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Rod
5th June 2001, 06:01 PM
Does anyone have any experience of the benefits of reversing the direction of rotation of the lathe motor as an aid to sanding. Would appreciate any comments based on experience.

Thanks, Rod

Chris Longworth
5th June 2001, 07:53 PM
Very good question Rodd.
I’ve thought about it but haven’t tried it as yet.
I too would be interested in any feedback.
Chris .

Iain
5th June 2001, 08:53 PM
I am not a turner but would it have something to do with the 'tool' being pulled away rather than 'pushed' and grabbing thereby reducing the risk of injury?

Shane Watson
5th June 2001, 11:21 PM
I'm not a turner either, but have heard about this process. From what I undestand is that by reversing the rotation while sanding will pick up th grain that has been 'laid' over from the tools while cutting. This apprantly gives a much better finish with little risk of the grain raising...... Probably got it all wrong, but hey I did say I wasn't a turner.... The Symtec in the workshop is testament to that http://ubb.ubeaut.com.au/ubb/wink.gif.... http://ubb.ubeaut.com.au/ubb/eek.gif

ubeaut
5th June 2001, 11:47 PM
This used to be done from time to time, I even have a very old lathe motor with a reversing switch on it for just that purpose. The theory is that the forward rotation of the lathe will bend the fibres of the timber to the rear upon sanding. Reversing the lathe reverses the sanding action thus eradicating those bent fibres.

Oh yeah!! The thoery never really figured out that the fibres were then bent back in the opposite direction, etc. etc. etc. Unfortunately abrasive paper is non selective and not only sands the bent bits but also the timber it is attached to. Strange unforgiving stuff.

With modern abrasives this method is hardly needed. If you use a Rotary Sander (http://www.ubeaut.com.au/) especially on bowls etc. it is never needed.

If you do decide to try this antiquated idea be very aware that it is EXTREMELY DANGEROUS especially if done on bowls etc. unless you have a way of fixing the chuck to the drive spindle. If not you will more than likely wear the bowl when it flies off the lathe because you are running it in the UNDO direction. http://ubb.ubeaut.com.au/ubb/eek.gif

Common sense usually prevails but not always.

Buy, and always use, GOOD ABRASIVE PAPERS and you should never need to do the reverse thing.

Iain - Not only would it reduce the risk of injury from the tools, but it would completely eradicate it, as the tools will not cut if the timber is revolving away from the cutting edge. http://ubb.ubeaut.com.au/ubb/wink.gif

Useless trivia. http://ubb.ubeaut.com.au/ubb/confused.gif The reverseing motor was also used on some lathes for bowl work, but only when the lathe had the right thread setup. This was good for outrigger turning and enabled the turner to work on the left side of the work rather than the right. This method was often employed by left handers so they wouldn't be always working across their body.

Hope this is of some help.

Cheers - Neil http://ubb.ubeaut.com.au/ubb/smile.gif

PS You will notice I refer to ABRASIVE PAPER and not Sand Paper. If you are using sand paper STOP IT NOW!!! Or you will surely go blind (get my drift?). http://ubb.ubeaut.com.au/ubb/tongue.gif

[This message has been edited by ubeaut (edited 05 June 2001).]

JackoH
6th June 2001, 01:12 PM
Spot on Neil (as usual). Get uouself a Rotary Sander and a supply of discs & allyour problems are solved. Honest!
Regards John H.
http://ubb.ubeaut.com.au/ubb/biggrin.gif

Steve Walkom
6th June 2001, 01:48 PM
Speaking of the Rotary Sander, how does it compare with the drill mounted foam pad/velcro type? Can you use the smaller drill mounted pads, etc, on the Rotary Sander?

Chris Longworth
6th June 2001, 10:30 PM
Thanks Neil.
I do use abrasive paper but haven't used the rotary sander. I will purchase one at the Sydney show.
Chris.

ubeaut
7th June 2001, 12:20 AM
Have a look at the site if you haven't already done so. CLICK HERE (http://www.ubeaut.com.au/rotary.htm)

There is little or no comparison between the Rotary Sander and those used in a drill. About the only thing the same is that they both look alike and use similar sanding disks.

That is where the similarity ends. The Rotary Sander is driven by the timber rotating in the lathe, because of this it is working in sympathy and unisom with the timber. The drill driven pad on the other hand is always at odds with the work piece, working against it rather than with it This is not the case of the Rotary Sander.

Because the sander works with the timber there is no trace of sanding marks on the work as they are completely eradicated by the action of the tool. The fines grade of abrasive to come with a kit is 320 grit, this gives a finish that looks and feels more like what you would expect to get from about 800 grit. You can cut and use finer grits but there is very little difference in the cut after 320.

Sanding the outside of a 200mm bowl from 80 grit through 5 grits up to 320 takes approximately 2-3 minutes initially and can be done in well under 2 minutes once you get the hang of it.

Sanding disks on the rotary sander will out last the drill ones as much as 10 to 1 or even more. In our demo's of the tool we can sand the equivalent of about 20 or more 200mm bowls with one set of disks. These demo's are usually done in pretty hard timber which is much more wearing on the abrasives.

The smaller pads are not needed and indeed would not work as the Rotary Sander is made to the optimum size to work on all sizes of work from 1 metre diameter platters down to a 100mm diameter bowls The smallest we have done is a 100mm inside diameter and it worked a treat.

I have used it in spindle work down to 20mm diam with excellent success. Although common sense comes in to play with the spindle work as there is only so much you can expect from the tool. It is not designed to sand beads or coves etc.

At around $60 the Rotary Sander would have to be the best valued, purpose built tool for woodturning that ever there was.

By the way we only sell them at the Woorking With Wood Shows on behalf of Vic Wood. It is not one of our products, just one of our most used tools. I cannot recommend the Rotary Sander highly enough. http://ubb.ubeaut.com.au/ubb/smile.gif

Cheers - Neil Ellis

PS Blatant advertising. If you use EEE-Ultra Shine (http://www.ubeaut.com.au/eee.htm) after the 320 grit you will get pretty well the ultimate sanded finish. Around 3-4,000 grit for an extra 30 seconds work. http://ubb.ubeaut.com.au/ubb/biggrin.gif

jclucas
12th June 2001, 02:39 AM
Wow I'm going to have to try one of those sanders. I've been a power sanding fool for years. I do a lot of spindle work and it's easy to sand in the opposite direction. Just flip the spindle end for end. As someone said earlier I don't find it necessary very often but sometimes on wood that has a tendancy to leave sanding marks I'll give it a try. It seems to help but most of the time is not worth the trouble. John

CameronPotter
13th January 2006, 03:57 PM
Hi all,

while looking about at gouges, I also noticed a few nice looking finishing products.

The rotary sander looks useful, but what are people's experiences on using it with spindles. I suppose that it is of limited use. However, it looks good for bowls.

One thing that I am struggling with though is the concept that you can stop sanding at 320 grit, then go straight to EEE-Ultra Shine. My experience from buffing metals seems to suggest that you need to sand down to a certain level, then buff using an abrasive polish (such as tripoli).

This makes sense to me as the polish is essentially a form of abrasive itself. How could something leave a 3-4,000 grit finish when you have applied it to a 320 grit finish (unless you apply it for a LONG time).

I trust that it does work - as that is what people say, but I would like to know why.

Cheers

Cam

Skew ChiDAMN!!
13th January 2006, 11:49 PM
The rotary sander looks useful, but what are people's experiences on using it with spindles. I suppose that it is of limited use. However, it looks good for bowls.

I also use one on the bodies of my goblets, although not on the stems. I've used it on spindles with long sweeping curves, but can't see enough difference to matter.


One thing that I am struggling with though is the concept that you can stop sanding at 320 grit, then go straight to EEE-Ultra Shine. My experience from buffing metals seems to suggest that you need to sand down to a certain level, then buff using an abrasive polish (such as tripoli).

This makes sense to me as the polish is essentially a form of abrasive itself. How could something leave a 3-4,000 grit finish when you have applied it to a 320 grit finish (unless you apply it for a LONG time).

I'd imagine that at least part of it is the timber's fibre size. With some coarse grained timbers it's pointless sanding beyond a certain grit as the open grain is larger than the particle size. No matter how much you polish a cheese-grater, it'll always have holes in it.

Another part of the picture would be how well the polish also functions as a grain-filler. A bit like putting a plaster render over a concrete wall.

TTIT
13th January 2006, 11:52 PM
I'll have to try one of these Rotary sanders because I've tried going from 320 and even 400 grit straight to Ultra-Shine and have not been happy with the results. At this stage, I still go to 800 or 1000 grit for most Aussie hardwoods before applying Ultrashine or Scandinavian oil.

CameronPotter
16th January 2006, 08:33 AM
Thanks Skew.

I will wait until I get my bowl turning sorted out before invetigating the sander further, but the ultra-shine might be worth considering.

Cheers

Cam

rsser
16th January 2006, 07:49 PM
Hey Rod,

Sometimes you get interlocked grain in a piece, or soft or furry grain, and anything is worth a try.

(The following is not informed by experience with the Vic Wood sander; but Neil is the guru and like an earlier poster my interest is engaged; I'm a power sanding man like Richard Raffan, but any other resemblance is unintended and completely coincidental, inc. the loss of head hair).

Reversing can help, and yes, make sure the chuck doesn't unspool. My Vicmarc has a collar on the handwheel that can be removed and mounted on the other side of the spindle to ensure this doesn't happen.

Sometimes I power sand with a 1" wheel with the piece stationery, to get out chips etc.

Sometimes I have to hand sand (yeah, seriously antique), and sometimes even then only with fixing furry or punky wood by using sanding sealer or old fashioned water or superglue. [Edits in this para btw].

Sometimes changing the direction of hand sanding along with swelling the grain with water is the only thing that will work.

There are no silver bullets with 'interesting' grain.

hcbph
17th January 2006, 05:04 AM
Rod

I do primarily spindle work and I do use reverse directional sanding at times and there is a use for it. Biggest reason is the wood itself. Some wood does tear or pull fibers while turning, and this can help at times. Though I don't have the room to work off both sides of the lathe, I've heard at times turning in the reverse direction may product cleaner turnings at times.

I don't know if I'd try it with either a face plate or chuck mounted unless there was absolutely no way it could back itself off the lathe. Little chance of that with a spur center, but definitely worth consideration.

Paul

RETIRED
17th January 2006, 09:36 PM
Rod

I do primarily spindle work and I do use reverse directional sanding at times and there is a use for it. Biggest reason is the wood itself. Some wood does tear or pull fibers while turning, and this can help at times. Though I don't have the room to work off both sides of the lathe, I've heard at times turning in the reverse direction may product cleaner turnings at times.

I don't know if I'd try it with either a face plate or chuck mounted unless there was absolutely no way it could back itself off the lathe. Little chance of that with a spur center, but definitely worth consideration.

PaulIn spindle work you can "end for end" the piece to turn in the reverse.

All my lathes have reverse switches (yes, even the brute) and it is invaluable sanding big stuff.

ptc
18th January 2006, 09:39 AM
I have the Rotary sander,
Best thing since the mouse trap.

Hand sanding Sanding at the front the work is running down from you
sanding from the back its running towards you .?

RETIRED
18th January 2006, 08:04 PM
Hand sanding Sanding at the front the work is running down from you sanding from the back its running towards you .?

Question or statement?:D