RF-30 mill drill

[stevec]

In preparation for an upcoming downsizing I am considering refurbishing my RF-30 mill drill.

Years ago the head casting cracked due to the head to column locking mechanism. It is a "squeeze the head on the column" type.
Not the more recent type that utilizes 2 clamping devices in tandem without "squeezing " the casting.

I had it welded by a professional (?) weldor as I have never welded cast iron.
Apparently the "professional weldor never had either because it cracked anew shortly after re-assembly.

I'd love to buy a new casting, of the more recent clamping method but "Busy Bee" the Canadian equivalent (not!) of Grizzly Tools
says the casting is not available.

If anyone knows of a supplier that might avail me of said casting I'd really love to know who.

My RF-30 corresponds to the Grizzly Model: G0705

Any help would be appreciated.

Thanks,

Steve

[ieezitin]

Steve,

Silicone bronze or aluminum bronze Tig will work and turn out to be a great repair.

completely grind out the crack and profile into a deep V larger the better, do this with a steel rotary burr bit and not a disc grinder 

Cut a slug on the lathe the same size diameter of the mill column, install the head on the slug and firmly apply pull straps to squeeze the head on the slug-pin. thoroughly  clean  the ground out V to be welded again and now put this in an oven and heat to about 400-500.

bring it out on the table and keep it wrapped in welding blankets tig it up it up, if you cant do it take it back to the welder and tell him how to do it.

Its not hard to weld CI.

Its a shame because if you don't repair this one if you find a second hand mill you're going to pay through the nose for it, i would not think you could buy a new old stock one.

Hope this helps

Anthony.

[Sunset Machine]

I have one too, it's handy but not very well built or designed. I think replacing it would be better than wearing this dead bird around your neck for evermore.

[stevec]

Thanks Anthony, I don't have a tig welder and I don't think the casting will fit in the oven (even if I could get the wife outa the house long enough).

Also, what material would the "slug" have to be so as not to become welded to the whole mess?

I wouldn't consider buying another mill drill even if the price was good  because then I'd have another useless cross slide table on my hands.

Sunset, I think you're right.

Steve

[Sunset Machine]

Sorry not to be of much help, but that thing is busted. If I recall, the head is cracked at the bottom near a clamp? There are three poorly placed clamp bolts on mine. I usually just use two (cuz I can't get a wrench on the other). Any chance of drilling a new hole for a new clamp?

The prices they ask for mill/drills today are more than a used turret mill goes for around here. I saw two last summer in the loading area of a shop, waiting for the scrap man. Any of that going on in your neighborhood? They're usually pretty cautious about selling their old machines to competitors- hobby guys have to knock on their doors.

[dallen]

Steve lives in the land of you can't get anything

[stevec]

(08-31-2015, 09:19 AM)dallen Wrote: Steve lives in the land of you can't get anything

Almost "right on" dallen!  Actually you CAN get, frustrated, ripped off, overcharged, overtaxed and tired here. And those are just some of the free things.

Sunset, I'll prolly just keep my TREE mill, when and if we downsize. I was just thinking of ridding myself of the mill stone (uh, I mean mill drill) around my neck. Sorta in the classification of "ripped off" only I'd get to do the ripping.  

Seriously, I'm  gonna do something with it because, over time, I've fitted it with "X" power feed, power "up & down" for the column,
DC variable speed spindle control, as well as a DRO for the spindle .

Steve

[Sunset Machine]

I get it - this is your baby. Kinda brings a tear to my eye. Somewhere I saw one of these with the head laying sideways on the table for driving a boring bar. The bar itself was attached to a loader bucket in the usual manner but coupled through u-joints and a shaft to the dead mill/drill in the back of a truck.

[stevec]

(08-31-2015, 12:52 PM)Sunset Machine Wrote: I get it - this is your baby. Kinda brings a tear to my eye. Somewhere I saw one of these with the head laying sideways on the table for driving a boring bar.  The bar itself was attached to a loader bucket in the usual manner but coupled through u-joints and a shaft to the dead mill/drill in the back of a truck.

Sorry Sunset, I don't understand.

Steve

[Roadracer_Al]

I had a similar mill/drill. I also found the head pinch to be completely inadequate. The first problem was that the pinch bolts were made from really terrible steel and literally wore out. $55 over at Fastenal for suitable replacements -- grade 8 SAE fine thread and matching nuts -- and that particular problem went away.

Then the head casting cracked. The strange thing is that the head still locked up on the column perfectly well.

I looked it over and decided that if I were serious about keeping the thing (I wasn't locked into continued ownership of a smaller machine), I would consider fabricating a replacement head out of steel as a welded construction, with a few upgrades, mostly a split-collet head fixing solution, and maybe an extra inch or two of throat depth.

Before you go shaking your head, mumbling "that Roadracer, he's crazy".... think about it: it's just a box with a couple of cylinders inside it. There are three precision holes in the box: the quill, the column, and the downfeed. Heck, the downfeed isn't even all that high precision. Then after that, there are a bunch of tapped holes.

I'd build it entirely out of mild steel plate, maybe 3/8". The quill and column holes would start as tubing, and should be rough bored .15" undersize to allow for possible weld distortion, then finished on a knee mill after welding. The two holes which matter most (quill & column) can be bored in one setup.

What would be super cool would be to design it in CAD so it can be laser or waterjet cut with interlocking tabs and slots to ensure correct alignment when assembled. I'm sure if you reached out to some US-based members that they would be happy to help you get this service -- I have a very good waterjet vendor, and I can help, but I'm in CA... shipping would be a killer. Perhaps someone on the East Coast can git'r'dun.