How to enlarge existing hole?

[Richard]

I've got this 1/2" plate mounted to back of PTO. I mount my mower to it.

The plate has an approximate 4" hole for the 1000 shaft to poke through and and a (don't know the measurement) 1 1/8" hole for the 540 shaft to poke through. It totally fits around the 540 shaft but it gives me the heebie jeebies that one side of it is too close. (I know that as long as it's not hitting, it's not too close but I'd like it slightly further away)

The 540 shaft is (slightly) but noticeably off center. I'd like to enlarge the hole maybe 1/8" to maybe 3/16"

I currently have bracket removed and in my hands.

I was thinking maybe a stepped drill bit?

Reading up on them, people use them for thin metal, wood.... not seen anything about 1/2" steel so it might not be up to the job.

What's best tool to simply ream out an existing hole a fraction of an inch??

 

[Gordon Gould]

I have done that kind of thing with a hole saw. Find one the size you want. Then take a metal plate, 1/4 to 1/2" say, and make a hole. Then clamp your plate on top of the piece you want to drill out so it acts as a guide for the hole saw. Use a low RPM drill, some cutting oil, and blow out the kerf often if you even have a kerf with just a slight enlargement. I use a rt angle Milwaukee drill or slow drill press. A large 1/2 round file would also work.

gg

 

[Leejohn]

Air die grinder with a barred bit. About a 5 min job.

 

[Diggin It]

I can't really tell what we're talking about from that picture. If this plate can be removed, I'd try a die grinder of some kind. Just grind out the area you need, even if it goes a bit oblong.

You might even be able to do it with a rat tail or half-round file if you have room to work.

 

[AWSubie]

https://images.homedepot-static.com...el-rotary-tool-bits-562-64_400_compressed.jpg
These dremel rotary files work really well even on heavy plate.

 

[oosik]

I have taken a very course round file - chopped it down - chucked it into my Milwaukee 1/2" Hole Hog. Does a reaming job on half inch steel plate real well.

 

[RBLapham]

Buy a reamer of the correct size it will be tapered slightly but will be round. Ream also from the other side will help get rid of much of the taper. I used mine to enlarge some old saw blades to fit my new one. it cut very fast - put in my 1/2 inch drill. They are inexpensive also. https://www.amazon.com/Woodstock-D4...40&qid=1562496807&s=industrial&sr=1-1-catcorr

 

[TractorGuy]

If I see it right the plate is ridged mounted to the tractor right at the shaft so no chance of flex. If it's not hitting I wouldn't worry about it.

Is there some sort of flex coupler to the PTO pump? That alignment would be critical being that close to the shaft.

 

[Richard]

Sorry late to respond.... where to start...

The plate is currently off and in my hands. It DOES mount rigidly to the tractor, I have no reason to think it might flex.

I had a shaft snap and as it snapped, it must have wobbled a bit (?) At the "4:00" position, there is a hot spot and a SLIGHT deformation where the shaft rotated. (shaft is 100% clear of hole when shaft is intact, the breaking of the shaft caused this)

If the shaft is (I don't know) 1 1/8" wide, this must be 1 5/16's wide. It clears but it's close. (you can tell it was well executed and well measured when I had it made.

I've got a 20 gallon compressor. I didn't think of using that to grind it off!!

I've got a right angle (Milwaukee) drill should that need to come into play.

Time to find a grinder bit!!!

Thank you for the thoughts!

 

[Mendonsy]

1/2" plate will take a bit of grinding. You might want to consider taking it to a local welding shop to have them cut the hole out with a plasma cutter.

 

[Gary Fowler]

A carbide barrel bit in a die grinder will make short work of enlarging that hole by 1/8-3/16" after all you only need to remove 3/32" all the way around. With a carbide bit and die grinder, it wont take more than 5 minutes to do. Be aware of the fine slivers of steel coming off and wear good eye protection and gloves. Nothing hurts more than getting those stuck in your fingers/hand/ God forbid your eyes.

 

[Diggin It]

^^ Doesn't appear he needs to go all the way around, just a small area where the shaft is nearest.

 

[Ortimber]

How about a cutting torch or plasma cutter? You could make quick work of this if you need to shave off just a little bit.

 

[Richard]

Tools I have at hand:

Compressor (with small die grinder that is probably better used for polishing small items)
1/2" Milwaukee right angle drill
4" DeWalt grinder
7" Dewalt grinder (too bad I'm doing an inside instead of an outside)

I live 15 miles out of town so it's always a pain to find someone to do things

 

[searcyfarms]

order off ebay free shipping for your right angle drill a reamer/carbide barrel bit and open that thing up!!!

i live 20 miles out and plan my trips accordingly, grew up 60 miles from anything so i have that ingrained in me to make my trips count not to mention we had little growing up and always scraping pennies.

those bits are cheap, i bought a set from harbor freight and they were very inexpensive use them all the time!!! use it in my cordless craftsman drill they cut very well

 

[Scrambler82]

From what I have read all good ideas to enlarge the hole.

Was wonder though, do you have pictures of both the Plate (both sides) and the shaft that goes through it ?
Not that it will change things but just to have a better idea of where you are and what approach "might" be better, pictures can talk if you let them.

Dependent on how critical the hole dimensions are and just how accurate you want the hole to be, the first idea by "gg" sounds the best and cleanest idea... to me ! Yes there is the Machine Shop, either Plasma Cut or Mill the Plate but if things aren't critical a high speed hole saw is quick and efficient.
Making a guide plate to center the hole saw, I've had similar situations and have been caught with my pants down on deciding just how to approach it and now I have a great idea for future events in that arena, thx gg !

Before this the Die Grinder, off the Compressor, worked ok, and a File works but too slow, but a hole saw that you can center on the hole with a jig... to me ingenious !

So I have no suggestions better than what was already used, and my intent of posting was more to get pictures then try to suggest another method, but I found a new way to do my own holes, wood or steel, so I click away from this thread more informed (learned something today) !

Good Luck on the Hole Project, please post up pictures on "where you started" and "where you went" !

Ltr

 

[downsizingnow48]

Everything mentioned will work.
My choice would be a 1" diameter flap wheel, 36 grit. In your Milwaukee drill. That is exactly my favorite setup for this. It will be almost as fast as the die grinder but creates dust instead of nasty needles that fly everywhere.

 

[Big Barn]

Everything mentioned will work.
My choice would be a 1" diameter flap wheel, 36 grit. In your Milwaukee drill. That is exactly my favorite setup for this. It will be almost as fast as the die grinder but creates dust instead of nasty needles that fly everywhere.

And way more relaxing.

 

[MossRoad]

I've got this 1/2" plate mounted to back of PTO. I mount my mower to it.

The plate has an approximate 4" hole for the 1000 shaft to poke through and and a (don't know the measurement) 1 1/8" hole for the 540 shaft to poke through. It totally fits around the 540 shaft but it gives me the heebie jeebies that one side of it is too close. (I know that as long as it's not hitting, it's not too close but I'd like it slightly further away)

The 540 shaft is (slightly) but noticeably off center. I'd like to enlarge the hole maybe 1/8" to maybe 3/16"

I currently have bracket removed and in my hands.

I was thinking maybe a stepped drill bit?

Reading up on them, people use them for thin metal, wood.... not seen anything about 1/2" steel so it might not be up to the job.

What's best tool to simply ream out an existing hole a fraction of an inch??

:confused3:

If it ain't broke, don't fix it.

 

[Rebeldad1]

You want to take off so little in one spot...
Mark it with a felt tip marker where you need the material taken off and use a round file like a chainsaw file. Takes a little work but its free.