With the cost of new machinery skyrocketing, it is now more important than ever to get the maximum production out of existing equipment.  An automatic screw machine remanufactured by Jem Automatics will hold tolerances equal or better than the original OEM standards.  Our attention to detail, and commitment to customer satisfaction will guarantee you a positive experience from start to finish.

A versatile automatic screw machine rebuilt or reconditioned by JEM can increase productivity with the efficiency and durability of a new machine.  We start with a quality second hand machine, completely tear it down to the base frame, then rebuild that machine to the original specifications and standards of a new machine.  This gives you a virtually new machine at a fraction of the cost of a new multi spindle.

Acme Gridley screw machines are excellent candidates for rebuilding, with their ample space and rugged construction.  There are different levels of repair to choose from, depending on the current condition of the machine and the severity of the wear.  We guarantee the performance of all screw machines we rebuild, and we can also perform retrofits and engineer custom attachments or other automation and solutions to be installed during the rebuild process.

Our Rebuilding Process for an Acme Gridley Screw Machine:

This list is non-exhaustive and is only an overview of the services we can provide for the typical multispindle bar machine.  Some items below may or may not be included or applicable based on your specific screw machine.  Furthermore, additional services pertaining to spindle stopping machines, high speed chucking machines, collet chuckers, and hydraulic chucker screw machines may not be itemized below.  Please refer to your quotation for the specific lineup pertaining to your screw machine project.

• Clean, Tear Down, and Inspect:
  1. Machine is to be received free of cutting oil and chips, or taken from our stock.
  2. Machine is steamed and cleaned completely prior to tear down.
  3. Machine shall be inspected for all missing standard parts.
  4. Machine is torn down completely and all parts assembled on inspection racks.
  5. The main frame castings will be separated & checked 100% for cracks, wear, and alignment, and then thoroughly cleaned again, including the lube reservoir.
  6. Casting mating surfaces will be stoned and/or machined as necessary.
  7. In case of cracked main casting frame or spindle carrier damage, customer will be immediately notified and work will stop until advisement from customer.
• Carrier and Headstock:
  1. Carrier assembly is cleaned and totally disassembled.
  2. Carrier stem is inspected, measured and case hardness determined.
  3. If case hardness of stem is determined to be within tolerance, the stem will be reground.
  4. If case hardness would be out of acceptable limits, the stem will be pre-ground, chromed, and finished ground.
  5. Carrier O.D. bearing diameters are inspected and measured.
  6. Headstock carrier bores are inspected and measured.
  7. Carrier bores in the headstock shall be bored, bushed, and rebored if necessary at additional cost.
  8. Main drum shaft bores and cross slide shaft bores in the headstock will be checked, indicated, bushed, bored, and rebored if necessary.
  9. Carrier spindle bores checked for spun bearings and indicated for alignment.
  10. Carrier spindle bores if out of acceptable limit shall be bored, bushed, and rebored at additional cost.
  11. New oil flingers and seals installed.
  12. Old style oiling to be converted to new style through carrier oiling.
  13. Spindle gears are reworked or replaced as needed.
  14. New class 3 spindle bearings installed.
• Main Tool Slide:
  1. Main toolslide bushing replaced and bored to fit new carrier stem diameter.
  2. Main toolslide will be ground flat on all faces and scraped.
  3. All main tool slide key ways and surface irregularities repaired.
  4. Flat and taper gibs to be replaced.
  5. Grind and resurface existing guide block.
  6. Main toolslide foot to be inspected and new standard size push rod bushing installed.
  7. The nut, spacer and positive stop rod replaced or repaired as necessary.
  8. New standard size push rod bushing installed in gear box.
  9. Tool slide operating arm fitted with new roll and stud.
  10. All main tool slide holders shall be bushed and rebored, after completion of quality assurance testing.
• Index Mechanism:
  1. Locking pin is ground and mated to new locking pin sleeve.
  2. Locking lever fitted with new rolls and studs.
  3. Locking pin spring replaced.
  4. Locking pin cam reworked or replaced if necessary.
  5. Index disc guide blocks removed, inspected, and reworked.
  6. Replace index gear shaft.
  7. All rolls, studs and bushings replaced with new.
  8. All bushing and spacers are replaced.
  9. Carrier locking blocks removed, stamped, inspected and replaced if necessary.
  10. Segmented carrier revolving gear removed, inspected and replaced if necessary.
  11. Index disc gear removed, inspected, and replaced if necessary.
  12. Index disc removed, inspected, and replaced if necessary.
  13. Index revolving arm inspected, bushed, and new roll and stud installed.
• Cross Slides - Upper, Lower, and Intermediate:
  1. All slides and slide bases removed and all bearings and top surfaces ground.
  2. Slides are gibed with hardness precision steel and brought back to center.
  3. All slides and slide bases hand scraped and flaked for proper fit.
  4. All roll blocks, operating levers, and shafts inspected for straightness, rebushed.  New rolls, studs, and springs installed.  If beyond repair, will replace with new.
  5. Adjusting screw, adjusting screw plates, and lever bearings replaced as necessary.
  6. Cross slide gears and shafts inspected and reworked or replaced.  New bearings installed.
  7. Cross slide operating drums to be rebuild or replaced.
  8. All cross slide key ways and surface irregularities repaired.
• Gear Box Section:
  1. All gear box bores inspected for wear, spun bearings, and alignment.  Misaligned or worn bores to be bored, bushed, and rebored back to standard.
  2. All new bearings installed.
  3. All gearbox shafts, including spindle drive shaft, to be inspected for wear, twist and spline alignment, and either repaired or replaced.
  4. High speed and feed clutches to be rebuild with new plates, pins, levers and springs.  Clutch housing to be rebuilt or replaced.
  5. Roll clutch to be rebuilt with new style carbide insert roll cam and new pins, springs and rollers.
  6. Brake band assembly to replaced with new.
  7. Large and small bronze gears and steel worms to be replaced with new.
  8. Spiral bevel gears to be replaced.
  9. All other gears inspected for pressure point wear, spline twist, and other wear.  If suitable will be reworked or replaced if needed.
  10. All rolls, studs, and shoes replaced with new.
• Main Drum Shaft and Drums:
  1. Main drum shaft inspected for key way damage, twist, and worn journals.  Worn journal diameters are turned down, metal sprayed, and returned to standard size.  Key ways and irregularities are repaired.  If drum shaft is twisted will be replaced with new.
  2. Main drum shaft bearing journals are inspected, and are repaired to standard size if necessary.
  3. All drums to be inspected, redrilled, reamed, and pinned.  All new pins and keys installed.
  4. Center cross slide drive gear removed, checked, and replaced if necessary.
  5. Main drum shaft collars reworked or replaced and set for proper drum spacing and line up.
• Top Drum Shaft: (if equipped)
  1. Top drum shaft inspected for key way damage, twist, and worn journals.  Worn journal diameters are turned down, metal sprayed, and returned to standard size.  All key ways and irregularities repaired.  If top drum shaft is twisted will replace with new.
  2. All drums will be inspected, redrilled, reamed, and pinned.  New pins and keys installed.
  3. All shaft bearing journals inspected and repaired.
  4. All top shaft driving gears inspected, reworked, or repaired whether new style gear box drive or old style head stock drive.
  5. All spur bevel cross slide drive gears and shafts to be replaced if necessary.
  6. Headstock top drum drive gear and shaft inspected and/or replaced.
  7. All new bearings installed.
• Back End Section:
  1. Finger holder assemblies rebuild to new specifications.
  2. Feed slide, chuck slide, and hand chuck slide assemblies rebuilt.
  3. Collet tubes are repaired or replaced as needed.
  4. Pusher tubes are repaired or replaced as needed.
• Lube System:
  1. New lube pump to be OEM pump.
  2. All new lube lines and fittings are installed.
  3. New oil filter and intake screen installed.
  4. Pressure switch to shut machine down when not enough oil pressure in system.
• Coolant System:
  1. Coolant pump to be rebuild or replaced as necessary.
  2. Coolant pipe to be replaced and new manifolds if necessary.  Pet cocks and ball valves replaced as needed.
• Sheaves and Drive Sleeves:
  1. Drive and safety sleeve assembly to be rebuild or replaced.
  2. All belts replaced with new.
  3. Broken or cracked sheaves replaced with new.
• Motor and Electrics:
  1. All motors tested or replaced to new specifications.
  2. All electrical components inspected and tested for current dependability, and replaced if necessary.
• Reassembly:
  1. Screw machine shall be completely reassembled to OEM specifications.
• Quality Assurance:
  1. Radial, spacing and straightness test are performed on all spindles. These tests will meet or exceed OEM specifications.
  2. Our customers are invited and encouraged to visit during the machine rebuild program and especially to witness our quality assurance testing.
  3. Test results are submitted with all machines.
• Paint:
  1. Machines are painted to customer specifications.
  2. Paint specifications are requested to be included in the purchase order.

Interested in an Acme Gridley screw machine rebuild? Simply fill out and submit the short form below - we will then review your specific requirements and follow up with a quotation and/or recommendation for your consideration.