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laddy
06-10-2010, 03:19 PM
Hey,
I know this is opening up a can of Worms. I am styrictly a hobby "machinist" not working for those super tolerances (couldn't get them if I tried). I have a Sheldon/Vernon vertical mill that I bought from a neighbor. It has a few defects in the table none of which has affected me. One is like a giant apostroph 1/16th deep 3/4 by 1/2 inch. I came across an ad for "Alvin Lab Metal" That is machinable, sandable, drillable, tapable, fileable etc.
What if this defect was filled with that and carefully "flattened to table??? At least it would look better and not catch as many chips. It adheres to wood, plastic, cast, all metals....what do you think?? I am not going to remove table have it welded, scraped etc. Is this a totally dumb idea???? Thanks to all that give advice. Fred

scmw
06-10-2010, 03:31 PM
If you're going to do lab metal, you might as well do bondo or an epoxy filler and just sand it smooth. I don't believe that lab metal is that much stronger than an epoxy. My experience with it has not been that good.

Hope this helps,
Terry

gnm109
06-10-2010, 04:12 PM
Hey,
I know this is opening up a can of Worms. I am styrictly a hobby "machinist" not working for those super tolerances (couldn't get them if I tried). I have a Sheldon/Vernon vertical mill that I bought from a neighbor. It has a few defects in the table none of which has affected me. One is like a giant apostroph 1/16th deep 3/4 by 1/2 inch. I came across an ad for "Alvin Lab Metal" That is machinable, sandable, drillable, tapable, fileable etc.
What if this defect was filled with that and carefully "flattened to table??? At least it would look better and not catch as many chips. It adheres to wood, plastic, cast, all metals....what do you think?? I am not going to remove table have it welded, scraped etc. Is this a totally dumb idea???? Thanks to all that give advice. Fred


JB Weld fast-setting variety does a wonderful job on table divots. Once it sets and gets some way oil on it, you won't even notice it anymore.

saltmine
06-10-2010, 04:26 PM
Why play around with plastic fillers?

I'd drill it out with an end mill, ream it to a real close fit, and make a plug on my lathe out of mild steel bar stock round. A couple drops of Locktite, and a hammer to "set it" with an interference fit, then grind off the excess. If needed scrape it level, and you'll have a permanent repair.


The biggest problem I had when starting out was; I can't fix that....WHY not? it's a piece of grey iron or steel. Don't dance around it, dive in!

Fasttrack
06-10-2010, 05:31 PM
I'd steer clear of Bondo. Polyester fillers don't tend to adhere very well, in my experience. JB Weld seems to be a common technique as well as that mentioned by saltmine.

Rex
06-10-2010, 05:41 PM
Similar thread on another forum this week.
Several report good results with Liquid Steel and similar products.
I'd sure do it. You certainly won't hurt anything.

vpt
06-10-2010, 05:42 PM
Why play around with plastic fillers?

I'd drill it out with an end mill, ream it to a real close fit, and make a plug on my lathe out of mild steel bar stock round. A couple drops of Locktite, and a hammer to "set it" with an interference fit, then grind off the excess. If needed scrape it level, and you'll have a permanent repair.


The biggest problem I had when starting out was; I can't fix that....WHY not? it's a piece of grey iron or steel. Don't dance around it, dive in!




^ Thats what I'd do.

gnm109
06-10-2010, 07:29 PM
I'd steer clear of Bondo. Polyester fillers don't tend to adhere very well, in my experience. JB Weld seems to be a common technique as well as that mentioned by saltmine.


Gee, I mentioned using JB Weld and I don't even get so much as a wham, bam, thank you man. It's OK, I'm used to being ignored. Been married for a long time.........:)

I had a couple of small end mill notches in my big Webb when I got it and I used JB Weld. You can't even see them after a year. That stuff is very, very hard.

MotorradMike
06-10-2010, 07:37 PM
Since nobody has mentioned it, I'd suggest a bit of J-B Weld.
Once it gets some oil on it, you won't even notice the repair.

gnm109
06-10-2010, 07:39 PM
Since nobody has mentioned it, I'd suggest a bit of J-B Weld.
Once it gets some oil on it, you won't even notice the repair.

Right....."nobody" mentioned it. LOL. :)

doctor demo
06-10-2010, 08:10 PM
Why don't You try JB Weld, I can't believe it hasn't been brought up yet.

Steve

Tobias-B
06-10-2010, 09:22 PM
Well, since no- one ELSE has mentioned JB Weld, why not a metal- bearing epoxy??!! :p

Seriously, I'd look for a 2- part epoxy that has good adhesion to metal, maybe
rough up the bottom (or undercut the sides) of the gouge,
and then fill it. Use an aluminum file to take the high spots down,
and you're good to go.

Me, I just avoid the few 'PO divots' in my cheap and cheerful Taiwanese mill,
and am a happy race car fabricator...

heh

t

MichaelP
06-10-2010, 09:27 PM
How about something as simple and invisible as JB Weld? I'm a bit surprised nobody mentioned it yet.

P.S. If the holes don't interfere with your work, you really don't need to do anything at all.

P.P.S. Alternatively, you can try JB Weld. Usually, people forget mentioning it.

saltmine
06-10-2010, 09:58 PM
Since I used to be a welder, and repaired cracked engine blocks and cylinder heads...I figured an interference fit plug would be appropriate.
Welding on a mill table would introduce stress and warpage....

We used to repair cracked blocks between cylinders on Ford "Y" block engines by drilling a series of holes along the crack and pounding in "iron-tight" plugs, with a hammer. You grind them flush, and put the head back on...I've never seen one fail.

sjlarkin
06-10-2010, 10:11 PM
This maybe of interest . http://moglice.com/

Fasttrack
06-10-2010, 10:54 PM
Sorry gnm109 - I did read your post but I was commenting on the earlier suggestion to use either bondo or two part epoxy. It just seems like this topic comes up a lot and the generally accepted solution is JB Weld. Didn't mean to steal your thunder ;)

rolland
06-11-2010, 12:07 AM
JB weld sounds like a good idea

gnm109
06-11-2010, 12:11 AM
Sorry gnm109 - I did read your post but I was commenting on the earlier suggestion to use either bondo or two part epoxy. It just seems like this topic comes up a lot and the generally accepted solution is JB Weld. Didn't mean to steal your thunder ;)

I was just kidding you. LOL. I use J.B. Weld for lots of things nowadays. It sure beats welding cast iron. :)

Boot
06-11-2010, 10:51 AM
Right....."nobody" mentioned it. LOL. :)
When I was working in a machine shop when we made a boo boo on a cast iron part we patched it with a compound made by Devcon. We called it by that name and we filled in many holes with it. It was same color and it was made for patching cast iron. That was 10yrs ago so I don't know what that company has out now. It sort of looked like JBweld compound a gray color.
Boot

lynnl
06-11-2010, 10:53 AM
gnm109, do you sometimes feel like maybe you're a long-lost brother of Rodney Dangerfield? :)

I know that feeling ...it's disheartening isn't it? :)

gnm109
06-11-2010, 11:01 AM
gnm109, do you sometimes feel like maybe you're a long-lost brother of Rodney Dangerfield? :)

I know that feeling ...it's disheartening isn't it? :)


Sure do. I get no respect! But If you want to really know what I'm like, rent a copy of "Natural Born Killers" and watch Rodney's performance.....LOL.

:)

sidneyt
06-11-2010, 03:21 PM
Let's hear it for gnm109 and JB Weld. Hip, hip, hurray!

I think JB Weld is a great solution.

laddy
06-11-2010, 05:20 PM
Thanks to all for the help!! I would like to do the endmill steel repai but fear I will screw things up more than they already are. I think I will go with the JB weld and keep the steel repair for later. I appreciate the great help. Fred

Peter.
06-11-2010, 05:30 PM
Welding on a mill table would introduce stress and warpage....


Not if JB did it :D