within the stanchion base. That cantilever places the bolt in bending. So instead of experiencing simple shear or axial tension loads, the bolts are experiencing all three (axial, shear, and bending) Bolts are much weaker in bending than sheer and tension. Given Stainless steels tendency to work harden and fatigue, over time that reduces the strength of the bolts., If the decision was made to use a stainless steel plate, probably a stronger way to address the geometry would be to weld a shim to the bottom of the stanchion base so it stiffened the base plate as well as addressed the geometry issue.

While I acknowledge that this is only anecdotal, on my own boat, I had several stanchion bases were were similarly shimmed, and when I replaced the stanchion bases and bolts, most of those boltys were bent and I was snapped a couple of those bolts where they passed through the shims.

As far as which is stronger the stainless steel base or the aluminum base, properly engineered the stainless steel bases should be quite a bit stronger. But often the baseplates on stock SS stanchion bases are so thin on the stainless steel stanchion bases that they distort and place bending stresses on the bolts as well. That does not appear to ne a great design on the original stanchion bases in the original post of this thread.

Respectfully,
Jeff
Shim is perhaps the wrong word, It is a spacer. And the spacer provides uniform bearing and there are no "cantilevers"... much like the condition when you use a washer. A properly fitted spacer does not change the performance/strength of the assembly.
 

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Shim is perhaps the wrong word, It is a spacer. And the spacer provides uniform bearing and there are no "cantilevers"... much like the condition when you use a washer. A properly fitted spacer does not change the performance/strength of the assembly.
Whether you call that plate a shim or a spacer, (a sematic difference without a distinction) the spacer is able to move independently from the stanchion base and the deck. That movement allows the bolt to be placed in bending in addition to the sheer loads and tensile loads that would be present if the baseplate itself was against the deck. .

A washer on the end of a bolt behaves differently than a wadher in the sheer plane. The washer at the end of the bolts helps with bearing by spreading the loads over larger surface it is against. A washer placed in the sheer plane would be worse than a spacer with multiple bolt holes since the spacer in theory distributes the load to multiple bolts at the same time. The washer can allow a substantially larger bending loading on only one of the bolts.

Getting back to the main point, no matter how 'properly' a spacer was sized, it would still potentially place the bolts in bending. That results a much weaker connection, especially over time.

Jeff
 

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Whether you call that plate a shim or a spacer, (a sematic difference without a distinction) the spacer is able to move independently from the stanchion base and the deck. That movement allows the bolt to be placed in bending in addition to the sheer loads and tensile loads that would be present if the baseplate itself was against the deck. .

A washer on the end of a bolt behaves differently than a wadher in the sheer plane. The washer at the end of the bolts helps with bearing by spreading the loads over larger surface it is against. A washer placed in the sheer plane would be worse than a spacer with multiple bolt holes since the spacer in theory distributes the load to multiple bolts at the same time. The washer can allow a substantially larger bending loading on only one of the bolts.

Getting back to the main point, no matter how 'properly' a spacer was sized, it would still potentially place the bolts in bending. That results a much weaker connection, especially over time.

Jeff
Done properly practically this will work. I can only point to real world where my installation has performed fine and better than an aluminum casting.
 

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Done properly practically this will work. I can only point to real world where my installation has performed fine and better than an aluminum casting.
I would agree that you have been lucky so far, just as I was that none of the bolts on my boat broke during use.

But that does not make having a spacer a good idea. In my anecdotal case, I will say that I was very lucky since a coupler of the bolts on my boat snapped when I went to remove them and potentially would have broken had someone hit the lifelines hard plus all of the stanchions with spacers had bent bolts. The bolts on the stanchions without spacers (some in the same position on the opposite side of the boat ) were straight., Your mileage may vary.

Jeff
 

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I would agree that you have been lucky so far, just as I was that none of the bolts on my boat broke during use.

But that does not make having a spacer a good idea. In my anecdotal case, I will say that I was very lucky since bolts on my boat snapped when I went to remove them and potentially would have broken had someone hit the lifelines hard and all of the stanchions with spacers had bent bolts. The bolts on the stanchions without spacers (some in the same position on the opposite side of the boat ) were straight., Your mileage may vary.

Jeff
Sure best to have solid mating surface for load transfer. My windlass has a large teak block which is faired to match the deck camber... For me this was a cost benefit decision. There were no suitable bases which would replace the aluminum ones I had. I believe one had already cracked but I am not sure as it was so long ago. I found a base which matched the holes through the toe rail and I had to drill for the holes in the GRP deck. I don't recall custom options... such as sending an OEM aluminum base to be "replicated" in stainless. This was more than 30 years ago. I may be lucky... I suppose the next owner can upgrade the bases.
 

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The reason that adding a spacer is significantly weaker than having a geometry where the base of the stanchion base is sitting hard against the deck or toerail (at the points where the bolts are located) would be weaker is that the bolts passing through the spacer are effectively cantilevering between the bearing surface in the deck and the bearing area within the stanchion base. That cantilever places the bolt in bending. So instead of experiencing simple shear or axial tension loads, the bolts are experiencing all three (axial, shear, and bending) Bolts are much weaker in bending than sheer and tension. Given Stainless steels tendency to work harden and fatigue, over time that reduces the strength of the bolts., If the decision was made to use a stainless steel plate, probably a stronger way to address the geometry would be to weld a shim to the bottom of the stanchion base so it stiffened the base plate as well as addressed the geometry issue.

While I acknowledge that this is only anecdotal, on my own boat, I had several stanchion bases were were similarly shimmed, and when I replaced the stanchion bases and bolts, most of those boltys were bent and I was snapped a couple of those bolts where they passed through the shims.

As far as which is stronger the stainless steel base or the aluminum base, properly engineered the stainless steel bases should be quite a bit stronger. But often the baseplates on stock SS stanchion bases are so thin on the stainless steel stanchion bases that they distort and place bending stresses on the bolts as well. That does not appear to ne a great design on the original stanchion bases in the original post of this thread.

Respectfully,
Jeff
Obviously. But bolts breaking is not a failure we see in practice.
The reason that adding a spacer is significantly weaker than having a geometry where the base of the stanchion base is sitting hard against the deck or toerail (at the points where the bolts are located) would be weaker is that the bolts passing through the spacer are effectively cantilevering between the bearing surface in the deck and the bearing area within the stanchion base. That cantilever places the bolt in bending. So instead of experiencing simple shear or axial tension loads, the bolts are experiencing all three (axial, shear, and bending) Bolts are much weaker in bending than sheer and tension. Given Stainless steels tendency to work harden and fatigue, over time that reduces the strength of the bolts., If the decision was made to use a stainless steel plate, probably a stronger way to address the geometry would be to weld a shim to the bottom of the stanchion base so it stiffened the base plate as well as addressed the geometry issue.

While I acknowledge that this is only anecdotal, on my own boat, I had several stanchion bases were were similarly shimmed, and when I replaced the stanchion bases and bolts, most of those boltys were bent and I was snapped a couple of those bolts where they passed through the shims.

As far as which is stronger the stainless steel base or the aluminum base, properly engineered the stainless steel bases should be quite a bit stronger. But often the baseplates on stock SS stanchion bases are so thin on the stainless steel stanchion bases that they distort and place bending stresses on the bolts as well. That does not appear to ne a great design on the original stanchion bases in the original post of this thread.

Respectfully,
Jeff
OK, I can see that. The bases got sloppy and the bolts were bent back and forth. I'm guessing there were other contributing factors (egged holes, failed bedding, possibly soft deck).

I can also see that you might not have a choice. In that case, going up one size in bolt should do it, along with solving related issues.

Another solution would be to bond a fiberglass shim to the deck, basically making it part of the deck. No shim.
 

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The reason that adding a spacer is significantly weaker than having a geometry where the base of the stanchion base is sitting hard against the deck or toerail (at the points where the bolts are located) would be weaker is that the bolts passing through the spacer are effectively cantilevering between the bearing surface in the deck and the bearing area within the stanchion base. That cantilever places the bolt in bending. So instead of experiencing simple shear or axial tension loads, the bolts are experiencing all three (axial, shear, and bending) Bolts are much weaker in bending than sheer and tension. Given Stainless steels tendency to work harden and fatigue, over time that reduces the strength of the bolts., If the decision was made to use a stainless steel plate, probably a stronger way to address the geometry would be to weld a shim to the bottom of the stanchion base so it stiffened the base plate as well as addressed the geometry issue.

While I acknowledge that this is only anecdotal, on my own boat, I had several stanchion bases were were similarly shimmed, and when I replaced the stanchion bases and bolts, most of those boltys were bent and I was snapped a couple of those bolts where they passed through the shims.

As far as which is stronger the stainless steel base or the aluminum base, properly engineered the stainless steel bases should be quite a bit stronger. But often the baseplates on stock SS stanchion bases are so thin on the stainless steel stanchion bases that they distort and place bending stresses on the bolts as well. That does not appear to ne a great design on the original stanchion bases in the original post of this thread.

Respectfully,
Jeff
Thank you. I learned something!
 
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