Outsourced Grinding for Machine Shops & Contract Manufacturers

You take the job. We hold the tolerance. Your customer never hears our name.

Why Shops Send Grinding Out

Nearly half our work comes from other manufacturers: contract machining houses, job shops, tool and die shops, and other grinding shops. Every one of them reached the same point. A print came in with a diameter tolerance, a roundness callout, or a finish spec their equipment could not hold repeatably. The choice was to buy a grinder, no-quote the job, or send it out.

We are the third option.

From One-Off Overflow to Standing Production

When Sending It Out Makes Sense

The print calls for tighter than 0.001 inch on a diameter and your turning centers are fighting it.
You need a finish under 16 Ra and someone is polishing by hand to get there.
Roundness or cylindricity is called out and you have no repeatable way to hold it.
Heat treat moved the part and it now has to be ground back to size.
You have the capability but not the capacity, and the ship date is next week.
One part in a family needs grinding and tooling up for that one part makes no sense.
The material is Inconel, Hastelloy, Monel, A286, or titanium and nobody in the building wants to put it on a machine.

Materials We Run

Most of the work shops send us is conventional: hardened and case-hardened steel, chrome-plated rod, tool steel, 300 series stainless, cast iron, powder metal, and engineering plastics. That is the bread and butter, and it ships every day.

We also run nickel and high-temperature alloys — as production work, not as favors. These materials fight back: they work-harden the moment the wheel dwells, they conduct heat poorly so the heat goes into your part instead of the chip, and they load wheels fast on dress schedules that work fine on 4140. When a print like that shows up and nobody in your building wants to touch it, send it to us. The alloys we run:

Nickel alloys: Inconel 625 and 718, Hastelloy, Monel, Incoloy
Iron-nickel: A286
Titanium and PH stainless: 17-4 PH, 15-5 PH, Ti-6Al-4V

We quote superalloy work at the cycle times it actually takes and the wheel cost it actually carries. You get one number up front instead of a low quote followed by a conversation about how difficult the job turned out to be.

Capabilities at a Glance

Process	Capacity	Diameter tolerance	Finish	Machines
CNC OD grinding, straight and angle head	6 in dia x 36 in length	0.0002 in (lengths to 0.0006 in)	8 Ra	12
Semi-automatic cylindrical and universal OD	6 in dia x 60 in length	0.0002 in	8 Ra	6
Centerless, thru-feed and infeed plunge	0.125 to 4 in dia	0.0001 in, roundness < 0.0001 in	8 Ra	10
ID grinding	6 in dia x 8 in length	0.0002 in	8 Ra	2
Precision honing	0.087 to 2.0 in dia, 6.6 in max length	0.0002 in	8 Ra	10
Surface grinding, Blanchard rotary	30 in	0.0005 in width	32 Ra	1
Surface grinding, reciprocating	16 in x 32 in	0.0002 in width	8 Ra	1
Hard turning	10 in dia x 16 in length	—	—	2

How We Work With Shops

We quote from your print. Send a PDF through the RFQ form and you will hear back with a price. Every order is acknowledged with a ship date.
We grind to your print and your inspection requirements, under a documented ISO 9001:2015 quality system.
We ship back to you, not to your customer. Your packing slip and your box if that is how you want it handled.
We sign NDAs, and we sign them routinely.
We do not solicit your customers. Not now, not later. Several of these relationships have run more than fifteen years and that is why.

Part type: Spindle Shaft – OD Grinding & ID Grinding

Industries: Agriculture, Auto/Transportation, Oil & Gas Services, Recreational Vehicle/Power Sports

Applications: Shafts used in any industry with a moving part

Part type: Spindle Shaft – OD and ID Grinding

Industries: Agriculture, Auto/Transportation, Oil & Gas Services, Recreational Vehicle/Power Sports

Applications: Shafts used in any industry with a moving part

Part type: Diesel fuel injection barrel- Honing

Industries: Agriculture, Building/Construction Equipment, Military/Defense Equipment

Applications: Diesel fuel injector barrel honing is a precision machining process used to create or restore the precise inner diameter and surface finish of fuel injector barrels.

Part type: Boom Roller – OD Grinding and ID Grinding

Industries: Building/Construction Equipment

Applications: Boom trucks are versatile, truck-mounted cranes used for lifting and transporting materials, particularly in construction and utility applications.

What Our Customers Say

"Custom Production Grinding has been a valued partner in our supply chain for more than 15 years. They always deliver a quality product at a reasonable price in a timely manner. The staff is knowledgeable, dedicated and always willing to help us out of what is seemingly some hard-to-meet deadline requests. I would recommend Custom Production Grinding to anyone looking to have grinding done to a job. In my mind, they are second to none."

"Thank you and your team for the quick turnaround on the shaft project. I had a lot of pressure on getting these completed, with it being such a high-profile project for us, and of course by the time you got the parts there was no time to spare. Somehow I always worry, but somehow you guys always come through for me! In times like this it reminds me why I consider you a partner vs. just another one of my suppliers."

"I have been using CPG for more than 20 years for my grinding needs. I have always been very satisfied with their professionalism, quality and attention to detail. They truly have a sense of urgency when it comes to servicing each job. They will go above and beyond to get the job done when we need it, and they are one of the most competitively priced grinders in southeastern Wisconsin. I would recommend them for any grinding projects – whether it’s a small quantity, or large production run."

"I’ve been in supply chain management more than 30 years and am pleased to share that Custom Production Grinding is by far one of the most outstanding vendors I have worked with to date. Their staff is extremely easy to work with and does their utmost to achieve our sometimes unreasonable goals; it could be a move-up in a delivery promise, a same-day quote request, an explanation of said quote, or collaboration on a difficult solution or corrective action. I would gladly recommend their organization for your production grinding needs."

"CPG has been grinding our parts since the start of our company in 1997. They have earned our business and trust over the decades. The quality we received from them has been second to none and we know they will grind the job right. Their staff has a great understanding of our products and guide us in ways to produce our parts to help cut costs in the grinding process. We have been in rush situations with no time to go through the quoting process and just sent them the parts to be ground. Because of their integrity, we know we will be treated fairly. They are a great partner to us."

"We’ve worked with CPG for more than 15 years. They are a trusted partner in exceeding our customers' expectations!"

"We have been doing business with CPG for over 38 years. They have been a strategic part of our supply chain since they opened. They are easy to work with and extremely accommodating to our due dates, with quick turnaround times. They produce quality parts and have great attention to detail."

Start With One Job

Send one part. One piece, ten, or a thousand. We quote prototype and short run alongside production work. The point of a first job is for you to find out whether the parts come back right, and whether they come back on the day we said they would.

Let’s Talk About Your Specific Requirements