SAG 12 Restoration Progress
As I mentioned in the other thread, I am in the process of restoring my SAG 12 to near new condition. I have found some time the past couple of weeks for further work on the saddle:
I added the oil channels in the Turcite with a ball endmill and also cross drilled the saddle for centralized lubrication:
As mentioned before, I was dissatisfied with the little ball oilers, especially the ones requiring access to the rear of the machine to service, so I have decided to add a Bijur one shot system for the saddle and cross slide ways. The pump will be located on the electrical enclosure and connected to the saddle by a flexible hose and will be routed with the cable going to the DRO scale for the cross slide.
These two points will feed each side of the front way:
The upper front cavity in the saddle is essentially unused currently, so the metering units and juction block for the front prismatic way and cross slide will be located there, and a single line routed to the back to another juction block for the back saddle way and the supply from the pump.
Last edited by TexasTurnado; 12-25-2011 at 08:06 AM.
Work on the saddle/cross slide has come to an abrupt halt due to the discovery I do not have enough Turcite for both of the cross slide ways.
To put the balmy 65 - 75 degree January weather here in Texas to good use, I decided to attack the steady rests for both the SAG 12 and Colchester, as well as some other SAG 12 parts and ready them for a new coat of paint - first I striped them bare and sandblasted:
Today I got the PPG DP40 epoxy primer on and hope to get the top coats on before it turns cooler and rainy on Sunday evening:
Here is a pic of the main casting of the SAG 12 striped and ready for paint that was done this summer:
Right after I got the lathe and checked it out, I took the bed to Commerce Grinding here in dallas and had it ground on their massive 300 inch slideway grinder:
I thought the cost (about $700) was quite reasonable to grind both flat ways, both prismatic ways, and the underside of the ways on each side of the bed to an accuracy probably better than the lathe was when new. The bed, as received, was quite worn (to the point the underside of the saddle was rubbing on the top of the bed outside the area of the front prismatic way) so there was never any question serious work was needed to restore it to accurate condition.
Since you guys liked the pic of the front of the 80 x 300 inch Waldrich Coburg so much, here is the back half where the table and work disappear into on the left side of its stroke:
In the lower left of this photo you can just see part of the large motor driving it and many hydraulic hoses running underneath the hooded area.
Commerce Grinding also has a 300 inch Blanchard grinder, billed on their website as the worlds largest:
Note the "little" cylindrical square at the left of the pic....
Someones bed from their CNC slant bed lathe was in the queue ahead of me:
Here is a link to their website for more pics and a partial list of their inventory of machines......
The whole site must occupy a city block with several buildings - I have only been in two of them (slideway grinders in one and od/id grinders in another). If you ever make it to Dallas it's worth a stop to see their operation....
That is some really impressive stuff!
I got to see a 144" Blanchard grinder today... That one makes it look tiny.
I was able to get the parts prepared with multiple coats of high build polyurethane primer and topcoat before the temp took a nosedive and the rains came in on Monday:
We had a nice day today (66 deg) so I was able to get outside to sandblast the cross slide ways in preparation to applying the Turcite. Hopefully I will have the Turcite on and the ways scraped by next week - the work now does not depend on the outside weather as I have heat in the shop....
Here is a pic of the SAG front way as received after moving the saddle to the right:
If you look closely at the flat area immediately behind the front prismatic way, you will see where the saddle was wearing on the bed, as well as on the way. Apparently, the PO didn't believe in lubricating the ways judging from the degree of wear on both the bed and saddle.....
And here is a pic of the main casting all decked out in Metal Glaze ready for a second coat of epoxy primer (the first coat of epoxy primer is under the Metal Glaze):
That really is a first class rebuild, it's going to be like new once you're done. Does the bed move to allow spindle alignment?.
Sag 12 parts source
I have a CMT lathe that I purchased new from the factory in Tortona, Italy new in 1979. Graziano is also from Tortona. Ugo Montagano at [firstname.lastname@example.org] can supply parts and pices for the SAG 12 machines. He proivides the bits I need for my machine. He is responsive and communicates well. Just another source of SAG 12 or Graziano parts to explore. Beautiful work on your machine. JIM
Thanks for that info, Jim - I didn't get the chip deflectors for the ways with my lathe, so I will see if Ugo can possibly supply them at a reasonable price. I have been planning to make a set from stainless steel but it would be much easier to buy a used set.
Originally Posted by James Allen
Oil mod is a great idea John! Nearby bloke who got his reground, ended up with tailstock height issues initially, believe it was addressed by making another base.
Might have been a mix up in translation somewhere along the way....and I didn't supply part numbers, <I think> I was quoted 15 Euro for front covers from Ugo.
Freight out of Europe makes it hard to justify though for a one-off (or 2).
A bit of 3mm steel, 4 bends and a satin electroless nickel finish probably not that far different, if it needed to be shiny.
Maybe this will flush elliot out, anyone dealt with this person recently?
SAG 12 oil & wanted parts
After applying the second coat of epoxy primer, the base looked like this and was ready for multiple coats of high build Southern Polyurethanes primer.
This polyurethane primer was sanded out until the surfaces were flat and smooth as a babys butt....
Then the top coats of solid color polyurethane were applied:
The electroless nickel is why I considered making them from SS - I figured by the time I got them plated it would cost as much or more than SS, which I can work myself...
Originally Posted by BillE
Did you get your gearbox back together OK?
Buttoned up again. Leadscrew engagement has me still scratching my head, as there's only one gear the fork can go onto (top middle)...and it's in place....just won't go out of feed.
Originally Posted by TexasTurnado
Cross slide Turcite is on.....
and there's a nice little bead of adhesive all along the edge of the Turcite so I think I got the correct amount on:
Tomorrow it should be cured and ready for fitting...
Hmm, I not clear on what you are asking - which gear are you calling top middle - right or left of the partition? Can you clarify please? Are you sure it is driven and not just turning from friction of the shaft/bearings?
Originally Posted by BillE
more pics of those sensuous ground ways!
what is the status of post grind bed hardening?
when i paint cars i use a high build first, sand and then epoxy as a sealer under the top coat.Most epoxy primer doesnt need to be sanded before top coat before 72 hours and is a great sealer for light paints that might bleed bondo pigments. but im sure both ways work.. great job on those ways ,wow
The rate you're going, this beauty should be operational in a week or two!
The leadscrew/ feed selection mechanism is right of the partition.
Originally Posted by TexasTurnado
When I did mess with it with the cover off, the gear on the leadscrew shaft at the far right has to engage an internal spline drive flange.....just where the oil wick goes into the casting.
Detail in the picture isn't all that good, as I wasn't expecting an issue with this particular area - although there was some stiction moving by hand.
I'm more than likely clutching at straws, but when the clutch on the feed (under the aluminium cover on the exterior of the gearbox) is powered up, I'm hoping the issue resolves. Of course, I can't even see the terminal block on this clutch with mirrors, let alone access it. The late schematic numbering must be different too, as applying power from the maze in the electrical cabinet at the back, has no effect....hopefully that clutch doesn't require a rewind.