Tapping Cast Iron

[GVA]

1 Left hand drills not needed for through holes... Right hand drill will grab (if loose enough) and run it forward and out the other side.
2 I agree with d.n.f. Cast is the easiest of any metal I've ever had to tap.....
3 You don't have to buy a whole tap and die set... just the tap you need and appropriate drill. Don't skimp, buy a quality tap
On a side note...............
If they used the self drilling screws to attach the flue collar like almost everyone does............ I would just drill straight through them and then start fresh with a larger size... Though they are a cheap metal and not really good for the heat they are seeing....but they drill easy ;-)

 

[begreen]

I broke several bolts off when rebuilding the 602. It was easy to drill them out and re-tap them. Took all of about 15-20 minutes. The 602 had 8mm bolts if I remember right. I got a cheap tap handle and the single tap for less than $15.

 

[Homesteader]

Thanks to everyone who helped me out here. You were right, it was a piece of cake. I didn't retap or try to remove the bolts. I just grinded them down flush, punched and drilled all the way through with a series of carbide bits for a 1/4 bolt. If the stove were in pristine condition. I would have tried keeping it as original as possible by tapping or removing the bolts. Last night was chilly and damp so I stayed there and burned overnight. Everything was tight and the creosote from my first burn was gone when I checked this morning.
The hearth pad got pretty hot under the stove. The heat shield on the wall stayed ice cold, the clearance is almost 2' from the side of the stove. I can't get the stove any closer than that but there is a lot more usable floor space. I'm going to add some thermal mass to absorb the excess heat under the stove.

Life is good again.....

 

[d.n.f.]

. I'm going to add some thermal mass to absorb the excess heat under the stove.

Life is good again.....

A cat works well.

 

[FN_9]

Glad to hear it worked out for you.

 

[Homesteader]

A cat works well.

Hmmmm... I don't like cats. I got a dog! Would she work? j/k

 

[nhimack]

So drilling straight through the bolt and into/through the cast iron won't be a problem?

LOL sorry I've been at drilling out 2 screws/bolt in the same area on a VC Vigilant to great frustration. and many drill bits. I started smaller, tried the easy out (ya right easy my ..) the idea is to drill and tap the holes. Right now, on Hardware stores advice, I'm dulling up a cobalt bit, not sure if there is something that drills out the bolts better as it is a slow process to say the least

Ian

 

[begreen]

Be sure to put a drop of oil on the drill bit and in the hole before drilling. Oil will help keep the bit cooler. I used a fresh bit for drilling out the holes. One bit did several and I still use the bit today. Use oil on the tap as well.