DoubleGroove™ Close Fit Tall Dogs
Innovative 20mm bench dogs ideal for positioning guide rails or jigs to your perforated worktop
This product is a special "Close Fit" version of our general purpose DoubleGroove™ Tall Dog. Most 20mm dogs on the market feature a 19.90mm body, which fits well in the Festool MFT/3 but can result in needless play when used with the Parf Guide System or a 20mm worktop made with precision by CNC router. Instead, our "Close Fit" or CF-Dogs feature a 19.98mm body providing a near zero clearance fit when inserted into a 20mm bench dog hole.
The usefulness of DoubleGroove™ CF-Dogs isn't limited to those using the Parf Guide System. Many woodworkers are creating custom 20mm tops with CNC routers capable of machining holes accurate down to ±0.002" (0.050mm). With this kind of accuracy, many discover that their traditional 20mm bench dogs now fit with unwanted play; a problem that can be solved with DoubleGroove™ CF-Dogs.
For more information on our CF-Dogs, read the DoubleGroove™ CF-Dogs Small product page. The remainder of this page is taken from our standard DoubleGroove™ Tall product page.
We've reinvented the modern 20mm bench dog and, in the process, addressed some common frustrations. Having dealt with our fair share of ill-fitting or "stuck" dogs, we've designed our dogs with twin grooves that run around the collar. While it may not seem like much, these double grooves make it much easier to remove the dog once it has been installed. Sharing the same careful attention to detail that has set our precision tools apart, small but important design elements—like the tiny undercut beneath the collar that guarantees a perfect 90 degree transition, even if the holes in your work surface aren't perfectly free of tearout, or slight chamfers along the touchable surfaces—result in a tool that's comfortable, accurate and a pleasure to use.
DoubleGroove™ Tall Dogs measure 70mm above the collar, and 18mm below the collar. This makes them the perfect size for positioning your guide rail, when used in combination with Dog Rail Clips. A unique design element—an easy-on taper at the top of each Tall Dog—simplifies the process of attaching your guide rail. (See the video below for a depiction of this process.) To accommodate clamping, an included M8x1.25 threaded hole at the bottom of each dog accepts our M8 SpeedKnobs™, FESTOOL® M8 knobs from the clamping elements kit, or any other similar off-the-shelf M8x1.25 threaded knob. All DoubleGroove Dogs are made in the USA from 6061-T6 aluminum on high-precision CNC machining centers and clear anodized for maximum durability. Sold in pairs.
The DoubleGroove™ Dog family includes a variety of sizes: Small (ideal for most general use applications), Medium (for use with our PTR-18 Precision Triangle or thicker work surfaces), Large (for use with our MTR-18 Precision System Triangle), Tall (for using in conjunction with Dog Rail Clips to secure your guide rail to your worktop), and Stubby (also designed for use with Dog Rail Clips, but with a shorter height to clear your track saw motor housing when plunge cutting). Additionally, specialized "Close Fit" versions of our Small, Large, Tall (the product on this page), and Stubby Dogs are available for those who want a tighter fit in 20mm worktops made with precision tools (e.g. CNC router or the Parf Guide System).
- Easier to Use: Twin grooves running around the collar make DoubleGroove Dogs easier to remove than other dogs on the market; no more stuck dogs!
- Optimized for Guide Rails: DoubleGroove™ Tall Dogs feature an easy-on taper designed into the top, which simplifies the process of connecting your guide rail to the worktop.
- A Perfect Fit: Precision machined to exacting tolerances, with a diameter of 19.9mm to strike the perfect balance between solid, secure mounting and ease of insertion/removal.
- Ideal for Custom Worktops: If you've made your own 20mm worktop based on the 20x96mm standard and aren't quite sure if your tolerances are perfect, you'll likely find DoubleGroove Dogs to be a better choice. Their twin collar grooves will make it easier to remove dogs that might become "too snug," and a swept undercut along the collar means DoubleGroove Dogs will mount flush even if your holes have tearout.
- Clampable: Each dog includes an M8x1.25 threaded hole, perfect for use with our SpeedKnobs to secure the dogs inside your 20mm worktop. (If you already have the knobs from Festool's 488030 Clamping Elements, those will work too, but you'll find our SpeedKnobs to be much faster and easier to thread.)
- Material: 6000 series aluminum alloy, T5 tempered and anodized clear
- TSO Products SpeedKnobs™
- Dog Rail Clips, for use in combination with DoubleGroove™ Tall Dogs to attach your guide rail to your worktop
See DoubleGroove™ Dogs In Action!
Additional Photos & Applications
DoubleGroove Dogs™ can be used to secure your workpiece to your perforated worktop at perfect 90 or 45 degree angles. When used in conjunction with Dog Rail Clips, our dogs can also be used to secure your guide rail to your worktop.
DoubleGroove™ Dogs will be a snug fit in your perforated worktop, but if you need an extra degree of security, all of our dogs feature an M8x1.25 threaded hole accepting TSO SpeedKnobs™ (our preferred, super quality M8 knob), FESTOOL® clamping elements knobs, or off-the-shelf knobs with M8x1.25 threads.(DoubleGroove Tall Dog shown in the picture above.)
Part of a complete range of 20mm workholding accessories from TSO Products!
Got a suggestion to make this page even better? Your feedback and suggestions are always welcome!
Other DetailsTSO brand products are guaranteed for five years from date of sale against defects in materials or workmanship. Normal wear and tear and accidental damage are not covered. For any product determined to have a defect covered by this warranty, TSO Products will repair or, at its option, replace with current comparable product. Warranty requests require an RMA (return authorization number) prior to any return. Request an RMA number by contacting TSO Customer Service (email@example.com).
5 Reviews Hide Reviews Show Reviews
Very nice fit. Less play. Still need knobs for a rigid fit.
My recommendation after using them - get these because of the perfect fit to the Parf 20mm holes, no slop. Get the short pair as well.
Invaluable part of my isometric mft table work. Worked like a charm with good quality. Simply elevated my wood work
Combined these with speed knobs, very pleased! Quality products, will buy from TSO again!
These close-fit dogs work well with the UJK Technology Dog Rail Clips in a Paulk "FastCap" workbench. Be advised, the bench top is 1/2" ply so the dogs extend slightly below the top. For that reason, you can't lock them in place unless you use some sort of washer. They fit tightly enough that I haven't needed to do that.