Rivet Mandrels

[Quarry Man]

I am starting my boat project next week. I am using 1.5" x 1.5" x 1/8" angle and flat bar. I am using 3/16" x 1/2" rivets. I am confused with which mandrel to use. The options are aluminum and steel. all aluminum is way more expensive, like 3x more. these have steel mandrels but are 36$ for 1000.

 

https://www.amazon.com/dp/B07PRXKML7/?coliid=I3GJ7PUVL66Q5W&colid=16885SQZ4EJN0&psc=1

[Mjmj]

My guess is steel will rust

[Quarry Man]

4 hours ago, Mjmj said:

My guess is steel will rust

are the mandrels removed or do they stay in?

[Catt]

6 hours ago, Quarry Man said:

are the mandrels removed or do they stay in?

 

They stay in but you will be fine with steel.

 

#1: use the correct drill bit

#2: make sure the hole is drilled as close to vertical as you can

#3: buy a rivet grip length gauge 

 

 

[Way2slow]

What am I missing here.  What I bring up with that link is pop rivets.  I would avoid using those in an aluminum boat and if I did, it would only be places well above the water line and on something that didn't have much stress and I could not get an anvil into to brad an aluminum rivet.

Also, as mention, even then they should be the proper length, not just one generic length that's going to leave them sticking up everywhere.

Those things might be ok for putting a lid hing on or some small accessory but not in the structure.

Not trying to be ugly, but it sounds like someone needs to do a whole lot of home work on proper repair of aluminum boats.

[J Francho]

Doesn't sound like a repair to the hull, but building a deck.

 

Part of the mandrel remains on any pop rivets I've used.

[Way2slow]

Yea, when I read the whole post I saw that, but still, he's got to be sure none of those things are anywhere near the water line or below it.

 

I said I would use stainless, because they are much stronger than aluminum, but I would first double check and make sure long term exposure of stainless against aluminum does not create corrosion.  I don't mess with tin cans so not sure about using different metals against aluminum.  I do know you don't want anything galvanize anywhere near it.

[Catt]

With dissimilar metals all that is required is primer &/or a sealant which breaks the galvanic connection.

 

In the aircraft industry all mating surfaces are primed, a layer of sealant applied, & fasteners installed wet.

[Quarry Man]

3 hours ago, J Francho said:

Doesn't sound like a repair to the hull, but building a deck.

 

Part of the mandrel remains on any pop rivets I've used.

correct, I will be joining 1/8" angle and flatbar. Only holes in the boat will be well above the water line. I plan on having 3ish rivets per joint.

6 hours ago, Catt said:

 

They stay in but you will be fine with steel.

 

#1: use the correct drill bit

#2: make sure the hole is drilled as close to vertical as you can

#3: buy a rivet grip length gauge 

 

 

mind explaining what the grip length gauge does?

also, what type of rivets? I was told 3/16" x 1/2" will work fine

 

thanks

[Catt]

3 minutes ago, Quarry Man said:

correct, I will be joining 1/8" angle and flatbar. Only holes in the boat will be well above the water line. I plan on having 3ish rivets per joint.

mind explaining what the grip length gauge does?

also, what type of rivets? I was told 3/16" x 1/2" will work fine

 

thanks

 

Measures the proper length rivet required for the thickness of the material.

 

3/16" × 1/2" rivet

3/16" is the rivet diameter 

1/2" is the maximum thickness this rivet will work on.

 

If your angler & flat bar are 1/8" that's 1/4" total...1/2" maybe a tad long.

[J Francho]

Maybe someone can comment, but I've never used pop rivets for anything structural, like a deck.  Is the angle and flat bar iron?

[WRB]

Do you plan on fabricating the deck frame structure outside the boat then installing the frame? I wouldn't use pop rivets for anything structural, use standard rivets and a river set. Aluminum rivets are better choice for aluminum structure to eliminate any issue with galvanic corrosion. Stainless rivets are stronger but require coating when installed into bare aluminum.

Tom

[Catt]

The pop rivets Quarry Man listed are aluminum rivets with a steel mandrel which is coated to prevent corrosion.

 

The issue with pop rivets is they better be installed properly, with proper hole diameters, drilled as near vertical as possible, & with proper grip lengths.

 

Any rivet performs 2 functions, the rivet swells in the whole & the button head & shop end suck the metal together. This give shear & tension strength.

 

If I were to use any "pop" rivet it would be CherryMAX® rivets installed with a pneumatic gun.

 

[Quarry Man]

4 hours ago, J Francho said:

Maybe someone can comment, but I've never used pop rivets for anything structural, like a deck.  Is the angle and flat bar iron?

aluminum, 6061 structural

1 hour ago, Catt said:

The pop rivets Quarry Man listed are aluminum rivets with a steel mandrel which is coated to prevent corrosion.

 

The issue with pop rivets is they better be installed properly, with proper hole diameters, drilled as near vertical as possible, & with proper grip lengths.

 

Any rivet performs 2 functions, the rivet swells in the whole & the button head & shop end suck the metal together. This give shear & tension strength.

 

If I were to use any "pop" rivet it would be CherryMAX® rivets installed with a pneumatic gun.

 

I will be using a 3/16" black oxide drill bit.

 

I will take extra steps to ensure I drill correctly.

 

is 1/2" rivets too big?

 

would the rivets I recommended work? the cherrymax ones seem quite confusing.

2 hours ago, WRB said:

Do you plan on fabricating the deck frame structure outside the boat then installing the frame? I wouldn't use pop rivets for anything structural, use standard rivets and a river set. Aluminum rivets are better choice for aluminum structure to eliminate any issue with galvanic corrosion. Stainless rivets are stronger but require coating when installed into bare aluminum.

Tom

not sure if I will be fabricating the frame structure inside or outside the boat. I will have precise measurements so either way is a possibility. 

 

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https://www.amazon.com/dp/B07QJZ98C2/?ref=exp_michaellopez_dp_vv_d&th=1

what about #66

[WRB]

The way a pop or blind rivet works is the rivet is placed into the precise drilled hole with the head facing the finished or outside surface. The rivet tool is loaded onto the rivet mandrel shaft that the tool pulls through the tubular part of the rivet until it's tight, then the tool cuts off the mandrel shaft leaving it in the rivet tube. The rivet length isn't critical with pop or blind type, just needs to be long enough to draw tight to form head.

Tom

[Way2slow]

Shoot, just go out and spend about a couple of thousand on a MIG with a spool gun for aluminum or a TIG.  Spend another couple thousand on classes learning how to use them to weld light gauge aluminum and start over again next spring.  Then you can do your little $500 upgrade the "right" way.  Then you would only have to repaint the boat and be done with it.

 

It's amazing with the little DIY upgrades and projects can lead into, ain't it?

 

My daughter drug home a puppy last summer that's now about 70 pounds and destroying the back yard and getting dirt all in the house, (there's a dog door to go in and out as pleases) so I've decided to fence in a area on the side of the house about 35' square.  Thinking a couple hundred dollars of fencing and be done.  Yea, right!  My list of materials just added up to $950 and that does not include railing around the back porch to cut off the path into the back yard and gravel in the path they will take across the back to get to that area.

[Catt]

1 hour ago, WRB said:

The rivet length isn't critical with pop or blind type, just needs to be long enough to draw tight to form head.

 

Length is very critical!

 

To long it will not draw it tight which in turn will cause the river to wallow the hole diameter out.

 

To short it will not have a "shop" end to hold anything.

 

Personally I would weld it but there again down here that would cost you a couple hundred.

[WRB]

Agree Solid rivets and tubular rivets lengths need to be accurate. Pop or blind rivets the mandrel will pull tight with  a rivet + 1/4" longer then ideal length, that isn't critical IMO. Just not a fan of pop rivets but they don't require a lot of skill to install.

Welding is better if the welder knows what they are doing, aluminum isn't all that friendly to weld properly without warping etc. 6061 is a good choice for welding.

Tom

[Catt]

2 minutes ago, WRB said:

Pop or blind rivets the mandrel will pull tight with  a rivet + 1/4" longer then ideal length, that isn't critical IMO. 

 

Good luck with that ?

[slonezp]

2 hours ago, Way2slow said:

Shoot, just go out and spend about a couple of thousand on a MIG with a spool gun for aluminum or a TIG.  Spend another couple thousand on classes learning how to use them to weld light gauge aluminum and start over again next spring.  Then you can do your little $500 upgrade the "right" way.  Then you would only have to repaint the boat and be done with it.

 

It's amazing with the little DIY upgrades and projects can lead into, ain't it?

 

My daughter drug home a puppy last summer that's now about 70 pounds and destroying the back yard and getting dirt all in the house, (there's a dog door to go in and out as pleases) so I've decided to fence in a area on the side of the house about 35' square.  Thinking a couple hundred dollars of fencing and be done.  Yea, right!  My list of materials just added up to $950 and that does not include railing around the back porch to cut off the path into the back yard and gravel in the path they will take across the back to get to that area.

Hobart has a nice welder that can be had for around $400 and youtube videos are free. That being said....There are many different ways to do things the "right way". Money seems to be the biggest obstacle. 

The right way to some might be to last a season and the right to others might be to last a lifetime. We shouldn't confuse the two.

[Way2slow]

I was only joking about welding it. 

A lot of professional fabricators would laugh if you asked if they would weld it for you.  Trying to weld dissimilar aluminum's that are different thicknesses on one of those only being 10 - 12 gauge is not easy and if you didn't repaint it, it would look a poor attempted to camouflage it, touching all the spots up.

Plus welding is not necessarily the best unless done by a true professional that knows how to anneal it when done or it could make it brittle and crack over time.  Not to mention how wavy it might look on flat panels.

 

[J Francho]

18 hours ago, Catt said:

 

Length is very critical!

 

To long it will not draw it tight which in turn will cause the river to wallow the hole diameter out.

 

To short it will not have a "shop" end to hold anything.

 

Personally I would weld it but there again down here that would cost you a couple hundred.

I agree here.  I use six rivets in an old Turkish cymbal to get a sizzle effect (drums, not fishing).  I found aluminum gives a better sound, go figure.  The point is, the rivet tool only pulls the ball at the "hidden end" so far, before snapping off the mandrel on the visible side.  On the rivets I used, the cymbal is pretty thin, less than 1/16" and there's at least 3/16-5/16" play, meaning what Catt says is right: depth matters.  That's how I get a "sizzle" from that old cymbal.  I also know that there are different lengths on the sleeved pop rivets I use to attach accessories to a kayak.  That length is based on how thick the material you're attaching to the hull, and how thick the hull generally is at that point.  Too long a rivet, and what you are attaching will be loose, even though you got a solid pop from the rivet tool.