Tornado Screw Hex Head Cap #10-24 x 1/2″ Zinc Plated 17957

This is the hex head, zinc-plated #10-24 x 1/2 inch screw. That matters, because this machine also uses a Phillips flat head stainless screw of exactly the same thread and length under a different part number. Part number 17957 is the hex head version.

Compatible Models for the Screw Hex Head Cap #10-24 x 1/2″ Zinc Plated

This part fits the following Tornado machines:

• Tornado 98164 MWH-800 8-Gallon Self-Contained Carpet Extractor
• Tornado 98166 20″ Marathon 800 Carpet Extractor (8 Gallon, 115V)
• Tornado 98167 20″ Marathon 800 Carpet Extractor (8 Gallon, 230V)
• Tornado 98168 12 Gallon Self Contained Carpet Extractor
• Tornado 98168 20″ Marathon 1200 Carpet Extractor (12 Gallon, 115V) — all series
• Tornado 98169 20″ Marathon 1200 Carpet Extractor (12 Gallon, 230V)

Hex head means it is driven with a socket or spanner rather than a driver, which is a deliberate choice: it can be torqued properly and it will not cam out and chew its own head. Where you find this screw, the designer wanted a fastener that could be done up firmly and undone years later without drama.

Flat head and hex head are not interchangeable even though the thread and the length are identical. A flat head is designed to pull down into a countersunk hole and finish flush; a hex head sits proud on a flat face. Put a hex head into a countersink and it will not seat — it perches on the chamfer and the joint is loose from the first day. Put a flat head where a hex head belongs and you lose the driving torque the joint was designed around.

Zinc plating is the corrosion barrier, and it is thin. A screw whose plating has been scraped through by a badly fitting socket, or that shows rust spots, has lost that barrier and will corrode into its thread. On a machine that carries detergent over every fastener, that is the difference between a screw that comes out next service and one that shears.

Order by part number rather than by description. Anyone working from the parts diagram alone sees the same nominal size for both screws and has a fifty-fifty chance of getting the wrong one. If you are not sure which you have, look at the head: six flats and it is this one.

Fit with clean threads to a firm torque. #10-24 is a coarse thread in a small size and it strips readily in soft material; the hex head will let you apply far more torque than the thread can take, so stop at firm.

Browse every assembly for this machine on the Tornado 98168 Marathon 1200 parts hub, and see the manufacturer’s range at tornadovac.com.

Frequently Asked Questions

What Tornado machines does the screw 17957 fit?

It is used on the Tornado 98164 MWH-800 8-gallon self-contained extractor, the 98166 and 98167 20″ Marathon 800, the 98168 12 Gallon Self Contained extractor and the 98168 20″ Marathon 1200 in all series. Call 763-535-0770 with your model number if you are not sure.

How is 17957 different from the other #10-24 x 1/2 inch screw?

Head style and material. 17957 is a zinc-plated hex head cap screw; the other is a Phillips flat head in stainless. Same thread, same length, different part numbers, and they are not interchangeable — a hex head will not seat in a countersunk hole and a flat head loses the driving torque a hex joint was designed around.

How do I tell which one I have?

Look at the head. Six flats driven by a socket or spanner is this screw. A cross recess in a tapered head that finishes flush with the surface is the flat head stainless version under a different part number.

How do I order the Screw Hex Head Cap #10-24 x 1/2″ Zinc Plated (part# 17957) or get help?

You can add the Screw Hex Head Cap #10-24 x 1/2″ Zinc Plated (part# 17957) directly to your cart on this page, or call us at 763-535-0770. Our staff at 5415 West Broadway, Crystal, MN 55428 has been servicing Tornado equipment since 1956 and can help confirm the right part for your machine.

Questions? Call us at 763-535-0770 or visit us at 5415 West Broadway, Crystal, MN 55428.