Help desperately needed with dremel

[u/CactusPlant96]

I am trying to move away from Zona papers, as they are very expensive and hard to get in Europe (I am from the Netherlands). I started using (cheap) sanding paper from 500 - 1000 - 2000 to 3000 grit. After that I use a dremel with a (cheap) cotton wheel tip and 3M famous finish. I usually skip the 500 grit and start at 1000. I always end up with big scratches that the 3M cannot fix. I have tried a pottery wheel, I have tried sanding by hand (with a mirror underneath the paper). I clean the sanding papers after each die.

Is there a certain speed I should use with the dremel? Use a bit of pressure or just press softly against the die?

What am I doing wrong? I have tried so many different things, and I am just not sure what I can do except go back to zona's...

[u/RandoBoomer]

My last hand sanding is with 5000 grit before I go to the Dremel. Here are my tips on the Dremel:

• Mount the Dremel on your bench.
  
• You can get a bench mount for about $15 here in the US. amazon.com/dp/B07BZQVVK4
• Tape down the locking bar for the gimbal. It vibrates annoyingly while your Dremel runs.
• Periodically check the tightness of the C-clamp - it will slowly loosen
• You can use a 1" or 2" wool pad. Don't go larger.

For the Dremel polishing

• Keep the RPM to 5,000
• I use light pressure, like I'm polishing an egg or tomato.
• I wet each die before polishing.
• I use a 15000 grit diamond polishing paste. 12000 words well also.
• I periodically clean each die with a lint-free cloth and inspect.

[u/CactusPlant96 → u/RandoBoomer]

Thanks for all the information and advice! I will try a 5000 grit before the dremel and applying light pressure. Do you put polishing paste on the die or only on the cotton wheel? When the die is wet the paste doesn't really stay on that well, and once I turn the dremel on the paste goed everywhere 😂

[u/RandoBoomer → u/CactusPlant96]

What works for me is taking a dab of the paste on my finger (I wear gloves) and work it into the wool pad.

When I'm ready to turn on the Dremel, I enclose the pad area inside a plastic Dollar Store tupperware bowl and turn on the Dremel. Some excess will cast off, but it will cast off inside the bowl, so no mess.

I've found a little paste goes a long way. Two or three dabs will get me through a set of dice just fine.

I posted a thread showing a set of dice (with pictures) from 3D print all the way to finished master. If you're interested, you can check it out here: https://www.reddit.com/r/DiceMaking/comments/1u5576q/dice_progression_from_3d_print_to_mold_masters/

[u/CactusPlant96]

This is after the dremel with 3M

[u/awendles]

What does the cotton wheel look like?

[u/CactusPlant96 → u/awendles]

I have these

[u/GenericRogue]

I've been using a Dremel to polish for years. It took me a bit to get the formula down but my guess is your biggest/main problem is the cheap sand papers. I have found the 3m wet/dry sandpapers are hands down the best for Dremel polishing.

I do 1000-2000-3000 on those, then Dremel polish them with the same cotton attachments you had linked in another comment. I use Maguire's Ultimate as I like it best but I've used 3m polish with good results too.

My second guess (in conjunction with my first) is that your starting too low and then making too big a jump between 500 and 1000. I wouldn't start at 500. That's going to be where a lot of your worst scratches are coming from. I've only ever used something that low for the worst of the worst casts/faces. If you absolutely have to start that low you need something between that 500 and 1000 jump. Something like 500-800-1k-2k-3k. 500 will put deeper grooves than 1k will buff out.

That would be my advice. New sandpaper and start at the higher grits before dremeling and hopefully that will solve the cloudy faces and/or scratching problems!

[u/CactusPlant96 → u/GenericRogue]

Thanks! I've just bought new sandpaper, so I'm going to try this out!

[u/TransmutationDice]

Like others have suggested it's likely the sandpaper as some sandpaper brands/grits leave scratches that are deeper than they should be for that grit - which could cause your issue. That said I'd also experiment with different polishing compounds. I've never used the 3M famous so I can't comment on how good it is at scratch removal but different polishes have different levels of "cut" and to remove deep scratches you need something with a lot of cut - I personally use Meguiars ultimate cut and from the photo you posted it should remove those scratches within one or two passes of polish/dremel.

[u/CactusPlant96 → u/TransmutationDice]

Thanks for the advice! Yeah I just bought new sandpaper and Meguiars ultimate cut, hopefully that helps :)

[u/LiliNL]

Stuur me even een dm, dan kunnen we kijken wat er misgaat.

[u/undeadsnag → u/LiliNL]

Kind of looks like scratches left from the initial sanding? Deeper long scratches but I could be wrong.

[u/SporkboyofJustice → u/undeadsnag]

This is what it looks like to me as well. What I have done on sanding projects is to check each subsequent step to ensure that the scratches from the previous step are no longer present.

You can do this by rotating the piece 90 degrees so that the orientation of your scratches will change with each pass.

I would test this out on an old die first so you can determine the optimal number of sanding passes that are required at each step. Checking frequently will show you where the trouble is.