dusty wrote: Sat Nov 07, 2020 6:19 am
BUT I don't understand your differentiation between the two drive shafts. If one aligns vertically with a given SPT I would think the other would too.
Because the upper belt tension adjustment is done by moving the Idler Shaft in an eccentric bushing, the lower shaft is displaced both vertically and horizontally. So the Lower aux. is only centered in the headstock if the eccentric busing is at the 6:00 or 12:00 position, both unlikely.
I can't confirm what Russ said in an earlier post about the Mark Jointer always coming with eccentric mounts, but I believe it to be accurate. My Greenie BS came with straight tubes, but my Greenie Jointer came with eccentric mounts. This old version eccentric is solid, a bit longer in both directions, and has about half the eccentricity compared to the 'modern' version. I would draw the conclusion that back when most SPTs used straight tube mounts, the Jointer did not due to the eccentric bushing in the headstock. Also, there is practical way to retain height setting on the Jointer without eccentrics. There is not enough clearance for the stop collars used on other straight tube mounts (used as on the tailstock).
OKAY. You are correct in that the eccentric affects the vertical alignment of the two shafts. I was ignoring that because in both of my machines the belt is tensioned at about 7:00 or 7:30 at I don't believe the eccentric moves the shaft all that far. Nonetheless - you are correct.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
I can't confirm what Russ said in an earlier post about the Mark Jointer always coming with eccentric mounts, but I believe it to be accurate. My Greenie BS came with straight tubes, but my Greenie Jointer came with eccentric mounts. This old version eccentric is solid, a bit longer in both directions, and has about half the eccentricity compared to the 'modern' version. I would draw the conclusion that back when most SPTs used straight tube mounts, the Jointer did not due to the eccentric bushing in the headstock.
As I said IIRC the Jointer always had eccentric posts, except the Model 4E jointer made for the Model 10E and 10ER Shopsmith which mounted differently. I restored a Model 620 Jointer S/N 11458 a few years ago. That serial number is below the first ones listed as made in April 1954. I wish I had taken more pictures since I didn't get one of the mounting posts but I do believe they were eccentric. I also wish I hadn't sold it after it's restoration. As David points out there is a need for horizontal as well as vertical adjustment when using the Idler Shaft to power the Jointer because of the eccentric bushing. This is also true for the Magna Air Compressor which was run off the Idler Shaft. Although it has straight posts they can be adjusted horizontally at the bolt holding the posts to the compressor frame.
Russ
Mark V completely upgraded to Mark 7
Mark V 520
All SPT's, 2 Power Stations & Crafter's Station
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E's S/N's 1076 & 1077 oldest ones I have restored. Mark 2 S/N 85959 restored.
The 'location of the idler shaft is variable due to tension adjustment.
The short straight jointer mounting tubes have a snap ring that provides a vertical stop/support(as do longer straight spt mounting tubes).
I do not have a M5 eccentric 'handy' but a MVII eccentric will move 1/4" both vertically and horizontally by rotating 90°.
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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: Tue Nov 10, 2020 8:22 pmThe 'location of the idler shaft is variable due to tension adjustment.
The short straight jointer mounting tubes have a snap ring that provides a vertical stop/support(as do longer straight spt mounting tubes).
I do not have a M5 eccentric 'handy' but a MVII eccentric will move 1/4" both vertically and horizontally by rotating 90°.
Yes, the eccentric does effect the orientation of the idler shaft but only by a mere 1/8" maximum in any direction, depending on how far the eccentric is rotated. Mine both set between 7:00 and 8:00 o'clock.
"Making Sawdust Safely" Dusty
Sent from my Dell XPS using Firefox.
JPG wrote: Tue Nov 10, 2020 8:22 pm
The short straight jointer mounting tubes have a snap ring that provides a vertical stop/support(as do longer straight spt mounting tubes).
I have three SS bandsaws, all three have the same eccentric tubes, and none of them leave enough room on the eccentric to put on most stop collars, but I assume there must be some thinner ones available.
It is a real pain to get the shafts aligned for the bandsaw even with the eccentric tubes. The saw is heavy and it's difficult to adjust the eccentrics without taking the saw on and off and incrementally adjusting the tubes. And then the vertical alignment is even tougher. I'm working on an alternative means of connection for the bandsaw and any other accessories. I jury rigged a couple of U-joints on a shaft using socket swivels to see if It would allow me to connect the accessories without close alignment. The power coupler can account for very minor offsets but not much and it robs power and stresses bearings when it's misaligned. So far I tested my makeshift U-Joint coupler on the bandsaw but the shafts were already aligned and I didn't want to change them. I just got my recently acquired belt sander running and I'll try it out on that soon with some intentional misalignment to see what happens. The U-Joint shaft worked, but those swivels weren't made for that kind of use, I have to make some kind of arbor to connect to the shafts, my test was done with two drill chucks. If this works out I'd like to find out if a device like this can be made from inexpensive printed parts. It's not intended to drive devices around a corner, just to account for minor misalignment so it doesn't take an hour to get a bandsaw aligned.
straight tubes with snap rings.jpg (165.78 KiB) Viewed 1041 times
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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
We started talking about Jointer mounting post but have continued on to the Bandsaw. My 1956 Bandsaw has straight posts with stop collars as David showed above. As far as I know these were the original posts for it. This type of post would then likely be the original one used for the Bandsaw which came out in the Summer of 1955. I also own a 1996 and 2006 plus I owned and sold a 1985 Bandsaw which all have the standard eccentric posts. Straight Posts with snap rings were common early on but were later replaced by the eccentric posts in most cases. Below are three different lengths of the straight posts with the snap rings for different SPT's.
Lengths given are overall length
Straight Mounting Posts.jpg (312.51 KiB) Viewed 1037 times
Russ
Mark V completely upgraded to Mark 7
Mark V 520
All SPT's, 2 Power Stations & Crafter's Station
Model 10ER S/N R64000 first one I restored on bench w/ metal ends & retractable casters.
Has Speed Changer, 4E Jointer, Jig Saw with lamp, a complete set of original accessories & much more.
Model 10E's S/N's 1076 & 1077 oldest ones I have restored. Mark 2 S/N 85959 restored.
