# Best way to glue aluminum to cast iron



## empty5853 (Oct 6, 2009)

Hello,
What is the best epoxy/glue to use to attach a piece of aluminum to cast iron.

Thanks.

Mark T.


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## TheFridge (May 1, 2014)

Depends on the application I guess.


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## CajunWoodArtist (Oct 27, 2015)

West System epoxy


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## MrUnix (May 18, 2012)

Like the Fridge sez… depends on the application and what kind of force it will have to withstand. Epoxy would probably hold it on, but I doubt it would take much stress… which would really need one or more of these:








Or the ever popular (among manufacturers) drive screw:









Cheers,
Brad


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## Dark_Lightning (Nov 20, 2009)

Why do you not want to use mechanical fasteners?


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## jamesbond007 (Jan 3, 2012)

J B Weld


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## dschlic1 (Jan 3, 2013)

To increase adhesion wet sand both surfaces with the epoxy applied. This does two things: breaks down any surface oxidation and roughens the surface. Learned this trick in boat building.


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## empty5853 (Oct 6, 2009)

Thanks for all the replies everybody. I appreciate it.
Here's what I'm looking to do. I should of explained it in my first post.

I need to attach an aluminum miter track to a cast iron router table. I know you can drill and tap cast iron but this is an old table over an 1" thick and my "drill & tap" experience for cast iron is limited. The table is 27" wide so I'm guessing with holes needed every 4" - 6" for #6 machine screws. Well you can do the math. Lots of holes with the potential for snapping off a tap or drill bit. Been there done that. It's no fun.
I thought of taking the table to a machine shop and having them do it. They have the equipment and expertise to do it pretty easy I would think
The problem is the top weighs a ton. That's why I was thinking epoxy.

I'll have to think about another way to do what I want to do. I do believe you've all hit on my only (2) options. Epoxy it in or drill and tap it.

Take care and thanks again.

Vr
Mark T.


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## MrRon (Jul 9, 2009)

I would definitely drill and tap. It's not that hard to do. Just place your aluminum track where you want it and clamp it down. Since you want to use # 6 machine screws, first drill # 36 holes through the aluminum and the cast iron. Remove the aluminum track and tap using a #6-32 HSS tap. Don't use a cheap carbon steel tap (too easy to break). open the holes in the track with a #28 drill or a 9/64" drill. Countersink the holes and you are done. When you tap, just try to keep the tap as perpendicular to the surface as you can; take a turn then back off 1/2 turn and keep repeating. Use the shortest machine screws you have. At 32 threads per inch, 6 threads penetration is adequate. If the cast iron top is thin enough, like 1/4" or less, use a starting tap and tap all the way through. If it is much thicker, you will have to go the 3 tap way, starting with a starting tap and finishing with a bottoming tap. Lubrication isn't necessary with cast iron, but keep the hole clean by compressed air or a magnet.


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## Bluepine38 (Dec 14, 2009)

If that table really is 1" thick. ask a machine shop what it would cost to machine a miter track in the table.


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## 000 (Dec 9, 2015)

How about drilling a hole and using a nut on the other side?


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## 9x9 (Jan 2, 2015)

3M 5200 ---takes 7 days to fully dry / cure

rough up / scratch both surfaces before if can


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