Drilling and Tapping a Cast iron piece

[Tony H]

The front of my tractor/backhoe has a Cast iron piece Right in the very front. I'd like to drill and tap a few 1/4" holes to put a small " brush bar". Is there something Taboo about doing this?

The Front Cast section on my tractor is often seen on the back of Skidsteers and excavators as counter balance. that's what I'm talking about drilling and tapping.

 

[OldandWorn]

Cast iron drills and taps nicely. Make sure to reverse the tap and/or clean the hole often as the chips are small and can bind the tap up. Also work it dry with no lube.

 

[Tony H]

Work it dry? wow, I have never threaded anything dry.
I'm new to tractors so Although I am very mechanically inclined.. I keep asking dopy questions. I never know when someone might say "No, that counter weight is a major structure and should never be touched." I realize it actually is structural But I didn't know if drilling it with a few smaller holes would have had knowledgeable yelling at me.

Thanks.

 

[Delmer]

Drill it dry, the carbon in cast will lubricate the bit and if it's too lubed the bit won't bite. Although with a good 1/4" bit you should be fine either way. I don't think it would hurt to thread it with oil, or a spray lube with a straw to blow the chips out as you go.

 

[Tony H]

Got it. Yeah I will lube the Tap and keep backing it out to clear the Chips off the tap.

Thanks

 

[Multiracer]

Drill your holes at the correct size and 1/2" deeper than you need. Find a good HSS "spiral point" tap. You will be amazed !

 

[chroniekon]

Chart says #7 size drill bit for 1/4-20 course and #3 drill bit for 1/4-28 fine.

 

[Tony H]

Thanks. As I said.. I know what I'm doing as far as Drilling and tapping, I didn't know if there was a reason I shouldn't be 'assaulting' this Front piece on the tractor.


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[wrangler]

I think 1/4 bolts would be small for that application.I would go 3/8 or 1/2 inch.It doesn't take much to shear or twist off a 1/4 inch bolt.

 

[Tony H]

I think 1/4 bolts would be small for that application.I would go 3/8 or 1/2 inch.It doesn't take much to shear or twist off a 1/4 inch bolt.

Yeah, Probably up that size. I haven't drawn it up yet.. just asking the tapping question before getting too deep