SMW Fixture Plates

What are the benefits to using a modular fixture plate on a CNC machine?
  • Increasing the workholding, clamping and setup area
  • Convenience of having hundreds of bored and tapped holes versus a few t-slots
  • Indexing, shifting, locating and holding large parts
  • Clamping large parts outside of the machining envelope
  • Using the SMW Mod Vise low profile, modular work holding system!
  • Protecting the CNC machine table (often made from soft cast iron)
  • Quickly aligning, tramming, and clamping vises and other workholding
  • Using custom, hot-swappable fixture plates tops (i.e. pallets)
Should I buy an aluminum or steel fixture plate?
  • Steel plate benefits: machined from 4140 alloy steel, these are our premier line of fixture plates. The high quality, semi-hardened (26-30 HRC) alloy steel means these fixture plates are the strongest and toughest, well suited for daily use.
  • Aluminum plate benefits: lower price and lighter weight means reduced shipping cost and easier installation.
    •  7075 Anodized Aluminum fixture plates are an excellent mix of value, weight, and strength. 7075 aluminum has nearly twice the tensile strength as 6061. The anodized surface increases wear resistance, helps reduce scratches, and offers galvanic corrosion resistance. Threaded holes are form tapped for maximum strength.
    • 6061 Aluminum fixture plates are our value line offering. We take pride in the manufacturing process and tolerances of these plates and they are a great way to increase the workholding envelope, implement the SMW mod vise system, and minimize setup time on your CNC machine! Threaded holes are form tapped for maximum strength. NOTE: when these plates are installed on a non-aluminum surface such as a bare machine table these plates must be used with a galvanic corrosion inhibitor (e.g. dielectric spark plug grease) and be removed frequently to inspect for condition and/or re-apply the corrosion inhibitor. Corrosion inhibitor is available for purchase here.
What are the tolerances of an SMW fixture plate?


  • 1/2" SMW Fixture Plates are held to parallelism of 0.0005" per 18" of plate length (+/- 0.00025") across a single plate.
  • 1/4" and M6 fixture plates are held to a parallelism of 0.001" [0.025mm] across the entire plate.

Matched Plate Set Tolerances

  • For sets of 2 plates, the parallelism tolerance of the set is identical to that of a single plate (0.0005" per 18"). 
  • For matched sets of 3+ plates, thickness at the plate seams is matched within 0.0005". Each plate is then individually subject to the standard parallelism tolerance (i.e. each plate in the set will be parallel within 0.0005" per 18" of length and have a thickness variation of no more than 0.0005" at the edges where plates meet).
  • The continuity of the fixturing hole pattern across multiple plates is dependent on careful setup of the plates. These sets have a small gap (~0.008") designed between fixture plates, allowing for some adjustment of the hole pattern alignment. We recommend using our Fixture Plate Set Alignment Jig for installation of these fixture plate sets.


We do not qualify plates in an unconstrained state. However, we do evaluate and process the raw material in a specific way so that when the fixture plate is secured to the machine table, it's "flatness" will be the result of the parallelism tolerance plus any deviation, level, or tram error in the machine table. 

Thickness Tolerance

  • We prioritize parallelism over the final thickness of the fixture plate. In general, thickness may vary +0.01" [0.25mm] -0.04" [1.02mm] from the nominal value given. This does not mean the plate will have 0.05" [1.3mm] variation in the thickness.
  • For example, the measured thickness of our standard 0.950" nominal plates may come out at 0.930". Each point measured along the plate will be within +/- 0.00025" of this 0.930" dimension (the parallelism tolerance).
  • Some fixture plates, such as those sold individually but intended for use as a set (e.g. Shapeoko 4, Tormach 24R) are subject to a tighter thickness tolerance so that plates can be purchased and used interchangeably. See product drawings for these tolerances.

Bore Tolerances

The 1/2" precision bores on the SMW fixture plates are machined to 0.5005" +/- 0.0002".  We have found this to be the ideal tolerance when using a mix of dowel pins, gauge pins and accessories like the SMW Mod Vise.  Keep in mind, for a dowel pin to have a "slip" fit (e.g. not require hand tools, vice grips, etc. to remove), there must be some gap or "slop" in the fit between the pin and the hole.   
What is the hole spacing on an SMW fixture plate?
  • Standard 1/2" SMW Fixture Plates have a hole spacing of 1.250" on-center. These plates have our double offset pattern (an additional hole pattern on the same spacing occurs between the first pattern, giving you more fixturing holes).
  • 1/4" SMW Fixture Plates have a hole spacing of 0.750" on-center. Not all 1/4" plates have our double offset pattern.
  • M6 SMW Fixture Plates have a hole spacing of 20mm on-center. Not all M6 plates have our double offset pattern.
Is each hole bored and threaded?
  • On standard 1/2" SMW Fixture Plates each hole is precision bored approximately 0.25" deep for use with a 1/2" dowel pin, the SMW Mod Vise or other 1/2" accessories. Below the precision 1/2" bore each hole is tapped 1/2"-13 UNC.
  • On standard 1/4" SMW Fixture Plates each hole is tapped 1/4"-20 UNC. Most 1/4" x20 plates do not have bores, instead we recommend our 1/4" Fixturing Pin.
  • On standard M6 SMW Fixture Plates each hole is tapped M6x1.00. Most M6 plates do not have bores.
What if a dowel pin has a loose fit?
Dowel pins can be purchased with varying degrees of tolerance and fit, but traditional "off the shelf" dowel pins (e.g. this 1/2" dowel pin from McMaster Carr) have dimensional tolerance of 1/2" +0.0001 to +0.0003.  A pin cannot fit in a hole of the same size; the hole must be larger.  Our hole tolerance, as described above, allows for this fit.   However, adding a relatively small amount to a bore diameter - even 0.0001" results in a notable difference in the feel and fit of how a pin fits into a hole.  We use a combination of metrology tools, including bore gages and deltronics gage pins, to ensure bores meet our tolerances. 
What is the appropriate torque spec for my fixture plate?
When installing your plate we recommend 60 ft-lb (81 N-m) for the low-profile SHCS that secure the fixture plate to the T-Nuts. NOTE: This value is only for our standard 1/2-13 UNC low-profile SHCS which are common on most Tormach and Haas fixture plates. Please verify the maximum acceptable torque for bolts and mounting hardware of other sizes. 

When using the plate the appropriate torque for workholding depends on a variety of factors, including the thread engagement of the stud or screw into the fixture plate.  Below assumes 1X diameter thread engagement (e.g. 0.500" for a 1/2-13 bolt, keeping in mind that that top 1/4" of the plate is not threaded)
  • For the 1/2"-13 holes in aluminum plates, we recommend up to 45 ft-lb or 61 N-m.  DO NOT exceed 50 ft-lb or 68 N-m.  
  • For the 1/2"-13 holes in steel plates, we recommend up to 50 ft-lb or 68 N-m. Do not exceed 70 ft-lb (94 N-m).  
  • For 1/4-20 holes in aluminum plates, we recommend 75 in-lbs (do not exceed 110 in-lbs) 
  • For M6 holes in aluminum plates, we recommend 69 in-lbs (do not exceed 100 in-lbs)
Are solid models provided?
Yes, solid models and product drawings are available for download on their respective product pages. For legacy products no longer listed, see our Legacy Products page.
Will you machine a custom plate for my machine?
Yes, please contact us via this form
How do I set up and install my SMW fixture plate?
How do I prevent rust on my steel fixture plate?
What maintenance do I need to do on my fixture plate?
We recommend any workholding device (fixture plate, vice, 4th axis, etc.) be periodically removed and cleaned.  This interval depends on personal preference, frequency of use, types of material being cut, coolant and more but generally should be inspected every 3-12 months.  See FAQ item above for tips on preventing rust. 
What is the lead time for fixture plates? Are they kept in stock?
Generally, fixture plates are kept in stock and ship within 1-2 business days. Inventory and lead time (if out of stock) can be seen on the product page for the specific plate you would like to purchase.

Please contact us to confirm inventory or to inquire about time-sensitive orders.
What are the plates listed as "used", "blem", "old stock", etc.?

  • Occasionally (albeit infrequently) "used" plates will be added to the store at a discount. These plates are still functional but have been previously installed (typically used in the SMW shop) and may have slight cosmetic defects.
  • "Blem" (i.e. blemished) or scratch-and-dent fixture plates are discounted plates with minor functional or cosmetic defects.
  • "Old Stock" plates are typically discounted due to a slight revision in that specific product but are like-new.
Each plate listed will include further details on its product page. Our current scratch-and-dent inventory can be seen here.

Orders on blem, used, old-stock, or otherwise discounted fixture plates are final, non-cancellable, and non-returnable. If you have questions about a specific plate, please reach out to us before purchase.

Modular Vise System

How do I use the SMW Modular Vise System?

Gen3 Vises:

Gen2 Vises:

What are the recommended torque specs for the Mod Vise?

Gen21/2"Varies depending on fixture plate material and hole pattern. See our Fixture Plate FAQ.10-30 ft-lbs* [14-40 N-m]35 ft-lbs [47 N-m]
Gen21/4"Varies depending on fixture plate material and hole pattern. See our Fixture Plate FAQ.10-25 ft-lbs* [14-34 N-m]30 ft-lbs [40 N-m]
Gen2M6Varies depending on fixture plate material and hole pattern. See our Fixture Plate FAQ.10-25 ft-lbs* [14-34 N-m]30 ft-lbs [40 N-m]
Gen31/2"Varies depending on fixture plate material and hole pattern. See our Fixture Plate FAQ.10-30 ft-lbs [27-40 N-m]35 ft-lbs [47 N-m]
Gen3M12Varies depending on fixture plate material and hole pattern. See our Fixture Plate FAQ.10-30 ft-lbs [27-40 N-m]35 ft-lbs [47 N-m]
*On Gen2 vises, clamping torque is dependent on a) the use case and needed clamping force and b) how much the jaw is 'preloaded' (i.e. how far the two clamping screws are backed out before setting the position of the adjustable base). As long as Gen3 vise clamping screws are fully backed out (2+ turns) when preloading, clamping force is only dependent on the bolt torque. As a general rule, 20 ft-lbs [27 N-m] is acceptable for most use-cases with all versions of the SMW Modular Vise.

How does the Modular Vise work?

The Mod Vise uses tapered clamping screws to apply clamping force to the part. These screws transfer the downward force created by the screws into horizontal force pushing the vise jaw into the part.


How do I know if I have a Gen2 or Gen3 Modular Vise?

Gen3 vise sales commenced in early 2024. Vises ordered before this date are Gen2. If unsure, please see the graphic below for determining which generation your SMW Modular Vise is. (Aluminum 'Hobby' vises are currently Gen2 only.)
What is the difference between the Gen2 and Gen3 Modular Vise?

The Gen3 Mod Vise changes include:

  • Jaw Insert Bars are now included with every Gen3 vise! Castle Grips are available as an add-on (and do not replace the insert bars if selected)
  • Gen3 vises use tighter tolerance, precision ground pins press-fit into the fixed-side base.
  • M12 clamping bolts provide slightly more clamping force.
  • Moving-side tapered washers have been redesigned for easier setup and use (making it more difficult to install and use them in the wrong orientation)
  • Revised top jaw slot size for easier setup of the adjustable-side base
  • Increased part density with new, slimmer dual station vise
  • The Gen3 vises also use metric hardware (not withstanding 1/2" x 13 bolts to secure to an "inch" fixture plate).  Using metric hardware makes it easier to source hardware both in the USA and, well, everywhere else in the world that uses metric.

Gen3 vises can be used alongside Gen2 vises. The jaw height and the distance from alignment pins to the jaw face are the same on both vises allowing Gen2 and Gen3 vises to be used side-by-side. 

Individual parts are not cross-compatible, e.g. a Gen2 soft jaw will not fit a Gen3 vise base. Both vises have the same jaw features, so reversible insert bars, Talon/Castle Grips, etc. remain compatible with both (note that Gen3 vises use an M5 jaw fastener instead of 10-32).

What is the Castle Grip / Turret Grip?

The Castle Grip is a low-profile, aggressive clamp designed to complement the Modular Vise System.  The Castle Grip is best suited for Op1 workholding where the user wants to maximize grip by allowing the Castle Grip teeth to ‘bite’ into the material. 

Turret Grips are similar to Castle Grips, but are intended for clamping round material.  

The low profile nature minimizes the amount of material being clamped, thus maximizing the amount of sidewall material available for machining.  

SMW Castle Grips are paired with Torx-plus fasteners.  This avoids a common problem with smaller size hex head screws where the hex head can be stripped.   

The recommended max torque spec for the M5 Torx screw is 35 in-lbs [4.0 N-m]. (This also applies to both steel and aluminum jaws as well as Castle Grips used with Gen2 vises having 10-32 Torx fasteners.)  We discourage hand-tightening these screws (use a torque wrench!)

Similar clamps are made by other manufacturers (and may be cross-compatible with SMW mod vise).  Note: many other clamps use hex (not Torx) screws; SMW advises only using Torx fasteners.

Castle Grips are generally not suitable for clamping on otherwise finished parts, as the teeth mar the material.  For finishing work or any work where the user wants a traditional “smooth” vise jaw, consider using the smooth insert bar included with Gen3 Mod Vises.

Do you recommend the Reversible Jaw Insert Bars, Castle Grips, or Talon Grips for the Modular Vise?

Each of our Accessory Kits include both the Castle Grip and insert bars, which is our recommendation for the most versatile setup.

If you're only purchasing one or the other we typically recommend our Mod Vise users towards the insert bar. This is because the Castle Grip leaves visible indentations into the part and aren't always suitable for Op2/finishing workholding.

This 'bite' into the part does mean that the Castle Grip can better resist vertical forces, making them a great option for large plate work or situations where the lower-profile clamping is desired. Desktop and hobby machines (e.g. using our 1/4" or M6 Mod Vise) typically don't see cutting forces high enough to necessitate the Castle Grip, although we still recommend them in cases where low profile clamping is desired. 

How can I convert my single station vise to a dual station?

The following parts lists will allow you to convert your single station vise to a dual station.

Note: parts that are size specific are noted as such (e.g. 1/4" or M6, 1/2" or M12). If not noted, parts are identical between the metric and inch vises.

Will the Mod Vise work without a fixture plate or with a non-SMW fixture plate?
Our Modular Vise System requires our standard fixture plate hole patterns - for example, 1/2"-13 tapped and 1/2" bored holes on 1.25" centers. Generally speaking, the Mod Vise will not work on non-SMW fixture plates.

PuckChuck Zero Point System

What is a Zero Point system?

A Zero Point system is a workholding system that focuses on repeatable and accurate location of workpieces, pallets, or fixtures. The name comes from the idea that you can set your WCS off of the clamping receivers and never need to change your 'zero point'. In general Zero Point systems also allow for drastically reducing setup time.
What are the benefits of using a Zero Point system?
Fixtures and pallets can be machined on the Zero Point receivers, meaning you can set your WCS once and never need to change your 'zero point'. 

Setup times can be drastically reduced:
  • Fixture and setup work can be moved out of the machine, allowing this work to happen while the machine is running other parts.
  • Much faster clamp and unclamp times, often reducing or eliminating the need for hand tools.
  • Repeatable and accurate clamping, eliminating the need for indicating, tramming, and/or probing. 
What are the key differences between the Automatic and Mechanical PuckChuck?
Automatic PuckChuck:
  • Pneumatic unclamping
  • Mechanical clamping via heavy-duty springs
  • Slighlty lower clamping force
Mechanical PuckChuck:
  • Mechanical unclamping and clamping via a screw
  • Higher clamping force
  • Same form-factor
  • Same pullstuds
In general, the Automatic and Mechanical PuckChucks can be used interchangeably. The primary difference is the clamping force and the unclamping method. With the Automatic receivers, multiple receivers can all be actuated nearly instantly with the flip of a single valve and so these are recommended for use cases with more than one receiver. Mechanical PuckChucks are great for single-receiver use cases because of their higher clamping force and the fact that actuating only a single screw is not significantly more time consuming than an air valve with a single Automatic receiver.

Discontinued Products
A repository of solid models, documentation, drawings, etc. for our legacy & discontinued products is available here.

Shipping & Returns

This covers frequent shipping questions. For a complete overview, please see our shipping policy here which supersedes all information given below.
Can I return products I ordered?
Please see our Returns, Cancellations, & Refunds policy for complete details. In general, unused products can be returned subject to a small restocking fee.

Will you ship via a carrier that is not offered on checkout?

Possibly, but per our shipping policy it is the buyers responsibility to arrange shipping once the order is ready for pickup. This includes all shipment paperwork. 
I get an error when trying to select my shipping method on checkout. What should I do?
  • For larger plates the address may be a location that our freight carrier is unable to ship to (such as overseas). Feel free to contact us to arrange other shipping methods.
  • If using autofill please verify the address is correct. Some third party payment methods (Amazon Pay, PayPal, etc.) will occasionally autofill an address that is not compatible with our store and generate an error.
  • If you are still having shipping issues on checkout, please contact us.
I would like a faster shipping method than is available on checkout, is this possible?
In some cases we can ship parcels via expedited shipping methods (e.g. FedEx Overnight), however this is not possible for all orders and is dependent on current inventory availability. Please contact us for expedited shipping inquiries. 
Can I get a faster turnaround than the published lead time for a product?
In certain situations, orders can be expedited beyond the stated lead time (for an expedite fee). See more about expedited orders on our Shipping Policy
How can I save money on shipping costs?
Shipping to a commercial address is less expensive than residential.  For freight shipments, shipping to a residential address is possible, but often significantly increases the cost due to residential shipping surcharges and lift-gate fees charged by the freight shipper.   

If possible, consider shipping to a business or commercial address with either a loading dock or forklift to reduce the shipping cost.  We can also ship to the nearest FedEx Freight terminal where the shipment can be held for customer pickup, which is an equivalent cost to shipping to a commercial address in the same area.
My package hasn’t moved on the tracking page, I think it’s lost. What should I do?
  • Please see our shipping policies page for handling lost shipments.
  • International orders may be delayed due to customs inspections or other factors outside of our control. This can cause the shipment to appear ‘stuck’ on the tracking status page.
My shipment arrived damaged, what should I do?
  • On delivery of an LTL shipment the driver will ask you to sign for delivery. Please inspect the shipment and ensure that all parts of the shipment are present before signing.  
  • Please take photos of the damaged parcel or box prior to opening.