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  1. #11
    But the look of it, is not the setup that I will use. I will for my X axis, only have one rail pr. side and not two.
    Yes it is, just rotate the diagram 90deg. in your case the distance between the rails will be greater but the load distribution will be the same. for the x axis you need to allow for all the weight of the y and z axis so a greater capacity in the vertical is better, ie the first diagram. As you want to mount them on their side then diagram 2 will apply so you will have reduced load capacity and therfore require more pillow blocks to get the same effect.

    So if the initial design required 2 blocks per rail then to get the same strength when mounted on the side you will need 3 blocks per rail.

  2. #12
    Ok, I see then. However, I think I have overcome the problem, by mounting an heavy angle iron on the side, and mounting the rails on top of these.

  3. #13
    Ok, I see then. However, I think I have overcome the problem, by mounting an heavy angle iron on the side, and mounting the rails on top of these.
    That may still cause problems if the angle can flex......How big is your machine and what are you cutting?

  4. #14
    my machine is 4'x8' so it's going to be quite big.
    the angle iron will be run at the machines full length if used that way.
    mainly cutting wood materials, Nylon sheets, plexi and so on. Not cutting metals.

  5. #15
    Quote Originally Posted by Gary View Post
    While it can be done, dont expect to put the rated load though the bearing.
    The bearing is open and the case is ally so will bend if too much load is applied, and when this happens it will go all sloppy.
    But isn't that the same wether you mount on the X, Y or Z. Somthing to do with load planes being the same ?
    .Me

  6. The supported round rail is designed so the load is directly on top.
    I have seen it used in different orientations, but it is not designed for that.
    As an example the TBR16 has a max dynamic load of just under 40 KG, but if you mount it on its side this will go right down and would definitely fail with sustained load of 40KG.

  7. #17
    Am I missing the point here, but that is per bearing? As most x and y axis will have 4, and even with a 70% reduction, thats still 112kg. Add another bearing per side and that goes up to 168kg. thats quite alot no?

  8. #18
    The load planes are in the same direction wether you mount the rail laying down or tip it on its end are they not ?
    .Me

  9. #19
    The load planes are in the same direction wether you mount the rail laying down or tip it on its end are they not ?
    What do you mean by load "planes"? are you refering to the loads/forces placed on the bearing or resistive load capabilities of the bearing?

    If the rail is mounted vertical then it is not technicaly subject to gravitational forces(because the bearing moves in this direction) so it only has to deal with cutting forces. X and y have to take the weight of the machine as well so loads are not the same in all planes.

    As the bearings are open on one side then this area has reduced capacity by about 50% (so depending on the mounting orientation this will be different for each axis/plane) which is why I believe that they should be mounted back to back to even it out.

  10. The rail is designed as a supported type, but you put it on its side and it is not supported as well anymore and you could bend the rail if the weight is too high.

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