my new naomi impact is definitely firmer and thinner…unless saddles become softer and thicker over use. 
My first was from udc.uk, bought for the sale-price.
New one is from reagent 20" uni.
That’s weird, I wonder when they switched.
Does this mean the new one is lighter?
ah, weight.
of course, I’ll get the mass of each when I get home tonight. If they are the same, maybe my hot sweaty bottom loosened up the foam making it softer and more voluminous 
Assume any difference in volume of foam on between the two saddles is evenly distrubted along the upper surface of the saddles.
Mass of Naomi Impact saddle from udcUK: 735g(without the 4 seatpost nuts)
Mass of Naomi Impact saddle from newly received reagent uni: 711g(724g with the 4 seatpost nuts)
Difference in mass of the two saddles: 24g
The density of most dense foam stated on the webpage http://www.thefoamfactory.com/blog/index.php/the-differences-and-relationship-between-foams-density-weight-and-firmness is between 10lb/ft^3 to 15lb/ft^3 while foam most commonly found have a density of 1lb/ft^3 to 3lb/ft^3.
Assume the saddle foam density of both saddles are 15lb/ft^3 * (454g/lb) * (1ft/12in)^3 * (1.00in/2.54cm)^3 = .24g/cm^3
Difference in Volume of Foam: 24g / .3g/cm^3 = 70cm^3
Approximate saddle shape to be a rectangular prism.
Assume saddle width to be 10cm, and length to be 30cm
Surface area of the saddle: 30cmx10cm = 300cm^2
Difference in thickness of saddles: 70cm^3 / 300cm^2 = .4cm
The difference in weight of the base, metal reinforcement plate, bumpers, front handle, saddle cover, and front/back bolts/nuts could easily be the source of the difference in mass of the two saddles. However, based on the same parts and reasoning, the difference in mass of the foam might be greater than calculated. Given enough time, the saddles should be taken apart; each part of the saddle should be individually weighed, and the mass of the foam should be used to calculate whether there are different amounts of foam.
Using a vernier caliper and measuring the thickness of the saddle near the seatpost:
Thickness of Naomi Impact saddle from udcUK: 4.96cm
Thickness of Naomi Impact saddle from newly received reagent uni: 4.80cm
Difference in thickness of saddles: .16cm
The main error with this data results from not having any method to ensure the caliper was perpendicular to the saddle or positioned the same way on both saddles.
hmmm…24g might be convincing enough for me to get a new one. I installed mine incorrectly…I guess. I got a KH forged seat post and the bolts that came with the saddle didn’t quite fit right with the four holes in the seat post. Long story short, as I was tightening the little cap things over the bolts, I realized the bolts were coming right through the little caps. Sorry…don’t know the technical term for the little cap. Now my seat is squeaking and moves up and down a little bit. Maybe I should just a get a new seat. My unicycle feels like it needs to be 24g lighter anyway.
oh dang…I just looked up why this happened. Apparently I was given the wrong size bolts, because mine were definitely too short to fit through both the seat post holes AND the saddle cover. Well now it all makes sense! Did you get the correct size bolts?
hm, do you mean you couldn’t tighten them all the way? (still loose?)
Mine seem fine; the saddle is snug on the seatpost.
The udcUK saddle was advertised as having bolts that were too short. However, I was still able to put on a seatpost. My other udcUK naomi impact saddle is on my 29er with kh adjustable seatpost which I believe has a slightly thicker saddle-bolt-on-area, so I had to buy some longer bolts to make it work.
If your bolts are too long…hm, you could buy shorter bolts, file the bolts, break of the rounded part of the nut, or tighten them really hard hoping the rounded part will fall off(happened to one of my nuts on a normal occasion)
edit:
I see what you mean…you only went through the seatpost and not both the cover and seatpost since the bolts were too short. Doing this, you ended up having the bolts too long, and your saddle is slightly loose even when you’ve tightened the nuts all the way.
You could still use the advice above for the too-loose-saddle problem, or you could try to go through the saddle cover. This did take me a bit of persuading of the parts, but the saddle cover takes up a lot less thickness once you actually have it tightened all the way down.
LOL, 24 grams XD
Might be better to ride without a cover, and some missing bolts and bumpers. 
Acorn nut.
Thanks! So the bolt went straight through the rounded part of the acorn nut. But if that isn’t a problem then I will just tighten it more. I’ve given up in trying to fit the bolts through the cover. I just added hot pink zip ties to keep the cover in place.
Anyway. Sorry to divert the conversation. Back to the topic. 24g lighter, but have you noticed anything different while riding on it? Is the shape pretty much the same?
It’s not an issue, it’s just cosmetic. There’s a slight possibility that it could rust where the cap came off but it’s to late to worry about that now. And they are only a few cents each so it doesn’t matter really.
I haven’t ridden it yet, but without putting them side by side, I can’t even tell the difference.
Well, I cant discern any differences. I just went out to ride a teensy bit. The new saddle is on my new trials uni, while I’ve used the other saddle on my 24 and 29 inch unis, so no comparison. But as I said, I doubt there’s any discernible difference
After a few minutes of riding, the saddle felt loose so i tigthened the nuts.
One of the rounded parts of one nut fell off.