20"
The outer diameter of the disks for this chuck is 19.375"

Longworth vs. Doughnut

Frequently Asked Questions
1) Question Which one is better, Longworth or Doughnut?

Answer) It depends on the shape of the vessel. For traditional smaller bowls & plates, the Longworth Style is more self-centering and a bit faster to set up. You still have to use the tailstock for extra support until you get down to the last 1” or so.

Answer) For larger plates, platters or bowls, the doughnut chuck provides a more secure hold. You have to take care to make sure the vessel is centered and setup takes a bit longer.

Answer) For vessels which are more vases like (taller rather than shorter) the doughnut chuck is a clear winner.

2) Question What is the difference between a Type 1 Longworth and a Type 2 Longworth Chuck?

Answer) Type 1 has been on the market for almost 10 years and has gained worldwide acceptance. It uses the traditional configuration, but is equipped with a steel mounting disk on the back designed to be held in the jaws of a 4 Jaw woodworking scroll chuck. Both disks in a Type 1 Longworth Chuck are .25” phenolic with a 1/8” disk of UHMW plastic (Ultra High Molecular Weight) sandwiched in between to reduce friction. This isn’t needed with HDPE plastic.

Answer) The Type 2 Longworth Chuck is different in 3 major areas:

i) The disks are ½” HDPE (high density polyethylene) and there is no UHMU layer needed.

ii) The Type 2 is equipped with a threaded faceplate and threads directly onto the lathe spindle.

iii) An OPTIONAL accessory is a set of Doughnut rings for use with the Type 2 Longworth Style Chuck only. The Type 2 chuck may be used in the traditional Longworth scrolling mode or as a traditional Doughnut Chuck with doughnut rings.

DOUGHNUT RINGS CANNOT BE USED WITH A TYPE 1 LONGWORTH CHUCK. IT IS DANGEROUS AS THE PHENOLIC WILL LIKELY CRACK WHEN THE BOLTS ARE TIGHTENED.

3) Question What are the thread sizes for the faceplates?

Answer) Both the 10” and the 12” Longworth Type 2 chucks come with a 1” x 8 tpi faceplate suitable for lathes able to swing up to 14” in diameter.

Answer) The 16” Longworth Type 2 comes with a 1-1/4” x 8 tpi faceplate commonly found on lathes able to swing 16” and larger.

Answer) I will offer M33x3.5 option for an extra charge. These will be special orders and require additional manufacturing time.

4) Question If I already have a Longworth Chuck Type 1, do I need the type 2?

Answer) Only if you turn items where the tailstock can’t be used. You should probably be using the Amazing Doughnut Chuck™.

5) Question If I already have an Amazing Doughnut Chuck™ but want a Longworth?

Answer) The Longworth Chuck Type 2 is directly compatible with ALL of the doughnut rings which came with your Amazing Doughnut Chuck™. That includes the top plate, the big hole top plate and all rings in the notched ring set. This is true for the 10”, 12” and 16” sizes. Note: The Amazing Doughnut Chuck™ HDPE parts are yellow while the Longworth Type 2 are black HDPE.

6) Question Is the Longworth Type 1 Chuck still available?

Answer) Yes, absolutely. We have no plans to discontinue the Type 1 version made of phenolic intended to be held by a regular 4 jaw scroll chuck. This is a similar, but different product.

7) Question Can I use the Longworth Type 2 in Longworth Mode and Doughnut Chuck mode together both at the same time?

Answer) YES! I have redesigned the Longworth Type 2 so both modes can be used simultaneously.

8) Question If I decide to get just a Longworth Chuck Type 2 without the doughnut ring option, can I get the rings later?

Answer) Yes, the doughnut rings are always available alone or in sets apart from the Longworth Type 2 or apart from the Amazing Doughnut Chuck™.

9) Question What is included in the optional Doughnut Ring Upgrade for the Longworth Type 2?

Answer) For the 10” and 12” sizes there is a doughnut ring with a 6” opening and a smaller ring with a 4” opening. Hardware includes 4” and 8” bolts 3/8” x 16 tpi, 4 tightening knobs and washers. That size bolt is readily available in many different lengths at hardware stores and box stores.

Answer) For the 16” size Longworth Type 2 chuck you would also receive a Big Hole Top Plate with a 9” opening in addition to all of the hardware and other doughnut rings just mentioned.

10) Question What about weight?

Answer) Weight is a consideration. The entire assembly of the Longworth Type 2 in Doughnut Chuck mode is about the same as a bowl blank before it is turned and hollowed. If your lathe is able to turn that much weight efficiently, you shouldn’t have any problem with the weight of the Longworth Type 2 assembly.

11) Question Are the holding capacities the same between the Longworth Type 1 and the Longworth Type 2?

Answer) They are very similar but not exactly the same. The minimum diameter is a bit smaller with the Longworth Type 2 because the faceplate is usually smaller than a four jaw chuck used to hold the Longworth Type 1. The Maximum holding diameter is almost the same for both types.

12) Question Are the combo packs less expensive than if I get them individually?

Answer) All manufacturers offer a discounted package prices due to manufacturing efficiencies.