Announcement

Collapse
No announcement yet.

Beginners Mill

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Beginners Mill

    I need to mill and drill some parts for a startup business, being a startup budget is limited and very limited space. What I need to do seems simple, although I have never done any milling before, basically rounding off some corners on 6063 aluminum and mild steel, making a 1/2" deep x 1/4" wide channel through 6063, drilling 3/16" holes in mild steel and aluminum for mounting pins and a few other minor cuts. I'm sure things will expand as I learn what I can do with a mill. My first thought is a mini mill like what Harbor Freight offers. I'm having trouble figuring out what is the next step above these mini mills without purchasing some 300lb or more behemoth that I don't have the space for right now. Any suggestions?

    On a side note I have found this forum to be extremely helpful to the novice. I've found books and just a lot of general information about milling that I obviously didn't know since I've never done it before. Everyone seems to be open minded and I don't see a lot of big ego's on this forum like I find on some other forums (non machinist forums). It seems like people are very willing to share their knowledge and accept there are more than one way to accomplish the same thing.

  • #2
    I'm currently shopping for a mill as well. Let me give you some advice I've learned from years of buying "things". Buy bigger than you can ever imagine yourself needing. You "think" you'll only be doing this and that, but you'll soon be doing more than you think. Especially with a tool as handy as a mill. Don't get me wrong, I'm not saying you have to go out and buy the biggest machine you can find. But don't buy the smallest one you think will work either. Choose what's right, then bump up a size or 2, you'll be glad you did. And it's cheaper to buy a little larger now than to buy one, realize it's too small in a year, then have to sell it an move up. Trust me.

    BTW, same advice applies to trailers, tractors, motorcycles, welders, oxy/act tanks, bar-b-que grills, tv's, computers and a bunch of other stuff.

    Comment


    • #3
      300 lbs isn't very big....

      Check out www.grizzly.com if you haven't already. (n.b. this isn't necessarily an endorsement of Grizzly, it's just that they have quite a range of milling machines to look at.)

      By the way, milling a channel is not necessarily a trivial operation. If you're concerned about accurately holding the width, you'll probably need to do it in at least two passes, one undersize (maybe 3/16" or 7/32" wide) to clean out most of the material, then a finish pass to get it to size. Otherwise, the end mill will get deflected and cut oversize. You'll probably need to do several passes to get the 1/2" depth, too. Plus, if you're doing this on a lightweight mill, it will take even more care. Cutting metal, even aluminum, takes a LOT of force.

      What radius are you wanting to put on the corners of the aluminum? If it's a radius of any size (say, 1/8" or more), once again you may find the task a bit daunting on a lightweight milling machine. It can likely be done, but there is no substitute for weight and rigidity in a milling machine.

      Are there any machine shop night courses at any local college or school near you? If so, enrollment to get a little hands-on experience will teach you more about what to consider and what matters in a milling machine than any amount of questions and answers.
      ----------
      Try to make a living, not a killing. -- Utah Phillips
      Don't believe everything you know. -- Bumper sticker
      Everybody is ignorant, only on different subjects. -- Will Rogers
      There are lots of people who mistake their imagination for their memory. - Josh Billings
      Law of Logical Argument - Anything is possible if you don't know what you are talking about.
      Don't own anything you have to feed or paint. - Hood River Blackie

      Comment


      • #4
        First, bear in mind that this is the babbling of a rank amateur...

        As SGW said, 300 pounds isn't very big. Think of it this way: The amount of time to mill a slot is inversely proportional to the size of the mill. In other words, a small mill will work, it will just take longer. Since you are talking about a business, time is money. I have a small, 30 pound, mini mill that can mill your slot...it will be an all day job. You want a bigger mill.

        Space permitting, you could get a really big horizontal mill for next to scrap value. Optionally, depending upon the length of the slot, you could get a shaper. Some people can't even give away a large (>2000 lb) shaper. A shaper that size would be extremely cheap and it shouldn't take too long to make your slot. Transporting it could be a big issue. But, if you have to live within 300 pounds, maybe a 300 pound mill/drill with a rotary table and power feed would work. You could use the rotary table to help make your radii and the power feed to set the machine to cut the slot so you can go walk away and do something else instead of sit and turn handwheels for hours on end.

        Depending upon the required accuracy of the holes, you could locate them with a jig and drill them on a cheap drill press. The jig could be created by using a cheap surface plate, height gauge, some dye-chem, an optical punch, and a drill press. I don't know what your tolerance is; but, there may other ways to do this cheap and fast. I also don't know what your budget is.

        Anybody feel free to correct my babbling.

        Regards,

        Brian
        There are only 10 types of people in the world: Those who understand binary and those who don't.

        Comment


        • #5
          Oh, yeah, I'll second the thought about grizzly.com. They have, perhaps, the largest selection of machines in one place with many of the manuals and specifications on their web site. While looking for machine tools, I used them as a library.

          Brian
          There are only 10 types of people in the world: Those who understand binary and those who don't.

          Comment


          • #6
            You can drill holes in mild steel with a drill press, and those can be purchased or borrowed for next to nothing, much thicker on the ground that mills. Aluminum in a one off situation can be milled with a router. Then you can save up till you can afford a Bridgeport.

            Comment


            • #7
              No such thing as a beginners Mill. You start making chips and it just snow balls from their. Bigger mill bigger lathe more tools . More machinery . It never stops Please make it STOP. More this more that. I want More Tools. Helppppppp. Join the funny farm . Good luck,and have fun.
              Every Mans Work Is A Portrait of Him Self
              http://sites.google.com/site/machinistsite/TWO-BUDDIES
              http://s178.photobucket.com/user/lan...?sort=3&page=1

              Comment


              • #8
                I see everyone's point and I appreciate the advice. I have a few other hobbies and I learned from them that cheap tools take twice as long to use and usually don't do a good a job. I guess I need to use my own experience as a lesson. I think the problem is I had no idea what a good mill cost and I was very surprised to see some of the prices. I need to rethink my plans and buy something that will not only do the things I'm thinking of today but can grow with me for the next 2-3 years doing things I haven't imagined yet. In the long run it will save time and money buying the biggest mill I can afford right now.

                Comment


                • #9
                  Originally posted by amarillo_rocket
                  I'm having trouble figuring out what is the next step above these mini mills without purchasing some 300lb or more behemoth that I don't have the space for right now. Any suggestions?
                  welcome aboard! i'll echo what others mentioned about Grizzly. they seem to be a bit better quality than Harbor Freight (i've bought things from both).

                  as for your "300lb behemoth" comment, i have to laugh. i probably have 300lb of junk just laying on one end of the table on one of my milling machines. search out some cheap, old iron that weighs about 10x 300lbs and you'll be glad you did (if you have room for it of course). you would be surprised how small of a corner you can jam 3000lb of milling machine into.

                  andy b.
                  The danger is not that computers will come to think like men - but that men will come to think like computers. - some guy on another forum not dedicated to machining

                  Comment


                  • #10
                    It's my understanding those mini-mills have plastic gears.They are not likely to have the durability required for a business,no matter how small.
                    As has been noted,get the biggest you can afford/have space for.
                    Another point to consider is the column.If at all possible,get the dovetail type,as the round columns are a pain to line up after moving the head up/down.You don't want to be doing that 40 times a day.Then there's a choice of belt drive,or gear drive
                    I have a ZAY45 gear drive taiwanese model,and it does everything i require.A power feed on the table is nice,but you can make your own with a windscreen wiper motor and a simple speed control.
                    Visit some dealers if you can,and have a play with the machines on the floor.It's surprising how different individual models"feel".And be careful what you wish for.once you have to do machining (or any hobby,for that matter)to make a living,it's very possible it suddenly ceases to be fun.
                    Hans

                    Comment


                    • #11
                      yep 300 lbs is nothing - my little import job is 490 lbs and cutting a 1/4" by 1/2" deep slot is a big deal. A big, time consuming deal. Not to mention if you try to take to heavy a pass with a round column mill the head can pivot and screw up your work piece. This is not an issue (or not as big of an issue) with large round column mills because they have a larger column and you can lock them down better. Some of these imports have a 3 or 4" diameter column and you can clamp down on the lever to lock it just as hard as you like (i actually broke one lever) and it will still move if you try to take a heavy cut.

                      Just something to keep in mind. Like others have said, on my little mill it would take 3 to 4 passes depth wise to get to 1/2" - 3 on aluminum and 4 on steel. On the other hand, the bridgeport at the university here will take a 1-2 passes to get to that depth and end up with a slot that is just as accurate as my little mill can do in 4 times as many passes!

                      Comment


                      • #12
                        Originally posted by Rif
                        Think of it this way: The amount of time to mill a slot is inversely proportional to the size of the mill. In other words, a small mill will work, it will just take longer. Since you are talking about a business, time is money.

                        Brian
                        You REALLY need to pay attention to what Brian said above.
                        I'm thinking you are maybe sorta like me...a mad scientist inventor wannabe.
                        I'm now up to my armpits in business for myself. Most of my machines are too small or too slow now. Even if you are just doing R+D for things you've dreamt up...after awhile the glamour of milling a 1/2" deep by 1/4" wide slot will wear thin on a small machine.
                        These "business ideas" we have...great to start out with a file and a hacksaw but as soon as it looks like it may work you'll be kickin your butt because everything is taking far too long.
                        I wouldn't start anything like that with anything less than a 2 hp mill/drill...about 800 pounds but still a pretty small machine. And for sure it'd have powerfeed on the X axis....and I'd really hate to have to run a mill without a DRO again. But that's just me.
                        Russ
                        I have tools I don't even know I own...

                        Comment


                        • #13
                          Mill

                          If you have a project needing many holes and slots you need to consider punching the material. Rounding the edges is better suited to a mill unless the materialis aluminum and then a router can do the job.

                          JRW

                          Comment


                          • #14
                            Mill Selection

                            Originally posted by amarillo_rocket
                            I see everyone's point and I appreciate the advice. I have a few other hobbies and I learned from them that cheap tools take twice as long to use and usually don't do a good a job. I guess I need to use my own experience as a lesson. I think the problem is I had no idea what a good mill cost and I was very surprised to see some of the prices. I need to rethink my plans and buy something that will not only do the things I'm thinking of today but can grow with me for the next 2-3 years doing things I haven't imagined yet. In the long run it will save time and money buying the biggest mill I can afford right now.
                            I think the best advise to take is your own. I was in the same situation about 5 years ago, asking the same questions. I did the looking for the used mill and after being disappointed so many time after traveling many miles to look at a mill in "fine running condition" only to find a rusting hulk, I finally ended getting a new Grizzly mill. (Current Model G9902) It has done EVERYTHING I have tried to do with it and have not been disappointed with my choice. You will be surprised at how how fast projects grow when the capability to do them is there.

                            Bill
                            Bill

                            Being ROAD KILL on the Information Super Highway and Electronically Challenged really SUCKS!!

                            Every problem can be solved through the proper application of explosives, duct tape, teflon, WD-40, or any combo of the aforementioned items.

                            Comment


                            • #15
                              This little K&T mill should be able to do what you need done! I saw one of these sell for $450.00 at a local auction last month.

                              http://cgi.govliquidation.com/auctio...tionId=1462779

                              Comment

                              Working...
                              X