Don't worry so much about the round column thing. Much hot air has been expelled by guys that have never used one, but think that they should be able to get the capacities of a full size mill and the accuracy of a jig borer from a sub-$1000 import tool.
For the most part, as a hobby guy, you will be doing layout and cutting to a line. There are ways to find the center of a hole, using a dial indicator, that take a few minutes time, but are not the end of the world to learn, and there are ways to think through your setup so that changes from long tools to short ones can be minimised. I have used an RF-30 style and size of round column mill, and found that with care, cutting a line to an accuracy of a thou was possible, though not something one achieves in a hurry.
The mill you are looking at on the other hand, looks a little TOO lightweight, even by import mill standards. They are listed at $360 or so brand new. Up to you to decide what will meet your needs.
My recomendation is to look at tooling and upgrade path options over a longer term. If you buy a mini-mill with an R8 taper, some of the tooling you buy for it could still give you good service 3 or 4 mills down the road, on a full size Bridgeport, should you ever go that far.
yeah, I guess i'll let this one go- in my price range, but probably not going to do what I want it to. And if I can get in touch with gunner about that mill he was talking about, maybe I can get a better bang for my buck. Wish I could get ahold of one before Christmas though, I always prefer giving hand-made gifts (alas, so few children appreciate a good algorithm!), but I guess I'm probably better off with no mill at all than 300 in the hole and trying to ditch something that won't cut it.
LoL actually I kinda was thinking about that- I have a little cousin (~5 y.o.) who just adores anything mechanical, and I was thinking that maybe I'd make him a little flywheel car or something. I mean, I can still make it, but without the ability to make gears I'd have to settle for pulleys, which he finds much less impressive. I am beginning to think (always dangerous) that I'm probably not going to be able to afford a mill on what I've got, but one of the minilathes might be within the realm of possibility. Do you guys know if its really any harder to make gears on a lathe than on a mill? Or am I trying too hard to cut down the costs? Thanks again, GCC
Look, you can make almost anything with a lathe. Question is, what's your time worth in doing the setups and coping with lack of rigidity? Have a look at Lindsay Books and buy the Gingery book on building your own dividing head & deluxe lathe accessories. It's got a lot of good info aimed at someone without much of a shop. There's an Argus Publications book on dividing & gearcutting in a lathe too, and the lathe used was a Myford which is not very big/robust.
What size/pitch gears are you thinking of making? If they're tiny, small stuff will do. If you're wanting to make 10DP, 8DP or coarser - I don't think so. You'll need a decent machine. Don't even *think* about herringbone, spiral or anything except straight cut spur gears. For them you need either a CNC machine or a universal mill with dividing head rotation geared to table travel.
Are you going to make 20 PA gears or 14.5 PA gears? They're not interchangeable and the cutters are different.
You'll need a lathe to turn the gear blanks to size. Lathe size depends on desired gear size & material. For accuracy you'll need to do both the inside diameter & outside diameter in a single setup, or have a way of setting the OD true to the ID. Dial test indicator & 4 jaw chuck or collets, or tapered arbor on centres. Also useful for the tooth cutting part in the mill as you need to maintain concentricity.
At minimum you need some form of indexer, which can range from another gear with a stop to a differential dividing head. You *have* to set the centreline of the gear cutter on the highest point (ie top of radius) of the gear blank, so the dial test indicator will be needed here too, most likely. I have my methods, other people have theirs.
You'll need gear cutters which come in sets of 8 per diametral pitch, and are *not* cheap, or you'll need to learn how to grind a single point cutter to size, or I think there's an article by John Stevenson in the metalworking archives on making involute cutters, but you needed a fair amount of stuff too.
How are you going to secure the gears to shafts?
A horizontal mill is the best tool for doing this, and they're very robust units. I think that you're being very unrealistic thinking you can get into metalworking for a few hundred bux, tho. I paid more than that for my dividing head. If you hunt down deals, a thousand or so is probably do-able as a starting point.
It's not hard to make a gear that goes round & round and transfers motion. It is quite difficult to get one which meshes properly with another gear from a commercial supplier and runs quietly at speed. Well within the realms of a home shop, for sure, but don't underestimate the skill involved (and tooling) to get there.
It has been, and will continue to be done on lathes. Watch and clock makers have been cutting gears with their lathes for just about ever, and modellers the world over have been so doing as well.
It represents an ability to accomplish much with little, out of sheer necessity.
If I may be so bold. Hold off on spending the money on a machine or machines, until you do a bunch of reading, and familiarise yourself with the possibilities and limitations of taking certain paths.
If you can find a library with a collection of back issues of Home Shop Machinist magazine, that would be a good start. One with a collection of Model Engineer magazine would be a treasure indeed.
To have such as them in hand, is to be able to reap the experience of many who have gone before, complete with pictures of setups and explanations of tools and tooling that are going to be either wanted, or required, in order to accomplish an end.
I would suggest a couple books worth a read. If you do not wish to purchase them, look at the public library, and see if they can bring them in on an inter-library loan.
Practical Benchwork for Horologists by Louis B Levin. A good book by an American author with a history in watch and clock lathes (Levin lathes are quite a well respected product, same Levin). Shows a lot of setups that allowed a watchmaker with limited tooling to build what he needed. This one is a good read, with a decided slant towards a watchmakers world, but it has some good info. I'd suggest this one from the library, then see if you think it worth buying.
How to Run a Lathe. By the South Bend Lathe Co.. A Keeper! Under $10, too! Buy it! (If yer real cheap it can be found online, but it's worth buying!)
The Amateur's Lathe by Sparey. A British book aimed at beginner model engineers (britspeak for home shop machinists). Much good info showing set-ups and problem solving as well as a decent amount of drawings of tools to make. Mostly shows Brit lathes, with an emphasis on Myford, but applicable to any lathes, generally.
Milling in the Lathe, and Workholding in the Lathe. Both by an author that wrote under the name Tubal Cain (T D Walshaw, in fact). Part of a series of books sold as "The Workshop Practices Series" Good books.
These are books that I have bought and kept because I always seem to find something new in them each time I go through them.
There are lots more books out there, too.
It seems to me that you are not quite sure of where you are going to go with all this. As there is a lot more invloved to getting a project made than simply having a lathe or a mill on the workbench, I would suggest caution, if only to keep you from dropping all your money on a tool that does not have the tooling or capability to do what you wish of it.
The main thing most lathes lack, and is essential for gears, is indexing. A minilathe has no indexing capability without adding something. Frankly, if gears are your primary interest, you want a mill. Almost any mill will do. As someone else said, a horizontal mill is ideal. If you are patient those pop up pretty cheap from time to time. I just bought one for $75. Needs work, but I could have it cutting gears pretty quickly.
Backtracking a bit, you would still want a lathe to turn your blanks to size. And you want some sort of indexing tool to get the proper gear tooth spacing.
So, minimal tools for your needs:
Minilathe at ~$350, or almost any used metal lathe. Gear blanks do no generally require ultimate precision, so a worn unit with no gearbox or change gears would probably do. for that matter, for aluminum gear blanks you could probably pick up a grarage sale Dunlp/AA/109 for less than $200. Maybe much less. I bought 2, for $50 and the 2nd for $12.
Milling machine - Minimill at $400, or almost any small horizontal mill, or vertical mill. You will also need some tooling, such as a flycutter to hold a single-point bit.
Indexer - these can get expensive. You can probably get a small rotary table with indexing for $200 Here's how to make one
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you have a collection of gears, you can use them as a basis for a shop-made indexer.
There are a ton of old articles you can download that show how to make gears. Most all of them tell how to use a lathe to do it. Send me an email to burkheimer at earthlink dot net and I'll send you all the PDFs you can stand.
Ok, let me clarify one thing, and then I'm going to ask some stupid questions rapid-fire and just get them out of the way:
To clarify: I do not have the necessary cash, experience or knowledge base to simply leap into making the things I want to make. I know that. But I have to start somewhere.
On to the stupid questions:
1) I was thinking with the lathe that I could wind up just mounting a rotary table vertically on a compound and use an involute cutter for the actual cutting- stupid?
2) People keep talking about the gingery machines. I'm not going to lie, I have no intention of casting my own lathe- but building a mill with a lathe seems a significantly simpler task. Am I wrong in that?
2) Thus far in my searches, the lowest prices for machine tools in my area I have come up with are ~$200 for a minilathe and ~$500 for a minimill. I don't mean to get above myself, but I'm a smart guy, and very capable with my hands- I am sure I could eventually figure out (with the help of everyone I know who's ever so much as handled a drill bit) how to use these tools to do what I need them to do, and if nothing else, I will need them both eventually. My question is this: which tool will help me get into a position so that when I have the cash I will be able to do what I want?
Again, long-term, a horizontal mill sounds like the tool for me, and I plan on keeping my eyes open for them- but for right now I need to understand what the hell I'm doing, and it sounds like a smart way to do that would be to read everything I can, use that knowledge (and, if my ever-charming nature and nigh-limitless knowledge don't inspire hatred, ya'lls advice ;-). ) to buy a machine, learn how to use a machine well, whether lathe or mill, and then start looking towards what I really want to do, probably 1-3 years in the future, presuming that I'm not impossibly stupid.
Short-term, though, I'm willing to screw up some- so long as I don't actually wind up wasting money. I'm willing to spend money on tools and tooling I don't need right now, so long as they will serve me in the long run, but I have to balance that with what I could have spent that money on. Its not actually the snake oil or the jackalope hunts that bother me- its the fact that while I was off buying snake oil I could have walked right up the road and bought some penicillin- not that it would have done me any more good, because I would swell up and die, but you get the point.
Having written all of this, I hope it makes some degree of sense, but the bottom line is, I'm trying to learn how to do this stuff. If I can get just the right tools- sweet. If not, well, better to start now and keep learning, than to twiddle my thumbs, knowing that even if I get the best deal there is, I won't have a clue what I'm doing. GCC
You don't need a rotary table, just a means of indexing. Look at the SB and Atlas lathe books and they will give illustrations.
Build a mill if you want the fun of building a mill, not to get a working machine.
My question is this:
Not to sound smart, but any of them. You can usually find a way to do it with what you have.
right now I need to
Good plan.
buy a machine, learn how to use a
As bizarre as it sounds, the more you know, the less you need the machine.
My advice, guaranteed to be worth what is costs, is to hold your money and wait for a target of opportunity. Work out beforehand how you will transport the machine to your shop. Have a space for it. If the machine is a lathe, good; you need one. If it is a horizontal mill, you need one, too. Vertical mill shows up in Craigslist? Chinese? Maybe, if it's _really_ cheap. You can grab whatever because you will be ready to do so.
There are machines all over. People retire and move. The rust belt businesses that moved south go CNC. They are there, you just don't know where yet. I can also guarantee that as soon as you get yours, another half dozen will pop out of the woodwork.
You have the jones for a new toy. For now, chill. Buy some files and a hacksaw. Learn to use them first. Stick around. The physics of Karma will bring a machine to you.
I'll go out on a limb and say that if you only have one machine, have a lathe. A lathe can provide you with round surfaces, flat surfaces (look online for the terms "milling attachement" and "vertical slide"), and threads so you can, for instance, build a pretty brass or hardwood box with a screw on lid.
I'll also stick to my suggestion that you budget for at least a couple good books. I am partial to the British model engineering books, as they tend towards an acceptance that one does not always have the equipment on hand that one would like, and that there is much to be gained by making ones own machine accessories.
Take a look online at
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for some decent info.
Check out
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too. Just because it shows it on one machine, does not generally restict the applicability of the information to that particular make.
Here is a picture of one way to cut a gear on the lathe, using a dividing mechanism (it need not be as fancy as this)
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It is worth noting, that effectively, the lathe is being used as a horizontal mill, just not a very rigid one.
...and Kevin isn't joking. You can actually do a heck of a lot more than some people would think with those items. Not being capable of doing it, or simply not thinking to do it (the must-have-massive-machine mindset) can make for a heck of a lot of needless work.
You need the cutter at right angles to the gear blank. Sure you could do it provided there was sufficient clearance for the cutter could travel past the blank without fouling the RT. There's a reason dividing heads etc are low profile, FYI - it's a cutter clearance issue and a rigidity issue.
Personally I'd spend money and buy machines. Lotta work in making either, and I've got all Gingery's books plus a lot more comprehensive shop.
BOOKS!!!!! As you've already been told by a lot of people. Buy some goddam books, read them, absorb what they're trying to impart and THEN buy some tools. The books are the cheapest investment in this hobby you'll ever make. If you don't do it, I don't care how smart you
*think* you are, you're demonstrating overweening arrogance in thinking
*you* can pick up the art by bumbling through and asking questions on a n/g. I for one will rapidly stop answering.
Buy a lathe, learn how to turn round, parallel & concentric. Learn how to turn to size ie how much your dials etc lie to you. Learn to measure accurately. Learn how to make 2 things the same size. Learn how to sharpen tools. By the time you've done all that you can start on something more complex. By all means break some stuff & ruin a ton of parts, it's allpart of the learning process. You're gonna pay your dues one way or another tho and while you might think you won't, there are lots of smart people here who've been thru the learning curve.
If your budget really is only a few hundred, good luck. I'd buy a lathe myself. The smallest one on the Grizzly web site is the G8688 and it has variable speed down to 0 rpm. Still over $500 tho. The next 2 models up I personally wouldn't buy simply because their lowest speed is gonna make threadcutting real exciting for a beginner and tool crashes into chucks don't do a lot for the learning curve. After those you're looking at close to $2K. TANSTAAFL. Pay cash up front or pay by learning the idiosyncrasies of a used machine. I've always done the latter and it's been a lot of fun sometimes.....
Sounds like good advice. Quick question- is there an advantage to a dial caliper? I'm finding that the digital ones are actually cheaper around here. Thanks again, y'all. Especially for the book suggestions. GCC
I'm rather partial to vernier, myself - simple, rugged, ought to be cheapest, but often are not these days due to marketing.
The downside to vernier is the potential for mucking up the reading, which is reduced somewhat by both dials and digitals. But with practice that becomes less of a problem. If you really want precision you need to learn to read verniers anyway, as you'll want some micrometers. But digital readouts can be a godsend for old eyes.
The downsides to digital calipers, IMHO - how many 30 year old chunks of electronics are you using, which are good as new? Now, how many 30-100 year old manual measuring tools are (or can easily be returned to) good as new condition? What do they think of oils, cutting lubricants, solvents, etc...? So it's a disposable purchase more than it's a tool investment. And you need small irritating batteries, each of which will cost a significant fraction of the price of a cheap Chinese import digital caliper, if that is the market you are feeding in.
The other problem, particularly for newbies, is the cognative dissonance between accuracy and precision. We'll hope that you're sensible enough to get a stainless steel unit, as opposed to the "composite plastic" sort which are cheaper yet. Now, if your caliper tells you that something is a particular size to 4 decimal places, do you think it's that size? Really? Based on what?
Pay strict attention to these comments------especially the one about reading decimal dimensions to 4 places. Ain't gonna happen------not with reliability. Trusting calipers for precise readings is not a smart thing to do, particularly if you're going for critical fits. Calipers (vernier, digital or dial) should be used for approximate readings only.
didn't say I wasn't buying books- was just on half.com looking for them in fact- just said that I learn better by doing. Don't tell me that you learned everything there was to know about metalworking before you touched a tool, and I won't tell you that I can learn everything there is to know without picking up a book. No need to get grumpy. GCC
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