Drill Table Repair ( or using GQ's scraping as camouflage )

[Anorak Bob]

The table Gregory brought me last Sunday had 3 drill holes in the work surface. One 1/4" , one 2.5mm and a mess roughly in the centre where a number of mistakes had finally created a through hole. A neat through hole is very handy, specially with the over centre clamp I have on the drill.

I bored out the hole to remove all evidence of damage. I then discovered that Waldown did not position the cast boss directly on the spindle centreline so I have an offset hole. It is big enough to accommodate a 3/4" drill without contact.

I thought that I would have a go at plugging the two remaining holes with some cast iron. I turned up a couple of 0.001" oversize plugs from a 4E offcut. I had redrilled the holes in the table to ensure that the hole edges were sharp and after turning a 15 degree bevel on the plugs, drove them into the table. I had wiped a thin coating of Loctite around the walls of the holes prior to insertion. I peened the edges of the plugs then scraped them flush.

An easy enough job.

The 4E is slightly lighter in colour than Waldown's cast iron. I reckon I can live with that.

BT

[Michael G]

Nice one Bob

Michael

[Steamwhisperer]

I am suitably impressed Bob. Fantastic job

Phil

[Anorak Bob]

Nice one Bob

Michael

Thanks Michael,

I must admit to being a bit tentative when I arrived at the point of peening. I didn't know if the peened edge would fracture rather than deform. Deform it did, thankfully.

Bob.

[Ueee]

Nice job Bob:2tsup:

I would think if you took a piece of cheap Chinese cast it would just break when peening, but it amazes me sometimes how malleable cast iron can be. A bit of work on the drill and you'll never see the colour difference.

[Stustoys]

Hi BT,
I thought I replied to this earlier but it seems to have gone astray.

Is this the plug of the first repair?
A little flight rust and you'd never know it was there ;)
Great work as always Bob.


Stuart

[Bryan]

Another vote for 'well done Bob'. :brava

[Log]

Good repair there:2tsup:, unfortunately now that Stustoys has enlarged that pic you'll have to go back and repair, that once tiny hole to the left, which is now a giant:)( :D:doh:

Cheers.

[Anorak Bob]

Hi BT,
I thought I replied to this earlier but it seems to have gone astray.

Is this the plug of the first repair?
A little flight rust and you'd never know it was there ;)
Great work as always Bob.


Stuart

I think so Stu. There is a slightly different coloured concentric edge between 4 and 6 o'clock inboard of your red circle.

I posted these photos to show how easy it is to repair a few nasty drill holes. Sadly, a lot of drill press tables are the victims of careless abuse and while the "new" table on my drill looks like it has served as an anvil, it only had minimal drill damage.GQ's Biaxed surface made the concealment of the repairs simple.

The table on my other Waldown has been fly cut. It would be difficult to plug and conceal a hole in it. On the other hand, both of my mills have smooth(ish) shiny tables as do a lot of other mills. Executing the repair of an errant hole would not be too difficult as long as the finishing was done with a delicate hand. Colour matching the cast iron would tend to be a luck of the draw thing.

Still, to me, an honest visible repair is better than no repair.

BT

[Anorak Bob]

Good repair there:2tsup:, unfortunately now that Stustoys has enlarged that pic you'll have to go back and repair, that once tiny hole to the left, which is now a giant:)( :D:doh:

Cheers.

Been and gone Log.

The 2.8mm plug for that hole is shown in the photo with the ruler. I was going to leave it because it was shallow, maybe no more than a millimetre. Then I thought, one of you blokes will have a go at me for being slack.

BT

[Stustoys]

Hi BT,
I doubt I would have found it if I didnt have the small hole to go off. I only had to enlarge it 400% and even then the first circle I had drawn was in spot at about at around 1 o'clock from the small hole but I figured it was to small.
Next guy that walks into your shop that hasnt seen the pictures, ask him if he can see anything.

an honest "barely" visible repair (still pictures can be tricky things)

Stuart

[Steamwhisperer]

Been and gone Log.

The 2.8mm plug for that hole is shown in the photo with the ruler. I was going to leave it because it was shallow, maybe no more than a millimetre. Then I thought, one of you blokes will have a go at me for being slack.

BT

Now, if only I could stop you using loctite.....

Phil

[Bryan]

Yeah, we're always saying that. That Anorak, he's so slack. Never does anything properly. :roll:

[Steamwhisperer]

Yeah, we're always saying that. That Anorak, he's so slack. Never does anything properly. :roll:

How true Bryan. Not a word you would associate with Bob....ever.

[Anorak Bob]

Now, if only I could stop you using loctite.....

Phil

Ne'er a bottle of the stuff would be seen at Sovereign Hill.

It would have been smeared off the mating surfaces in the table when I belted the pins in. I know you are winding me up but the stuff does come in handy. Held a few of my motorbikes together when I was a young bloke.:U

BT

[Steamwhisperer]

So long as you don't tell anyone Bob, I may have used some in the past. Never at the 'hill' though lol

Phil

[RayG]

Very impressive BT, I love the way you raise the bar a little each time... I was thinking of a similar repair using some kind of epoxy mix.... not now.. :D

Regards
Ray
(taking a break from working late.)

[Steamwhisperer]

Hi Bob,
here is how they did it from new to repair any blowholes in the casting. White metal. Given a choice I would do exactly what you did. Heaps more skill involved and a far better finish...and satisfaction.
This drill table is from the post drill at the 'hill'.

Phil

[Anorak Bob]

I had been wondering where you were Ray. Glad you're back.

Phil, my little Hercus mill has some infill metal on the Y dovetail. Could be white metal. I'll post a snapshot.

BT

[eskimo]

geeeeez..........you just took away all that patina and history......



of abuse:2tsup:

[Kraehe]

A very impressive repair.

I will need to do something similar with my drill press table. I had considered cast iron interference fit plugs like your repair, but was concerned about inducing stresses in the table. Is this a potential problem? How does one calculate the stresses and possible effects? (Are there any physics gurus here?).

May I ask also; why did you peen the plug? Doesn't this put more stress on the base structure?

Thank you. Regards, K.

[Anorak Bob]

A very impressive repair.

I will need to do something similar with my drill press table. I had considered cast iron interference fit plugs like your repair, but was concerned about inducing stresses in the table. Is this a potential problem? How does one calculate the stresses and possible effects? (Are there any physics gurus here?).

May I ask also; why did you peen the plug? Doesn't this put more stress on the base structure?

Thank you. Regards, K.

Hello Kraehe,

The plugs were only 0.001" oversize and they were small in diameter. The underside of the table is ribbed and the plug locations were close to one of the ribs. I don't know about the stresses imparted in the table by my plug insertion but close inspection of the table surface suggests that some clown used it as an anvil in its former life. Greg probably scraped away any surface deflection caused by that abuse.

The peening was simply done to ensure a no gap fit at the visible end of the plug. I was gentle with the hammer.:U

BT