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Re: V-belt replacement

Posted: Wed Mar 06, 2019 9:05 pm
by reible
You have an older headstock then I'm use to but I'm guessing there are a few things I would look at starting with the mounting of the motor. Perhaps it is time to drop the pan and motor and see if anything looks out of place. Maybe something bent or holes enlarged, screws loose, anything at all that would cause it to be that misaligned.

I'd go to the guy on ebay, heard only good things about his job.

Ed

Re: V-belt replacement

Posted: Thu Mar 07, 2019 2:39 am
by JPG
I think the motor pan is bent out of shape and the major cause.I no longer think that

I also think the belt is contributing to the propensity to rub(non oem-slightly wider-slightly longer).

A new(used) motor pan may correct.Not needed

Re: V-belt replacement

Posted: Thu Mar 07, 2019 4:03 am
by dusty
Looking at the very last image posted leads me to say the motor is not properly oriented in the motor pan. I'd "loosen" the four screws that secure the motor in the pan the then check to see if you can move the motor around so as to achieve alignment of the shafts.

Good luck. Hope you can avoid buying parts. :( Save that money for tools. :)

Just to give you a different perspective:
Shaft and Tube Relationships CORRECTED COPY no reference lines.png
Shaft and Tube Relationships CORRECTED COPY no reference lines.png (50.87 KiB) Viewed 11061 times
Nothing is specifically identified. Prepared for my own needs. You will have to use your imagination.

The dashed lines forming a triangle mark the path that the belt would be on.

Re: V-belt replacement

Posted: Thu Mar 07, 2019 8:36 am
by wa2crk
The pictures with the plumb line tell all. It is possible that the end bells of the motor were installed improperly by a previous owner. Check the motor mounts to make sure that the correct ones are used and that the motor "feet" are properly orientated.
Bill V

Re: V-belt replacement

Posted: Thu Mar 07, 2019 12:08 pm
by roneg
Thanks all for your input. Thinking back.. The person I bought this machine from 2 years ago mentioned that his Dad did, or had done, a Motor rebuilt in the past. So yea, anything is possible here. I have noticed the motor plug and wire is not original. It is longer and of a flat type, with no grommet, at the pan entry point. Looks like a motor removal is in my future. :rolleyes:
wa2crk wrote:The pictures with the plumb line tell all. It is possible that the end bells of the motor were installed improperly by a previous owner. Check the motor mounts to make sure that the correct ones are used and that the motor "feet" are properly orientated.
Bill V
By end bells, I suppose you mean the metal ends at each end of the motor housing? The one shown in the last two pictures.

Re: V-belt replacement

Posted: Thu Mar 14, 2019 2:49 pm
by roneg
Dis-mounted the motor, and assy. The pan does not appear bent (the belt cover fits snug all the way around), the motor mounts seem to me normal. Don't know the normal distance between the waytube, and belt (not in any diagram I've seen). I'm thinking of installing a couple of split washers between the pan, and motor mounts to "wedge" it over the direction it needs to go, then screwing in down with new longer screws. Good idea?

Couple of things I noticed, with the parts exposed upon motor removal. The switch wires have been coming in contact with some moving object (rubed through insulation)..I'm guessing Main belt. Is there some diagram, or routing..wire clip, or suggestions? Also since there is no color coding on my motor wires, and none on the pig tail what is the proper way to wire the (new switch), to motor? I will be installing a new/used pigtail with quick dis-connect connectors Blk, Wht, Grn also.

Thanks,
Ron

Re: V-belt replacement

Posted: Thu Mar 14, 2019 4:22 pm
by dusty
That being the case, I'd like to hear about what you see if you rehang that plumb bob. What are the dimensions from the string to the tubes. Whatever the distance is should be the same. That is, the plumb bob should hang straight down the center line.
Shaft and Tube Relationship with Plumb Bob.png
Shaft and Tube Relationship with Plumb Bob.png (37.61 KiB) Viewed 10909 times

Re: V-belt replacement

Posted: Thu Mar 14, 2019 6:35 pm
by JPG
I would be interested in a pix of the bottom of the motor pan showing the motor mounting screws.

BTW I recommend adjusting the eccentric the other direction to tighten the poly-v belt.(from 6 to 9 rather than 6 to 3)

Re: V-belt replacement

Posted: Thu Mar 14, 2019 9:16 pm
by JPG
Never mind!

I tore into my vintage specific(sorta*) "A" headstock and found the following.

The motor IS off set towards the operator side by about 5/16"(a straight edge laid against the operator side of the main and idler shafts intersects the center of the motor shaft).

The v belt is riding slightly above the outer rim of the motor pulley at "fast".

The belt clears the way tube by about 1/4".

*The main and idler shaft are poly-v.

*However the motor has been spaced up off the motor pan by 1/4" to allow using a stock 26" belt. I do not think that affects the other details significantly although it may decrease the offset(standard belt would be further off set very slightly).

Does not explain a belt rubbing the tube, but does clear up the offset is 'normal'.

Re: V-belt replacement

Posted: Thu Mar 14, 2019 9:36 pm
by roneg
Very interesting JPG. So it would appear the mis aleighnment is normal. However I'm confused how the belt can help but rub when running at high position on the motor sheve.