TMT.OPT.PRE REL011 SSA Tower Rework Instructions (for composite sleeve bearings) F. Kamphues

SSA Tower rework Reason: Implementation of composite sleeve bearings for the Tower Locks TMT.OPT.PRE REL012

Scope of Work Required modifications in accordance with drawing M1S Prototype V3 Rework Composite Brg REV A –Tower M1S : Tower Lock holes to be increased from 22 to 27 mm Drill, tap and install M4 helicoil in each “ear” for end stop Install GGB GF sleeve bearings (press fit) Drill and tap through side of sleeve bearing (for Spring Plunger) 3X 1/2-13 UNC-2B THROUGH TO BORE, BACK SIDE CHAMFER 2.00 X 45 –Lock Assembly M1S : Deburr edges of spring plunger detents TMT.OPT.PRE REL013

Scope of Work TMT.OPT.PRE REL014 M1S Prototype V3 Rework Composite Brg REV A:

TMT furnished equipment TMT provides GGB GF sleeve bearings TMT provides 1/2-13 UNC-2B Delrin Spring Plungers TMT provides Machining Fixture –With registration pins and datum surface for accurate location of Tower –A setup for bearing holes and M4 helicoil hole machining –B setup for drilling & tapping spring plunger holes TMT.OPT.PRE REL01 5 A B

TMT Machining Fixture Machining Fixture (arrow side is datum) TMT.OPT.PRE REL01 6

Preparation of Towers Anodize Tower in accordance with drawing Install Registration Inserts M1S TMT.OPT.PRE REL01 7

Installation Procedure Setup A - 1/5 Installing brass registration pins in Machining Fixture (location A) TMT.OPT.PRE REL018

Installation Procedure Setup A - 2/5 Install and Align Machining Fixture on CNC machine. Arrow side is datum and should be perpendicular to machining axis. TMT.OPT.PRE REL019

Installation Procedure Setup A - 3/5 Install Tower on brass registration pins. Install clamps TMT.OPT.PRE REL0110

Installation Procedure Setup A - 4/5 Install anti-chatter support (with very light preload to prevent deformation in the clamped state!). –Support is not provided by TMT (use a threaded rod with two nuts, or similar) TMT.OPT.PRE REL0111

Installation Procedure Setup A - 5/5 Check alignment and CNC software before starting machining! TMT.OPT.PRE REL0112

Machining Setup A Machine holes to – mm Drill and tap for M4 helicoil Repeat for other two “ears” (rotate 120°, 240°) TMT.OPT.PRE REL0113

Install sleeve bearings Press fit sleeve bearings (3x) in accordance with GGB Composite Bearing Handbook section 6.1 –Bearings shall be installed mm deeper than flange (to accommodate lock barrel radius) TMT.OPT.PRE REL0114

Fit check lock barrels Fit check lock barrels (bearing does not require lubricant) TMT.OPT.PRE REL0115

Installation Procedure Setup B - 1/3 Move brass registration pins from location A to B) TMT.OPT.PRE REL0116

Installation Procedure Setup B - 2/3 Install Tower on brass registration pins. Install clamp TMT.OPT.PRE REL0117

Installation Procedure Setup A - 3/3 Check alignment and CNC software before starting machining! TMT.OPT.PRE REL0118

Machining Setup B Drill and tap for Spring Plunger –Carbide drills should be used for drilling GGB filament wound bearings. To avoid fiber breakout, use a mandrel to support the ID. TMT.OPT.PRE REL0119

Machining Setup B Apply backside chamfer in tapped hole (may be done by hand; chamfer size is not critical) Repeat for other two “ears” (rotate 120°, 240°) TMT.OPT.PRE REL0120

Fit check Spring Plunger Fit check Spring Plungers (should be able to go all the way through) TMT.OPT.PRE REL0121

Deburring Spring Plunger Detents Hand deburr detent edges with round grinding wheel and fine Emery cloth. Edges shall be round and smooth! TMT.OPT.PRE REL0122