When did main table lose/regain it's ribs?

bobgroh · Post by **bobgroh** » Mon Dec 02, 2013 3:55 pm

Working on my 520 upgrade using parts from eBay (and a replacement trunion from another person) and noticed a few odd things.

Odd Thing #1:
I noticed the main table does not have any surface ribs on the area between the two miter gauge slots.
[ATTACH]23369[/ATTACH]

My other two model 510s both have ribs:
[ATTACH]23370[/ATTACH]

So when did the ribs go away and when did they come back??

Odd Thing #2:
My new table has a 'bump' on one side:
[ATTACH]23371[/ATTACH]

again the other tables had flush sides. Won't this bump interfere with the extension tables? Maybe that is not as important with the 520 fence? Words of wisdom needed!!

Lastly what the heck is the size of the adjustment bolt (limit stop bolts) on the bottom of the table:
[ATTACH]23372[/ATTACH]

I measured the existing bolts to be 5/16-18 UNC. Bought a tap (some of my threaded holes in the table needed to be cleaned out due to damage) but the tap is taking too much metal out of the hole's. So what the heck is that screw size supposed to be?? HELP!!!

algale · Post by **algale** » Mon Dec 02, 2013 4:17 pm

Ribbing (or lack thereof) explained here: http://shopsmith.net/forums/showpost.ht ... ostcount=4

Bumps on side of table not explained officially to my knowledge. When you put tables together, there will be a small gap. If tables are aligned, gap will be bridged by fence and fence will be unaffected.

Do not know size of the bolt.

dusty · Post by **dusty** » Mon Dec 02, 2013 6:10 pm

algale wrote:Ribbing (or lack thereof) explained here: http://shopsmith.net/forums/showpost.htm?p=761&postcount=4

Bumps on side of table not explained officially to my knowledge. When you put tables together, there will be a small gap. If tables are aligned, gap will be bridged by fence and fence will be unaffected.

Do not know size of the bolt.

The bumps on the sides replace the holes that used to be there. These are attachment/reference points used during the manufacturing process.

JPG · Post by **JPG** » Mon Dec 02, 2013 8:40 pm

5/16 - 18 is correct. Why do you think the threads were damaged?

The screws have a nylon spot on the threads. You do not want them to back out on their own!!!:eek: The nylon spot acts like a lock nut.

Have you tried screwing a standard 5/16-18 screw into those holes?

If you are getting significant chips. you may have cross threaded it.

bobgroh · Post by **bobgroh** » Mon Dec 02, 2013 10:40 pm

JPG40504 wrote:5/16 - 18 is correct. Why do you think the threads were damaged?

The screws have a nylon spot on the threads. You do not want them to back out on their own!!!:eek: The nylon spot acts like a lock nut.

Have you tried screwing a standard 5/16-18 screw into those holes?

If you are getting significant chips. you may have cross threaded it.

Why did I think the threads were damaged? Because the screw that was there was bent over at a 45 deg angle. And the screw itself (after backing it out) was bent but not as much? And I couldn't get a good screw to go in cleanly.

My screw's did have a bit of the 'red stuff' (Loktite locking compound) on them. No nylon spot. I do have have some Loktite (the non-permanent type) which I use after reassembly and re-alignment.

The suggestion on trying a 'known good' 5/16-18 bolt is an excellent one. I'm going to get one or two tomorrow. If I can find the right lengths (more or less) I'll probably replace all 5. Got close to $500 in everything so far so what's another couple of bucks.

Many thanks, by the way, for the excellent info so far. It seems as if the new table is the 'latest' table and I might very well keep it for my 520 conversion. I'm getting smarter by the minute. OF course, that is from a low starting base!