My issue began with a n attempt at High Speed Adjust (coupled with an observation of how the various sheaves are positioned with respect to one another).
At both high and low speeds my measured rpm are about 700 rpm high (1397rpm and 8472rpm). I have put that aside for now.
Based on some info regarding the non-adjustable sheaves (fan sheave and idler sheave) provided by JPG a day or two ago, I have contemplating all of this and I now have doubts about my assembly. I need to know how the three shafts are positioned with respect to one another. I think this disgram shows what information I am attempting to validate (4 measurements).
Sheaves and Shaft at Mid Range Speed.jpg (64.25 KiB) Viewed 829 times
I have spare parts that can be used to confirm all other relative measurements. I doubt these four because there are inconsistency on my two machines
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
The 4 3/4" and 7 1/4" distances will vary inversely due to the rotational position of the eccentric. If your numbers above are accurate, the sum should always total 12" regardless of eccentric positioning.
The other two dimensions are suspect since what I stated earlier cannot occur and it IS necessary for correct speed range limits.
I cannot say for sure that the motor shaft has/is consistent through the past 7 decades.
I question the 9/16" since the idler poly-v pulley is too far out(idler poly-v pulley not centered on the drive sleeve poly-v pulley).
Would be a good idea to verify my 1" open recollection.
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
JPG wrote: Sun Aug 15, 2021 11:52 am
The 4 3/4" and 7 1/4" distances will vary inversely due to the rotational position of the eccentric. If your numbers above are accurate, the sum should always total 12" regardless of eccentric positioning.
The other two dimensions are suspect since what I stated earlier cannot occur and it IS necessary for correct speed range limits.
I cannot say for sure that the motor shaft has/is consistent through the past 7 decades. The location of the motor shaft is somewhat relative simply because it positions the Fan Sheave in a fixed location location. Its position, along with that of the Idler Sheave
The location of the poly-v pulley is also somewhat mandated. If it is installed properly (and I believe I have verified that) that shaft is firmly positioned. The poly-v belt is riding in the recommended grooves.The assembly is hard against a retaining ring in the casting. Yes, the idler shaft position is variable vertical and that has some effect (minor) on belt length but not on rotational speed.
The 1" measurement is close but not dead on.
I question the 9/16" since the idler poly-v pulley is too far out(idler poly-v pulley not centered on the drive sleeve poly-v pulley).
Would be a good idea to verify my 1" open recollection.
All of this is why I am attempting to validate the relative location of the three shafts.
Another very strong indicator that something is amiss is the fact that the v belt is not vertical (at any speed that I have checked). At the same time the machine seems to run as it always has.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
The location of the poly-v pulley is also somewhat mandated. If it is installed properly (and I believe I have verified that) that shaft is firmly positioned. The poly-v belt is riding in the recommended grooves.The assembly is hard against a retaining ring in the casting.
. . .
To be on the same page(?), I consider 'correct' to be centered on the drive sleeve pulley. Two empty grooves both in front and in back of the belt. i.e. 9 rib belt is centered on the 13 groove pulley.
With the relative positioning shown above, the motor belt cannot run perpendicular to both shafts.
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
I do not think the end of the motor shaft is a good place to measure.
The drive sleeve is positioned in the casting.
The idler shaft is positioned in the casting.
The motor feet are positioned in the motor pan.
The motor pan is positioned on the casting.
I think ALL measurement need to be relevant to the casting.
Problem is "where" on the casting for a common reference.
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╟JPG ╢
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Goldie(Bought New SN 377425)/4" jointer/6" beltsander/12" planer/stripsander/bandsaw/powerstation /Scroll saw/Jig saw /Craftsman 10" ras/Craftsman 6" thicknessplaner/ Dayton10"tablesaw(restoredfromneighborstrashpile)/ Mark VII restoration in 'progress'/ 10E[/size](SN E3779) restoration in progress, a 510 on the back burner and a growing pile of items to be eventually returned to useful life. - aka Red Grange
On a sample of one, I found the difference between shafts to be 11/16", you have this as 9/16". Both of my belts were very close to perpendicular to all shafts. This is on my shorty, a conventional headstock from around the turn of the millennium. I agree with JPG regarding motor shaft length, virtually positive that the very old, with the cap on the spring, are different than the relatively new with the washer because IIRC I have measured it.
Note: I went to a lot of trouble to get my belts perpendicular to shafts on my PowerPro. This, in comparison, was crude eyeballing. For the motor belt I used the HS casting holes with the belt cover pulled back. In the lower part of the speed range this provided a good visual reference line. At higher speeds the belt becomes occluded by the casting. (Perhaps this casting surface would make a good reference.) But it seemed to remain perpendicular at the speeds at which it was visible. This is what I would expect but never checked, the belt angle should not change with speed.(?)
Thanks for the inputs. I have now revisited the SketchUps that I had, made a few corrections and am now in the process of reassembly. This is what I have so far. I have done this with the various parts close at hand; along with my digital calipers. The numbers may not reflect the universe but they do reflect the parts that I have and I hope the parts that are in my two machines.
Attachments
Drive Sheave and Idler Sheave Assembly Ver 1.jpg (66.37 KiB) Viewed 723 times
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
With assistance, I am making some progress in trying to "fully understand" the sheaves and how they work. However, I still have questions. The attached sketch shows the fan and idler sheaves; the two sheaves that are permanently fixed. The speed adjustment are based on these sheaves in conjunction with the idler and floating sheaves.
Idler Sheave and Motor Sheave Assembly Ver 1.jpg (71.72 KiB) Viewed 644 times
My question is where will the V belt ride on these sheaves with the speed adjusted for "mid-range); that is to say when both sheaves (pulleys) are the same size.
Drive Sheave and Idler Sheave Assembly Ver 1.jpg (77.35 KiB) Viewed 644 times
jsburger wrote: Mon Aug 23, 2021 1:21 pm
With both pulleys the same size you have a 1 to 1 ratio so the speed would be the motor RPM. Is that not correct?
I agree with John, therefore Idler speed is 3450. Upper spindle speed would be 3450/1.6, ~2156 RPM. K.5, or so on the dial. It's going to vary some from machine to machine.
