Kansas Disc Golf Association

when a disc is made to weigh an approximate weight of 167 what is the difference in how it is manufactured as compared to a 172? more or less plastic or is there a weighting method?

Many times, they have to use a filler to make the weights go up.

I've only been paying attention to this sport for about a year now and haven't really read much about the manufacturing process, but I have a theory / question.

Have any of you wondered why the weight of the discs are hand written onto the back of the discs, probably by some factory worker? To me that means they don't know exactly how much the discs are going to weigh when they come out of the "disc making machines". So they have to weigh them, then mark them after they are manufactured.

It's just a theory of mine... not any fact behind it.

Can anyone tell us if the manufacturer knows exactly what the disc is going to weigh before it comes out? Or will they just know it's going to be within a 10 +/- gram range?

Well I bet they can get closer than +/-10grams because if the heaviest that the discs is supposed to be is 175 max weight, then you don't want to make a bunch of discs that you can't sell. I would think when making discs for 150 class they would want to be very precise with the outcomes too. The markings on the discs are very often wrong, Many people have many discs that weigh over 175 grams (or the highest allowed weight for that specific model), the the most over weight you usually see are around 178g.

I have a 2004 Champion Glow Roc that is 190g, when the Roc mold is only approved to 180. I didn't even weight the disc until after I retired it from the bag. Also, my champion whippet weighed 178g. I think Innova is the worst at marking weights wrong...

Some discs are PDGA approved to 200g, larger diameter stuff like Jaguar and Condor, Te Moko, some other lids....

Also, if you can cruise the PDGA forum, you can check out the "Ask Dave D about Innova" thread. He was the co-founder of Innova, invented the Bevel-edge disc, and still makes the discs at the Innova West location. He answers many questions daily about Innova discs.

Disc mfg.s (to the best of my knowledge) do not have it down to an exact science. This is the reason that overweight discs are sometimes seen. Most commonly, the heavier weights are considered more desirable. The mfg can try and get a batch at the upper limit, but as temperature, color...etc changes, the weight/volume changes. This causes the mfg to end up with a disc which must be re-ground, or one that does not meet standards.
I am somewhat familiar with Discraft's plastic. Modifiers are used to make plastic weight fill different volumes. There are two common modifiers that are easily recognized. The first is the "milky"that you might see in a Z Flick, a disc that was originally created for a smaller weight disc, it needs more weight/volume. The second is the" pearly" which makes the plastic less dense. The pearly was used to good effect in the first run Buzzes. Recently some of the plastics have been changed, allowing discs previously thought too difficult to mfg.to be made. A good example of this would be the Z Drone being used as a Worlds fund raiser.