Author Topic: Help with Rotex RO125 problems  (Read 2237 times)

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Offline samsmith93

  • Posts: 21
Help with Rotex RO125 problems
« on: November 24, 2021, 10:39 AM »
Hi,

I recently purchased a used RO125 having seen them used extensively for resin projects.

I am building up to making a large table, however in the meantime I have been making some resin serving boards (30x50cm approx) to practice on.

The boards are made, they have been through the planer thicknesser, but now it comes to the sanding, and I am having some issues with my rotex.

Clearly the sanding action of the rotex is very powerful, but the issue i am having is that my pads seem to 'gum up' really quickly. I also am getting noticeable swirl marks, of a much larger grit than the pad i am using (so I am presuming this is from the stuff that is adhering to the pad). I have been starting at about 120 grit and working up to 3000 (120, 200, 320, 400, 600, 800, 1000, 1500, 2000, 3000).

I have watched quite a few videos and 'how to' guides, including the helpful festool live sessions and the Larry Smith stuff. I dont have a festool vaccum its attached to a shop vac (via a cyclone), and I have read a lot about how I need to reduce the suction and so I have this turned all the way down.

I am using it in rotex mode (as that is what the festool people suggested as it has more of a polishing action) and I find that seems to be better than the RO mode.

I am hoping for some guidance and help!!!

The boards I have tried so far are West Red Cedar, but I have some oak boards too - however I have not tried it on them yet as it takes me about 20 minutes to clean all the pads up with a brush after ive used them.

The finish on the wood is acceptable, but the finish on the resin is poor. They were poured over 20 days ago so are fully hardened.


Thanks in advance for any help that anyone is able to give me.
« Last Edit: November 24, 2021, 11:10 AM by samsmith93 »

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Offline squall_line

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Re: Help with Rotex RO125 problems
« Reply #1 on: November 24, 2021, 11:32 AM »
Which paper are you using?

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #2 on: November 24, 2021, 12:31 PM »
I am using some of the Deerfos for Festool paper. I have ordered some Platin 2 pads for the higher grits which I plan to use for polishing but they have not arrived yet.

Offline ScotF

  • Posts: 2955
Re: Help with Rotex RO125 problems
« Reply #3 on: November 24, 2021, 01:13 PM »
It looks like you are melting some of the finish. Have you tried slowing down the speed?
« Last Edit: November 24, 2021, 11:40 PM by ScotF »

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #4 on: November 24, 2021, 01:37 PM »
It looks like you are melting some of the fish. Have you tried slowing down the speed?

Fish?

In the stuff i had read it talked a lot about using the rotex on full speed and changing the 'aggressiveness' by changing the paper grit. I will try out slowing the machine down tomorrow and see if that makes a difference.

Thanks

Online Peter_C

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Re: Help with Rotex RO125 problems
« Reply #5 on: November 24, 2021, 01:39 PM »
Could try to keep the sander moving more to disapate heat, along with turning dust collection down to lessen the pull towards the surface being sanded.

As to swirl marks, are you cleaning the surface every time you change sanding grits? Once you get swirl marks move back down to a lower grit and remove them. Watch how much pressure you apply.

I switch between Rotex mode, and just orbital as needed, and never leave it in just Rotex mode. Often I only switch to Rotex mode with a final polishing. Of note I have a RO150 which has a larger orbital pattern. Speed is usually turned down some depending.

Online afish

  • Posts: 741
Re: Help with Rotex RO125 problems
« Reply #6 on: November 24, 2021, 01:41 PM »
I have used many different brands of sandpaper from cheap to expensive.  Hands down the best sandpaper is the 3m cubitron film backed discs.  Its also the most clog resistant I have found.  Try it, it might change your life. 

Do you have any pics of the resin before you start sanding?  What resin are you using? 

Seriously though first step is switching to 3m cube to see if that fixes it.  As far as shop vac vs. dust extractor.  Vacuum is vacuum as long as it isnt getting sucked to tight to the surface this isnt the issue.  You can make a gate valve from PVC to adjust the vacuum if needed.  I use a shop vac. that is plumbed in with 2" pvc and located in a shed for noise reasons.  It works just as good as my ct36ac.   

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #7 on: November 24, 2021, 02:23 PM »
I have used many different brands of sandpaper from cheap to expensive.  Hands down the best sandpaper is the 3m cubitron film backed discs.  Its also the most clog resistant I have found.  Try it, it might change your life. 

Do you have any pics of the resin before you start sanding?  What resin are you using? 

Seriously though first step is switching to 3m cube to see if that fixes it.  As far as shop vac vs. dust extractor.  Vacuum is vacuum as long as it isnt getting sucked to tight to the surface this isnt the issue.  You can make a gate valve from PVC to adjust the vacuum if needed.  I use a shop vac. that is plumbed in with 2" pvc and located in a shed for noise reasons.  It works just as good as my ct36ac.


So I just went out and tried doing a face on lower speed at a 1 on the rotex, this seems to have significantly improved the situation on the lower grits. Much less material sitting on the pad after I have sanded.

The problem starts to reappear at the higher grits >1000. I wonder if I simply need to wait for the platin 2 pads and if that will solve the higher grit issues.

If that doesn't work then I will have a look into the 3m cube discs you suggest - although as I can see they only go to 400.

I use a shop vac and have made a valve to allow me to adjust the suction level so I can go from basically nothing to full.

I am using Glasscast 50, it was poured about a month ago so is fully hardened for all intents and purposes.


Online afish

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Re: Help with Rotex RO125 problems
« Reply #8 on: November 24, 2021, 02:31 PM »
Ok, Im not familiar with glasscast but resins do vary in hardness so if its a softer resin it would probably tend to gum up more and yes the cubitron is 400 and under.  Over 400 I use water with a drop of soap in a mist bottle to keep the disc cool and clean. 

Offline Crazyraceguy

  • Posts: 831
Re: Help with Rotex RO125 problems
« Reply #9 on: November 24, 2021, 07:52 PM »
Gumming up comes from a few factors or a combination of them.
The hardness of the material
The grit of the abrasive (courseness)
Swarf removal
Heat, though usually only with plastics

The hardness of the material is a big one. Soft things tear rather than cut. This plays with all of the othe r factors. The more course the paper cuts better, rather than rubbing and making heat, but it needs the swarf removed or that gets reground back into the mess.
Speed also has a effect, especially on heat.

My advice, slow down the sander, start with a lower grit, turn the suction down, but still keep the surface clean. Most of my sanding, that will lead to polishing, is with Solid Surface material and acrylics. The acrylic is far more difficult to do because it is far softer in the first place.

Just realize that "cured" doesn't necessarily mean "hard", certain plastics only get so hard. Maybe looking into different brands or formulas of resins might yield better results? Harder materials "take" polishing better, as in higher shine, and they hold that shine longer too. Softer plastics "wear in" to what ever level of polish that their everyday use demands.

CSX
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PS420 + Base kit
OF1010
OF1400
MFK700 (2)
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Online Cheese

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Re: Help with Rotex RO125 problems
« Reply #10 on: November 24, 2021, 10:59 PM »
First off I'd start by also slowing down the Rotex.

I've done a couple of slabs with epoxy using a RO 125 and an ETS EC 125. I treat the wood and the plastic as 2 different materials especially in the initial sanding/flattening task when you're using large grits.

The speeds you use on wood will cook the epoxy while the speeds you use on epoxy will take forever to sand the wood.

I start with the RO 125 by working to flatten/blend the epoxy to the same height of the wood, just get it close but work the epoxy first because it's the hardest surface and will need the most machining. Set your speeds & feeds to make the epoxy happy. 

Clean the surfaces, put a clean sanding disc on and then work the wood to blend in to the epoxy...set speeds & feeds to make the wood happy.

Continue this approach and at sometime both the epoxy and the wood will feel evenly leveled and this is the time I bring in the ETS EC 125 to produce a uniform surface across the entire surface. My guess is that this is now in the 320/400 grit range.

Continue on with the sanding but don't dwell too long on the wood areas as they will still erode faster than the plastic areas. Also a mist of water on the plastic areas will produce a nicer finish.

When going to the next higher grit, wipe all of the surfaces especially if you misted the epoxy areas as this swarf will only get reground into the epoxy.

Clean...clean...clean between sanding applications. I usually vacuum first and then wipe with a microfiber towel. If you use the same microfiber towel to wipe successive grit levels, fold it over to make sure the previous grit will not be redeposited on the new wiped surface.

Only for the final polishing do I go back to the Rotex in the geared mode. This is when compounds and polishing materials are used.

Here's an example of the products I used for a walnut countertop...some 6", some 5" and some 4" squares. The form doesn't matter, only the grit does.

And to those naysayers that say they don't need the capabilities of both a 5" & 6" sander, notice the first two discs are 6" while the remaining ones are 5" or less. This was accomplished with an ETS EC 125 fitted with both a 5" and a 6" pad. I'd normally need 2 sanders to accomplish this task.

Final result, American walnut with West System epoxy.




« Last Edit: November 24, 2021, 11:13 PM by Cheese »

Offline Crazyraceguy

  • Posts: 831
Re: Help with Rotex RO125 problems
« Reply #11 on: November 25, 2021, 08:30 AM »
cheese, what is that router base in that photo? It looks like it could be used for edge guides and or a trammel of some kind, but also Porter Cable bushings too?
CSX
DF500 + assortment set
PS420 + Base kit
OF1010
OF1400
MFK700 (2)
TS55, FS1080, FS1400 holey, FS1900, FS3000
CT26E + Workshop cleaning set
RO90
RO125
ETS EC 125
RAS115
ETS 125 (2)
TS75
Shaper Origin/Workstation

Online Cheese

  • Posts: 9108
Re: Help with Rotex RO125 problems
« Reply #12 on: November 25, 2021, 10:13 AM »
cheese, what is that router base in that photo? It looks like it could be used for edge guides and or a trammel of some kind, but also Porter Cable bushings too?

It is an edge guide... [smile]... from Micro Fence, I've since drilled it to be used with both the 1010 & 1400 routers. Currently Micro Fence has a 10% off sale plus free shipping.

https://microfence.com/product/universal-router-plate-kit/

1010 mounting holes are red, 1400 mounting holes are yellow.




Here it is being used on a rail to make shower niches from Kerdi board.


Offline Crazyraceguy

  • Posts: 831
Re: Help with Rotex RO125 problems
« Reply #13 on: November 25, 2021, 05:18 PM »
Oh, ok. Is there some advantage to that, over the original Festool edge guide?
It is nice to sit flat (off the rail), but it does take more width too.
CSX
DF500 + assortment set
PS420 + Base kit
OF1010
OF1400
MFK700 (2)
TS55, FS1080, FS1400 holey, FS1900, FS3000
CT26E + Workshop cleaning set
RO90
RO125
ETS EC 125
RAS115
ETS 125 (2)
TS75
Shaper Origin/Workstation

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #14 on: November 26, 2021, 01:21 PM »
So I spent this afternoon messing about trying various degrees of suction and various speed settings on the sander.

On Rotex mode the pad just cloggs up, irrespective of the amount of suction that is there.

I tried sanding just my softwood worktop however and it sands that absolutely fine without clogging the pad!!

On my epoxy/wood project however it clogged up really badly.

I tried it on random orbit mode - much less of an issue with the clogging up, however get really bad pigtails and swirls - small bits still seem to be clogging on the pad.

I’m wondering if maybe it is the pads I’m using - I’ll do a post asking if anyone has used the Deerfos ones.

It’s rather frustrating as I went from a cheapo crappy RO sander to this thinking it would be the panacea of sanders! But no joy as yet……

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #15 on: November 26, 2021, 01:44 PM »
To add to the previous post the other thing I found confusing is that the boards I am sanding are made of oak, and part of it is cured epoxy resin,

I wondered if it was the resin that was causing the buildup on the sanding pads however
Even when I try and just sand the oak areas avoiding the epoxy I have the same issue.

Offline squall_line

  • Posts: 1032
Re: Help with Rotex RO125 problems
« Reply #16 on: November 26, 2021, 01:45 PM »
It’s rather frustrating as I went from a cheapo crappy RO sander to this thinking it would be the panacea of sanders! But no joy as yet……

When it comes to sanding, it's not just the sander, but the abrasive as well.  That doesn't mean "you must use Festool for the sander and the abrasive", but if you were having poor results with a previous sander and all you changed was the hardware, it may be time to look at a different abrasive as well.  Some are more prone to clog than others, and there are plenty of different brands/types that are designed to work better on different surfaces (for example: Festool Rubin is designed for raw wood but not finished wood, Granat is better at working with finished/painted wood).

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #17 on: November 26, 2021, 04:07 PM »
In principle I don’t mind buying some granat pads if the consensus is that it’s the pads at fault

Online afish

  • Posts: 741
Re: Help with Rotex RO125 problems
« Reply #18 on: November 26, 2021, 06:01 PM »
 [doh] There is no magic wand.  Cheap paper sucks.  To spend 600 on a sander then slap some bargain bin paper on there is one step forward 3 steps back.  spend the 8 bucks and try the 3m here If you like it you can get more grits.  If not your out 8 bucks.  Sorry, last time I will  [dead horse]
and NO rotex mode till you move to polishing stage. 
« Last Edit: November 26, 2021, 07:07 PM by afish »

Offline Crazyraceguy

  • Posts: 831
Re: Help with Rotex RO125 problems
« Reply #19 on: November 26, 2021, 07:26 PM »
What grit are we talking here? Also, what is the goal at this point? Are you leveling, smoothing, polishing?
CSX
DF500 + assortment set
PS420 + Base kit
OF1010
OF1400
MFK700 (2)
TS55, FS1080, FS1400 holey, FS1900, FS3000
CT26E + Workshop cleaning set
RO90
RO125
ETS EC 125
RAS115
ETS 125 (2)
TS75
Shaper Origin/Workstation

Online afish

  • Posts: 741
Re: Help with Rotex RO125 problems
« Reply #20 on: November 26, 2021, 08:33 PM »
I too was curious if his troubles are isolated to a certain grit range.  1st step is good paper though regardless.  Granat is my 2nd pic. Not sure how much or the condition of the resin hes starting with and how much he needs to remove.  I grain fill with epoxy but apply very thin coats with a squeegee, so there isnt a ton of sanding.  However doing a pour is different and I would assume he has more to flatten.  However by the time he reaches 220 to 400 and above there shouldnt be enough sanding to cause excessive heat.  I would follow these basic rules for success:

1. Start with good quality sandpaper no matter what grit you are using
2. NO rotex mode for "sanding finishes" rotex only once you reach the polish stage and are using a foam or lambs skin type pad after you have sanded through 1500 or higher
3. slow the sander speed like 2 or 3
4. no pressure especially in the higher grits just guide the sander
5. adjust suction as low as possible to still get good dust but not pull sander down (that's the same as pressing down on sander)
6. work up through the grits with no large jumps between grits
7. 400 and higher you can use a light mist of water with a tiny bit of soap I use about 1/2-1 drop of dawn per 32oz. of water it will work wonders (make sure your sanding sheet is wet approved) film back.  You are not flooding the surface like wet sanding a car. Frequent light mist when your slurry starts becoming more like sludge.  wipe with micro fiber and re mist as needed
8. clean between grits ( I blow with air first to remove 98% off part and bench then wipe with damp not wet micro fiber
9.  If you need to remove a lot of material at the start use some type of cutter like a router with a fly type cutter and sled, card scraper etc.   
10. Soft pad seems to help too.  Once I reach the higher grits I use a super soft foam interface pad on a pneumatic sander for "wet type" sanding. 
11. Remember High Gloss finishes are tough and it takes time thats why its expensive. 
12. Always Keep sander moving
« Last Edit: November 26, 2021, 08:39 PM by afish »

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #21 on: November 27, 2021, 04:33 AM »
What grit are we talking here? Also, what is the goal at this point? Are you leveling, smoothing, polishing?

So I’ve got boards which have been through the planer thicknesser. I’m trying to smooth them over and then particularly when it comes to the epoxy areas get them polished to a good shine so they are glossy.

I’ve been starting at 120 grit then working up to 3000
120,240,320,400,600,800,1000,1500,2000,3000

I had read that platin 2 was a better option for the higher grits (1000,2000,4000) but that hasn’t arrived yet.
Mainly the swirling issues appear at the higher grits >600. The photo I’ve attached is of a 1000 grit pad I believe after about 20 seconds of use.

I’d brushed and wiped the workpiece and brushed the pad to make sure it was completely clean before use, the small specs that have built up are what I believe to be responsible for the swirls!!!
« Last Edit: November 27, 2021, 04:44 AM by samsmith93 »

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #22 on: November 27, 2021, 04:36 AM »
[doh] There is no magic wand.  Cheap paper sucks.  To spend 600 on a sander then slap some bargain bin paper on there is one step forward 3 steps back.  spend the 8 bucks and try the 3m here If you like it you can get more grits.  If not your out 8 bucks.  Sorry, last time I will  [dead horse]
and NO rotex mode till you move to polishing stage.

I can’t seem to find them 3M pads in a multipack as readily available in the UK. I can get hold of a sample pack of granat for about £25 which I’m happy to try!

I really welcome as much criticism as people are prepared to give me! Clearly I’m doing something wrong so I’m happy to learn!

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #23 on: November 27, 2021, 05:11 AM »
I too was curious if his troubles are isolated to a certain grit range.  1st step is good paper though regardless.  Granat is my 2nd pic. Not sure how much or the condition of the resin hes starting with and how much he needs to remove.  I grain fill with epoxy but apply very thin coats with a squeegee, so there isnt a ton of sanding.  However doing a pour is different and I would assume he has more to flatten.  However by the time he reaches 220 to 400 and above there shouldnt be enough sanding to cause excessive heat.  I would follow these basic rules for success:

1. Start with good quality sandpaper no matter what grit you are using
2. NO rotex mode for "sanding finishes" rotex only once you reach the polish stage and are using a foam or lambs skin type pad after you have sanded through 1500 or higher
3. slow the sander speed like 2 or 3
4. no pressure especially in the higher grits just guide the sander
5. adjust suction as low as possible to still get good dust but not pull sander down (that's the same as pressing down on sander)
6. work up through the grits with no large jumps between grits
7. 400 and higher you can use a light mist of water with a tiny bit of soap I use about 1/2-1 drop of dawn per 32oz. of water it will work wonders (make sure your sanding sheet is wet approved) film back.  You are not flooding the surface like wet sanding a car. Frequent light mist when your slurry starts becoming more like sludge.  wipe with micro fiber and re mist as needed
8. clean between grits ( I blow with air first to remove 98% off part and bench then wipe with damp not wet micro fiber
9.  If you need to remove a lot of material at the start use some type of cutter like a router with a fly type cutter and sled, card scraper etc.   
10. Soft pad seems to help too.  Once I reach the higher grits I use a super soft foam interface pad on a pneumatic sander for "wet type" sanding. 
11. Remember High Gloss finishes are tough and it takes time thats why its expensive. 
12. Always Keep sander moving

Thanks for such a comprehensive response,

So my boards have been sanded so many times in various ways now they are very flat! Basically I’m just trying to get the small swirls out of them and leave them with a glossy finish. The oak comes up beautifully but it is much more forgiving of the marks than the resin area. The marks that are left are too big to polish out.

R.e 1 - I’ve been using ‘deerfos’ paper, haven’t found much in the way of reviews, I’m going to try some granat as clearly people have good experiences with that. I also have some Platin 2 coming for the higher grits - I wonder if the softer ‘foam’ type pad will help with swirls at the higher grit ranges.

R.e 2 - I’ve watched so many videos about rotex v RO mode - some people say use rotex the whole time, some people have said use initially then at the end for polishing. I seem to get much worse swirls with the RO mode when I get to 600 grit and above.

R.e 3 - I started off using it at a 4 or 5, then someone suggested this may be causing too much heat, and I read about how I should adjust the aggressiveness of what I’m doing by changing the pad, not the speed, so I’ve been using it on 1 since then.

R.e 5 - I’ve got it attached to a shop extractor, I don’t own a CTS. Its adjustable however from basically zero to very high, and I’ve messed around a lot with the degree of suction, it almost seems to depend on the grit range as to how much suction is needed.

R.e 7 - I did briefly try wetting it as someone suggested that, I didn’t use a mister though, I’ll get one and try it. I did have even worse buildup with that though, it caused a thicker paste like buildup on the pad.

R.e 8 - I’ve been wiping the piece in between each grit, I’ve also been cleaning the pads each time before I use them. The buildup on the pad is so solid, I can’t air blow it off I have to brush it with a stiff toothbrush basically.

R.e 9 - Before I’ve started sanding the boards have been through a planer thicknesser so they are flat, I’m just sanding out the marks from the planer and then smoothing over.



Thanks again for a helpful reply, I’m wondering with your last few suggestions whether I should stop sanding at about 800 grit and change over to polishing with a compound of some sort.


Online afish

  • Posts: 741
Re: Help with Rotex RO125 problems
« Reply #24 on: November 27, 2021, 07:44 AM »
If you cant get the 3m in the UK get the granat.  I havent used platin but Im assuming its similar to 3ms trizact which is another good product designed for clear coat.  once you reach those higher grits it really shouldnt be taking much to sand out.  If your making paste then you are sanding to much between spritzing and wiping 1-2 passes then wipe.  I think you will need to go up to 1500+ before trying to compound.  Anything less than that and its not going to polish well.  I typically use Meguiers 101 and 201 because its easy to get around me and works well and isnt overly expensive.  I dont have the bottle in front of me but Im pretty sure the 101 (heavy cut) says it will remove up to 1200 grit scratches.  In my experience thats even optimistic.  I like to go to around 3000 then break out the polish. 

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #25 on: November 27, 2021, 10:12 AM »
If you cant get the 3m in the UK get the granat.  I havent used platin but Im assuming its similar to 3ms trizact which is another good product designed for clear coat.  once you reach those higher grits it really shouldnt be taking much to sand out.  If your making paste then you are sanding to much between spritzing and wiping 1-2 passes then wipe.  I think you will need to go up to 1500+ before trying to compound.  Anything less than that and its not going to polish well.  I typically use Meguiers 101 and 201 because its easy to get around me and works well and isnt overly expensive.  I dont have the bottle in front of me but Im pretty sure the 101 (heavy cut) says it will remove up to 1200 grit scratches.  In my experience thats even optimistic.  I like to go to around 3000 then break out the polish.

I’ve got some megs 101 and 201 which I’ve used on the car with a DA before so I can give them a go on it, just gotta get to the 1500 grit ish state without these bloody swirls

Online afish

  • Posts: 741
Re: Help with Rotex RO125 problems
« Reply #26 on: November 27, 2021, 01:05 PM »
I dont do the thick epoxy pours or live edge slab work like IM assuming you are doing.  Dont those who do top coat the epoxy too.  Epoxy doesnt like UV so I would think you would be topcoating with some type of urethane for protection and polishing.  I know epoxy polishes but if you are having issues with the resin then maybe just sand it to 400 and lay down some 2k clear. then polish that

Offline samsmith93

  • Posts: 21
Re: Help with Rotex RO125 problems
« Reply #27 on: December 01, 2021, 11:07 AM »
So - I got hold of a sample pack of the Granat pads from ebay (https://www.ebay.co.uk/itm/192886095956) and gave them a go.

For the most part, the dust situation is improved versus the deerfos cheaper pads I was using.

The problem still however seems to be at about the 600-1000 grit range I get some build up on the pads, and I believe this is what is leaving these swirl marks appearing in the work, which are much deeper than their respective grits, and therefore don't sand out with the higher grits - so when I get on to the polishing phase they are still visible. (If I go down a grit to sand them out then I still end up with the same issue as I get to the 600-1000 stage as I go up again).

The Megs 105 and 205 'apparently' can remove 1200 grit scratches - but i'd say the marks i get are in something around the 400-600 grit area so obviously they don't come out.

The results I am getting are certainly a huge improvement from what I had when I started asking for advice on this.   

I welcome any other suggestions and thoughts that might help guide me to the solution!
« Last Edit: December 01, 2021, 11:11 AM by samsmith93 »

Offline Lbob131

  • Posts: 546
Re: Help with Rotex RO125 problems
« Reply #28 on: Yesterday at 03:37 PM »
Below is an overview of common grit numbers and their recommended applications:

P40-P60: For stripping finishes and paints, smoothing rough pieces of lumber, removing stock from thicker pieces of metal, or removing knots or bumps in wood pieces.
P80: This is the recommended starting grit for working with hardwoods. It also does an effective job of removing shallow scratches from metal surfaces.
P120: Recommended starting grit for softwood sanding.

P180: Smoothing surface irregularities and raised wood grains.
P220: Appropriate for wood stain preparation or commencing surface finishing.
P320: Wet sanding or sanding between coats. (Be sure to use an abrasive that’s compatible with wet applications.)
P400: This grit does a good job of preparing a surface for finishing oils or smoothing top coats. It is also used as a finishing grit for many materials.

P600 and up: Any grit above the 600 range is recommended for plastics and metals, fine wet sanding, or preparing a surface for polishing. Abrasives scratch metal far easier than they scratch wood. Scratch marks also aren’t as easy to remove from metal as they are from wood. Therefore, fine to ultra-fine grits from 600 to 1,200 are most useful when polishing metal.





Offline Lbob131

  • Posts: 546
Re: Help with Rotex RO125 problems
« Reply #29 on: Yesterday at 03:41 PM »
The problem still however seems to be at about the 600-1000 grit range

I  didn't  think  600-1000   would  leave  swirl  marks.
Perhaps  the  600-1000   is  just  highlighting  the swirl  marks  from  previous  coarser  grits?

I have  the Rotex 150  and  90.
« Last Edit: Yesterday at 03:43 PM by Lbob131 »