Repairing egged out hole

[dante2]

I have a pair of brackets that are close to 20 years old and 640+ hours of service on a mower deck. The bracket is discontinued and unavailable in this universe. The hole originally was 7/8" and accepted a bushing and bolt through it. My only option is a repair of the oblong hole. Can I use a 7/8" brass bushing and fill the gap back in with a mig welder? My plan was flat copper on the table and clamp the bracket over that. Then clamp the brass bushing to the original intact edge and fill the oblong gap. Am I going to have a problem with the brass sticking? Any thoughts or suggestions are greatly appreciated. TIA

 

[cvairwerks]

Just weld the entire hole up and then redrill. Way faster and easier.

 

[bwringer]

I think you'll melt the brass bushing, if you're talking about welding with the bushing in place.

I'd just locate the center as best you can, then fill the hole with weld and re-drill.

To keep the drill bit on track (drilling through weld can be, er, interesting), perhaps drill a 7/8 hole in a hunka steel plate, tack weld it on, then use that as sort of a drill guide. (You could also start with a smaller hole like 1/4" and work your way up from there; might be easier.) And/or if there's room in the mechanism, maybe you could leave the doubler in place after trimming and welding it properly, and maybe end up with a much sturdier part.

 

[The Cobbler]

The hole originally was 7/8" and accepted a bushing and bolt through it

are you able to weld a nut to the flange and then thread the bolt with the bushing in place?

 

[dante2]

I think you'll melt the brass bushing, if you're talking about welding with the bushing in place.

I'd just locate the center as best you can, then fill the hole with weld and re-drill.

To keep the drill bit on track (drilling through weld can be, er, interesting), perhaps drill a 7/8 hole in a hunka steel plate, tack weld it on, then use that as sort of a drill guide. (You could also start with a smaller hole like 1/4" and work your way up from there; might be easier.) And/or if there's room in the mechanism, maybe you could leave the doubler in place after trimming and welding it properly, and maybe end up with a much sturdier part.

Unfortunately that's it on the thickness. Looks like a fill and drill job. Just time and I have plenty of that. Thanks for the help now I need to get a 7/8" bit.

 

[dante2]

are you able to weld a nut to the flange and then thread the bolt with the bushing in place?

I don't think so. This is the bushing and the 2 brackets are stacked with the bolt thru the deck. No real tolerance for anything else since everything little thing effects the belt angle.

 

[no704]

Unfortunately that's it on the thickness. Looks like a fill and drill job. Just time and I have plenty of that. Thanks for the help now I need to get a 7/8" bit.

Just use a step drill.

 

[RoninB4]

Unfortunately that's it on the thickness. Looks like a fill and drill job. Just time and I have plenty of that. Thanks for the help now I need to get a 7/8" bit.

-Drilling a partial hole, an interrupted cut, is going to be a bit sketchy with a drill press. The excess weld/braze on the worn side will tend to push a drill over to the other side. It will either snag, catch, of go off center even if the part is clamped to the table. Do you have a milling machine or a lathe? You do what you want to but you're intent on using a drill press I'd strongly suggest using quill feed control in the order of .007 down-feed on a peck cycle. If you use a twist drill it can snag, break the drill, mangle the bracket, and/or launch the workpiece. If you're using steel for filler your cutting speed will need to be fairly slow (making it more snag prone) or a carbide cutter will be needed. This is all the more reason to do this in a mill or lathe. Better results, better control, more cutter options this way.

If you were closer I'd have you bring it over and do it while you watched/learned. If you're going to use a brass (or other material....) bushing then now would be a good time to plan of employing a replaceable bushing into the design for next time. Wear properties for brass aren't very good for some things. Post your intentions.

 

[Beerhippie]

I'll bet @KwikFab could reproduce that. Maybe he'll pitch in.

 

[jbltwin1]

Weld up the egged out part and get the router bits out and re-round it. Or weld the hole up and re-drill. I've done both. Actually, just did something similar on JD pivot bracket. It had a 1/2" steel boss on a 3/16" or so bracket with a .502 hole for a shouldered bolt. . I elected to just cut the boss off, center bore a 1/2" hole in a piece of 1" stock. Cut it roughly to length and then turn it square and length on the lathe. Stick reamed it an extra .002 for slip clearance and them MIG'd it on bracket. Easy peasy.

 

[KwikFab]

I'll bet @KwikFab could reproduce that. Maybe he'll pitch in.

I'll check the thread tonight or tomorrow!

Literally getting ready to head out of state (NV).

 

[Caneil]

Could use a piece of graphite rod that's the diameter of the hole you want. Put it where you want the hole, weld right up against it. Even if one has to break it up to get it out, the diameter and location are still right.

 

[rsanter]

You use copper as a resist to mig welding, not brass

just lay some weld in the hole where it got oblonged and then die drinker to make round again

 

[rlitman]

...now I need to get a 7/8" bit.

I strongly suggest not doing that. The step drill is your friend here. Especially when it comes to situations like this, step drills with their long circular wedding cake stair steps drag on the edges of the hole, keeping the bit well centered and the hole round. A regular twist drill is going to bite into the edge and that's going to **** when you find out that the welded edge goes from hard to soft all over the place. You'll end up with a real ugly hole, if it doesn't break the drill bit or throw your part.

Or, if you don't mind a perfect fit, welding just the worn side and then die grinding back to round is an option.