JOMA Style Blade Fitment: Bolt Patterns, Sizes, and Mounting Hardware

JOMA style blades are manufactured with standard AASHTO bolt patterns — typically 12-inch or 8-inch on-center — which makes them a direct-fit replacement for existing JOMA style setups on major plow brands. You keep your current clamping bars and Grade 8 mounting hardware; the composite blade sections are what you replace. This guide explains the fit details, the standard sizes, and how custom sections work. The JOMA style blade product page lists the standard sections and dimensions.

AASHTO Bolt Patterns Explained (8″ and 12″)

The bolt pattern is the hole spacing that mounts the cutting edge section to the plow. AASHTO standards define the common patterns used across North American plow brands, and JOMA style sections are drilled to match. The standard spacing convention for snowplow cutting edges has existed for decades — the AASHO committee on uniform hole punching recommended standard hole spacing for snowplow cutting edges back in the 1960s, and today’s 8-inch and 12-inch on-center patterns descend from that standard. Before ordering, measure the hole spacing on your current section (center to center) and confirm it matches.

Transportation research reinforces why fitment discipline matters: NCHRP Project 06-19 on snowplow cutting edges found that how a blade is specified — dimensions, hole pattern, material, and quality controls — determines whether an agency can compare blades and change suppliers without re-engineering the plow. A blade that does not match the spec is not a “similar product”; it is a different product.

3-Foot vs 4-Foot Sections

SENTHAI stocks the two standard JOMA style section sizes used by North American fleets: 3-foot and 4-foot sections. The 4-foot section measures 48″ x 6″ x 7/8″ (1219mm x 152mm x 23mm) and weighs 17.5 kg; the 3-foot section measures 36″ x 6″ x 7/8″ (914mm x 152mm x 23mm) and weighs 13.1 kg. Match the section length to your existing setup — mixing lengths across a plow creates uneven wear and inconsistent scraping.

What You Keep vs What You Replace

JOMA style blades replace the cutting edge sections only. You keep your existing clamping bars, mounting hardware, and plow frame. Hardware should be Grade 8 for the mounting application — SENTHAI supplies the composite sections, and your existing clamping system does the clamping. This is what makes the switch a direct-fit changeout rather than a plow conversion, and it keeps the replacement cost low.

Custom Sizes from Drawings and Samples

If your equipment uses a non-standard section, SENTHAI manufactures custom JOMA style blades to your drawings, samples, or specifications. Custom work covers unusual lengths, hole patterns, thicknesses, and even specialized rubber or carbide configurations. Send the drawing or sample, and the engineering team confirms the production profile before quoting.

Fitment Checklist

• Measure the hole spacing of your current section (center to center) and confirm 8-inch or 12-inch on-center.
• Confirm section length (3-foot or 4-foot) and match all sections on the plow.
• Verify the thickness profile (7/8″ standard) clears your clamping bar.
• Keep existing clamping bars and use Grade 8 mounting hardware.
• For non-standard patterns, request a custom section from a drawing or sample.

Ordering Checklist: What to Send the Supplier

To get a confirmed fit on the first try, send five things: the hole spacing measured center-to-center, the section length, the thickness profile, a photo of the current section and clamping bar, and the plow brand and model if known. For custom work, add a drawing or sample. These inputs let the engineering team confirm the AASHTO pattern and section dimensions before quoting.

Mistakes are expensive in winter, so measure twice: a section with the wrong hole pattern cannot be field-drilled without weakening the steel, and a mismatched length creates uneven wear. Confirming fit before ordering — the process described on the SENTHAI JOMA style blade collection page — is what makes the changeout a same-day swap instead of a return.

Frequently Asked Questions

Will JOMA style blades fit my plow brand?

If your plow uses a standard AASHTO bolt pattern (8-inch or 12-inch on-center), JOMA style sections are a direct-fit replacement. Confirm the pattern before ordering.

Do I need new clamping bars or hardware?

No. You keep your existing clamping bars and use Grade 8 mounting hardware — only the blade sections are replaced.

Can I get a custom length for a non-standard plow?

Yes. SENTHAI manufactures custom JOMA style blades from your drawings, samples, or specifications.

Should I mix 3-foot and 4-foot sections on one plow?

No — mixing section lengths creates uneven wear and inconsistent scraping. Match all sections to your plow width.