Drill press hole filling with ARC

[TheJay]

I have a 1981 Draper drill press and there is a hole in the side of is that I tried filling using 7018 rods. I think it's cast iron around 3-5mm thick and it doesn't like the heat so it's cracking around the areas welded. Initially I placed a piece of 1.5mm thick mild steel behind the hole, welded to that and then built up layers. I managed to cover the whole thing. Then I started grinding to get it level and there were areas that weren't full, so I grinded them out and started filling again. After spending many hours trying this approach, I think it might be time to try something else.

I want it to be a structural repair and then want to be able to mount something on the outside.

What approach would you take?

 

[dave h 2]

You don't use steel rods on cast iron for a start

 

[500e]

Cast is very prone to cracking, you have new cracks propagating from the original metal .
Use the correct rod for cast as @dave h 2 said. look up welding cast iron on Google
Did you pre heat the casting and keep the heat in when finished to allow the casting to cool slowly.
Personally I would have heated casting, TIG braised and then wrapped in fire blanket to cool.
Also drill the ends of the existing crack 3mm helps stop them, what happened to casting to need a hole cutout, was there something welded on there?
Even with all that you can get HAZ cracks.
Others on here with a lot more experience will explain further I expect

 

[TheJay]

Thanks for your replies. I'm not sure exactly, when I got the machine someone had epoxied an on/off button over the top but I am updating the electrical components and the hole would be visible.

I don't think I have the right equipment to heat up the whole part, is there anyone near Worcester who does have it? Or perhaps someone nearby has a way to cast a piece into the hole. Maybe there is another method that doesn't require heat but is still an effective structural repair?

 

[roofman]

I would be taking off all that weld, bolt a plate over it with countersunk machine screws tapped into the casting. The way your going there its going to crack its self to oblivion, remember your handicapped by the fact its Chinesium casting too.

 

[TheJay]

Yeah, I was considering taking off all the weld given that the crack is moving outwards. I want to try and make the finish flush, what's the best way to do this instead of bolting a plate on top of the casting?

 

[TheJay]

*Avoiding bolting a plate in front of the casting

 

[TheJay]

Alternatively, would it hurt to use JB Weld to fill in the gaps and make a v groove in the areas where there is cracking to fill in with JB Weld too? What I am trying to say is, what are the chances if the welding is left in situ as it is that the damage will get worse over time either from expansion/contraction of different materials or rusting?

 

[123hotchef]

what do you want to mount on the outside?

 

[TheJay]

 

[123hotchef]

that DOl would have covered the hole, out of sight out of mind!

 

[TheJay]

Kind of, there was a 3cm gap along the side. So which way shall I go to get it flat? I want to repaint it.

 

[123hotchef]

JB weld gets my vote

 

[TheJay]

If everyone thinks J B Weld is the best option, should I be doing any prep before filling? Is it important to make grooves?channels where the cracks are/drill holes at the end of cracks and is there anything else I should do?

Should I use SteelStik putty?

 

[500e]

Why not drill countersunk holes and fit a plate inside, then fill with JB and sand

 

[addjunkie]

Belzona 1111

 

[6ply]

Why not drill countersunk holes and fit a plate inside, then fill with JB and sand

That will use more JB Weld than the thing is worth.

If this were my drill, I'd cut out the badly welded section with an angle grinder, putting it down to experience, then screw a plate on top. It will look just fine.

 

[TheJay]

Belzona 1111

Never heard of it, looks like good stuff but that's a lot of money!

That will use more JB Weld than the thing is worth.

If this were my drill, I'd cut out the badly welded section with an angle grinder, putting it down to experience, then screw a plate on top. It will look just fine.

What thickness of plate would you use? Would you use mild steel?

 

[addjunkie]

That will use more JB Weld than the thing is worth.

If this were my drill, I'd cut out the badly welded section with an angle grinder, putting it down to experience, then screw a plate on top. It will look just fine.

Just looked again……skip that step, go straight to scrap skip, then go online and source new cheap oriental drill press!

 

[addjunkie]

Never heard of it, looks like good stuff but that's a lot of money!

It is superb stuff. You get what you pay for, often used to extend the life of many high value components, such as 5million dollar pumps! Can be drilled, tapped, machined!