Re: Disaster when changing the poly v belt
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Re: Disaster when changing the poly v belt
Even I have had this problem occur to me when repairing and rebuilding headstocks. Getting too quick to see the results with out checking everything has been tighten and in place. I find this type of problem has occurred often over the years when the Idler Shaft starts to slip from the headstock casing and starts destroying the Gilmer or Poly-V belt. It also can destroy the motor belt at the same time. I developed a Mark V Headstock Improvement/Rebuilding Kit with new parts including the 3/4" body washer and star washer to hold the Idler shaft in the "B" & "C" headstocks. I also replaced the cone point set screw in the eccentric bushing with a knurl cup point set screw to better hold the Idler Bearing in the eccentric bushing. The kit includes a bolt, star washers and nylock nut to replace the roll pin in the speed control assembly along with a new bolt, lock washer and square nut to hold the eccentric bushing.
Re: Re: Disaster when changing the poly v belt
Bill, I just did your advised replacement of the point set screw in the eccentric bushing with a knurled one a few days ago. Something you didn't explain in your reply above but did in the post that inspired me to do it is that it accomplishes two things: it let's you have more range to adjust where the shaft is (in the direction towards or away from the quill, parallel to the length of the shaft), which I needed to get my gilmer belt right, and it reduces the risk of deforming the bushing from the concentrated pressure of the point set screw.
Rdewinter, a few thoughts... First is not to worry that you will turn it into an anchor. You'd have to work very hard indeed to destroy one. I've now managed to take my two old Mk V's completely apart with the exceptions of the motor itself (so far) and pulling the bearings from inside the quill. I did all of it by getting guidance here, and if I can, you can too. Chances are you've done more such work than I.
Second is to take Bill's advice above. Replace the roll pin holding the pork chop on with the bolt, washer and nut set from Bill. In my case that and a little persuasion was all it took to get the bent and misaligned chop back in place and remove excess play. It no longer binds up at all.
Sounds like you've been here longer than I have so I don't mean to be impetuous, just encourage you to go ahead and tackle it yourself as others suggested. You can always send it off later if need be. But chances are you won't.
Rdewinter, a few thoughts... First is not to worry that you will turn it into an anchor. You'd have to work very hard indeed to destroy one. I've now managed to take my two old Mk V's completely apart with the exceptions of the motor itself (so far) and pulling the bearings from inside the quill. I did all of it by getting guidance here, and if I can, you can too. Chances are you've done more such work than I.
Second is to take Bill's advice above. Replace the roll pin holding the pork chop on with the bolt, washer and nut set from Bill. In my case that and a little persuasion was all it took to get the bent and misaligned chop back in place and remove excess play. It no longer binds up at all.
Sounds like you've been here longer than I have so I don't mean to be impetuous, just encourage you to go ahead and tackle it yourself as others suggested. You can always send it off later if need be. But chances are you won't.