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Evan
04-26-2004, 11:30 PM
Now that the weather has warmed and the garage shop is again usable I have started this past weekend on restoring the 2HP Strand gearhead drill press that I got for Christmas. I took the 16" cast iron table off and hauled it down to the job shop in town to have it faced off. They did a nice job, cleaned it up very well. But, there are a few small partial holes where someone drilled into the table and I would like to fill them with something that looks as much like the cast iron as possible. Suggestions?

http://vts.bc.ca/img/table1.jpg

BillH
04-26-2004, 11:37 PM
They really bother you that much?

Maker
04-26-2004, 11:43 PM
Evan, you can get close with JB weld mixed with cast iron filings, but it will look iffy at best. How about drilling the holes through and using iron bar machined to dia as plugs? That will look pretty good (I think) and won't leave a soft spot on the table.

Good Luck

Alex

Evan
04-26-2004, 11:51 PM
Bill,

Yes, they bother me.

Alex, I don't think I could bring myself to drill through the table. I also don't think such small soft spots present any problem. This is only about appearance.

wierdscience
04-27-2004, 12:15 AM
I have seen a few table and way "hickkey's"filled with lead and or tin solder,it stays put.I have myself glued on a overlay table out of thin(12ga.)sheet,just match the slots close as possible and attach with a thin coat of epoxy.I did that to a belt sander platten that was screwed up royal,I use 1/8" polished stainless and attached it with an epoxy called plumber's seal,its been five years with lots of heat and vibration and its still going strong.

Mike W
04-27-2004, 12:52 AM
www.caswellplating.com (http://www.caswellplating.com) has a pit filler called Pitstop. It is a 2 part epoxy resin loaded with pure silver. It is used to repair flaws and then the item is plated. I am just getting into the plating hobby. How about a nickel plated drill press table?

Maker
04-27-2004, 01:21 AM
OK, how about treating the holes like a wood worker would. Instead of drilling through the table, turn some CI plugs and tap in like a furniture maker filling screw holes with wood plugs.


Alex

Evan
04-27-2004, 01:23 AM
I like the lead idea Wierd. Pretty close to the same color and easy to do. Can also be reversed easily if it doesn't turn out.

Steve Klopp
04-27-2004, 01:36 AM
Hello Evan
On my old Dewalt Drill Press i Drilled through and put cast iron plugs in. I then Srapped the table flat, you cannot see them at all unless you look at the bottom.
Steve

suprdvn
04-27-2004, 09:51 AM
I wish I could get a picture of the vice on a bridgeport in our maintainance department. There is nothing left of the surface in front of the solid jaw. Practically drilled in two! http://bbs.homeshopmachinist.net//rolleyes.gif

Super Dave

pat bearss
04-27-2004, 10:39 AM
Evan, I had a similar problem with an antique drill press. I went to the local welding supply and picked up a castaloy rod for welding cast iron. Some friends have even welded and repaired old flathead Ford engine blocks.
Pat

DR
04-27-2004, 10:47 AM
I have a large CNC mill that has some "repair" spots on the table. These were done at the factory in what appear to be voids in the original casting.

The table is cast iron, the repairs are a more silver colored metal. I wonder what process and material was used. The only clue that anything was done is the slight color difference visible on close examination.

Paul Gauthier
04-27-2004, 11:25 AM
I would not use lead, not because it is toxic, but because it will loosen up in time. Drill and tap and install cast iron plugs using a two part epoxy on the threads, or find some Devcon Steel filler.

------------------
Paul G.

Paul Alciatore
04-27-2004, 11:29 AM
Evan,

I like the CI plug idea and don't see any reason why you would have to drill all the way through the tabled to install them. Just get a clean sided hole and a short plug to fit. I bet you could make the plugs a bit oversized and use a shrink fit for a permanent bond.

Paul A.

Evan
04-27-2004, 11:44 AM
The cast iron plug idea sounds good except for the two holes on the edge of the slot. I would not think that it would be wise to try a press or shrink fit on those holes. I'd be afraid of cracking the iron. I think I will try some of the Devcon on those holes. Thanks for the ideas guys.

quasi
04-27-2004, 01:22 PM
Evan, why not stamp OIL beside each hole? just kidding. If it were mine I think I would make a subtable for it, as in bolt on a table on top of the original table, maybe one with t-slots. Cast iron or steel plate from the junk yard or maybe some 7075 t6 plate? I am sure there is lots of that in the Caribou!

Gator
04-27-2004, 01:48 PM
Evan,
I would do as Paul Alciatore said and with a bit of Devcon, but before you had it faced off.

Larry

Evan
04-27-2004, 02:03 PM
Yeah, didn't think of that.

Paul Alciatore
04-27-2004, 02:05 PM
<font face="Verdana, Arial" size="2">Originally posted by quasi:
Evan, why not stamp OIL beside each hole? ...</font>

Hey, I love it. You might put a grease fitting on one or two for variety.

Paul A.

Forrest Addy
04-27-2004, 02:10 PM
Try these guys:

http://www.irontite.com/crack.htm


Their website is miserable but briefly they sell taper threaded cast iron plugs of a dozen different sizes and taps to prepare the holes for the plugs. When installed in a casting defect with a thread locking agent they are gas tight. When the repair is complete you flush the heads and machine the surface as requred.

You can find them at automotive and trucking supply centers serving the fleet industry.

Be careful when you install the plug you don't wrench them beyond barely metal to metal.

I suggest after you repair the holes upu hand scrape the surface to improve flatness (I bet it's convex with humps at the edge where they grabbed the flange in the four jaw) with the object of enhanceing the finish.

John Stevenson
04-27-2004, 02:12 PM
<font face="Verdana, Arial" size="2">Originally posted by Evan:
Bill,

Yes, they bother me.

This is only about appearance.</font>

Evan,
I use my drill press for drilling.
I have a plate for eating my dinner off http://bbs.homeshopmachinist.net//biggrin.gif

John S.

Evan
04-27-2004, 02:34 PM
Forrest,

I had thought about trying my hand at scraping. This looks like a good first project, I can't screw it up too much. As for flatness they didn't have to grip it at the circumference. The table mounts via a 2.5" machined center stub underneath that is all one part of the casting. All they had to do was chuck up on the stub so there is no distortion of the table. That also insures that the table top is perpendicular to the rotational axis.

spkrman15
04-27-2004, 05:37 PM
Evan,

Why not get it welded. There are some really good welders out there that will understand what you are looking and will do their best. It might take some leg work but a little word of mouth and you would be surprised. Ask the shop you brought it to.

Just a suggestions. Epoxys are good but they still aren't the real thing

Rob http://bbs.homeshopmachinist.net//smile.gif

JCHannum
04-27-2004, 06:51 PM
If it were mine, I would leave it alone. That way, if I missed and put a spot on the table, I could always blame the other guy.
If you must hide the holes, use JB Weld. It is as good as Devcon or the other epoxies for this purpose and much cheaper. It blends well with most cast iron and sets up quite hard.

John Stevenson
04-27-2004, 08:09 PM
The trouble with Cast Iron welding is the filler rod isn't cast iron but a nickel based alloy.
The problem with this is it's as hard as witch's tits to remachine and it's a totally different colour, being a lot brighter and shinier.

I have got away with a couple of very badly marked drill tables by replacing these with old lathe faceplates.

John S.

CCWKen
04-27-2004, 10:10 PM
Plug the holes with dowel rod, fill the slot boo-boos with epoxy and use it for a casting blank.

Sell the old table to someone that doesn't have one at all.

Evan
04-28-2004, 01:05 AM
I believe I am beginning to detect a slight note of facetiousness here http://bbs.homeshopmachinist.net//smile.gif I'm gonna try the JB Weld or Devcon liquid steel. Since I don't plan to eat off it and I do actually plan to use it that should be good enough. I'll post a picture when it is done. Don't hold breath though, I have a lot of other things to do this time of year. It's been fun to see all the various suggestions and they have been helpful, even without a concensus.

Mike W
04-28-2004, 04:09 AM
I think it would look good copper plated. You can build up copper 1/8". Build up the bad spots and plate the whole surface. It would be one of a kind.

ibewgypsie
04-28-2004, 05:47 AM
I'd be happy with the flat spot holes and all. Buy a x-y table to cover them up.

My machine tools get used, they all have shavings under them. I clean when I can.

My mill does not have any holes in the table thou. It'd conflict with the black-gold metalflake-jeweled ways finish. I even printed up some custom stickers for it. The funniest is the "NO Rats" sticker since I ran the lil rodent outa the head. The sticky-pad is still clean, it must've been too exciting to be inside the mill motor fan housing when I turned it on. My dog just watched him escape out the door. HUH, he looked at me.. We had been drinking beer together.

David

pgmrdan
04-28-2004, 08:52 AM
Has anyone mentioned filling the holes with meatloaf? This thread has been going on too long for that idea to be missed. http://bbs.homeshopmachinist.net//smile.gif

NAMPeters
04-28-2004, 10:32 AM
When doing the final surface blending watch your lay. Your blend needs to match the rest of the table.

The top slot in your picture looks ragged and the slot to the left, as viewed, looks like it took a direct hit by a drill bit. How are you going to fix those?

On restorations my preference is to braze if the repair can not be completely hidden to show that a repair has been done. Just me and my bias.

------------------
Neil Peters

[This message has been edited by NAMPeters (edited 04-28-2004).]

Evan
04-28-2004, 11:15 AM
I don't know how or if I will attempt to fix the slots. I'm afraid to braze or weld the table as it might crack or at least warp. I don't think my wife would appreciate me preheating it in the kitchen oven. I do have an old electric stove in the barn that I could haul up to the garage to use as a preheater. I was thinking of doing that anyway. Correct me if I'm wrong as I haven't done a lot of welding/brazing on cast iron but I expect a preheat to around 400F should prevent any problems with cracking, yes? I'm in no hurry and only hope to have it done this year.

Come to think of it Dan, I could use the stove to make meatloaf. Hey Thrud, send me the recipe!

[This message has been edited by Evan (edited 04-28-2004).]

wierdscience
04-28-2004, 10:15 PM
Ya,thats called a local preheat,it will help with brazing,but if I were going to go to that much trouble I would break out the charcoal and weld it up right,it won't be as prone to warpage as you might think.Plus if you bring the entire think up to red heat you can weld it with mild steel rod,or even gas weld with old piston rings for filler rod.
I recently welded up a John Deere tractor shift top that was shattered in ten pieces,fitted all the parts together and bolted them to an old flywheel,heaped the whole thing in charcoal and started it burning while adding air from a shop hose and regulator,about ten minutes later it was red hot and I just welded it in with 7018 lohi,turned off the air and buried the part in fresh charcoal,came back the next day,picked it out and unbolted it ran it through the bead blaster and just for fun checked to see if the slide rods still worked,they did,customer was well pleased.

NAMPeters
04-28-2004, 11:32 PM
Sorry Evan,I can't answer your question with any authority as I currently farm out anything that is critical. I need to move beyond bandsaw blades and fluxcore welding, too ranch oriented. I have some neat post drills to work on so there is the incentive, now to find the time.

------------------
Neil Peters

Maker
04-29-2004, 12:48 AM
All the ideas about fillers remind me of a story a friend told me.
When they were little, he and his brother were playing soldier in their room with BB guns. After a while they realized that their parents would see the dents in the drywall and figure out what happened, and they would be punished, so they went looking for something to fill the pockmarks with. In the bathroom they found it---white Crest toothpaste!
It worked for a while, but when the Crest started to yellow, they were busted http://bbs.homeshopmachinist.net//biggrin.gif

Alex