Making oval holes round.

[orezok]

The ripper shank holders on my tractor have ovaled out due to use. Currently the pins are 1/2" and I want to upsize them to 5/8". The shanks are already 5/8" and show no wear. I tried drilling them, but the drill bit catches.

I considered laying some weld to get them closer to round. A 5/8" tapered reamer would probably do the trick, but that's $50.

Any ideas what would work best.

 

[bullbreaker]

The drill bit like the one on the right should work but can't think of name rite now. You don't have to buy whole kit just one for size you need.

Boone

13/16 in. 1-3/8 in. 1/16 in. Increments 10 Hole Sizes Enlarging Step Drill #21-10221 at The Home Depot

 

[Rustyiron]

How about a new hole either above or below the "egged out" hole?

 

[puckgrinder85]

Problem is with the step drill is material thickness. You'll end up using the next step size to finish the current sized hole, they arent really made for metal over maybe 1/4 inch. The steps are only 1/4 or less deep.


To me it looks like the hole is bigger than a 5/8 pin would be as well. I'd do one of two things. Either weld the correct size bushings on both sides of the hole (if possible due to implement hookup) this would be the easiest and only requires a welder

OR

I'd make one thicker bushing and cut the hole big enough to fit the bushing in and weld in the new bushing all together.

 

[MichKubota]

Use metal guide plate to hold drill in place while cutting over sized hole.

Step 1 - Cut a piece of 1/8" thick metal so it fits in area over hole.

Step 2 - Put small pilot hole in this new piece of metal in location you want new hole.
(note - You just want a small pilot hole. Don't make hole too big or you will end up with same issue you have today).
Step 3 - Clamp or temporarily weld this new piece of metal in place.
Step 4 - Using pilot hole as guide, drill new over-sized hole going through both the new metal and old metal.
Step 5 - Remove clamp or cut weld to remove temporary metal guide plate.

 

[Soundguy]

[yep.. torch it out for a hd bushing.. drive bushing in.. weld in from both sides.. grind flat.

BT DT easier than reaming or drilling or welding and drilling.

works better than plating a piece on either side tofix the diameter..

QUOTE=puckgrinder85;3129943]To me it looks like the hole is bigger than a 5/8 pin would be as well. I'd do one of two things. Either weld the correct size bushings on both sides of the hole (if possible due to implement hookup) this would be the easiest and only requires a welder

OR

I'd make one thicker bushing and cut the hole big enough to fit the bushing in and weld in the new bushing all together.[/QUOTE]

 

[Trials]

The ripper shank holders on my tractor have ovaled out due to use. Currently the pins are 1/2" and I want to upsize them to 5/8". The shanks are already 5/8" and show no wear. I tried drilling them, but the drill bit catches.

I considered laying some weld to get them closer to round. A 5/8" tapered reamer would probably do the trick, but that's $50.

Any ideas what would work best.

I like the 5/8" taper ream idea seeing as the shanks already have 5/8" holes.
my 5/8ths taper ream is roughly a hundred years old so I'm not sure how much grandpa paid for it :I

If it had to be 1/2 inch holes; I would weld plates on both sides with nice clean holes pre drilled in them

 

[mikehaugen]

perhaps try this... weld or clamp a plate on the same plane at the brace, then rent a mag drill and use either an end mill or annular cutter to cut the hole out to a larger size, then use some kind of bushing. You could also put a piece of brass behind the hole and fill it in and grind it smooth and start from scratch.

 

[radioman]

If I had to use what's on hand - I still use the step drill bits. I would only drill to the 5/8 size that pops in on top. Once correct hole is started , you should be able to use a regular 5/8 bit to finish drilling since the step drill bits are great for "centering the hole". Using a thick plate with predrilled 5/8 hole clamped on before using a regular bit after starting hole with step bit is a good idea.

 

[orezok]

OK, here's my plan thanks to several of you. I'm going to round up the hole first with a step drill. I've ordered a 5/8" bridge reamer to complete the process. Finally, I'm going to weld in some shims per the attached to take the load off the pin. This should result in a permanent fix.