Here are part counts for some of the K'NEX sets. Following the table are general comments on K'NEX pieces.

		K'NEX Set
K'NEX Piece	Description	Big Ball Factory	Giant	Explorer	Launcher	Solar Super 10	Motor Pack
	White Connector	60	65	35	6	7	-
	Blue Connector	168	60	43	10	14	-
	Yellow Connector	191	80	52	13	14	-
	Orange Tabbed Connector	39	-	6	-	-	-
	Purple Connector	331	100	51	12	8	-
	Green Connector	29	110	50	15	10	-
	Red Connector	236	65	42	12	16	-
	Light Grey Connector	24	15	12	6	12	-
	Orange Connector	114	75	22	8	16	-
	Dark Grey Connector	184	225	59	17	10	-
	Tan Wheel-Axle Connector	16	20	22	12	15	24
	Orange Chain Clip	2	-	4	2	2	-
	Rotational Connector	-	-	-	-	2	-
	Green Rod	256	250	133	32	36	-
	White Rod	332	250	125	29	21	-
	Blue Rod	587	250	111	20	23	-
	Yellow Rod	406	120	74	12	19	-
	Red Rod	23	60	48	4	12	-
	Tan Rod	2	-	4	-	-	4
	Yellow Notched Rod	-	-	4	-	-	-
	Grey (Flexible) Rod	22	20	16	4	5	-
	Black (Rigid) Rod	1	4	4	1	-	-
	Small Wheel	-	8	4	4	2	-
	Large Wheel	-	16	8	4	-	2
	Small Tire	-	8	4	4	-	-
	Medium Tire	-	6	5	2	-	-
	Large Tire	-	10	8	2	-	-
	Red Gear	6	-	3	1	1	4
	Yellow Gear	-	-	2	1	-	-
	Blue Gear	-	-	5	2	2	4
	Grey Gear	-	-	2	1	-	-
	Chain Link	132	-	40	2	2	-
	Ball	4	-	1	-	-	-
	Axle Spacer	-	-	-	36	18	-
	Hinge	-	-	-	2	-	-
	Yellow Spoked Wheel	-	-	-	4	2	-
	Electric Motor & Gear	-	-	-	-	-	Yes
	Power Pack	-	-	-	-	-	-
	Solar Cell & Motor	-	-	-	-	Yes	-
	Total	3165	1817	999	280	273	39

Naturally, some K'NEX designs are going to require parts in different proportions than what is provided in the prepackaged kits. Fortunately, several different K'NEX parts may be exchanged with each other without impacting the structural integrity or function of your design. For example, a blue connector may be used in place of a white one as long as seven or fewer rod connections are made to it. Similarly, the tabbed (orange) and untabbed (yellow) versions of the 5-rod connector are often interchangeable. In the K'NEX design books, the tabbed version seems to be used exclusively for attaching tubular flexible track. We found this track to be unruly at best, and it often requires trimming to a specific design. Consequently, we avoided its use whenever possible; for example, we created an interesting modification of the Big Ball Factory that avoided tubing altogether.

The numerous dark-grey single-rod connectors can be used as washers or spacers on axles by either clipping them on securely or merely slipping their circular ends over the rod. As well as securing a gear or a wheel to an axle, the tan connector can be used as an axle endcap, producing less of a protrusion than the dark-grey connector.

We found no functional difference between the like-sized red, tan and notched yellow rods, other than the built-in connector lock feature of the yellow one (which perhaps avoids the use of extra dark-grey connectors). As stated in the K'NEX instruction books, the grey rod is much more flexible than the similarly-sized black rod. However, the grey rods are usually more numerous in kits than the black ones, so we often had to use grey rods when the more-rigid black ones might have been preferable.

On occasion, a wheel/tire combination can be used horizontally to provide a cushion or shock absorber for moving components. The large red and yellow gears can often be used interchangeably, but the yellow gear's extending teeth provide much more reliable gearbox operation in a design involving perpendicular axles. The small blue gear has an axle-locking capability similar to the larger sizes, but the small grey gear does not, and so is more suitable for decorative uses.

As mentioned in some of the K'NEX instruction books, the two-piece red/yellow ball is essentially fused together once it has been assembled. We found that a ball could be disassembled by a sharp impact, but if you want to create designs using the open hemispherical ball halves, it would be a good idea to keep a disassembled ball in reserve.

K'NEX Industries maintains very high quality control on the production of K'NEX plastic pieces - one reason the various parts fit together so well. Production run numbers are sometimes marked in unobtrusive areas of the individual pieces.

Some of the later K'NEX kits, such as the Launcher series, include a few new parts that make some mechanical designs easier. These parts include a light-blue axle spacer, matched blue/green pairs of hinged connectors (think of an orange connector that can bend in the middle), and a large yellow spoked wheel/gear. These new pieces should provide a capability for improved K'NEX designs, particularly in areas where pivots and hinges are needed. However, if you don't have these new pieces, you can still create a fully-functional and very flexible hinge with a single chain piece, an orange chain clip and a straight orange connector.

The new Solar series contains a small electric motor powered by a separate solar cell. Provided with a long cord, the solar cell can be positioned on a stand a good distance away from the mechanical design containing the motor. We found the solar-powered motor to perform best on designs having lighter moving parts or low torque requirements. More heavy-duty creations would probably function better with the AC electric motor.

The new kits, Cosmic Invaders and Blazing Bikes, provide people-shaped figures that can be rigidly positioned using ball-and-socket joints in new K'NEX pieces.

Here are all the possible lengths using 20-mm orange connector(s) with three or fewer rods:

Copyright © 1999 Balmoral Software. Portions copyright © 1999 K'NEX Industries, Inc. All rights reserved. Republication or redistribution is expressly prohibited without prior written consent.