# My new mill drill



## Dudemanrod (May 29, 2019)

Hey guys here is some pics of my Kung Foo 30 or Dung Poo or column mill drill. I know that this not the  Bridgeport  or other USA machines that i would love to have but 300.00 and with the limited space I have I hope to learn on this with the help of this cool site and your guys knowledge. Now I'm going to take it all the way down a clean and paint it. The motor says 1987 so it may need some parts. Thanks to Bob and Thom for there advice. Best way to derust the table?


----------



## Dudemanrod (May 29, 2019)

Hey guys here is some pics of my Kung Foo 30 or Dung Poo or column mill drill. I know that this not the  Bridgeport  or other USA machines that i would love to have but 300.00 and with the limited space I have I hope to learn on this with the help of this cool site and your guys knowledge. Now I'm going to take it all the way down a clean and paint it. The motor says 1987 so it may need some parts. Thanks to Bob and Thom for there advice. Best way to derust the table?


----------



## ThinWoodsman (May 29, 2019)

A good first stab would be paper towels soaked in evaporust. 

If you take the table off, you can put it in an electrolysis bath ($20 charger + $4 in rebar + plastic tub or bucket + alligator clips and cable) or soak the whole thing in evaporust ($25 a gallon).


----------



## markba633csi (May 29, 2019)

If the rust isn't too severe I just use some oil (olive, motor, castor, whale)  a 3M blue scrubber pad and a bit of elbow grease (wax on, wax off)
Mark


----------



## martik777 (May 29, 2019)

Those are great machines for the price. PITA to change speeds though. Nice switch!

Get a set of ER25 collets and collet chuck.

After derusting, a random orbital sander used lightly will clean that table up


----------



## Dudemanrod (May 29, 2019)

Thanks for the reply Mark i need some of those scrubbers so off to home depot and and will warm up my elbows. Good day


----------



## Dudemanrod (May 29, 2019)

Thanks for the replies i guess i will start tearing this beast down so i can maneuver the table and base around. Im super happy with this deal i got i was milling with my craftsman 10 inch drill press if you can believe  it aluminum of course and Chuck coming off and other dangerous things. So I'm going up town with this purchase. I'm hoping this will be a great learning mill and maybe go on to one more complex.


----------



## pontiac428 (May 29, 2019)

Welcome, Dudeman.  Looks like you're from my hometown.  I haven't been there in 20 years, though.  I hear it's changed...

For that type of rust, I like phosphoric acid based rust removers (naval jelly, evaporust, oxpho rust) because they kill rust dead and leave a finish that will hold oil for future protection.  Thin woodsman mentioned electrolosys, which you may want to look into.  I use 1/3 cup of arm & hammer sodic carbonate (a.k.a. laundry booster) per gallon of warm water as electrolyte and rebar as the anode across an automotive battery charger.  This is the method you use when you want rusty junk to come out looking like new parts, ready for paint and assembly.

Your mill is one of the older Taiwan-made Rong Fus.  Same as what I have.  With a little work, some adjustment, and the addition of a power feed and DRO, you'll have a capable machine.  A good vise is a must, and proper R8 tool holders should be used, but you've got the bulk already covered by having the machine in hand already.  Keep posting as you go!


----------



## jpackard56 (May 29, 2019)

Sounds like you're off to a great start ! 
I think you did well at that price for a Taiwan built unit. it will be "cheap" education and if it turns out to be in reasonable mechanical condition can turn out some pretty good stuff. Congratulations !


----------



## mikey (May 29, 2019)

First, welcome to HM!

Second, you have a good benchtop mill and you don't need to make excuses for it. The head alone weighs more than many mini-mills and it is capable of very good work.

I own an RF-31 which, as far as we can all tell, is the same as your RF-30. Yours is Taiwan-made so it is built to a higher quality than the more contemporary Chinese clones. Mine was in far better shape than yours but I took it completely apart anyway and de-rusted it and painted most of it. The parts breakdown is sufficient to allow for a complete tear down and reassembly.

I used electrolysis to de-rust everything - the table, base and anything else that had any rust on it other than the column and head. The column cleans up nicely with some WD-40 and gray Scotchbrite (synthetic OOO steel wool equivalent). If you need to clean up the finish on the table, take a sheet of gray Scotchbrite and use a piece of plywood to move it around manually. Use WD-40 and it will shine up the table without taking any metal off. If there are dings or high spots, use a medium to fine India stone to knock them down. 

For my mill, changing the bearings in the quill and drive sleeve made a big difference in run out. I now have less than 0.0001" TIR at the spindle, which is better than most mills out there. Your quill is a full 3" in diameter and runs in a pretty accurate hole in the head. Once locked down for work, it is quite a capable mill. 

Looks like it just needs some TLC. Ask questions and the guys will help you get it up and running.


----------



## Bob Korves (May 29, 2019)

"Rong Fu"


----------



## Dudemanrod (May 29, 2019)

Thanks Mikey im feeling better and more excited about this mill. Im planning to go through it all the way. Electrolosis seems like the way to go on the table. One step at a time


----------



## mikey (May 29, 2019)

Dudemanrod said:


> Thanks Mikey im feeling better and more excited about this mill. Im planning to go through it all the way. Electrolosis seems like the way to go on the table. One step at a time



Electrolysis will remove most of the paint along with the rust, which is good. Mask it off and paint inside the T-slots with a good oil-resistant paint and you won't likely need to do it ever again. 

I wrote up the bearing changes, they're someplace in the Rong Fu section.

You have a good machine. It is worthy of your time to bring it back to life.


----------



## RYAN S (May 30, 2019)

Very nice score!!


----------



## hman (May 30, 2019)

I have the Grizzly G1007 (also Taiwan made) equivalent to your mill.  Slightly longer table, and it came with a non-functioning table power feed.  Paid $700 for it in 2013.  I'd say you got a nice bargain.  +1 on either Evaporust or electrolysis to clean up large areas of rust.  And though I like the humor of your Dung Poo monicker, I'm generally pretty happy with the mill.  Welcome to the forum!  And if you get to wanting to improve/mod your mill, try the forum search function with "rf-30" in the search field and "hman" in the member field.  I've posted a few tips and tricks ... as have many others!


----------



## ThinWoodsman (May 30, 2019)

Dudemanrod said:


> Thanks Mikey im feeling better and more excited about this mill. Im planning to go through it all the way. Electrolosis seems like the way to go on the table. One step at a time



My favorite electrolysis how-to is Electrolytic Rust Removal aka Magic. I bought a plastic tub about 2' long, bent four pieces of rebar into an L shape (long leg down, short leg poking up), drilled holes to zip-tie the rebar, then ran wire connecting them together to an alligator clip. Very simple, lots of bang for the buck (a $3 box of washing soda will last you for years), and you might find yourself chucking everything with rust on it (which can't be all that many things, in Napa) into the bath.


----------



## Bob Korves (May 30, 2019)

When using Evapo-rust or electrolysis (or whatever), a fairly easy way to make a tub to soak stuff in is to either dig a hole to the proper size and shape to hold the part(s), or make an above ground tank out of plywood and 2x lumber, and then line either version with plastic sheeting to contain the liquid.  A snug fitting tank will need a lot less Evapo-rust, which is not cheap.  Electrolysis is pretty cheap to do, there is electricity to pay for, but washing soda is cheap...  Don't use acids for taking rust off of machines and tools that you want to look nice and hold their dimensions when finished.


----------



## Dudemanrod (May 30, 2019)

I like the idea of making a tank out of 2x. I'm leaning toward electrolosis for the reasons you stated less destructive. I wonder if I can dump the water and residue in the yard?


----------



## markba633csi (May 30, 2019)

The left over liquid can be dumped in the yard or drain, it's usually mild alkaline, non-toxic although you wouldn't want to drink it
I like rung fu with extra soy sauce


----------



## Bob Korves (May 30, 2019)

Electrolysis is cheaper, not less destructive.  The high pH is high (basic) but not enough to hurt anything.  Evaporust contains a chelating agent, which only attacks iron oxide, and is safe to handle with bare hands.  Both are considered safe, but both will put dissolved iron and other metals down the drain or in your yard.


----------



## Bob Korves (May 30, 2019)

Another relatively safe option for removing rust is molasses, but it is slooooow.


----------



## Moper361 (May 30, 2019)

My Father had one off these round columb tiawan mills when i was a teenager .

I made my first ever project on one for a first year apprentice mechanic assignment .
I disected a unit unjector from a 71 series detroit to show how the helix and plunger worked in a unit injector .I ended up getting tbe highest score in the tech with that project .that mill went on to make many a spare part on the farm and is still in use now. About 30 years on


----------



## miro (May 30, 2019)

Same as many of you - been using my mill for about 4 years and have learned a lot. I found that a 3phase motor plus VFD upgrade made it a much much better machine, operationally.
It lets me change speed without the hassle of belt flipping.  so I get to the best speed easily rahter than over or underspeeding the milling cutter.
The motor (3/4 HP)  was $30 and the VFD ( 1 HP) was $110 

But first get it up and running , then get some milling time under your belt, then do the upgrade

miro


----------



## pontiac428 (May 30, 2019)

miro said:


> The motor (3/4 HP)  was $30 and the VFD ( 1 HP) was $110



I love the idea, but my RF has a 2 HP motor.  3/4 HP plus VFD seems small.  Seems you're happy with it, how is it under heavier load?


----------



## Dudemanrod (May 31, 2019)

Ok guys I have separation. Now I'm cooking with wrong fu I'm cooking half at a time as you can see and wondering how long and if doing half is ok? Used sodium carbonate from home depot pool ph adjuster.


----------



## Moper361 (May 31, 2019)

Im keen to see how this goes .Am i correct in thinking you have the positive connected to a piece of re bar and negative to the table and using bi carb soda ? What voltage and amps are you set on to make this work im interested for future reference


----------



## Dudemanrod (May 31, 2019)

Yes the set up is what you say and I have it set to 2 amps it has a 10 amp setting but it's working on 2 so I'll see. Not sure how long to cook it though.  If anybody knows I would like to hear from them


----------



## Moper361 (May 31, 2019)

W





Dudemanrod said:


> Yes the set up is what you say and I have it set to 2 amps it has a 10 amp setting but it's working on 2 so I'll see. Not sure how long to cook it though.  If anybody knows I would like to hear from them


What were the ratio of water to bi carb soda and is there any other chemicals used


----------



## Dudemanrod (May 31, 2019)

1 cup in five gallons got it from home depot pool supply. No other chemicals. I will post the results to see what happens here.


----------



## ThinWoodsman (May 31, 2019)

Give it like 4 hours and then check it. Smaller, less rusted stuff you can do in an hour or two; really tough projects have to go overnight.

You're going to have a line at the halfway point, even after dunking the other side. It's cosmetic, can come out with steel wool or polish or whatever you choose for the final cleanup. Remember as soon as the thing leaves the electrolysis bath, give it a rub down with paper towels and a brass brush/000 steel wool to get that black gunk off, or it will immmediately flash-rust.


----------



## Dudemanrod (May 31, 2019)

Thanks woodsman I'll check on her now and get my brushes ready


----------



## hman (May 31, 2019)

Moper361 -

Caution!  You want sodium carbonate (aka washing soda), not sodium bicarbonate (aka baking soda).


----------



## Dudemanrod (May 31, 2019)

Yes that's what I used it came out nice. Just a little scotch night pads. I'm happy with it plus no chemicals


----------



## Moper361 (Jun 1, 2019)

hman said:


> Moper361 -
> 
> Caution!  You want sodium carbonate (aka washing soda), not sodium bicarbonate (aka baking soda).


Haha yes my mistake i had noticed that earlier


----------



## Moper361 (Jun 1, 2019)

Dudemanrod said:


> Yes that's what I used it came out nice. Just a little scotch night pads. I'm happy with it plus no chemicals


Any pictures of the part you cleaned up


----------



## Dudemanrod (Jun 1, 2019)

Hey moper361 got a lot of things going you  know make the wife happy and all that. Painting the house kissing everybody's ass so I can do what I really want to do. So I did 4 hours each side and it most the rust off but there was still paint in the t slots and the table ends. So I cleaned with scotch bright and there going in the bucket for one more session. Photos will follow when I'm done


----------



## Dudemanrod (Jun 1, 2019)

After soaking still need to hit that high spots. I like this method it's clean and less of a mess. Cheers


----------



## Bob Korves (Jun 1, 2019)

Dudemanrod said:


> After soaking still need to hit that high spots. I like this method it's clean and less of a mess. Cheers


Nice job on getting the rust off.  Hit it with some Scotchbrite and see if it meets your expectations.  If not, contact me and we will see about taking it to the next level...  Make sure to get some oil on it right away or it will flash rust.


----------



## Moper361 (Jun 2, 2019)

Im impressed looks good i will definatly be putting that method in the holding tank .When i was you g i used to restore a few vintage tractors but this mothod was not in the equation though i wish it had of been .We use to use molasases and water method which did work but slow and now were this effective .


Bob Korves said:


> Nice job on getting the rust off.  Hit it with some Scotchbrite and see if it meets your expectations.  If not, contact me and we will see about taking it to the next level...  Make sure to get some oil on it right away or it will flash rust.


Im impressed looks good i will definatly be putting that method in the holding tank thank you  .When i was youug i used to restore a few vintage tractors but this mothod was not in the equation though i wish it had of been .We use to use molasases and water method which did work but slow and now were this effective .


----------



## Dudemanrod (Jun 3, 2019)

Does anybody know the thread size for the flat small lube fitting on the front and back of the rf-30 table. The front one is ok but the back is buggered up and I can see threads in there. Do they sell those little lube fittings?


----------



## Bob Korves (Jun 3, 2019)

Dudemanrod said:


> Does anybody know the thread size for the flat small lube fitting on the front and back of the rf-30 table. The front one is ok but the back is buggered up and I can see threads in there. Do they sell those little lube fittings?


I have not seen a ball oiler that does not have a press fit mounting, if that is what you are speaking of.


----------



## Dudemanrod (Jun 3, 2019)

Yeah  thanks Bob I just got the messed up oiler out and they look like press fit I will measure and order some. I'm not sure how many are on this mill but i do see one on the vice. I have never really seen these so it's a learning process. I'm ready to start on the base. I think I will use klean strip on it and wrap in plastic for a few hours and paint in rustoleam.


----------



## Dudemanrod (Jul 2, 2019)

Speed change pulley bearings. Before I complete  destroy this friggin thing do they come off towards the bolt?


----------



## Dudemanrod (Jul 7, 2019)

Almost finished. Replace spindle bearings with angular type using Mikeys tutorial. Replaced pulley taper hearings SKFand tensioner bearings with the same. Had to build out my work bench a foot or so and just cleaned it up a little paint and soon we will see how she cuts. I need a couple hand wheels if anybody wants to sell me. I want a DRO and power feed next not sure which I should do first any suggestions ? I got this far because if this forum so thanks to all. Mark


----------



## Moper361 (Jul 7, 2019)

Dudemanrod said:


> Almost finished. Replace spindle bearings with angular type using Mikeys tutorial. Replaced pulley taper hearings SKFand tensioner bearings with the same. Had to build out my work bench a foot or so and just cleaned it up a little paint and soon we will see how she cuts. I need a couple hand wheels if anybody wants to sell me. I want a DRO and power feed next not sure which I should do first any suggestions ? I got this far because if this forum so thanks to all. Mark


Steady steady wins the race .Nice job on the mill looks like it will be better than new with a touch more fetling


----------



## markba633csi (Jul 7, 2019)

Good article here about washing vs baking soda and electrolysis:




__





						Baking Soda Vs. Washing Soda  as an Electrolytic Derusting Electrolyte
					

Baking Soda or Washing Soda for the electrolytic derusting process, that is the question. This aricle  gives you the answer.



					www.spaco.org


----------



## Bob Korves (Jul 7, 2019)

Dudemanrod said:


> Almost finished. Replace spindle bearings with angular type using Mikeys tutorial. Replaced pulley taper hearings SKFand tensioner bearings with the same. Had to build out my work bench a foot or so and just cleaned it up a little paint and soon we will see how she cuts. I need a couple hand wheels if anybody wants to sell me. I want a DRO and power feed next not sure which I should do first any suggestions ? I got this far because if this forum so thanks to all. Mark


Looks very nice, Mark!


----------



## Dudemanrod (Jul 18, 2019)

Vertical end play on my RF-30. I got the mill together and made some test cuts. Then when changing out the collet I feel the spindle move up and down. I know that can't be right. Do I need a bigger thrust washer? I used angular bearings that were a tad shorter  but made it up with a thrust washer. But this is like a sixteenth or so . I guess I tear it back down ? Anybody have this trouble?


----------



## pontiac428 (Jul 18, 2019)

Do you have spindle play, or sleeve play?  You can take the play out of the sleeve by closing the gap on the fine Z bevel gear.  Just loosen the bolts on the 90-degree gear housing, adjust, and tighten.  I did this over the weekend on mine, went from .020" play down to .004" and feel better for it.


----------



## Dudemanrod (Jul 18, 2019)

Hey Pontiac it is spindle play not sleeve play. I took great care putting this mill back together and operating it you have to follow methodical steps to get a nice result so I have to dial in my patience and not skip steps and check my tightening and good work holding protocol.  I wonder if this helped in my problem check thumbnail I know better but sometimes I do stupid things. I had a a small piece of 6061 in the vice and was not supported like a normal person would do and it was ok until I took a heavier  pass and it snapped that end mill like a twig. So i need to slow down a little and not do things i know are dicey.  I hope I did not do any major damage. That vertical end play has got my worried.


----------



## mikey (Jul 18, 2019)

I'm going to guess this play is due to non-existent preload. It is likely that your thrust washer is too thin. Make a thicker one and make sure the preload nut is actually applying pressure to the upper spindle bearing. The only vertical play that should exist is that allowed by the internal bearing clearances in your spindle bearings.


----------



## Dudemanrod (Jul 18, 2019)

Yea I took the the spindle out and the bearings themselves are moving up and down so I tightened  the nuts again put it back together and now I got side play so I'm wondering if breaking that end mill  toasted those bearings. I'm not sure if they were loose when I installed initially but you would think I would have noticed. As of now my 10 inch drill press has less run out so I may have a boat anchor here. There is threads showing when I'm tightening the preload so not sure a washer would help.


----------



## mikey (Jul 18, 2019)

If you used FAG angular contact bearings it is unlikely that breaking an end mill would break the internal cage; those bearings are very high quality. The threaded part of the spindle tapers at the bottom of the threads; you can still see threads showing but the nut may not be putting adequate pressure on the bearings. Your call but when I made a spacer for this purpose I made it 2mm thick and this was just enough to preload the bearings adequately. 3mm would probably have been a better idea.


----------



## Dudemanrod (Jul 18, 2019)

Thanks for your reply Mike I was just thinking thinking that that was also the cheapest end mill and and the bearings look good. You must be right I'm going to the hardware store and see what I can find. Thanks again I was feeling bad about being careless and breaking that end mill but I'm reenergized now to get this dialed in.


----------



## mikey (Jul 18, 2019)

Do you not have a lathe to make a spacer? Please tell us you are not lathe-less!


----------



## Dudemanrod (Jul 18, 2019)

Ok mikey you are awesome and I'm latheless but not for long hopefully. 3.4 mm got it tight no movement solid this will be subd out to NASA for skunk works projects. Unless that is to much shim


----------



## mikey (Jul 18, 2019)

No, 3.4mm should be just fine. You should have more than enough thread to accommodate a spacer of that thickness. Glad it worked out.

Being lathe-less is a very sad thing - gotta' fix that soon!


----------



## Dudemanrod (Jul 18, 2019)

Quite true on the lathe have wanted one for many many years. Mill also but got that now and a 9×30 or so something that I can park next to the RF then all will be Zen.


----------



## utson (Feb 5, 2021)

I'm new to all this posting and stuff, and in fact machining. Thinking about grizzly 1126 mill that has been in a fire and has been tipped over, needs lots of clean up. it does run.  my biggest concern is the tipping over part. anyone have some thoughts on that.
hope this post isn't in the wrong place.


----------



## Boswell (Feb 5, 2021)

I am guessing that it was not in a too hot part of the fire if it still runs. Check that the X,Y and Z axis all move smoothly. No breaks in the castings. Runs smooth at all speeds and don't pay too much.   
As far as forum etiquette goes, you will find that everyone is very forgiving  here. My suggestion is to create a unique thread for this discussion instead of using an existing.  Good luck


----------



## Aaron_W (Feb 5, 2021)

utson said:


> I'm new to all this posting and stuff, and in fact machining. Thinking about grizzly 1126 mill that has been in a fire and has been tipped over, needs lots of clean up. it does run.  my biggest concern is the tipping over part. anyone have some thoughts on that.
> hope this post isn't in the wrong place.



If it is really cheap it might be worthwhile, but it would have to be really cheap. 

Rust will be a major concern even in areas where you don't usually worry about rust, heat and steam (firefighting operations tend to make lots of steam) will have gotten moisture into everything. Many of the chemicals in smoke are also corrosive particularly when mixed with water into a nasty sludge. 
If you don't see signs of actual flame impingement, or other major heat impact like burnt off paint, melting of plastic and low temp metals etc then it may be ok. High heat can change the properties of the metal, and definitely compromises wiring so it is something to look for. 

The tipping over is probably the least concern. If mostly handles and such, those can be replaced. Cast iron is not easily repaired, so damage to the main body or table probably means it is best used as a parts machine.

Agree with Boswell, a new thread will get you more views / comments.


----------



## utson (Mar 1, 2021)

Thank you for your reply, i am fumbling around on this forum. I have decided against the burned up g1126.


----------

