Best Epoxy for...

Blind Nuts

Jamie

I've had excellent results with JB Weld on iron/steel and aluminum is in their list of "works with" as well so I'd give that a shot. Meaning I'd test it with a piece of scrap first.

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

I'm having brain cramps but recall seeing a demo at the hardware store check-out counter. Was a 2 part epoxy that they glued a golf ball to the neck of a pop bottle. Was good stuff. I used it a few times. There's also some MRO products from Devcon

Some of these are so durable that they can be used to fix industrial pump impellers.

PC-7 or JB Weld. Ace has both of them. Art

Some such castings are zinc alloy or magnesium, it's hard to be sure... I'd hand-grind a bit of scrap stock, tap it to make a captive nut, and just use the epoxy to ensure prolonged captivity. This assumes the seamy side of the casting isn't visible.

If it's definitely aluminum, soldering is another option.

Mix up some liquid steel type epoxy and add some silica fibers to it. Adds strength, like "glass filled" plastics.

Prep the surface with a bunch of 0.050" 'holes' spot faced into the mounting face area (or smaller) just deep enough to make anchors for the epoxy.

Or slap a square of fiberglass cloth behind it. A kit with decent epoxy (not the 5-minute stuff) and cloth is around $10.

Eg.

Best regards, Spehro Pefhany

hi, what about getting it welded ? i`ve gotten aliminium casting welded before at local engineering place,..add a bit of weld then drill and tap it ?

mark

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

Clean, degrease, perhaps rough up a tad, and apply whatever epoxy is handy - heck, hot glue might do it.

If you want to do it really well (or "best", as you start out with), hunt up some Armstrong A-12, but that hardly seems like where you need to go for the described use. It does work VERY well.

Rethinking your process. In descending order:

• Blind nut, or bolt from behind. Perhaps put the bolt through a hole and glue from behind.

• Have a welding shop (or a friend with a TIG welder) weld a boss onto your casting, drill & tap that.

• Get some aluminum soldering kit from a welding supply place and solder the bolt on.

• JB weld.

There are products designed for just that purpose, consisting of an aluminum powder combined with an epoxy. I used to use this to fix extrusions (heat sinks) that had scratches and gouges. It looks like aluminum, is machinable like aluminum, and holds well to the base metal.

If you need, I can see if I can find a maker/part number for you, I may have some left on the shelf, but I'm not sure.

"Jim Thompson" wrote in message news: snipped-for-privacy@4ax.com...

I have had good results with Araldite two part epoxy for over 30 years. Ciba-Gigy sold the adhesives to Huntsman, so now I purchase Huntsman Fastweld 10. A search of Araldite has a lot of hits but now they have so many products, I don't know what the original was. So go with the Huntsman Fastweld 10 Rapid setting Epoxy structural Adhesive. For Industrial Use. Huntsman Advanced Materials Americas, Inc

I'm sure you can find somewhere closer to purchase it. Give them a call, maybe they can give a you a local supplier. Mikek

Or this stuff, available under various names from various places:

There are how-to videos in the usual places, some of which show putting a bead of the stuff on the bottom of an aluminum soft drink can. A stick of this and a propane torch are cheap enough that one could practice on some scrap (or a can) to get the technique down -- as well as see how well it may hold.

AnimalMagic wrote in news: snipped-for-privacy@4ax.com:

aluminum doesn't solder well.

you can get the fillers at a boating supply store,probably West products;good stuff.

and allow a week or preferably two for the epoxy to cure to FULL strength.

Sounds like what I need. Manufacturer/part number info would be much appreciated! ...Jim Thompson

Just don't try to have it anodized... Over the years, we've had a few subcontractors that made an 'Oops' when fabricating aluminum parts. Mostly the fault is holes drilled in the wrong spots. Contractor filled them in either with either a weld or some filler and milled them flat again. Barely noticeable if at all on incoming inspection but when they were anodized, very noticeable. Acid etch attacked the filler material much more readily and the result was unacceptable.

Devcon Alumimum Putty (F)

Here's a link:

I've used it several times to repair parts (mostly to fill in damage), have not machined it a lot but what I did do worked well.

Thanks! ...Jim Thompson