School me on bases: How much worse is extruded actually

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Thelongride
Posts: 45
Joined: Thu Jun 06, 2019 8:53 am
Location: Washington

School me on bases: How much worse is extruded actually

Post by Thelongride »

So I'm aware that sintered is denser and wax penetrates more deeply. But extruded just grinds and finishes up so much nicer (plus it's cheap!).

So those of you with direct experience: How much slower, and how much more prone to nicks is extruded vs the lower density sintereds.


Knowledge on nordic bases is welcome too (what's the deal with white "warm condition" bases).
TimW
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Joined: Sun Apr 26, 2020 11:56 am

Re: School me on bases: How much worse is extruded actually

Post by TimW »

A sintered base is porous and will absorp wax, whereas an exstruded base is not porous and will actually not absorp wax at all, only a bit will stick to the surface. if you don't wax, a extruded base could actually be faster.

For me, on a snowboard a fast base is invaluable( especially if you encounter flats with most friends on skis). I gladly spend a few euros more on a board for that, but I don't build commercially.
A fast sintered base can make a dramatic difference, even with lazy waxing. I bought a 100m roll of some isosport race base a long time ago (also because of difficulty getting base at the time). I am not even halfway the roll, but i am still very happy I spent the money.

In terms of durability I don't think a sintered base is necessarily much better than an extruded base. I don't have much exterience with extruded bases, but my sintered base is not very hard.
Thelongride
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Joined: Thu Jun 06, 2019 8:53 am
Location: Washington

Re: School me on bases: How much worse is extruded actually

Post by Thelongride »

Thanks, I had no idea extruded did not absorb wax.

I guess my assumption was that it did, just to a lesser degree.
gav wa
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Location: Perth

Re: School me on bases: How much worse is extruded actually

Post by gav wa »

The way I understood it from a Ptex manufacturer is that extruded base has about 40% amorphous content and 60% crystalline content.
Sintered is the opposite 60% amorphous. And when warmed the amorphous freckles draw in wax a bit like sugar dissolving in warm water. And as it cools some squeezes back out.
So they both with hold wax but sintered holds more. Sintered is much harder to work with and is longer lasting. I find extruded material much easier to work with and grinds really easily and quickly but obviously isn't as durable.
I've ridden some fairly fast extruded bases and some horribly slow sintered bases. Sintered is better but extruded isn't exactly a rubbish product.
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chrismp
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Re: School me on bases: How much worse is extruded actually

Post by chrismp »

gav is right, extruded base does absorb wax. Isosport lists a wax absorption of 1.4 g/m3 for one of their black extruded bases and a comparable black sintered base is listed with 1.9 g/m3.

Unfortunately, they don't give any comparable numbers on the speed of the bases. They only state that sintered bases are the optimum when it comes to speed and durability. I am sure they have specific data on the speed though.
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