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  • Is bigger better?

    My company is giving me bonus, not sure for what but who am I to question their decision?

    Anyway, I figured i could get Semi - Universal Dividing Head for my Grizzly 728 milling machine.

    Now the question. Should I go with BS-0 (smaller and cheaper) or BS-1.

    BS-1:

    http://www.ebay.com/itm/BS-1-Semi-Un.../162104259253?

    hash=item25be2ab2b5:g:M3YAAOSw3v5XInFc

    BS-0:
    http://www.ebay.com/itm/BS-0-Dividin...MAAOSw3v5XInCj

    Is the higher capacity worth the $100+ difference?

  • #2
    It all depends on what you will be using it for.
    They are probable most often used for cutter gears. What size gear do you think you would want to make, will it fit the smaller one?
    If it's very seldom you would need the larger size you could put raiser blocks under the small one for those few times and save $100 or more likely spend it on some other tooling.

    Comment


    • #3
      For the size of mill we share I think either would be a superb addition. The table on this mill will easily accept either head and there's enough Z axis to take either option and still provide for good work clearance.

      For smaller items or lighter cuts on larger items I suspect the smaller head will be rigid enough to work well. But if time is money then the bigger and heavier head will hold against the pressure of serious cutting with less flex and thus more consistency. But if you're willing to live with the need for lighter cuts on bigger items then I don't see why the already fairly good sized BS0 would not be just fine.

      I think I would be swayed more by the idea of the 6 inch chuck over the 5 inch. But then both have the same spindle and nose thread so perhaps it's not a big deal.

      I want to ask "how much will you use it?" but that can become a self fullfilling prophecy. If you opt for the smaller based on the idea you won't use it all that much it may be a trifle too small for the jobs you would LIKE to use it for. So some self questioning on what sort of projects you make is in order.

      Do you already have a rotary table? And do you really NEED the angular ability of the dividing head? Sector plates, arm and tail stock kits are available as accessory kits for horizontal/vertical rotary tables. What you lose with a rotary table as an indexing head is the tilt angle ability.

      I know that I've used my rotary table both in the vertical position for indexing as well as flat as a rotary table. To date I've never used the sector plates for serious indexing. But I've used the tail stock often when doing vertical table indexing. And SO FAR I've never missed the ability to set the axis on a tilt angle.

      Comment


      • #4
        Thank you for the input, guys. As of now, I only have a swivel vise to angle anything on the mill table. This would be an overkill to cover my needs for the rest of my life

        How much I will use it? Hard to say, the other day I could have used dividing head - I would make a chain sprocket if I had one.

        I build implements for my tractor, custom parts for my old Honda motorcycles and fix stuff that needs fixing - or whatever my wife tells me to do
        Last edited by Prokop; 06-16-2016, 04:32 PM.

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        • #5
          I would ask the weight. I seem to recall going with a 8" rotary table because the 10" seemed way too heavy to wanna lift on/off the mill by myself.

          I can only assume a universal dividing head with the extra swivel feature weighs even more.
          Play Brutal Nature, Black Moons free to play highly realistic voxel sandbox game.

          Comment


          • #6
            "I would ask the weight."

            A good question. All tables have a rated capacity. Getting past 50% of that can make moves difficult, worse with cantilever.
            No biggie for small workbits with a centered R/T or DH.

            Comment


            • #7
              Those dividing heads aren't that heavy. Quite a bit less than a rotary table. To me, the main thing you gain over a rotary table is access to the part near the end. A rotary table with a 4 or 5 inch edge to center distance can make for some long tooling. With the dividing head you can run on centers with a lathe dog and not need any extensions, plus the angular option. I once made a lot of broaches that way, by angling the DH to make the taper.

              Comment


              • #8
                Your work.
                Your mill.
                Your money.

                I would get the larger one, but that's me.
                Paul A.

                Make it fit.
                You can't win and there is a penalty for trying!

                Comment


                • #9
                  I have a o BS works great it lite to set up on the mill
                  You find it you are in to weight lifting get the 1 bs works wonder on your back too.
                  You will find just use raising blocks on the 0 bs will work fine and a lot liter too.

                  Dave


                  Originally posted by Prokop View Post
                  My company is giving me bonus, not sure for what but who am I to question their decision?

                  Anyway, I figured i could get Semi - Universal Dividing Head for my Grizzly 728 milling machine.

                  Now the question. Should I go with BS-0 (smaller and cheaper) or BS-1.

                  BS-1:

                  http://www.ebay.com/itm/BS-1-Semi-Un.../162104259253?

                  hash=item25be2ab2b5:g:M3YAAOSw3v5XInFc

                  BS-0:
                  http://www.ebay.com/itm/BS-0-Dividin...MAAOSw3v5XInCj

                  Is the higher capacity worth the $100+ difference?

                  Comment


                  • #10
                    ...You will find just use raising blocks on the 0 bs will work fine and a lot liter too...
                    ...For the size of mill we share I think either would be a superb addition. The table on this mill will easily accept either head and there's enough Z axis to take either option and still provide for good work clearance...
                    Well, a lot of that z-axis space gets eaten up very quickly. I have asked exactly that question on this forum for exactly that reason, and was informed that a BS-0 in vertical position is 220 mm or 8.7" tall with a 3-jaw chuck on it. Grizzly says that the mill has roughly 13" of Z travel. I don't know, but there might not be much space left. I don't know how tall a BS-1 is.

                    ... And do you really NEED the angular ability of the dividing head?... SO FAR I've never missed the ability to set the axis on a tilt angle...
                    Idunno, man... the ability to tilt is a huge advantage in my mind. Absolutely necessary, in fact, but maybe that is just me.

                    .

                    Comment


                    • #11
                      I would not assume those dividing heads are really Brown & Sharpe taper. Many spec sheets are wrong. Many of the Chinese suppliers got smart and converted them over to Morse taper. You'll found out then you get it.

                      Comment


                      • #12
                        Originally posted by Dr. Rob View Post
                        Well, a lot of that z-axis space gets eaten up very quickly. I have asked exactly that question on this forum for exactly that reason, and was informed that a BS-0 in vertical position is 220 mm or 8.7" tall with a 3-jaw chuck on it. Grizzly says that the mill has roughly 13" of Z travel. I don't know, but there might not be much space left. I don't know how tall a BS-1 is.



                        Idunno, man... the ability to tilt is a huge advantage in my mind. Absolutely necessary, in fact, but maybe that is just me.

                        .
                        You have a point there, I printed grizzly pdf for BS - 0 and 1 and will check the mill and space. Thanks!

                        Comment


                        • #13
                          In my earlier reply I asked at the end of my post if you had a rotary table already. If you don't I'd opt for a rotary table over a dividing head. My rotary table has come in VERY handy and been used in a reasonably regular basis. And as mentioned we don't have a whole lot of room between the spindle and table to work with on these mills. When rotated to the vertical position the dividing head not only take up a good amount of room but it also will be less rigid overall than a RT. The platten on the RT rests on the base all around the rim for great support where the dividing head equipped with a suitable lathe style face plate only has that center threaded stub to provide all the support.

                          Then I read that you make parts for your tractors (Now THERE'S a hobby ! ! ! ). Seems to me that the size of parts for a tractor would sort of suggest that more support for the work pieces is going to be a good thing.

                          So all around for me I see the RT would be the accessory that comes first and perhaps then the dividing head.

                          As for the angle cutting ability it might be a good project to make up a hinged angle plate as a project that is sized such that the RT you have or buy can be set to the angles you require. Or perhaps something like an over sized sine plate that can take the RT and be clamped to the table? This would both retain the working height and at the same time give us that angle cutting ability.

                          I'm liking the idea of the oversize sine plate for my 6 inch RT that can also be used for other setups. Like you I don't have a really good way of holding work at an angle. I've got one of those really cheezy drill press vises with the angle setting saddle in the base. It's a slight upgrade from the drill press vises that use the side plates and locking bolts but not by a whole lot. I sense a new project being added to the list.

                          Comment


                          • #14
                            Thank you, BCRider for the time and thought out answer. I will consider RT table as the first step, it makes sense.

                            Comment


                            • #15
                              I posted all of that before I knew if you had one or not.

                              I also assumed that your tractor hobby was on full size "U-Ride" tractors and not smaller size models. Is it?

                              For our size of mill the 6 inch rotary table is really the best size match. It will obviously take an 8 inch table but only with about 2 inches of overhang front and back or a LOT of overhang if you mount it with more off the front than the back. Even the 6 inch table has about 1/2 to 3/4 inch of overhang as it is because the base casting is that much bigger than the table.

                              Also when used vertically our two T slots don't mate up with the mounting slots in the vertical side of the casting. I'm still not sure what I'm going to do about that just yet but the one time I've used the RT on my new mill was in the vertical mode and I bolted one side down and used a finger clamp on the other. Not the best option but it made do for that case.

                              My old smaller mill drill had the T slots more widely spaced with three instead of just the two slots like we have on our current mills. So that was a bit of a "downgrade" for me and makes mounting the RT in the vertical setup difficult. And the 8 inch table would be even worse.

                              But then the 8 inch is sort of what you would prefer for doing any larger tractor parts. So it's a nasty decision.

                              The other downside to an RT over a dividing head is that when the sector plates are fitted for accurate indexing the plates and arm stick up past the surface of the table. And larger parts clamped directly to the table will not be possible without some sort of riser plate to obtain clearance. That's one point in the dividing head's favor.

                              So each has its pros and cons. I know for what I've done that I'm happy I got my RT first. But that's for me. And I'm not you. So I can only toss out what I've found and you can use what seems to fit your needs the best.

                              Of course in the end the proper answer is "one of each please" And if the bonus isn't that fat or some of it has to go to more mundane uses like house stuff then it's an iron clad cinch that whichever one you buy is going to be the wrong one for the very first job you need a rotary function for....
                              Last edited by BCRider; 06-20-2016, 03:59 PM.

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