Jakobsen 1032 surface grinder cross feed issue!
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  1. #1
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    Default Jakobsen 1032 surface grinder cross feed issue!

    Hi all,

    Iíve got a jakobsen 1032 automatic down surface grinder.

    It has a couple problems with the cross slide when in feed. When the table is closest to the column the table gets stuck after a certain point about 50mm from end of travel. Also when the table is closest to operator side the table jumps up or the head bumps down about 0.01mm. The problem can be overcome by limiting the table travel about 2 inches at both ends. But this isnít helpful when grinding wider parts.

    Has any one done much work on these grinders that is able to shed some light?

  2. #2
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    We need more information.

    What happens when you crank the crossfeed by using the handle? Is there more resistance to motion at either end of the table travel?

    Is the problem recent or has the grinder always had this problem while under your care?

    The information may identify a bent lead screw, a dirty lead screw, sticky ways,a jammed floating nut mechanism, or a incremental feed problem in the gear train of the cross feed.
    The hydraulic motor and fluid metering plumbing are less likely to be the problem.

    I do not have knowledge of the Jakobsen grinder however the mechanical design will likely have much in common with other surface grinders.

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    Hi, and the machines history is that it was crashed in its first week and was never truly repaired. (20 years ago) They crashed the wheel head dresser too but thatís a job for another time.


    The machine works by a lead screw and a hydraulic ram side by side there is a half nut by the leaver that engages the half nut when the hydraulics canít be used. But Iíve told that a Very talented toolmaker once broke the interlock that locked the hydraulics off while the lead screw was engaged and forced the hydraulics in which just mashed the insides.


    After another investigation I managed to push the table right back, un fasten the end bracket that links to the table and let the rod push out so I can see up itís used length.

    And itís pretty fatal. The chrome has rubbed off one side of the cylinder and is heavily scratched where itís been rubbing over time which I can only assume is caused by a bent rod. I measured the diameter a few places over and the wear at its worst is 0.05mm

    Iíve looked in the spare parts book and it gives a assembly of the cross slide cylinder which shows it having a two piece rod thatís screwed between the piston. I canít see the the other section unless I get the table and slide off. So I assuming thatís worn as-well because I have issues at both end of the travel.

    My end prognosis is that the bent rods are bent upwards originally which causes the table to rise at either end of travel causing the crowning of larger work pieces. Iím going to speak to the maintenance guy too see if he reckons any other guides or parts would be likely to be just as worn. Then Iíll see if Jakobsen will send me a quote for new parts and what they charge for a whole new cylinder too...

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    I was not expecting a direct hydraulic piston cross feed mechanism for the Jakobsen grinder.

    The connecting link between the piston rod and the table should have a sliding motion to prevent the table from lifting if there is a small bend or a small misalignment of the piston rod. If there is a large bend the connecting link would not have sufficient travel.

    Is it possible to remove the hydraulic piston, cap off the hydraulic lines, and do a test grind with just the cross feed lead screw? That would allow you to verify that the problem is limited to the hydraulic piston.

    The lead screw may also have been bent or the half nuts damaged in the pushing contest with the hydraulic cylinder.

    I suspect the repairs will be limited to the piston rods, piston seal, and the cylinder end cap seals, sleeve bearings and rod wipers.

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    On the connecting bracket it is just a solid connection that doesnít allow for any misalignment to find its own way out, and unfortunately I have to remove the cross feed handle to allow the rod to feed out when unconnected. But I like your idea and Iíll find a way around it.

    And that very much is the problem. I do fear that this forcing of the ram has put unnecessary compression strain along different points on the slide which would cause wear but Iím not 100% sure yet. Itís strange how the worn chrome is the length of the visible rod but I only get issues on the last two inches of travel at each end.

    When I do a job thatís 12 inches wide I can grind to 0.005mm across but if itís 14 inches wide I get a constant crown of 0.015mm that slopes at both ends.

    Plus all the lost time from the table forcing its way as it gets stuck at the end of travel. I think it has about 16inches total travel.

    I think the bottom line is to get a quote for the parts after a few more tests and to tell my boss whatís what and that to fix it itís a near total strip down.

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    Also the lead screw may be bent but as the half nut is disengaged Iím hoping that any problem with that wonít influnce anything so far.

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    Quote Originally Posted by Luke.kerbey View Post
    On the connecting bracket it is just a solid connection that doesnít allow for any misalignment to find its own way out, and unfortunately I have to remove the cross feed handle to allow the rod to feed out when unconnected..
    The hydraulic cross feed cylinder may be attached to the grinder base with springs or a hinge mechanism to allow some piston rod misalignment.

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    Yer I hoped thatíd be the case but wasnít, itís a rigid bracket that fastens to the machine base.

    I emailed Jakobsen for a quote and after a google translate, they came back with £300/£350 for the rear and front rods, or the whole cylinder assembly was £2250 plus VAT (20%).
    Itís in my mangers domain to now to organise the Fix now. Ive done all the leg work...

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    This is the image of said bent rod. Can anyone give a opinion on how long before the seals blow??


    Sent from my iPhone using Tapatalk

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    Could you remove the cylinder and rods and bring them to a shop that repairs/rebuilds hydraulic cylinders? Around here there are some small companies that do that kind of work. They are fast, competent, and the prices are significantly less than the parts costs you are being quoted.

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    Yes, we have a few of those right near us. It will probably be what we do when it blows the seals, my manager has already turned round and said heís not gonna fix it....

    Iím not gonna completely rip in to my manager as he canít defend him self here, nor is it professional to do so, but Iím not sure what he is going to achieve by not repairing it in our down time. According to Sodís law itís only ever going to catastrophically breakdown when we need it most...

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    Don't know where you are with this repair at the moment. I have used a firm in Luton who specialise in rechroming and grinding hydraulic rams and motorcycle fork staunchions. They tell me EVERY ONE has some bend in it when they get them in for repair. They charge around £150 for a pair of fork legs, to strip off the original hard chrome, straighten, rechrome and regrind

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    Hi, basically I presented the problem to the manager and what he needed to do to fix it and he says there is no money to fix anything. He also says he has a Toolroom budget but doesnít know what it is! Rant aside, itís dead in the water and Iím waiting for the day it spews hot oil everywhere, which will almost certainly coincide with when we have a stack of plates to grind!

    But thanks for the recommendation, we arenít too far from Luton!


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