I have a rebranded Rong Fu 31 (I think) that is hopefully getting off to a good start. I am open to do/don't suggestions on oiling etc.
Dumb question: for practice, I aligned my vice using a dial indicator. It was fairly smooth, but not something I would want to do every day. Should I be concerned about leaving the vice in place for long periods? I would hate to find rust where there was once a nicely machined table :(
Is there a trick to mounting an indicator on the spindle? I put it in a chuck. Is there a better way?
Speaking of the table, most of it is quite clean. There are a couple of small dings that I assume will be best honed or lapped away. What should I _not_ do?
Before even checking prices, I knew about the tool change, head height, registration woes of round column machines. I can live with it (670 pounds was quite sufficient for me and my engine hoist), but will welcome ways to reduce the hassles.
One of the more interesting suggestions was to use a collet chuck. My problem is that google returned so many hits as to be useless. Can some kind soul who knows what is going on provide a link to the right gizmo (or refute the idea)?
An edge/center finder is on its way. For most things, layout lines will probably be more than sufficient. Otherwise, I am thinking of drilling a reference hole for "when" I get lost, and then working relative to it.
That's common practice in machine shops, but if you use any kind of water soluble sprays or coolants, you could find some rust----or often a black discoloration. As long as you're working with oils and other hydrocarbon based solvents, I wouldn't worry too much about it, but be somewhat cautious otherwise. If your environment isn't rusting things now, there's little reason to expect rust under protected surfaces.
If you do any wood work on the machine (not all that uncommon), make sure you don't leave any damp chips behind. I've used my metal cutting machines for that purpose countless times with no problems, but I clean up well afterwards.
Not as far as ease of use. By using a chuck, you have something to grasp to position the indicator, which is important if you're sweeping in a bore or the table. You can mount directly in a collet, depending on the hardware you have available for your indicator, but that leaves you with little to grasp while you're dialing items where you have to rotate the spindle. Works fine for a vise or other things that require the table or saddle to be moved, not the spindle, so choose accordingly.
If you're familiar with draw filing, that's the way to remove dings on a table. A single cut file (best not a new one, which is usually quite aggressive) is placed on the table of the mill and drawn sort of sideways along the table with light palm pressure on the file. Given the proper application, it glides over the table with no consequence, but removes anything that stands above the table. Cast iron is very good about cutting away easily, unlike steel. If the file traverses the surface smoothly and doesn't hang up on anything, the table is clean. If anything stands up, you'll feel it. Just repeat the process until you don't. You'll be able to see where it was, and how it was removed to flush with the balance of the table.
Think ahead, and make sure that once you've established location and have your dials related to the part, make sure you don't have to move the head. Know what tools you're going to use, and make sure that the long ones can be installed and used, as well as the short ones. Where you get into trouble is using end mills in collets, then changing to a collet mounted drill chuck and using large, long drills and reamers. You run out of spindle, which is the chief reason I hate mill drills. On knee mill, you can move and not lose registration. (Not trying to be rude here)
Unless you intend to stay with the machine for the unforeseen future, or if you intend to use it for gain, where time is important, I think I'd stick to collets and not worry about it. One of the negatives of using any kind of quick change is that you generally add to the length of the spindle, costing you rigidity unnecessarily, but even worse, valuable space. You'll have limited height to begin with. I'd strongly recommend you not reduce it any unless you have good cause.
Not in your table! Good machinists don't drill holes in machines------especially not by choice. As long as you have a method of locating your part as it relates to the spindle, just make it a habit of always doing it a particular way. Should you get lost, you can go back and start over. You'll use your edge finder or a wiggler, or even an indicator, depending on the setup. That's no different from a hole, which you'd have to relate to in the same way. Lost in this? Did I not understand the hole concept? Maybe you have a thought that got past me. Lets talk about it. If you aren't familiar with typical shop practice, maybe you can find someone locally that is a machinist, or at least has some experience so he/she can guide you. Otherwise, it's best to ask for more information here. Ask specific questions if you're stumped. There's way too much information to dispense to give answers that you have. It won't take you long to figure things out with a little guidance from this group of people. Many are machinists by trade.
Most people I know leave the vice in place until they need the complete table area.
I wouldn't do anything to them. They are highly unlikely to have any effect on the operation of the mill.
My (old Centec) mill came with a Clarkson chuck. I found it was a real chore to have to remove it for drilling. I've now got an ER32 system which can securely hold any diameter from 2-20mm. It can be used to hold drills as well as milling cutters. Since you mention 'pounds' somewhere else I assume you are in UK. If so, take a look at RDG Tools' website for reasonably priced ER sets.
formatting link
Although pricey, consider installing a DRO system. Trying to compensate for backlash on a mill can quickly destroy any pleasure derived from making chips. If you take that route, don't skimp and settle for a
2-axis system - you will soon wish you had 3. I listened to the advice of several model engineer friends, and they were definitely right.
Harold, I routinely do just this thing. Except, oil the table and use a stone. Dropping items on the cast surface or clamping steel directly to the table will raise a very small dimple. The stone removes them nicely.
You can make a key that fits the table slot and mill a shallow groove in the underside of the vise for it.
The RF-31's table slots had been cut at a slight angle to the X axis. I fitted the key to the table first and milled its top edges slightly narrower to make them parallel to the table motion. Then I clamped a piece of ground stock to the table, indicated and adjusted it true, clamped the vise onto it upside down and milled a slot to fit the key very snugly.
I have a RF45 clone and I disassemble it completly and cleaned it after uncrateing it.
Got *lots* of grit n grime out of the nooks n crannies that the factory includes--- at no extra charge.
. In regards to losing the register some have suggested using a small inexpensive laser mounted on the head to relocate after moving the head. Not sure if its accurate enough..
The only modification I plan on is to replace the 1ph motor with a
3ph and a VFD for better speed selection. I chose a power feed over a dro for a option but will add a dro later.
The tooling requirements seem to be nearly endless. I have an equal amount of $ in tooling as I spent on the basic machine. BTW I really enjoy mine and it does very nice work. If I upgrade to a bigger mill it will be a horizontal..
There is a yahoo milldrill group that might be a source of info..
Couple of things: The "loss of center" when moving the head vertically, is one of the major drawbacks of a mill-drill. Reasonable location can be re-established via good layout lines and/or an edge finder from reference edge(s). Get a Blake, or clone, co-axial indicator for accurate re-location of critical holes, or location from a datum hole if you want to use one. With a little practice you will forget about the loss of center problem. A lot of it can be overcome by carefully predicting maximum tool height required for all tools used (vertical clearance) for any specific job.
Don't bother changing out the motor to 3-phase and getting a VFD. IMO, it's not worth the expense. Moving belts on pulleys isn't that big a chore; besides it gives you good experience in estimating speeds and feeds for various materials. Save your money for R-8 tooling for the mill-drill and the "Bridgie-clone" in your future.
FWIW, I have both. Usu. the old mill-drill is relegated to drill press work but occasionally I use it for more critical stuff. Recently, I made a pair of steam engine eccentric straps on the mill-drill. I sort of did it as an exercise to see if I "still had it" on the mill-drill. It worked out OK with some belt changes and co-axial centering required but overall it was a bit clunky compared to my Bridgie. That's because I am more used to the big mill with all its conveniences. The mill-drill still has a place in my shop. You have some great experiences coming up with your mill-drill. Consider it as affording you some apprentice training before you get a full-featured mill. Take your time; concentrate on accurate layouts; take pleasure in the fact you have a real milling machine at a very reasonable price.
I disagree. The 2hp motor that came on my Jet mill drill was a real POS. I went through three of them before giving up and buying a leeson motor. THe single phase motor makes the whole machine jump when it starts. The VFD starts very smooth. I also could not get a nice finish with the single phase motor. This machine can now mill a slot with a nice finish using the side of the endmill.
To protect your nice new table, get some black floor runner from the hardware store and cut some pieces that cover the table next to the vise. This prevents dings when you drop something and might even save the corner of an endmill if you drop it. It also provides a nice place to put thing and prevents them from going into the T slots.
All good suggestions -- heed the advice about getting a 3-axis DRO as it makes all the difference. Mitutoyo sells a DRO bundle (I bought mine through J&L) for 8x30 machines that costs about $900 when it's on sale. I know that sounds like a lot for a mill-drill, but having to deal with the tiny dials and backlash costs something too - your time.
Buy a jug of real way oil (Mobil Vactra #2 or equivalent) to lube the ways and lead screws. Regular oils don't stay in place. If you are worried about rust, mix up some WD-40 and LPS-3 in a 4:1 ratio, and spray it on all of the metal surfaces after you clean up or before you mount the vise. And speaking of vises, don't even think about getting one of those $99 Chinese boat anchors. Buy a real Kurt vise and you will thank yourself every time it's used.
Note that the cost of all these suggesti> I have a rebranded Rong Fu 31 (I think) that is hopefully getting off
Chuck sez: "I also could not get a nice finish with the single phase motor.. . . "
Musta been something else wrong as well. Come to think of it, I did replace the original set of belts with a "USA made" set. (Thanks to Grant Erwin for the suggestion) That helped a great deal with the vibration problem. Hard to imagine you went through 3 motors, though. Maybe it was a "Jet" thing! My mill-drill is an old one, Wrong-fu, I think. I can not imagine any problems such as you mention that could be caused by only the motor. Anyway, glad to hear all is well with VFD power now. At the least, you have to think it is OK after spending all the bux on a VFD!
The RF45 is the dovetail column with a gear head, no loss of position when raising the head, pretty solidy constructed. The column was aligned dead nuts on when I indicated it, a pleasant surprise.
The gear head has a few speed gaps that need filling, the origional motor runs nice but sometimes a little lower/higher speed would be nice. It's R8 tooled so I'm good there, I live in a remote area with no used machine tools. The shipping for a bare used machine was more that I paid for my free freight enco RF45 clone .So I elected to use the difference for tooling.
I'm looking forward to winter and some extended chipmaking time. I schooled on big industial iron 30 years ago, I must have had a good instructor as everything has come back with litte reference to my notes, We didn't have any dro's there, I was taught to use a dial indicator for high tolerance positioning. I never have used a dro.
VFDs really are not that expensive. About 200 bucks for a new Teco. The convenience of variable speed and the soft start are totally worth it. I have several in my shop now and will probalby get another one for my Clausing Horizontal Mill.
I am totally convinced that a 3 phase motor runnning on VFD makes much smoother power than a single phase motor. If you set up the motor parameters correctly, it will protect things better than a plain overload too. If I start my rockwell mill in back gear without disengaging direct drive, it grunts a bit and stops. I suspect it would shread the tiny drive belts if I was using a RPC. If I turn the speed way down and stick a drill bit, the VFD kicks out instantly.
disclaimer. My mind is already made up; Don't confuse me with facts! :)
If you have a proper RPC, set up and trimmed out ala, "Fitch", any equipment running on it will not notice whether the "power" comes from genuine 3-phase or from a RPC. I have oscillograms of equipment running under load from a RPC and commercial 3-phase power. You can't tell them apart.
The plan is for lots of woodwork in addition to simple electronics fabrication and, over time, lots of Al plates with tab A one side and slot B on the other.
Is there such a thing as a preferred end mill for mortising?
My first attempts will be on some test pieces vs. the table, but that sounds like a plan. With some luck, my table saw might have a blemish in a harmless location.
No offense taken. The whole time I was wrestling the mill over the 30 ft from my driveway to its current location, I was feeling pretty good that I did not go for the knee mill, at least not right away - not that I would even attempt to move one myself.
I suspect that where it matters, I will have height to burn because the parts will be small. But I could be in for a surpise.
I've never knowingly drilled a hole in a machine (I once discovered one in a shared vice and had to wonder) and have no plans to do so. Rest assured I mean a reference hole in the work piece.
Only the bit about drilling a hole in the table ;) I'm following fairly well, but am not sure about using a dial indicator to locate relative to the part. It sounds like a good way to go. In studying the mill, I have been getting ideas of making some kind of clamp to grab the head/spindle/quill/column to hold an indicator. Is it easier than that?
The indicator could be on the table, but how would I create or find a good target on the spindle? There are very few flat surfaces up there, and I fear the curvature would make for large errors.
So far, I'm even a little nervous about even having room to change collets over a work piece. That might complicate using an edge finder. Milling with the spindle significantly extended probably has a role in the solution.
I'm starting to figure out the latter. Actually, I am overdue to visit the gentleman who taught me the little I know.
As well as a miniscule portion of the table that was in good condition. It's important that the file used not be new, which I mentioned. A slightly dull file will remove any highs, but otherwise leave the table untouched. If, by chance, it's prone to cutting, the file is too sharp. A stone doesn't do that, although I'd agree that what is removed is miniscule. Trouble is, if you're one of those neurotic types that is constantly dressing the table, the affect over a period of time is detrimental, due in part to dressing the area where one tends to concentrate use far more than, say, the ends of the table. . The only place I ever touch a surface with a stone is if I drop something on my chromed ways---at which time I'll generally use one made of a silicon carbide, preferred for it's greater hardness.
Best policy here is to wipe the table with your bare hand. Anything standing up is generally apparent by feel. Dress only when necessary, especially if a stone is applied.
DRO's are an incredible device, but my honest opinion is they cheat the user out of a proper learning experience. Having been trained as a machinist in the late 50's, no such devices were at our disposal. I learned how to run machines by applying skill------skill that will always be with you, much the same as hand grinding HSS tool bits. When you learn to machine using such devices as insert carbide and positioning devices, you tend to short circuit that portion of your learning, which often leads to a lack of knowledge needed in other operations. It's something that has the potential to haunt you endlessly.
Backlash is a non-issue. The only time it matters is if you climb mill, and the machine is too loose, or when you don't understand how to work with it, which one often doesn't when a DRO is used.
Having worked in the trade for years, I can say, with total honesty, what scrap I've made isn't attributed to backlash---it's from making other stupid mistakes.
I'm proud to say, I have NEVER used a DRO, and I've done a ton of work with tolerance restricted to a thou in many instances. A good portion of my work was building tools.
Did I mention all my work was subject to proper inspection by a an independent source? I couldn't fake it.
I tend to agree, but eventually I will need to clamp something over them. Harold's draw filing idea is well taken, but I will blend the two and get some practice first.
Having read two thoughtful responses I am willing to reveal the _real_ reason I asked: I wanted to see whether you agree that is largely ignorable. The bandsaw I bought with the mill, that's another matter; what a disaster :( I can't talk about it right now :)
I have many friends on that side of the pond, but I am a few generations away from a west-bound boat to the USA. Hopefully a search will reveal that I mentioned pounds in the context of weight.
Found it. Sounds like $270 US or so, which I am more than willing to consider, either from them (they apparently ship anywhere) or elsewhere. Amazon's offerings include the "Hertel HR8ER32162 Er32 R8 1-5/8 Proj L Collet Chuck". Somehow it looks like it's missing the collets themselves, which probably explains the price difference.
Ok, I will admit that when I first read this I thought you were giving me a bad steer, but being overwhelmed with the helpfullness of this group, I figured it couldn't hurt to look. So are we talking pricey as in $700 US? I agree that is a lot of money, but considerably less than I expected.
The URL I have is
formatting link
Any horror stories ordering from them? I won't be doing this in the next week or so (trying to convince myself, not you).
I would argue that if I can't solve the registration problem (which I fully expect to do within my tolerances, in both thousands of an inch and patience), then a DRO would tell me little beyond the location of the table. No offense intended gang: I am interested in your thoughts on the matter.
Thanks for the advice; I will probably end up with a DRO. I think I will take to life with a mill/drill, but figure I should use it for a while before spending a lot more money on it. If I am "forced" to get a knee mill, I'll wish I had saved the money for movers.
Besides, some dial reading will do me some good; it's been a long time.
With a long enough travel (perhaps involving mirrors) it could be very accurate provided the "stationary parts" are indeed stationary.
Interesting. I don't mind the belts except for one thing. I have it set up just below the point that requires me to tweak both belts to get more speed.
I bought the feed with it. The longitudinal travel is a bit long to be without it. Two small gripes: it needs to come off to reach the oil port on the left side (seems they could have drilled a hole for that???) and manual operation is a little uncomfortable with it present, even off and in neutral. Am I missing something on the latter?
That sounds about right.
I'll bite: why? I learned (if you want to call it that) on a vertical so I might simply be biased.
It appears to be, but every time I try to join a Yahoo group, I get static. As an aside I belong to one Yahoo group, and my spam when up by orders of magnitude shortly after taking that step.
There DE! You heard it from the horse's, errrr, welll mouth. Thanx Harold. The great unwashed and inexperienced set can learn much from old heads like you. I am happy to hear you never used a DRO and still did tool-grade work. That statement presages a vast amount of honesty and no small amount of pride, I'm sure. We should all have your experience but 'taint no way, no how, not in this lifetime! So, Harold, now that we are on the soapbox, give us your take on those that purport to jump right into CNC with absolutely no manual experience. I suspect they are mostly computer programmers (or less) that believe all they peck out on a keyboard can be easily done in the physical world.
PolyTech Forum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.