Filling defects in cast iron

I have a Fobco drill and Myford milling attachment. They both have holes drilled in them, not by me I might add!

The Fobco has one hole in its table approx 5 mm in diameter and 3 mm deep. The Myford milling slide is peppered with small holes at the bottom of one tee slot. They form a group about 1/2 inch in diameter.

As none of these defects are in areas that normally get a lot of use, I was thinking of filling them with cast iron loaded epoxy and then sanding the areas down flush with the cast iron surface.

Anyone got any suggestions for a product to use? I know there will be people who will say it won't work long term. All I can say is that I have used aluminium loaded Devcon, applied as per instructions and it has been bombproof.

Unfortunately Devcon do not make a cast iron loaded epoxy!

Andrew.

P.S. I know it is only cosmetic. but it does irritate me to see such defects.

I successfully repaired similar damage to my drilling machine using araldite loaded with cast iron dust. I made the dust by filing a lump of scrap cast iron, then added as much as I could to some pre-mixed standard araldite without it it getting too stiff. Degreaser the damaged areas, pressed the mix in firmly, then filed back flat when set (24 hours). 15 years later the repairs are still fine.

Mike

Beaumont's egg might be safe to use in this situation?

Since it's not a Bridge you are repairing the Beaumont's egg will be safe enough. or go with Mike's Epoxy and cast iron fillings.

+1 on the epoxy and CI dust method.

If using that method, I would suggest using lacquer thinners or electrical contact cleaner to get the holes really clean and free of any oil or grease before applying epoxy. I'd also recommend wetting the hole thoroughly and completely with a coat of un-filled mixed epoxy just before applying the mixed epoxy with filler. This will give the best chance of a good keyed bond from all the nooks and crannies of the hole to the filled epoxy.

I did this repair about 12 years ago to some errant holes by the previous owner in my milling machine table . The filled holes are still hard to detect and the epoxy shows no signs of pulling out at all. JD

Thanks folks,

Looks like I will be filing some cast iron. With a muscle wasting disease, that is going to take a long time!

Andrew.

Araldite do an "Araldite Rapid Steel" epoxy which according to thisHalfords advert contains stainless steel.

(http://www.halfords.com/motoring/paints-body-repair/adhesives/araldite-rapid-steel-tubes-2x-15ml)

When mixed, it becomes dark grey, very sticky & thick.

Whether or not it is suitable I cannot say as I only used it as a gap filling heavy duty glue to fix a steel piece inside what I assume was a cast steel tube.

Regards,

Peter G. Shaw

Andrew,

Put a piece of cast iron in the lathe chuck and turn as fine as you can go, that will yield plenty of CI dust, but put some newspaper on the shears!!

Thanks Kwil!

No fool like an old fool, why didn't I think of that! Obvious when I think about it.

Andrew.

Hi all, I have had a senior moment, I have drilled the two holes for the spring retaining pins on the wrong side of the cast iron axlebox. (I cannot turn the box round,slight differance) Can I fill the holes in and redrill in the right place or should I fill in and turn the axlebox over, the other three are ok, any advice greatfully received

regards derek

.

I am working with cast iron ATM. By the time I am finished there will be a bucket full.

Send me your address via PM and I will post you a handful.

Nick

Hi Nick I should be ok on the dust, still digging it out of my ENT dept, another senior moment,forgot the face mask, you think I would learn, keep having these moments, but in my seventys I can expect a few.

regards derek

.

Hi Derek,

I was replying to Andrew.  [ edit :- just seen original post date]

But having said that anyone is welcome to some if they have no handy source of their own. - It's only going to end up in the bin.

Nick

Edited By Nick_G on 22/07/2017 13:16:38

I see this is an old thread, but odd no-one mentioned JB Weld.

I used metal loaded epoxy to fill some cosmetic milling marks (too deep) at the base of the slots when I made a t-slotted table. On skimming it stood out 'pale' against the cast iron, but once a bit of neatcut got on it, it blended in nicely. Still there years later.

Neil