Align boring: bores brought back onto one centerline
Align boring, also called line boring, machines two or more bores so they share a single centerline, which is what a pin or shaft needs to pass through them freely. We align bore housings, carriers, equalizer and pivot bores and gear cases at our Reno shop, and do portable align boring at your site.
- Built from your specifications, drawings or samples
- Free consultations, prompt estimates
- Wolf Machine stands behind the work we perform
- Reno shop, Monday to Friday, 7:00 am to 3:30 pm
Stock photo: a lathe rough-turning a steel shaft
A pin that has to go through three bores will only go through if the three holes are in line. Over time, wear and impact pull them apart, and a weld repair can pull them a little further. Align boring puts them back on the same axis so the machine runs as it was built.
At a glance
- Bores brought into line on one common axis
- Weld build-up first when bores are worn oversize
- Housings, carriers, equalizer and pivot bores
- Shop work here, field work on the portable page
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Why do bores walk out of line?
Pins and bearings carry load, and the load is rarely even. Material wears faster on one side, bores go oval, and a part that has been hit or heated can distort. Welding a crack closed adds heat, which can pull a bore a small distance out of position.
Once the bores are out of line, a pin binds, a bushing wears quickly and the machine develops play. You cannot fix that by replacing the bushing alone, because the bore it sits in is the problem.
How is a part set up and bored in line?
The part is measured first to find where the bores are and where they need to be. If the bores are oversize, they are built up with weld and cleaned to a surface that can be cut. The boring bar then passes through the bores on a single axis, cutting each to the same centerline and to the size that suits the new bushing or bearing.
In the shop, this is done on a horizontal boring mill or a similar machine, which holds the part still while the bar cuts. You can read about the machine on the horizontal boring and milling page.
- Measure the existing bores and mark the target centerline.
- Build up any oversize or damaged bore with weld.
- Set the part so the boring bar runs along the common axis.
- Bore each position to size on that one axis.
- Check the finished bores and fit the new bushings or pins.
Shop work or work at your site
Parts that can come off the machine are bored in the shop. A frame or a housing that is too big or too fixed to move is handled at your site with portable align boring. The guide to the signs of a machine that needs align boring helps you decide which you are facing.
What to send for a quote
Photos of the bores, the pin or bushing sizes you know, and the machine make and model get the conversation started. Attach them to the quote request or call (775) 359-5570, Monday to Friday, 7:00 am to 3:30 pm.
Sources
- Wolf Machine & Fabrication services list (2026-10-18)
- Boring (manufacturing), including line boring (2026-10-18)
Where align boring is used
- Pivot and equalizer bar bores
- Half carriers and other housings with paired bores
- Gear cases with bearing bores on a common line
- Machine frame and pivot pin bores
- Bores repaired after cracks, wear or welding
Typical parts
- Half carriers and housings
- Pivot shafts and their bores
- Equalizer bars
- Linkage and pivot bores
How to send us the job
Drawings, CAD files, sketches and photos all help. Put a ruler or tape in your photos, show the worn or broken area up close, and note any part number stamped on it.
Questions about this service
From the shop
Work from the shop
Straight answers
Align boring questions
Still have a question? Call (775) 359-5570, Monday to Friday, 7:00 am to 3:30 pm.
How do I know if my bores are out of line?
Common signs are pins that bind, bushings that wear quickly and play that returns after a new bushing. Our guide on the signs of a machine that needs align boring lists them in detail.
Can you bore oversize holes back to size?
Often, yes. The bore is built up with weld and bored back to the original size and the right centerline.
Is align boring only for large machines?
No. Any assembly with bores that must share a centerline can need it, including gear cases, pumps and plant machinery.
Send us the job
Request a quote
Tell us what you need, attach a drawing or photos of the part, and we will get back to you during shop hours. Free consultations; prompt estimates.
- From your specifications, drawings or samples. We can also assist you in designing your product or part.
- Free consultations and prompt estimates
- Stands behind the work: Our rates are very competitive and our quality is second-to-none. Wolf Machine stands behind the work we perform.
- Company accounts: all major credit cards, or we can open an account for your company
Shop hours Monday to Friday, 7:00 am to 3:30 pm. Send your request any time and we will get back to you during shop hours.
Stock photo: a lathe turning a bar, hot chips flying