Burnishing - how many RPM?

[LottyAfrica]

Hi all,

I am looking at buying a bench drill press, to mount a wooden burnisher in. 

There's different types with different speeds.

Please could you share with me what the best speed for burnishing is, approximately?

The bench drill I'm looking at, has a slowest speed of 580 RPM. I would like to know if that is OK, or too fast?

Thanks

[TxLeather2]

depends on the diameter of your burnisher

[LottyAfrica]

9 minutes ago, TxLeather2 said:

depends on the diameter of your burnisher

It’s a decent sized one

not at home now so can’t measure it for you..

[TxLeather2]

I would say that 580 RPM is a good speed, no more than that (IMHO)

[heydox]

The bench top Cobra burnishing machine that I use has an RPM range of 2000 to 3500. 580 may be too low to get an effective burnish, but you did say that’s the slowest speed. 

[Matt S]

As others have said, it's really about surface feet per minute, which is a product of burnisher diameter and RPM, rather than RPM per se. FWIW my burnisher is about 2"/5cm diameter and runs at nearly 3000RPM. I consider this to be at or near to the maximum speed I'd want or recommend. I had to modify my technique to reduce the amount of edge burning and I still burn the odd bit of leather here and there. Further, there are safety implications. Sure burnishes quickly though.

[Mattsbagger]

I’d say practice at different speeds and see what work for YOU. Since different leathers react different.

[LottyAfrica]

Hi everyone! 

Thanks for the feedback.

I've measured the burnisher, it's diameter is just over 4cm (1.57 inch)

Of course I'll be testing and trying what works for me, but as different bench drills have different minimum-speeds, I was afraid that I would buy something wrong (too fast) and therefor would never get the desired result

Does anyone have a similar burnisher - some tips to share?

[mike02130]

I just bought one similar to yours--maybe the same?. I asked the maker what speed is good. I gave him a list of speed options from 180rpms to 3500.  He told me slower is better.  I tried it on some 9 oz veg tan at 180 rpms and that worked well. But I haven't had the chance to try other rpms--yet.  

Don't let anyone get you caught up in figuring rpms to diameter ratios and the like. If you want to go simple you can pick up a used 1/4 to 1/2 HP motor with 1725 or 3500 rpms pretty cheap. Buy an arbor and chuck and you have a good machine.  This set up has a much smaller footprint than a drill press.  Hell, get a double shaft motor, two chucks one with a drum sander the other with the burnisher.  

[bermudahwin]

5 hours ago, mike02130 said:

Don't let anyone get you caught up in figuring rpms to diameter ratios and the like.

The material of the burnisher head, the physical speed at the point of contact with the leather, the type of leather AND the pressure put upon the leather onto the burnisher are all components of 'what you need to sort out what suits you'.

Unfortunately Mike  "the physical speed at the point of contact with the leather" will get you caught up in that. I personally put it all together and try it, raher than working it out, but a large burnishing wheel has a much faster contact area than a small one - watch the inside label versus the outside edge of a vynil disc on a recored player.

BTW, most of my veg tan burnishing I do by hand with a rough rag, but as people of the forum have realised I am a wee bit old fahioned.

Best

H

Edited April 3, 2019 by hwinbermuda