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Opinion on a used mill

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  • Opinion on a used mill

    Hey gang,

    I found a mill. Not far from me and maybe a good price. It is an older (20 yrs old) bridgeport Series II milling machine. 4 Hp and power everything. I will most likely go and see it on Wednesday. Any advice of what i should look at?

    Second, the delivery of it has me concerned. It seems a tilt and Load will be the best way. When they lower it, what should i watch for, rather how can i make sure it does not fall over?

    Rob

  • #2
    Originally posted by spkrman15
    how can i make sure it does not fall over?

    Rob
    Use sling and lift of course

    Comment


    • #3
      I think I read somewhere that the Series II BP's were something a good bit over 4k pounds, so that one's going to be some work to move, as well as requiring a correctly rated trailer.

      Edit-- I just re-read that you are going to try a tilt bed wrecker if I understand correctly. Mills are inherently tippy. The base of the Bridgeport knee mills is narrow in one direction, making this even worse. I would try to find a way to lift it on and off if possible rather than sliding it on and off a steep ramp like you have with one of those tilt-beds. I first thought you were talking about a drop-bed trailer, which may be a better idea.

      I know with the series 1's the standard move stance is to drop the knee all the way down, run the table to the far rearward position and carefully rotate the head completely upside down and bring the knee back up to just touch the top of the motor housing. The head inversion is a two-man job really as its designed to tilt with the worm gear adjustment up to a point....beyond that, it takes someone to help resist the weight of the head in order to be able to rotate it as the other guy rotates the worm gear adjustment...and you have to pull a pin to allow it to rotate that far--a safety feature.

      How this relates to a series II, I don't really know...hopefully someone else will respond with their experience.

      Paul
      Last edited by pcarpenter; 05-24-2008, 11:37 PM.
      Paul Carpenter
      Mapleton, IL

      Comment


      • #4
        Well the guys said they have a 6000 lbs forklift and it was all they could do to lift it. I don't have that kind of machinery and around here, and a crane is a 4 hour minimum. 150.00 an hour. I am pretty sure my brother in law's backhoe won't lift it either. I might have to rent a fork lift! ugh MORE MONEY! haha.

        The tilt and load does seem kind of tricky. I wanted to know if anyone has used that method?

        Rob

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        • #5
          I have a Supermax clone of a BP Series II and its around 3k. The BP should be about the same. You could always call Hardinge and get a weight.

          I would rent a drop deck trailer.

          Comment


          • #6
            sliding a mill off a trailer

            Having done this successfully with 3/4 ton mill I would strongly suggest caution but it is possible at least with smaller mills. I won't tell you how you should do it or advise you how (disclaimers etc..) - This is how I did it for my mill.

            The trailer was low bed type with metal ramps normally used for small 1-2ton diggers so I knew that the ramps and the steadies were up to it.

            The mill was resting on two short lengths of square section steel in the centre of the trailer and I had another two identical short lengths to use as skids.

            The configuration of the mill meant it must slid down the ramps with its 17" wide base providing little stability to the top heavy mill.

            We start - along the trailer
            After removing the ties I secured a wire rope on a 500Kg Tirfor winch from the front of the trailer to the top of the column. We then tilted the trailer as much as we could and set the rear steadies down firmly and put the ramp down.

            We then levered the mill down the trailer putting down the sq section steel skids in front as it was released from behind. We did this using some more Sq section steel as levers while letting out the wire rope on the Tirfor.

            The ramp! - here things got interesting and we should have had a second tirfor on the base to keep things even steadier. Even so the mill slowly moved down the ramp as we let the wire rope slacken with occasional
            encourage ment from the levers. It moved a little jerkily - which increased the heart rate somewhat and it needed squaring up on the skids as it moved down the ramp.

            The bottom of the ramp
            At the bottom of the ramp we placed skids on the ground. The mill progressed as before and then stopped!
            The mill would not move along the skids on the ground beyond the ramp. It was digging in to them - it was stuck! The mill was also on its point of tipping but was held there by the wire rope on the column.
            The solution
            We got out of this by slowly moving the trailer away from the mill (It stayed where it was) and slackening the wire rope as we did so,the wre rope ensuring the mill did not go beyond the tipping point. As the trailer moved away the mill came upright and on to the skids on the ground.
            We then used the levers and skids to manouvere the mill.

            Lessons learned - Three persons, two tirfors and six skids would have made things easier

            Comment


            • #7
              Wow!

              Ok that things is huge! 9' high, it has a riser block. It will stick out 6' from the wall. It has motors that power everything. Quill, Y, X and Z. The guy figures it weight about 5000lbs. WOW! Too much machine for me!

              Rob

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              • #8
                I just bought a series 2 CNC, manual lists the ship weight at 6200 Lbs, uncrated weight at 5800 Lbs. We had to dissassemble the thing to move it with my buddies big loader. Broke one 10K strap on it, had to resort to 3/8" chain. The loader is a big 4wd Case, we couldn't even budge it with the head on, after we pulled that, we could lift it off the ground, but it damn near rolled the loader. Pulled all of the controls and cabinets off it and then could move it fairly easy. It was a challenge to put it back together in the shop with no room to get the loader inside. Did it with car skates to move the base, engine hoist to install the head, and pipe rollers for final positioning. It was not fun. We figured a few hours to grab it, and put it in place. It took the better part of 12 hours just to get it into my shop, not even together.

                Hell of a machine though Well worth it. Footprint is 7'x8'. If it is cheap, like mine was, I would try as hard as you can to swing it!

                Later,
                Jason

                Comment


                • #9
                  When I moved my mill home I had a wrecker come out and pick it off the trailer and put it on skids in the shop I then rented a pallet jack to move it into place and left it on skids. My mill is a Wells Index and weighs around 3000#.
                  Mike

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                  • #10
                    WEll the big problem is how far it sticks out from the wall. I only have a 20 x 24' garage. Losing 6-7' on one side is not something i am fond of. I do the occasional automotive repairs, welding, etc and need the area.

                    The motor is a 4hp, i can only get a 3hp VFD. There are also tons of controls at the back for the X, Y, and Z motors. I guess that makes it one step closer to converting it to CNC?

                    I have mixed feelings as it was outside when i got there under a tarp. I can't see it run. I have learnt that sometimes it is better to go over your budget and get what you want then try and save a few $$. That usually ends up costing you in the long run

                    Rob

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                    • #11
                      Knee mills, even big ones, fit perfectly into a corner. Aim the back of the ram at the vertex of the corner and pull the mill out so that the table clears each wall at the extent of travel.

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                      • #12
                        it is quite easy these days to buy a bigger (much bigger) vfd than 3 hp they are not too expensive these days.However don't automatically assume that it will run on a vfd.And unless you can be sure watch what your doing.I have two 5 hp invertors a 7.5 hp static convertor and a 5.5 hp rotary convertor and my lathe would only work on the rotary nothing else would do. Kindest regards and have fun with whatever you decide to buy be careful kinddest regardsAlistair excuse typing
                        Please excuse my typing as I have a form of parkinsons disease

                        Comment


                        • #13
                          Vfd

                          I have a 7.5 hp teco MA7200 VFD running my 5hp lathe motor off of single phase. There have been many discussions on sizing, the general consensus seems to be derate to 2/3 if running off of single phase input (7.5hp * 2/3 = 5hp). Some VFD's have a missing input phase detector, my 7200 doesn't.

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