My 520 started singing today.

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dusty
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Re: My 520 started singing today.

Post by dusty »

JPG wrote:I think we need to start looking at the headstock to carriage distance.

Table mount tubes to where on headstock?
I think these images, if replicated on the machine in question, would show that every thing there is as expected.
Carriage Stop Ring 002.JPG
Carriage Stop Ring 002.JPG (143.18 KiB) Viewed 5859 times
Carriage Stop Ring 006.JPG
Carriage Stop Ring 006.JPG (144.36 KiB) Viewed 5859 times
Carriage Stop Ring 007.JPG
Carriage Stop Ring 007.JPG (152.27 KiB) Viewed 5859 times
Carriage Stop Ring 008.JPG
Carriage Stop Ring 008.JPG (152.1 KiB) Viewed 5859 times
Carriage Stop Ring 009.JPG
Carriage Stop Ring 009.JPG (135.91 KiB) Viewed 5859 times
Carriage Stop Ring 011.JPG
Carriage Stop Ring 011.JPG (150.32 KiB) Viewed 5859 times
"Making Sawdust Safely"
Dusty
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dynabase
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Location: Post Falls, Idaho

Re: My 520 started singing today.

Post by dynabase »

I called Shopsmith and they said they will probably replace the rear trunnion so I'm waiting on a call back.

Today I am going to the shop and get out the tape and compare the results with Dusty's pictures. Since this takes the trunnion hole size out of the picture because the table is not mounted. I should get the same results in theory.

Michael
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dusty
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Re: My 520 started singing today.

Post by dusty »

dynabase wrote:I called Shopsmith and they said they will probably replace the rear trunnion so I'm waiting on a call back.

Today I am going to the shop and get out the tape and compare the results with Dusty's pictures. Since this takes the trunnion hole size out of the picture because the table is not mounted. I should get the same results in theory.

Michael
The only variables are the width of the rubber bumper and the length of the saw arbor. Make sure the arbor is firm against the knurled knob and lock all the locks.

This setup sorta confirms design characteristics. This shows how the pieces fit together with respect to one another.
"Making Sawdust Safely"
Dusty
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dusty
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Re: My 520 started singing today.

Post by dusty »

dynabase; when you get back to this task, please measure the length of your rubber bumper. I have two different sizes. They are 1.438" and 1.375".

At the moment only the 1.375" bumpers are installed. I believe that the newer bumpers from Shopsmith are 1.438". I have had communications from Shopsmith about the bumper dimension but at the moment I can not locate it.
"Making Sawdust Safely"
Dusty
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sehast
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Re: My 520 started singing today.

Post by sehast »

dusty wrote:
dynabase wrote:I called Shopsmith and they said they will probably replace the rear trunnion so I'm waiting on a call back.

Today I am going to the shop and get out the tape and compare the results with Dusty's pictures. Since this takes the trunnion hole size out of the picture because the table is not mounted. I should get the same results in theory.

Michael
The only variables are the width of the rubber bumper and the length of the saw arbor. Make sure the arbor is firm against the knurled knob and lock all the locks.

This setup sorta confirms design characteristics. This shows how the pieces fit together with respect to one another.
I believe there maybe another variable. The newer tables have trunions with just three holes for adjustment. The fourth hole at the outfeed left side is just big enough for the bolt which allows no lateral adjustment of the table. You can align it parallel to the blade but can not center the blade. I think that is the reason shopsmith started to use the larger bumpers. My old 1990 vintage table had all large holes in the trunnion so you could also adjust it laterally.
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reible
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Re: My 520 started singing today.

Post by reible »

Newer meaning? My 2006 has the larger holes all 4 places.

Ed
sehast wrote:
dusty wrote:
dynabase wrote:I called Shopsmith and they said they will probably replace the rear trunnion so I'm waiting on a call back.

Today I am going to the shop and get out the tape and compare the results with Dusty's pictures. Since this takes the trunnion hole size out of the picture because the table is not mounted. I should get the same results in theory.

Michael
The only variables are the width of the rubber bumper and the length of the saw arbor. Make sure the arbor is firm against the knurled knob and lock all the locks.

This setup sorta confirms design characteristics. This shows how the pieces fit together with respect to one another.
I believe there maybe another variable. The newer tables have trunions with just three holes for adjustment. The fourth hole at the outfeed left side is just big enough for the bolt which allows no lateral adjustment of the table. You can align it parallel to the blade but can not center the blade. I think that is the reason shopsmith started to use the larger bumpers. My old 1990 vintage table had all large holes in the trunnion so you could also adjust it laterally.
{Knight of the Shopsmith} [Hero's don't wear capes, they wear dog tags]
dynabase
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Re: My 520 started singing today.

Post by dynabase »

My machine was built in Dec 1999 so I assume my holes are old.

In retrospect the bumper is the key to this whole thing. The bumper is really what determines if the blade is centered or not. If I had to go through this on another machine I would just trim the bumper until the blade was centered.

Shopsmith is sending me a new trunnion and I should get it in a couple of days. Once it is installed if I still have any alignment issues I am going to shave down the bumper until I am happy with the blade position. If your careful I can't think of any downside to customizing the bumper to your machine. It might be a good idea to buy a spare before you start customizing but they are not that expensive.

Thanks guys. I will report the results after I get the table back together.

Michael

Michael
sehast
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Re: My 520 started singing today.

Post by sehast »

The table I have has 518348 engraved on the back. I don't know the exact date because I bought it on the grey market but it appears to be in new condition, no detectable scratches or normal wear.
dynabase
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Posts: 161
Joined: Sun May 26, 2013 1:06 am
Location: Post Falls, Idaho

Re: My 520 started singing today.

Post by dynabase »

sehast wrote:The table I have has 518348 engraved on the back. I don't know the exact date because I bought it on the grey market but it appears to be in new condition, no detectable scratches or normal wear.
If you look through all the discussion on this issue someone mentioned that some trunnions had only one hole drilled out to 1/2" and they were supprised that none of mine were drilled. The hole thing was a vendor issue. Some of the bad trunnions got out to production. Shopsmith will replace the bad trunnion.

Michael
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dusty
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Re: My 520 started singing today.

Post by dusty »

sehast wrote:
dusty wrote:
dynabase wrote:I called Shopsmith and they said they will probably replace the rear trunnion so I'm waiting on a call back.

Today I am going to the shop and get out the tape and compare the results with Dusty's pictures. Since this takes the trunnion hole size out of the picture because the table is not mounted. I should get the same results in theory.

Michael
The only variables are the width of the rubber bumper and the length of the saw arbor. Make sure the arbor is firm against the knurled knob and lock all the locks.

This setup sorta confirms design characteristics. This shows how the pieces fit together with respect to one another.
I believe there maybe another variable. The newer tables have trunions with just three holes for adjustment. The fourth hole at the outfeed left side is just big enough for the bolt which allows no lateral adjustment of the table. You can align it parallel to the blade but can not center the blade. I think that is the reason shopsmith started to use the larger bumpers. My old 1990 vintage table had all large holes in the trunnion so you could also adjust it laterally.
"Making Sawdust Safely"
Dusty
Sent from my Dell XPS using Firefox.
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