What is the best RPM for sanding a bowl?

[Kent Reisdorph]

You can get different types of 3" and 2" cutters on Amazon FWIW.

 

[robo hippy]

Well, I never buy anything from Amazon. These cutters are made specifically for hardened die material, so the blades don't go dull instantly. Huge difference between cookie cutters and clicker dies.

robo hippy

 

[Bill Blasic]

I just can't say that I don't buy from Amazon. I rarely go to a store anymore. Amazon, Walmart, Lowes or Home Depot, they all deliver. A 50 mile round trip uses 2 gallons of gas and that's over $8 now and most shipping charges from Lowes and HD are less than that. And then there is Temu and AliEx where I find the strange crap you won't find here. Now before you go off on me I try to buy here first unless the company is trying to rip me off for example: I bought a Samsung Galaxy 7 Watch and when I got it the band was too small so I went to order a band from the Samsung folks and they wanted $50 for a band, come on! Went to Temu and got 6 Galaxy bands for $8 delivered. Now even on AmaZ I can get 3 bands for $8. Even the wife will send in an order to Sam's Club and get a time where she gets there and they bring out the order and load it in the vehicle. We did go into Sam's yesterday to get our Covid shots and this is why she doesn't take me into stores. Even though we absolutely need no groceries we walked out pushing a cart with over $200 worth of groceries. Well we are well stocked in case of a recession

 

[robo hippy]

It was nice when the Woodcraft store was open locally. Supposedly in one of the smallest population areas in all the country. They did supply a lot of specialty items that the big box stores just won't carry. I do order stuff on line now days. I just prefer to buy local. The local Ace Hardware has a hot dog stand that has EXCELLENT dogs, and the booth next to them has fresh cookies. It don't get much better than that.

robo hippy

 

[Terry Vaughan]

I've been disappointed by Cubitron. I cut 2" discs from the larger ones. I find their plastic backing film breaks down quite quickly when I use them inside small bowls. Possibly because they have to flex a lot to fit the curve.

were you using the "mesh" type , or the "hookit" type? I use the mesh type on my ROS, but it does not have good survivability when sanding round things .. the "hookit" version is more fabric backed and holds up much better for sanding on the lathe..

Brian, they are Hookit film discs. I didn't know there were different types.

 

[robo hippy]

I did try some of the mesh type abrasives. For coarser grits like 80 and up, the solid abrasives cut better. Once you get to 220 though, they cut about the same.

robo hippy

 

[Gord Cameron]

I am a big fan of 3M's Cubitron abrasives, but since their introduction 3M has changed the branding and marketing terminology (hookit, xtract etc.) over time and in different countries, and vendors are often confused or sloppy in cataloguing, so it can be more reliable to go by the product numbers:

710W: These are the mesh discs with the herringbone pattern. They are brilliant on a ROS, but the mesh backing optimizes them for dust extraction through a vacuum-equipped sander, at the cost of fraying edges, so probably not the best option for e.g. the insides of bowls, where the edges are vulnerable.
775L: These discs have a film (that is, not mesh) backing; they are available as a solid (no holes) disc or with (small) holes for dust extraction.
732U and 737U: These are the same as the 775L except that they have a paper backing. You might expect them to deteriorate more quickly, but I haven't noticed a difference. They are a bit cheaper and a tad less flexible.

I use the 775L or 732U discs to make 2" and 3" discs for woodturning.

BTW, in reference to a question above, Glenn Lucas sells both a 2" and a 3" punch. I put shorter shafts on mine (an easy bolt swap) so I could use them on my inexpensive 1 ton arbor press. While I use a lot of pre-cut "normal" (aluminium oxide) discs for everyday sanding on the lathe, the dies allow me to make discs from specialty sandpapers like Cubitron.

As Reed noted above, be careful to get a good die; the cheap ones probably won't hold an edge long, especially in this application, where the die has to cut through abrasives.

 

[Alan Weinberg]

I am a big fan of 3M's Cubitron abrasives, but since their introduction 3M has changed the branding and marketing terminology (hookit, xtract etc.) over time and in different countries, and vendors are often confused or sloppy in cataloguing, so it can be more reliable to go by the product numbers:

710W: These are the mesh discs with the herringbone pattern. They are brilliant on a ROS, but the mesh backing optimizes them for dust extraction through a vacuum-equipped sander, at the cost of fraying edges, so probably not the best option for e.g. the insides of bowls, where the edges are vulnerable.
775L: These discs have a film (that is, not mesh) backing; they are available as a solid (no holes) disc or with (small) holes for dust extraction.
732U and 737U: These are the same as the 775L except that they have a paper backing. You might expect them to deteriorate more quickly, but I haven't noticed a difference. They are a bit cheaper and a tad less flexible.

I use the 775L or 732U discs to make 2" and 3" discs for woodturning.

BTW, in reference to a question above, Glenn Lucas sells both a 2" and a 3" punch. I put shorter shafts on mine (an easy bolt swap) so I could use them on my inexpensive 1 ton arbor press. While I use a lot of pre-cut "normal" (aluminium oxide) discs for everyday sanding on the lathe, the dies allow me to make discs from specialty sandpapers like Cubitron.

As Reed noted above, be careful to get a good die; the cheap ones probably won't hold an edge long, especially in this application, where the die has to cut through abrasives.

Very helpful! How do you mount the discs you’ve made—there’s no Velcro backing. And have you found the best place to purchase?

 

[Alan Weinberg]

Glenn Lucas sells both a 2" and a 3" punch

I just purchased and then got an email telling me there’s a 50% tariff on steel so they kindly refunded my purchase and it’s not sold US. BUMMER.

 

[John K Jordan]

Glenn Lucas sells both a 2" and a 3" punch.

I just purchased and then got an email telling me there’s a 50% tariff on steel so they kindly refunded my purchase and it’s not sold US. BUMMER.

Sounds like a good enough reason to go visit Glenn. Twice I almost did, since we've not yet visited Ireland, but haven't gone yet.

JKJ