Upgrading to a 510 to 520

[twistsol]

I have a Mark 5 510 that I bought used. The machine is was originally a 500 that was upgraded to a 510. I don't know when it was upgraded and there are two 520 options for the upgrade based on date. I assume something changed on the 510 tables in 1986. What do I need to look for to determine which upgrade to buy?

[thunderbirdbat]

My son did the same thing to his purchased used 510 that had originally been a 500. From what he told me when he asked about which upgrade to get he was told it depended on how the rails were fastened to the tables. If the rails had the holes in them to access the fasteners then it is the pre-1986 version. The early 510 table holes were threaded so the fasteners were tightened by access through the front of the rails. The later rails had the studs welded to them and were passed through un-threaded holes on the tables and nuts were used to hold the rails on.

[dusty]

Very Good Explanation of how to distinguish between early model 510 and later model 510.

Later model 510 (no holes in rails) - rails attach to the tables using nuts on the underside of the table.

There are pictures that show this somewhere. I'll try to find and post them.

[twistsol]

Excellent description, thank you.

[JPG]

Excellent description, thank you.

Quite accurate as well! Only the nuts are 'kep' nuts(integral star washer).

[twistsol]

And after a quick inspection now that I'm home, my memory served me well for a change and it looks like the 510 was upgraded with the newer table style.