Drill Press Casting Crack - Repair or No?

[RaisedByWolves]

I have a similar drill press from MSC so had to go look at it. On mine, the threaded hole is
about 1/4 inch higher than on yours. Gravity holds the head on and one would think that the
Allen screw is there to keep the head from rotating. I think it would be prudent to make a
threaded hole on the opposite side of the press a little higher up and then remove the screw
that has the crack so there is no pressure on the casting there. If there isn't a crack forming
above the hole, it's not a big concern. Then fill the hole with JB Weld and dab on a little paint
on that spot so you can't see it.

Also, I removed the Allen screw to see if it pins the head in a certain position going into a hole
in the pipe or something, but the screw just presses against the pipe to hold the head in place..

The problem with putting the screws on the other side is it may/might/could tilt the head bit. If you look you can see two more "Fixing" screws above that one.

Whether this will ever matter is the questions that keep me up at night.

 

[Nuke_It_Newport]

Thats a poor design and liable to fail again after repair. Honestly it looks like someone reefed too hard on the screw causing that.

I would take off the head and redrill/tap that hole an inch further up.

I think this is what I'm going to do.

Either that, or epoxy the heck out of it with J-B metal. That is probably the world's most common drill press design, from Craftsman to Harbor Freight and every store brand in between. Not much cause to remove or pivot the head, and if you do, the foot is staked with the same type of screws. It may have been overtightened, or it may have fallen over at some point. Either way, a good epoxy joint will be stronger with less stress on the casting.

I have noticed this same casting on many other brands. I replaced the quill shaft with a Jet part as one of the handles had boogered threads. Are you saying to remove the set screw, slather epoxy in the hole, then retighten the screw?

I was going to say it was good that the crack is below the hole and not above as the hole should limit the tendency of the crack to migrate. But... I think I can see a small hairline of the crack above the hole as well which isn't comforting. Looks like there's room on the bottom of that casting to slip a collar -- thinking of something like a really beefy hose clamp -- but I don't know if that would really do anything or not.

View attachment 464371

Good eye! There is a small crack above the hole as well.

A bulletproof fix would be to drill the existing hole out to a clearance diameter. Turn a steel ring with a ID that will fit over the existing casting hub.
Ring ID may want some taper to accommodate draft present on the hub OD. Epoxy ring in place. I would clean off the paint before bonding, but with the sand cast texture, that would probably not be necessary.

I've considered something like this, but I don't have a lathe (yet!).

I have a similar drill press from MSC so had to go look at it. On mine, the threaded hole is
about 1/4 inch higher than on yours. Gravity holds the head on and one would think that the
Allen screw is there to keep the head from rotating. I think it would be prudent to make a
threaded hole on the opposite side of the press a little higher up and then remove the screw
that has the crack so there is no pressure on the casting there. If there isn't a crack forming
above the hole, it's not a big concern. Then fill the hole with JB Weld and dab on a little paint
on that spot so you can't see it.

Also, I removed the Allen screw to see if it pins the head in a certain position going into a hole
in the pipe or something, but the screw just presses against the pipe to hold the head in place..

Mine has a roll pin as well as the 2 set screws. I'm thinking the set screws are there to take up the slop, and the roll pin keeps the head from rotating. It is cracking above the hole as well, but it's very small.

I wouldn't spend any time on it- it's typical low grade cast iron

I probably should leave it alone! I know it's not a high end piece of equipment, so I don't want to put a ton of cash in it. Maybe I'm OCD. It bothers me to not repair it. I tend to overthink things, and overkill everything I build.

The problem with putting the screws on the other side is it may/might/could tilt the head bit. If you look you can see two more "Fixing" screws above that one.

Whether this will ever matter is the questions that keep me up at night.

I considered that as well. I lose too much sleep worrying about things that probably don't matter.
Thank you all! You guys have a great forum here.

 

[Lo-Fi]

Best way to stop a crack is with a hole! So drill one a little further up to stop the crack propagating. File or machine a flat and fit a little plate over the bottom part, fix with epoxy and small machine screws.

 

[pontiac428]

Are you saying to remove the set screw, slather epoxy in the hole, then retighten the screw?

The single, strongest epoxy joint that can be made is a slip-fit pipe joint, just like that. I mean slather the inside with peanut butter and the other side with jelly (okay, epoxy both sides and don't use food) and join the two pieces forever. If someone shoved the machine out of the back of a moving truck, the casting will shatter around the joint, but the joint will hold.

I'm not a glue-hack by any means, but considering what you are working with, how much time it deserves, and what it needs to do, this would be my first choice. I'm well equipped to weld cast iron using a half dozen methods, but this just isn't one of those jobs.

 

[Nuke_It_Newport]

The single, strongest epoxy joint that can be made is a slip-fit pipe joint, just like that. I mean slather the inside with peanut butter and the other side with jelly (okay, epoxy both sides and don't use food) and join the two pieces forever. If someone shoved the machine out of the back of a moving truck, the casting will shatter around the joint, but the joint will hold.

I'm not a glue-hack by any means, but considering what you are working with, how much time it deserves, and what it needs to do, this would be my first choice. I'm well equipped to weld cast iron using a half dozen methods, but this just isn't one of those jobs.

I understand what you mean now. Thanks. I hadn't considered that method. I guess if the casting ever failed in a catastrophic manner, it wouldn't be worth salvaging the column. At the end of the day, it's a $200 machine, not a $6000 machine. I've found JB Weld to be surprisingly strong in certain applications, if the surfaces are prepped properly.

 

[extropic]

I've considered something like this, but I don't have a lathe (yet!).

Ask someone to make the ring for you.

CAN YOU MAKE SOMETHING FOR ME?

You need a part or some tooling. You can't or don't want to make it. Maybe someone here can do it for you.

www.hobby-machinist.com

 

[Nuke_It_Newport]

Ask someone to make the ring for you.

CAN YOU MAKE SOMETHING FOR ME?

You need a part or some tooling. You can't or don't want to make it. Maybe someone here can do it for you.

www.hobby-machinist.com

Thanks! I may consider that.

 

[Nuke_It_Newport]

An update, for anyone that's interested. I separated the head from the column. To my dismay, the casting design was not of a design that I could drill and tap a hole above the existing hole. The casting only contacts the column in two locations (where the set screws are located, see attached pic). This left me with the options to leave it alone, epoxy the head to the column, or have a ring machined to encircle the cracked casting. Being that this is not a high dollar drill press, I opted to JB weld the head to the column as pontiac428 suggested. I "scotch brited" and cleaned all mating surfaces with carb cleaner, slathered with JB Weld, reassembled, epoxied and reinserted both set screws, then cleaned everything up, removing all excess epoxy. It should be hella strong, looks good, and only cost $22 for the large tubes of epoxy. While everything was disassembled, I cleaned and greased all the internals, blew out the motor and put a couple of drops of oil in the lube points. I got the pulleys aligned pretty well, which helped with vibration somewhat. I was able to get my runout at the chuck down to .0015. For what it is, I'm satisfied! Thanks again to everyone for the help.