Fix a miss aligned hole

[joegreen]

I have drilled 4 holes (1/4" in diameter big) in a 1/4" thick steel plate. Then I plan on using countersink drill bit so that I can flush the bolts with steel plate. One of the holes is misaligned by almost 3/4 of the drilled hole. How do I fix this? Should I use the J-B weld to fill the misaligned hole and then drill a new hole. New hole will be partially through the J-B weld. Will it work? I do not have welding equipment or experience. Any suggestions?

 

[rons]

If you do that then it depends on the orientation of that steel plate in the assembly.
The JB Weld section should not be stressed on.
I don't remember the last time JB Weld worked for me. For cosmetic stuff it's ok.

 

[tylersteez]

I would just start over. 4 1/4" holes in an assumably small 1/4" piece of plate is peanuts. youll waste more time correcting this mistake instead of just drilling 4 new holes.

JBweld is only good for cosmetics, low stress plastic pieces, or just general adhesion needs IMO. I've never had it be even slightly useful in anything more than that.

If you were to weld this hole shut, you would have a hard spot where the weld material meets the steel which makes drilling the new hole right on that line very difficult. Usually people drill out larger than they need to before welding so the new hole can be fully inside the weld

 

[joegreen]

Thank you so much for your advice. I won't waster only on J-B weld. The plate is fairly big in size 28.5" x 16.5". I couldn't use drill press because it's so big in size and heavy. I used cordless drill and I guess the drill bit wandered off on this one hole. I had a plate cut by a shop. I'll see if I can drill a bigger hole and use a bigger bolt.

 

[Limy Sami]

Thank you so much for your advice. I won't waster only on J-B weld. The plate is fairly big in size 28.5" x 16.5". I couldn't use drill press because it's so big in size and heavy. I used cordless drill and I guess the drill bit wandered off on this one hole. I had a plate cut by a shop. I'll see if I can drill a bigger hole and use a bigger bolt.

Tip - get a piece of flat steel at least the thickeness of the hole diameter you want, drill a hole in said piece and clamp it over the misaligned hole in the correct position to guide the larger drill

 

[deltap]

If you only have hand tools, you can move the hole with a small round file like a chain saw file. Just have to be patient, it will take a while. Or drive a piece of steel in the existing hole. File flat with plate. Use a center punch to relocate the hole. Drill 1/8 hole and follow and follow with 1/4. All this extra mindless work will give you time to wonder why you didn't take more care with the original hole.

 

[tylersteez]

yeah if its not a critical part then I'd try to just file out the hole, you might have a hard time countersinking this oval'd out hole afterwords though.

When drilling, use a center punch on the hole location to give the drill bit something to locate itself with first. this will keep your drill bit on point while it starts to cut into the steel. after that, as long as you hold the drill straight you will have the hole where you want it.

 

[Billtodd]

Rivet or peen a steel plug into the hole grind of file flat and redrill

 

[michiganbuck]

If you drill the hole where it needs to be will the countersunk bolt head cover the error? Can you make the patern with all holes taking some of the error to even it out with a larger clearance hole.
Plug the hole with a welded in plug.
Just for looks JB migh wotk if there is no pressure on it.

 

[Gordon Heaton]

Since you have no welder, you can also simply drill the bad hole to size for tapping, LocTite a fine-thread screw in there and grind flush. Then you can drill in the proper place. If the piece is subject to high temps you can drill/tap for a tapered pipe plug instead of using LocTite. You are far enough off location that the plug will stay in place when the correct hole is drilled.

 

[joegreen]

Here is what my project is. I'm a woodworker. I'm replacing the small table of my scroll saw with this bigger table. When I say table, I mean just the steel plate, there are no legs. This steel plate is held by 4 countersunk bolts to the saw. Usually I cover the table top with a magnetic sheet of vinyl so that wood pieces slide smoothly and protect the table. I've never drilled a hole in steel in my life before. I used drill press to a scrap piece of metal and it was lot easier. But I soon realized that because of weight, size of the plate and location of the holes on the plate, cordless power drill was the only other way. So I used DrillMate from Milescraft with power drill. I have used DrillMate only once or twice and I hate it. So a combination of all together resulted in one misaligned hole. I'm going to try with three bolts instead of 4 and hope I don't get too much vibration when the saw is on. This steel plate won't be bear any heavy weight/pressure or heat. Thank you very much for all your helpful suggestions.

 

[GregSY]

It's more difficult to help you since you have not listed your location.....but for the time being, let's assume you are located in an area where there is electricity within 30 miles. If that is the case, we know there must be someone with a welder within that 30 mile radius. Find that person and have him - using his welder - to fill the hole with molten steel. Then, grind it flat and redrill the hole properly located. At that point, your life will go on and you can spend no further time trying to come up with complicated and half-assed repair methods.

 

[BT Fabrication]

weld, grind and redrill...

 

[projectnut]

Not that I've ever been in the same situation, BUT the cure for the problem we had was to drill and bore the hole to 1" in diameter. Turn a plug slightly oversize and press it in the new hole. Weld both sides, and cleanup with a mill. Then redrill the hole in the proper place.

It was a real PITA, but the part was a large 1 1/2" thick 316 stainless plate. It was far too expensive and time consuming to duplicate it. When the job was finished you couldn't tell where the repair was made.

 

[rons]

This steel plate is held by 4 countersunk bolts to the saw. Usually I cover the table top with a magnetic sheet of vinyl so that wood pieces slide smoothly and protect the table.

Since the plate is going to be a mount for a scroll saw the choice of repair is not that critical. Just one plate smack against another plate (scroll saw base).
If you used some solid washers the thing would be fine.

 

[WizardOfBoz]

I suspect that if you use a file to enlarge the hole and counter sink the new hole, you will have a workable setup for a scroll saw table.
If your hole is 3/16 off and you try to use a larger bolt, you have a couple of problems. First, you need nearly a 5/8 inch hole to ensure centrality to the original mounting hole. Is that feasible? Next, the countersink for a 5/8 bolt is going to require a much deeper plate than the 1/4" thickness you have.

One think I suspect that you want is a very flat table. Welding messes that up by thermal warping.

Check the plate now with a ruler or (if you have it) a straightedge. Is it flat? If so, I'd just file out and countersink the filed hole. If not, you may want to find a new plate.

And the process for drilling holes in steel plate with a hand drill are
1) locate the hole with a prick punch (skinny punch, gentle hit generally for more precision, may not be necessary)
2) enlarge the hole with a center punch (harder hit)
3) drill a pilot hole with a small diameter bit. Ensure placement.
4) enlarge the hole to your desired size.

Good luck.

 

[SeeFair]

I would drill four new holes. Consider the first 4 practice.

 

[EPAIII]

You don't weld. I doubt that JB Weld would be hard enough to keep the drill bit centered properly when drilling into the combination of steel and epoxy. The drill bit will just wander into the epoxy and you will be right back where you started.

My first choice would be to take it to a welding shop and let them fill it and grind it flat. Then drill and countersink at the correct location.

Second thought would be to take the trouble to support and clamp it tight on the drill press table and put the countersink in the correct position. Then use the bolt clearance size drill bit to ensure the bolt can follow the countersink. Use a screw machine length drill bit to minimize any tendency to wander.

Of course this depends on the location of the hole relative to the nearest edge and the swing of your drill press. A mag drill could do the job, but I bet you don't have one of those either. Perhaps this would justify that purchase?

Third idea: Enlarge the hole with the next larger tap drill size and tap the hole. I would use a fine thread if possible so that there will be a maximum number of threads in the plate. Insert a threaded plug made of steel that is about as hard as your plate, with epoxy on the threads to hold in in place and use a punch to distort the threads on both sides before the epoxy hardens to create a mechanical lock as well. Fill the punch marks with epoxy. When the epoxy is fully hardened, grind it flat, drill at the correct location, and add the CS. This should be almost as strong as the welded version.

Most good hardware stores will have bolts in various hardness grades and fine or coarse threads. The good ones will also have taps and tap sets but McMaster would be a better place to buy taps and tap drills.

I have drilled 4 holes (1/4" in diameter big) in a 1/4" thick steel plate. Then I plan on using countersink drill bit so that I can flush the bolts with steel plate. One of the holes is misaligned by almost 3/4 of the drilled hole. How do I fix this? Should I use the J-B weld to fill the misaligned hole and then drill a new hole. New hole will be partially through the J-B weld. Will it work? I do not have welding equipment or experience. Any suggestions?

 

[john.k]

It will probably work OK with just 3 bolts ...if not ,then file the hole to suit .......you could then grind the countersink ,or if no grinder , cut it out with a chisel .....a small half round chisel should make short work of it.

 

[technocrat]

Call yourself a fitter and file the hole out to the right position. Curse the machinist for drilling the hole in the wrong place. Start cutting wood like nothing happened.