So when you sand with a low grit, it cuts deeper grooves into the tire. Then when you hit it lightly with a higher grit, it knocks the peaks off and puts lighter grooves on top of and across the deep grooves. You typically want to cross hatch to get the best results.Plateau finish ?
So you have to use a belt sander not disc to achieve this effext ?So when you sand with a low grit, it cuts deeper grooves into the tire. Then when you hit it lightly with a higher grit, it knocks the peaks off and puts lighter grooves on top of and across the deep grooves. You typically want to cross hatch to get the best results.
As stated above, a lot like a cross hatch in a cylinder.
So you have to use a belt sander not disc to achieve this effext ?
I use a 7 inch wheelSo you have to use a belt sander not disc to achieve this effext ?
Same as you would finish an engine cylinder. Progressively finer grits at slightly different angles. It smooths off the high spots, or sharp edges, of the finish leaving more surface area while retaining some of the deeper grooves/scratches. Think "plateau" rather than "peak."Plateau finish ?
I can get a tire sanded to look like that in about 2 minutes. One thing that sticks out to me is the hatching all the way across shoulder-to-shoulder. I keep the course sanding between the dots. Then get some 200 on an orbital sander and carry it out a little further. Then some 320 on an orbital sander and carry it out a little further. Finish is off by hand with some set 600. Gotta keep the tire wet the whole time and run a sponge over it to pickup the rubber crumbs that stick to the tire. It takes time but they come out looking glassy. Someone told me I'm good at it (I don't know about that), consequently I get to cut a lot of tires
Yeah we did. And I noticed afterwards that the surface of the tires was brown, just like the track. I know now if the face of the tire stays black the tire is getting into the track. And now if I see a kart that isn't getting around the track very well its tires aren't very black.So you got much better with the fine grind?
Keep in mind the finer you go (220+) on used tires, the more critical it is to keep the tire cool or it will gum and burn quicker than 120 or 180. You may want to mix methanol with another substance like windex that doesnt evaporate as fast and do them by hand on the machine. As you know, new tires are a little more forgiving.This is a battle of the preferred methods, lol.
for whatever it's worth, I've had really good luck over the years running a belt sander with methanol spray to cool... I start with a 120 grit and finish with a 180. I used to do the whole two direction cross hatch but for whatever reason, I've come to prefer just the single direction hatches.
After reading everyone's posts, I'm tempted to try a 220 grit. I've had a lot of success with this current method though on burris, vegas and maxxis. Been doing customer tires like this for a while also.
I've actually noticed that the Maxxis seem to make more rubber dust than Burris or Vega. I tried the windex thing (ammonia free) and just did not like it. it didnt evaporate that well and allowed the rubber dust to stick to itself and stick to the sanding belt. Perhaps I'll try again 75% methanol, 25% windex.Keep in mind the finer you go (220+) on used tires, the more critical it is to keep the tire cool or it will gum and burn quicker than 120 or 180. You may want to mix methanol with another substance like windex that doesnt evaporate as fast and do them by hand on the machine. As you know, new tires are a little more forgiving.
That's because maxxis being syntheticI've actually noticed that the Maxxis seem to make more rubber dust than Burris or Vega. I tried the windex thing (ammonia free) and just did not like it. it didnt evaporate that well and allowed the rubber dust to stick to itself and stick to the sanding belt. Perhaps I'll try again 75% methanol, 25% windex.
Maybe its the tire lathe or sander speed I prefer but methanol seems to cool it, keep the dust from sticking, open the pores a tiny bit and evaporates fast. I blow through about half a gallon of methanol on a brand new set of tires. lol
It smells really bad when you get to sanding and grinding on the tire, but I put track tack tire wash in a spray bottle and keep spraying it on. Sticks to the tire really well.I've actually noticed that the Maxxis seem to make more rubber dust than Burris or Vega. I tried the windex thing (ammonia free) and just did not like it. it didnt evaporate that well and allowed the rubber dust to stick to itself and stick to the sanding belt. Perhaps I'll try again 75% methanol, 25% windex.
Maybe its the tire lathe or sander speed I prefer but methanol seems to cool it, keep the dust from sticking, open the pores a tiny bit and evaporates fast. I blow through about half a gallon of methanol on a brand new set of tires. lol
Oh yea, there's no "my way is right and everyone else is wrong" attitude from me, anyhow. I learn new things every day. Having a teachable spirit is key to getting better all the time.I think its actually kind of cool that everyone who messes with tires learns things a certain way and does things just ever so different from the next.
I'm tempted to take what I've learned here and try a "smoother polished/ finer grit method" cut on my lower duro "gumball" sets of tires.
What would be neat would be to find a way to test the cut profile differences exclusively. There's too many other variables like chassis, driver, weight, prep, etc-etc.
My tire sensei from a dozen years ago taught me much of what I know now with a belt sander, but he himself used an electric variable speed buffer when cutting some other customers tires who raced in other parts of NY. I tried it once many years ago and I wasn't able to replicate what I saw and what I had been using/ current methods was working really really well. I think its time to practice this on a few sets!
We cannot learn from what we do not attempt.
Very well put.Oh yea, there's no "my way is right and everyone else is wrong" attitude from me, anyhow. I learn new things every day. Having a teachable spirit is key to getting better all the time.
You do what works best for you and your customers, despite what your competition, or even the guy pitted next to you, is doing.