Tornado Screw Hex Head Cap 1/4-20 x 1/2″ Stainless 19240

This is the hex head, stainless 1/4-20 x 1/2 inch screw. The machine also uses a zinc-plated Phillips truss head screw of identical thread and length under a different number, so order by part number rather than by size. Part number 19240 is the hex head stainless version.

Compatible Models for the Screw Hex Head Cap 1/4-20 x 1/2″ Stainless

This part is shared across a wide run of machines. On the Marathon 1200 family it is fitted to:

• 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)
• Fits many other machines — call 763-535-0770 and we will confirm fitment for your machine.

Hex head means socket or spanner rather than a driver, and that changes what the fastener can do. It can be torqued to a real figure without camming out, and it can be undone years later without the head being chewed. Where you find this screw, the joint was designed to be properly tightened.

Stainless is the second half of the specification, and on this machine it is the more important half. A plated screw in a position that sits in standing detergent eventually corrodes through its coating and seizes into the thread. Stainless costs more and it is the reason the fastener is still removable in five years.

The stainless trade-off is galling. Stainless on stainless can cold-weld under load, particularly if a fastener is run down fast with a power driver, and a galled screw seizes solid part way in with no way forward or back. Run it in by hand until the head is close, then tighten. If it binds unexpectedly, back it out and clean the thread rather than forcing it.

Do not mix stainless and plated fasteners in the same joint where you can avoid it. Dissimilar metals in a wet, detergent-rich environment corrode galvanically at the junction and the softer one loses.

Fit with clean threads to a firm torque. The hex head will let you apply far more than 1/4-20 can take, so let the joint rather than the tool decide.

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 machines does the screw 19240 fit?

It is fitted to the Tornado 98168 12 Gallon Self Contained carpet extractor and the 98168 20″ Marathon 1200 in all series, and it is shared across many other machines. Call 763-535-0770 with your model and serial number and we will confirm fitment before you order.

How is 19240 different from the other 1/4-20 x 1/2 inch screw?

Head style and material. 19240 is a stainless hex head cap screw driven by a socket or spanner; the other is a zinc-plated Phillips truss head with a wide, low dome. Same thread and length, different part numbers, chosen for different jobs.

My stainless screw seized part way in — what happened?

Galling. Stainless on stainless can cold-weld under load, especially when a fastener is run down fast with a power driver, and the screw then seizes solid with no way forward or back. Run it in by hand until the head is close, then tighten, and if it binds unexpectedly back it out and clean the thread rather than forcing it.

How do I order the Screw Hex Head Cap 1/4-20 x 1/2″ Stainless (part# 19240) or get help?

You can add the Screw Hex Head Cap 1/4-20 x 1/2″ Stainless (part# 19240) 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.