Jointer Slipping down and breaking coupler

[DLB]

None of what has been posted here resemble the eccentrics that I have. The ones I have are either 3 1/2" or 6 3/4".

I think those are normal since at least the 80's but I would guess farther back. There is also a longer eccentric used, at least, for the strip sander that is somewhere near 9". Maybe someone (Russ?) should do a comprehensive thread on mounting tubes. My earliest experience was an early 80's belt sander I bought new, it has what seems like that same 6-3/4" eccentric.

Band saw posts from 19??.

This seems too long, measured above the snap ring, unless something else was different in the band saw it came from. Mine measure something around 5" from the mating surface of the Headrest to the stop feature in the BS casting. The one pictured is around 6-13/16", so we're not in the same area code. Jigsaw, maybe? (I have no idea, but I don't think the strip sander goes back that far and it's the only thing I know uses a long mounting tube.)

- David

[dusty]

I don't think we are using the same eccentrics. None of mine have snap rings. All of mine have an offset like that depicted in a sketch of my short eccentrics (earlier in this thread).

[DLB]

I don't think we are using the same eccentrics. None of mine have snap rings. All of mine have an offset like that depicted in a sketch of my short eccentrics (earlier in this thread).

Right, I believe all of those pictured with either snap rings or stop collars are straight (non-eccentric) tube mounts. The eccentrics don't need an added feature, like a snap ring or stop collar, to rest on the accessory mount because the eccentric shoulder does that. I think all of the straight tube versions are old-school, though as I've said I personally prefer the stop collar straight tube version, especially for the bandsaw. (But not for those SPTs that connect to the lower aux drive.)

- David

[dusty]

This is an eccentric tube from my bandsaw. The one used in my jointer is similar but shorter. I think both sides are the length of the short side in this photo.The jointer is also heavier so I decided to remove the bandsaw eccentric for the photo shut.

No straight tube and no snap ring. The offset measures 1/4". This establishes the limit on how far the drive shaft could be moved (in the lacteral direction).

Shopsmith Bandfsaw Eccentric

20201112_045235[1].jpg (216.83 KiB) Viewed 1146 times

[dusty]

This might be an interesting read???

viewtopic.php?f=10&t=10617&hilit=eccentric

[chapmanruss]

Well David, funny you thought someone should do a comparison of the mounting tube lengths. I was actually thinking about that before signing on to the forum this morning. Since I have at least one of each of the SPT's, including the air compressors, it is something I could and now plan to do. Give me some time to do it since it requires removing a post from each SPT for measurements and pictures. Add to that the time to realign the SPT's after reinstalling the posts. I will try to get to that soon but currently am finishing up reassembling a restored a Model 10E. It will not be a complete comparison since I do not have both eccentric and straight tube versions for each SPT. The only Tube Mount SPT I currently have more than one of is the Bandsaws mentioned before. I have two 4" Jointers but the early one is the Model 4E which mounts differently to the Model 10's. Something to note here is there were different length (longer) mounting tubes for the tube mount Model 620 Jointer for the Model 10 Power Mount Adapters. They were straight tubes with snap rings. The three straight posts I posted the picture of previously were not identified as to which SPT they belong to so I will include that information also. When I get it done I will post the information to a new thread.

Dusty, we did post pictures of the straight Posts with snap ring and collar stops. As you are aware we sometimes to go a little off the original topic in threads. Hopefully it is not confusing for other readers since it started with Jointer mounting problems and has progressed into a discussion about SPT Mounting Posts in general.

[dusty]

Dusty, we did post pictures of the straight Posts with snap ring and collar stops. As you are aware we sometimes to go a little off the original topic in threads. Hopefully it is not confusing for other readers since it started with Jointer mounting problems and has progressed into a discussion about SPT Mounting Posts in general.

Yup, it does get confusing some times. Partially because many of us do not read the entire discussion before throwing in our 2-cents worth. I posted the picture of the eccentric because the discussion on straight spt tubes with snal rings was confusing.

[edma194]

I hope I wasn't going too far off topic but once you bring up eccentric tubes there's a lot to say about them.

[chapmanruss]

Dusty,

Your eccentric mounting tube drawing is a great example of guiding the OP to solve his problem. I always like the fine job you do with your drawings in cases like this. Although we did turn this into a discussion about eccentric and straight mounting tubes I think overall it is helpful to all in deciding if the correct mounting tube is being used. In some cases either mounting tube will work. In the OP's case the eccentric tubes will help.

Now I need to correct something I had said previously about the original Jointer Mounting Posts. I said IIRC the Model 620 Jointer that came out about the same time as the Mark 5 in 1954 came with eccentric posts. I did a little more digging and found this may not be true. The 4" straight mounting tube I showed in the picture from my previous post may actually be an original Jointer mounting post. It is a little longer than the Jointer Eccentric Mounting Tube and would be used short end up. The Model 620 Jointer from early 1954 I restored was missing 1 mounting post when I got it. I replaced it with one from an extra set and the 4" mounting tube from the picture is the one left over. A Goldie Model 620-C Jointer from 1960 I restored came with the wrong, too long, mounting tubes and were replaced with eccentric tubes. I believe that previous owner was using the Drive Sleeve Hub to run the Jointer. At this point I cannot tell when the Jointer started coming with eccentric mounting posts. I'll try to find more on that and add it to the Mounting Post Comparisons. I have found reasons for some straight post tubes that used collars instead of snap rings like the Bandsaw and will include that too.

[chapmanruss]

I posted the comparison of the SPT mounting posts yesterday. It is at the link below.

viewtopic.php?f=10&t=24292