Wet sanding with rotary

crownline08

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Hi Mike
I have been following your gelcoat polishing videos and I have a question about using a rotary for wet sanding. I have a Griot G8 and it doesn't have enough torque to keep rotating 3" Mirka pad for the smaller areas on the top cap. Also have the Griot GR3 rotary, any issues with using it in the tighter areas instead of hand sanding?
Using the Marine 31 One step compound and polish which is great, I would assume their ceramic coating is equally good. How many coats would you apply? Is there any topper for maintenance? Once the coating wears off what is the process for removing and reapplying? On a fresh water lake in Canada so most boats are only in the water for 5 to 6 months, what do you think the life expectance of the coating would be with proper maintenance. What is proper maintenance other then washing and wiping down regularly? It also looks like Marine 31 has a new version of ceramic coating, what is the difference and when is it available? I saw a picture of it in your latest boat detailing class.
 
First, what surface are you working on, paint or gelcoat? Second, I'd stay away from a rotary unless you have lots of experience due to the ability to cut fast.
 
Using a rotary for any "finish" sanding is asking for trouble. Way too easy to do some serious gouging. It can be done for isolated areas but you better be careful. I'd be doing any areas where the random orbital isn't cutting it by hand.
 
Using it on gel coat to remove oxidization. Waiting on an inter face pad to try on the DA, maybe that will help with rotation
 
When sanding with a DA... you kind of wanting it to oscillate more than spinning at low speed since this would mimic your hand movement. To be honest... I hardly ever have to wet sand a large area. I do most wet sanding by hand. As far as Dry sanding with a DA, I only done it a few times and trust me when I say this..... I was a nervous wreck the entire time.

Too easy to screw up with a rotary even at 600 RPM.
 
Hi Mike

I have been following your gelcoat polishing videos and I have a question about using a rotary for wet sanding.

I have a Griot G8 and it doesn't have enough torque to keep rotating 3" Mirka pad for the smaller areas on the top cap.

Also have the Griot GR3 rotary, any issues with using it in the tighter areas instead of hand sanding?


Hmmm.... the Griot's G8 has tons of torque or power to maintain pad rotation with 3" Mirka Abralon sanding discs. I've used a number of times on car paint and headlights.

Are you turning the speed up on the polisher?


As for sanding with a rotary polishers? When using a rotary to sand it's not sanding - it's grinding. You risk gouging the surface. Because gelcoat is thick, you can probably get away with it but I would try perfecting your technique with the free spinning random orbital G8




Using the Marine 31 One step compound and polish which is great, I would assume their ceramic coating is equally good.

I just taught 27 people how great the Marine 31 Captain's Compound is. Not only did they compound and polish the gelcoat using this product they also used it to polish the acrylic windscreens on both boats. ZERO issues. Zero micro-marring on clear plastic. If this product used crap for abrasive technology - it would have shown up on the clear plastic.



How many coats would you apply?


Product info says you can apply up to 3 coats or 3 layers. You're supposed to wait at least one hour before applying additional layers.

If it were my boat? I'd do 3 layers.



Is there any topper for maintenance?


Any quality SiO2 spray-on, rinse/blast off product would work. Also the Wolfgang Uber SiO2 Coating Wash is what I would use to wash the boat. Good product. Wait for BIG sale and buy by the gallon.



Once the coating wears off what is the process for removing and reapplying?

Re-polish using the Captain's Compound, use panel wipe and then re-coat.



On a fresh water lake in Canada so most boats are only in the water for 5 to 6 months, what do you think the life expectancy of the coating would be with proper maintenance. What is proper maintenance other then washing and wiping down regularly?

In your situation - if you wash boat after pulling out of water, you should get over a year easy. Maybe up to 2 or 3 years. Heck maybe longer. We say up to a year in the HARSH South Florida marine environment.


It also looks like Marine 31 has a new version of ceramic coating, what is the difference and when is it available?

I saw a picture of it in your latest boat detailing class.

In the next week or so we will launch it. WAIT for this coating. I never much liked the old coating. Hard to work with. Tried a number of times - gave up.


:)
 
Hmmm.... the Griot's G8 has tons of torque or power to maintain pad rotation with 3" Mirka Abralon sanding discs. I've used a number of times on car paint and headlights.

Are you turning the speed up on the polisher?


As for sanding with a rotary polishers? When using a rotary to sand it's not sanding - it's grinding. You risk gouging the surface. Because gelcoat is thick, you can probably get away with it but I would try perfecting your technique with the free spinning random orbital G8






I just taught 27 people how great the Marine 31 Captain's Compound is. Not only did they compound and polish the gelcoat using this product they also used it to polish the acrylic windscreens on both boats. ZERO issues. Zero micro-marring on clear plastic. If this product used crap for abrasive technology - it would have shown up on the clear plastic.






Product info says you can apply up to 3 coats or 3 layers. You're supposed to wait at least one hour before applying additional layers.

If it were my boat? I'd do 3 layers.






Any quality SiO2 spray-on, rinse/blast off product would work. Also the Wolfgang Uber SiO2 Coating Wash is what I would use to wash the boat. Good product. Wait for BIG sale and buy by the gallon.





Re-polish using the Captain's Compound, use panel wipe and then re-coat.





In your situation - if you wash boat after pulling out of water, you should get over a year easy. Maybe up to 2 or 3 years. Heck maybe longer. We say up to a year in the HARSH South Florida marine environment.




In the next week or so we will launch it. WAIT for this coating. I never much liked the old coating. Hard to work with. Tried a number of times - gave up.


:)
Thanks for the info, I am waiting on an interface pad to try cause at speed 6 it with stall out unless you are on completely flat surface and applying zero pressure to DA.

I would assume to apply the ceramic coating in the sunshine one would just work in smaller sections as you cannot always be working inside.

Can you put the coating on the non skid areas or will it make it too slippery like wax?

Just purchased the Rupes rotary and the Mille definitely makes working on gel coat a lot easier with better results
 
Thanks for the info, I am waiting on an interface pad to try cause at speed 6 it with stall out unless you are on completely flat surface and applying zero pressure to DA.

Yep - that's the nature or characteristic of free spinning random orbital polishers.



I would assume to apply the ceramic coating in the sunshine one would just work in smaller sections as you cannot always be working inside.

Correct. As I say,

Shrink down the size of the work area



Can you put the coating on the non skid areas or will it make it too slippery like wax?

Most coatings make a surface feel rubbery when dry - I'm not sure about when wet. The problem with coating non-skid is you cannot wipe the channels out that make non-skid what it is - non-skid. So you'll be depositing and then leaving coating in all the channels.

I would opt for the Marine 31 Non-Skid Sealant or wash the boat with Wolfgang Uber SiO2 Coating Wash. You'll get the sealing and water beading effect from a coating by simply washing the boat.



Just purchased the Rupes rotary and the Mille definitely makes working on gel coat a lot easier with better results

Yay team! RUPES makes great stuff!



Apologies for the delay in getting back to you, I've been a tick busy with 27 like-minded people.


Pictures: 2021 Boat Detailing Class - SOLD OUT!


:buffing:
 
Yep - that's the nature or characteristic of free spinning random orbital polishers.





Correct. As I say,

Shrink down the size of the work area





Most coatings make a surface feel rubbery when dry - I'm not sure about when wet. The problem with coating non-skid is you cannot wipe the channels out that make non-skid what it is - non-skid. So you'll be depositing and then leaving coating in all the channels.

I would opt for the Marine 31 Non-Skid Sealant or wash the boat with Wolfgang Uber SiO2 Coating Wash. You'll get the sealing and water beading effect from a coating by simply washing the boat.





Yay team! RUPES makes great stuff!



Apologies for the delay in getting back to you, I've been a tick busy with 27 like-minded people.


Pictures: 2021 Boat Detailing Class - SOLD OUT!


:buffing:
No problem, I know it was your anniversary. I have been speaking with Andre at Marine 31 as well.
FYI I used the new Rupes blue course pad and personally I am happy with the results. I do have the Buff and Shine Uro-Tec like you mentioned coming just to compare. Thanks again for the info I have my first quote today for a customer.
 
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