Custom Table - Motor Placement Relative To Machine Puley

[yoji]

Hi All

Due to limited cylinder arm table availability here, i need to make my own table. by recycling some of the materials from the old one.

In order to make the most out of my working space i would like to use a bit narrower table.

So my question is, does the V-belt which goes from the motor pulley to the machine pulley must be angled like around 45 degrees?

Or is it OK to place the motor pulley directly under the machine pulley (180 degrees)?

It is for adler 69 cylinder arm. My logic tells me that it should not cause any loss in torque, but i am not the experienced one here, nor an engineer.

Also i am going to use a somewhat strong and dense 25- 30mm MDF and 3mm steel plate underneath for some extra durability.. Is it too much? I am using a servo motor which is around 13lbs, and the adler around 62lbs. (i will be placing a leg just under the machine to remove some of the stress and distribute weight better in order not to stress the wood too much. does the plate is an overkill?

Thanks.

Edited July 4, 2014 by yoji

[VanRhodes]

No, it must not be around 45 degrees. I believe one the main reason for this placement on commercial tables is because it allows you to tilt the machine head backwards and easily slip the belt of for replacement. I have seen tables using a very long V-belt where the axis of the motor was perpendicular to the axis of the drive shaft in the sewing machine as well, so placement seems to be very free in that sense.

[Constabulary]

Technically you can place the motor where you want and 180° is fine. A lot of machines having it this way, especially treadle powered machines. But check if the connection between motor lever and pedal (pitman rod or chain) will work in this position. You know what I mean?

s it a full plate or has it a cut out? 30mm MDF is fine I´d say. I have seen much heavier machines on 25mm tables. No need for a steel plate. Instead of a steel plate I´d choose a thicker wooden plate (40mm - 45mm) but I think 30mm is fine.

[Constabulary]

BTW - if you want the table in a fixed position like a shelf why not using heavy duty shelf brackets so you can put one directly under the machine for supporting it.

[yoji]

Thanks for the replies!

I have just finished the table and installed the motor. so we will see how it will work once i will get the new shorter V-belt .

@Constabulary: I need to move the table from time to time so thats why i cant use a shelf.

My motor uses pitman rod, i will need to hack it though for a better placement. I just had to hack the knee lift since i had to rotate it 90 degrees and place it in a different position and not directly underneath the pull chain that was coming from the machine.

I had some bicycle gear shifter cables (stainless steel with teflon coat and used some hooks to guide the cable. And it works suprisingly well.

I guess i will come up with something like this for the motor lever-pedal.

Will post some pics once it is completed, maybe it can help someone out there.

Thanks!!!