I have just installed the wider bellows for the Y axis of my 3 digit 1100. Perhaps what I learnt maybe of interest to those contemplating the same upgrade. The collapse of my rear bellows suggests it will be needed sooner or later for the 1-149 numbered machines.
The Tormach website tech document for the "Y Axis Bellows Upgrade Kit (30580)" states the chip trays need to be removed to drill the front mounting holes for the new bellows. In my case (mill #109 with deluxe stand) this is wrong. The newer cordless drills are short enough to drill the new mounting holes for both front and rear bellows.
Also the Upgrade Kit includes "pad blocks" (item 8 on Base Assembly exploded drawing in series 1 User Manual) that fit between the base of the mill and the "Y axis cover mounting plate" (item 9) to which the frontend of the front bellows is screwed. The important purpose of the pad blocks is to provide space for the folded bellows when the Y saddle is fully forward. Replacing the pad blocks would be awkward (with the deluxe stand fitted) because there is little room for an allen key to rotate the SHSCs. The Kit also includes a new drilled and tapped Y axis cover mounting plate.
I did not need any of these new parts as my mill had them already fitted and all I had to do was drill three M4 holes in the existing cover mounting plate to match the new bellows.
After installing both bellows I emailed Tormach regarding the misleading tech document. The reply was that due to design changes during that period, and minimum QC of bellows installation, some mills may require all of the parts. However, they will review the situation and update the tech document.
So the advice at present is that those considering upgrading to the wider bellows should:
1. check for adequate space for their drill both at rear and front of saddle;
2. check that the two pad blocks are fitted at the front of mill base;
3. decide if the Kit is needed or just two new bellows.
The Upgrade Kit sells at $143.51 and the wider bellows(30578) at $34.34 each.
In the meantime I offer the following comments re the installation.
The location of the M4 holes to be drilled means that the cordless drill will be in contact with the dovetail of the Y axis way. Consequently the hole has to be drilled at an angle but fortunately the angle can approximate the angle a screwdriver would be to avoid the folds of the bellows. So when drilling, keep the drill square to the side of the saddle when looking down at the drill body; the resulting angle to the horizontal plane will make it easier to remove/replace the screws.
The adapter plates that are mentioned in the Addendum to the tech document "Y Axis Bellows Upgrade" would make installation easier but the email I received from Tormach included a comment that the hole locations for installing the original covers probably vary from machine to machine. So the measurements of the old installation need to be checked before drilling the adapter plates. Another issue is that to avoid drilling any holes in situ, four adapter plates would be needed. I planned to use Delrin instead of aluminium until I found I didn't need to make them.
Three concerns regarding the upgrade and the way I did it.
1. Care needs to be taken when drilling the saddle to avoid the cuttings don't fall onto the bearing surface of the dovetail.
2. When the saddle is positioned all the way to the front (with no bellows installed), the Y axis ball screw is uncovered and needs to be protected from all dirt/cuttings.
3. The bellows/saddle joint at the rear of the saddle is the only joint that poses a risk if it leaks. Coolant and/or chips could drip onto the ball screw. That joint needs to be sealed. I used a rubber weather sealing strip, easily removed/replaced if I have to remove the rear bellows in future.
And when you drill and tap for the M4 screws, be careful.... a broken drill/tap would make an adapter plate a necessity.
Good luck
Bevin
The Tormach website tech document for the "Y Axis Bellows Upgrade Kit (30580)" states the chip trays need to be removed to drill the front mounting holes for the new bellows. In my case (mill #109 with deluxe stand) this is wrong. The newer cordless drills are short enough to drill the new mounting holes for both front and rear bellows.
Also the Upgrade Kit includes "pad blocks" (item 8 on Base Assembly exploded drawing in series 1 User Manual) that fit between the base of the mill and the "Y axis cover mounting plate" (item 9) to which the frontend of the front bellows is screwed. The important purpose of the pad blocks is to provide space for the folded bellows when the Y saddle is fully forward. Replacing the pad blocks would be awkward (with the deluxe stand fitted) because there is little room for an allen key to rotate the SHSCs. The Kit also includes a new drilled and tapped Y axis cover mounting plate.
I did not need any of these new parts as my mill had them already fitted and all I had to do was drill three M4 holes in the existing cover mounting plate to match the new bellows.
After installing both bellows I emailed Tormach regarding the misleading tech document. The reply was that due to design changes during that period, and minimum QC of bellows installation, some mills may require all of the parts. However, they will review the situation and update the tech document.
So the advice at present is that those considering upgrading to the wider bellows should:
1. check for adequate space for their drill both at rear and front of saddle;
2. check that the two pad blocks are fitted at the front of mill base;
3. decide if the Kit is needed or just two new bellows.
The Upgrade Kit sells at $143.51 and the wider bellows(30578) at $34.34 each.
In the meantime I offer the following comments re the installation.
The location of the M4 holes to be drilled means that the cordless drill will be in contact with the dovetail of the Y axis way. Consequently the hole has to be drilled at an angle but fortunately the angle can approximate the angle a screwdriver would be to avoid the folds of the bellows. So when drilling, keep the drill square to the side of the saddle when looking down at the drill body; the resulting angle to the horizontal plane will make it easier to remove/replace the screws.
The adapter plates that are mentioned in the Addendum to the tech document "Y Axis Bellows Upgrade" would make installation easier but the email I received from Tormach included a comment that the hole locations for installing the original covers probably vary from machine to machine. So the measurements of the old installation need to be checked before drilling the adapter plates. Another issue is that to avoid drilling any holes in situ, four adapter plates would be needed. I planned to use Delrin instead of aluminium until I found I didn't need to make them.
Three concerns regarding the upgrade and the way I did it.
1. Care needs to be taken when drilling the saddle to avoid the cuttings don't fall onto the bearing surface of the dovetail.
2. When the saddle is positioned all the way to the front (with no bellows installed), the Y axis ball screw is uncovered and needs to be protected from all dirt/cuttings.
3. The bellows/saddle joint at the rear of the saddle is the only joint that poses a risk if it leaks. Coolant and/or chips could drip onto the ball screw. That joint needs to be sealed. I used a rubber weather sealing strip, easily removed/replaced if I have to remove the rear bellows in future.
And when you drill and tap for the M4 screws, be careful.... a broken drill/tap would make an adapter plate a necessity.
Good luck
Bevin