This site uses cookies to maintain login information on FarmallCub.Com. Click the X in the banner upper right corner to close this notice. For more information on our privacy policy, visit this link:
Privacy Policy

NEW REGISTERED MEMBERS: Be sure to check your SPAM/JUNK folders for the activation email.

Tapping Cast Iron

The Cub Club -- Questions and answers to all of your Cub related issues.
Forum rules
Notice: For sale and wanted posts are not allowed in this forum. Please use our free classifieds or one of our site sponsors for your tractor and parts needs.
mymariah
10+ Years
10+ Years
Posts: 41
Joined: Tue May 25, 2004 6:35 am
Location: Iowa
Contact:

Tapping Cast Iron

Postby mymariah » Wed Feb 09, 2005 2:39 pm

So I got my tractor back after taking to a welder to get the broken holes out (the story about plowing snow and busting the holes out that hold the alternate drawbar). Now we have to drill out the holes, and tap them. I'm looking for suggestions on drilling cast iron, and tapping the holes. The first suggestion I got was to predrill a block of wood and use that as a starter for the tap so that it gets started straight. Any other suggestions would greatly be appreciated. Soon I'll get some before and after pics posted.

SPONSOR AD

Sponsor



Sponsor
 

User avatar
beaconlight
10+ Years
10+ Years
Posts: 7703
Joined: Thu Aug 19, 2004 2:31 pm
Zip Code: 10314
Location: NY Staten Island & Franklin

Postby beaconlight » Wed Feb 09, 2005 2:52 pm

If i remember correctly lard is the preferred lubricant when drilling cast iron, or at least it was 50 years ago when i did that stuff. I question how much drilling of cast you will be doing and how much weld you will be tapping. Start the tap turn it in, back out to clear chips and back in again, out again etc. With a hand tap you don't have the cooling and lub of a constant stream of cutting oil.

Bill
Bill

"Life's tough.It's even tougher if you're stupid."
- John Wayne

" We hang petty thieves and appoint the great ones to public office."
- Aesop

User avatar
Scott
10+ Years
10+ Years
Posts: 1194
Joined: Sun Dec 26, 2004 7:09 pm
Zip Code: 02769
eBay ID: scottdarowski
Tractors Owned: 48 Cub
55 Cub
62 CCO
63 CCO
70 JD 112
Location: MA, Rehoboth
Contact:

Postby Scott » Wed Feb 09, 2005 3:16 pm

Me and my friends used the wooden block trick when we built the wooden cap on his nissan pickup
Image On To Bigger Things

User avatar
John Niekamp
10+ Years
10+ Years
Posts: 757
Joined: Tue Apr 06, 2004 9:41 pm
Zip Code: 62301
eBay ID: jniekamp66
Location: Quincy, IL

Postby John Niekamp » Wed Feb 09, 2005 8:05 pm

mymariah,

First comes to mind is a product that is called "Mystic Metal Mover" However, when the banned went on by the government to help eliminate the depletion of the ozone cause by chlorofluorocarbons, or CFCs. CFCs this product was no longer able to be made. They did come out with the Next Generation, but it's not nearly as good as the original. There is also a product called "Tap Magic" which is also good. The MMM was the best in my opinion, and I have one can left that I use only for stainless steel tapping.

Now, more than likely, you will probably not have access to these items that I have mention, unless you know someone who may have them.

I have heard the old timmers at work using a few drops of kerosene too. I have never tired it myself, I use KROIL or WD40 most of the time, but as Bill has stated clean out the hole out often, keep it free from chips. Also use a good sharp tap and not cheap one from someplace like Wal-Mart. go and get youself a good quality one. It may cost more, but in the end it will save you, plus you will have it for many years to come.

I just know I will get myself into trouble and a big debate for saying this, but I wouldn't even buy one from Craftsman. I really like the Craftsman line of tools, but I don't care for their taps (and I even have a set). They work fine for chasing threads, and tapping a few holes, but in my line of work, I can't trust them. JUST MY PROFESSIONAL OPINION !!!

NOW, I also relize that not everyone does this all of the time, so if you don't have access or want to spend the money for a good grade of tap, LET ME know and I will send you one that you can borrow. I have some that we use in our very high speed CNC milling machines, that are outstanding, and works just as well with hand tapping.

I have a small block of tool steel, heat treated with a series of differnt sized holes for each of the correct drills and tap sizes that I use for hand drilling and tapping, that works real well. I don't see what would be wrong in using a piece of hard wood, doing the same thing.

Hope this helps,

John Niekamp

PS: beaconlight I think that Lard or even grease would be good for two reasons: 1, the lubricating factor and 2, the chips would stick to the tap and when you broke a chip you could bring them back out with the tap and clean them off easier, then re-apply which ever. I have used grease for heli-coillng spark plug holes and works great for keeping chips out of the cylinder.
Machinist
1954 Regular F-Cub "PRB" (Puckett's Rust Bucket)
1955 International Cub LoBoy "SQUATTY"
1954 3800 series Chevrolet flat bed grain truck "Ole Ben"
1975 Case 1737 skid-steer

Ron L
10+ Years
10+ Years
Posts: 661
Joined: Wed Mar 05, 2003 9:09 pm
Zip Code: 18603
Tractors Owned: 1948 Cub
1955 Cub
Location: PA, Berwick
Contact:

Postby Ron L » Wed Feb 09, 2005 9:31 pm

mymariah. If your only drilling & tapping a few holes in cast iron, don't worry about coolant. The worst thing with cast iron is hard particles or sand sometimes in the cast. Chips should break into small particles with no problem. Your wood block to keep the tap straight to start is a good idea. I have aluminum square blocks to do this. If I remember your problem area, the size is 5/8 - 11. This will take a good size tap wrench, but cast iron usually cuts like butter. Start with a long lead thread tap and finish with a bottom tap.

If your welded holes are not completely filled up, it may be rough going with the drilling. With that size tap, you should use a few undersize drills first, anyway. Makes the job easier.

The guys gave you some good ideas. However, no coolant would suffice. Kerosine would be good on drilling and tapping aluminum, but I would hesitate on cast iron. If your worried about heat, just use water.

Now, we're talking "cast iron" here! Hope this helps................
Ron

User avatar
John Niekamp
10+ Years
10+ Years
Posts: 757
Joined: Tue Apr 06, 2004 9:41 pm
Zip Code: 62301
eBay ID: jniekamp66
Location: Quincy, IL

Postby John Niekamp » Wed Feb 09, 2005 10:21 pm

Here ya go, I just found it right out of my Machinist handbook.

CAST IRON:

Drilling: Dry, Air jet or Soluble Oil
Threading: Dry, Sulphurized oil, Mineral oil or Lard
Turning: Dry, Soluble oil.

Looks like "DRY" is best in all three cases.

We keep spray bottles of machine coolant all around the shop, called Hocut. It's smiliar to the soluble oil mixed with water. You know it's that milk looking coolant you see in machines. Keep it handy for things like this.

Oh yeah, in any case, REMEMBER the safety glasses, I know I probably didn't have to tell you that, but it never hurts to remind folks.

John
Machinist
1954 Regular F-Cub "PRB" (Puckett's Rust Bucket)
1955 International Cub LoBoy "SQUATTY"
1954 3800 series Chevrolet flat bed grain truck "Ole Ben"
1975 Case 1737 skid-steer


Return to “Farmall Cub”

Who is online

Users browsing this forum: No registered users and 31 guests