Why and How? Sanding in Reverse.

[Hilel Salomon]

I've heard many people recommend sanding in reverse mode. Haven't done it yet. On both of my lathes, PM 3520B and Nova DVR, reverse is possible, but I would have to tighten a grub screw in order for the chuck to stay on. The one time I did that, the screw made a pretty big indentation and I'm hesitant to do that again.
What's the advantage of sanding in reverse?
Any way not to mess w/headstock spindle in doing so?
Thanks, Hilel.

[Steve Schlumpf]

Hilel - I use reverse when sanding each and every time. What I find is that the wood fibers have a tendency to lay down - in one direction - when sanding and that if I use reverse as a last step it removes most of those fibers. Real easy way to check on this - after you have your turning sanded feel the freshly sanded wood. Should be extremely smooth when touching in the direction of spin on the lathe - but - when you feel the wood in the opposite direction is feels slightly rough. Using reverse as that last step removes those last fibers and makes it glassy smooth. It does make a difference.

As far as the grub screw marking the spindle - yup, it happens. Won't hurt the lathe - so be sure to tighten it down!

HTH

[Paul Engle]

I do the same as Steve does ..Hilel, up to 600 grit then use brown paper bag both direcitons at about 200 to 300 rpm to burnish / polish the surface before starting the finish . I tighten up my chuck ( no I do not use the grub/set screw unless turning in reverse with a gouge or rough sanding , I have cleared a section on the spindle for the set screw to lock in and filed the thread in that area so as not to gall the chuck etc . works quite well actually especally when rough sanding to 400 grit).

[Ron Lynch]

You can buy brass,nylon or silver tipped set screws from McMaster-Carr. These screws won't damage your spindle or threads.

[Burt Alcantara]

I sand in reverse to flow the dust into the collector and away from myself. If I really want to do a good sanding job, I alternate directions between grits.

[Craig Powers]

is it necessary to reverse if you're using a power sander?

[Mark Pruitt]

I use two methtods of power sanding; a drill, and a Grex pneumatic Random Orbit Sander. This applies to both:

Sanding the outside of a bowl on my 3520B I go in reverse. I have never used grub screws and in over two years have not had a chuck work its way loose. Even if it did, I would catch it long before it spun all the way off the spindle, b/c sanding is done at slow speeds. Additionally, as Burt pointed out, the reverse direction routs the dust directly into the dust port sitting behind/above the workpiece.

The inside of the bowl is another matter. I used to go in reverse there as well, then one day I experimented with going in "normal" direction and for some reason it just worked more smoothly. Less grabbing, and I even noticed that the dust was being more easily thrown towards the port.

So, I guess you could call me a hybrid.

[Steve Kubien]

I never reverse faceplate work. Just reverse the drill/sander. On spindles I do reverse couple of grits. Seems to give a smoother feel.

[robert hainstock]

Hilel,
Another way to reverse sand is to reverse chuck the item. Also you can raise the grain by dampening the piece, (wipe down with a damp rag).. Good luck. :)
Bob

[Mike Minto]

i, too, use reverse sanding to smooth my turnings - also, do you wipe them with water to raise the grain, and sand again? burnishing, when appropriate, is also a wonderful option. mike

[robert hainstock]

i, too, use reverse sanding to smooth my turnings - also, do you wipe them with water to raise the grain, and sand again? burnishing, when appropriate, is also a wonderful option. mike

absolutely. The water seems ro stnd those suckers up so your sander can get at them better. This even helps without the reverseing, but not as much as that does. You read in a previous post about those fibers that stand up, these are what you are after. And once more, I stress "a damp rag or paper towel. I was taought this method in HS shop some years ago for flatwork. :)
Bob

[Jim Sebring]

To keep the grub screw from deforming the headstock threads, drop a #4 buckshot or .177 airgun pellet in the hole before inserting the grub screw.

[cliff smith]

i discovered reverse sanding a while back, couldnt believe the difference it makes.

[Jeff Nicol]

Hilel, I use the 3520B in reverse all the time and have never had the chuck or faceplate come loose. If the mating surfaces of the chuck and lathe are clean and smooth, which they should be that connection will get pretty tight. Like also stated you are normally sanding at much slower speeds than when turning. I have an old Sioux angle drill that I use for power sanding and I put it in reverse while sanding inside the bowl when the lathe is going forward and vise versa when going reverse on lathe, drill is in forward position. Dampening after 400 grit seems to get all the little fibers to stand up and be removed then on to 600 or more or stop right there. Some woods will not have as many tool and sanding marks to remove due to thier hardness or because they are more porous, like oak and ash. The only time I used the set screw it seemed to get tighter and I almost could not get it out of the chuck on the spindle and that was the last time I ever used one, 5 years ago! Just make sure everything is tight.

Jeff

[Bill Bulloch]

My lathe does not have a reverse. Would standing on the other side of the lathe not be the same as the lathe running in reverse??

[curtis rosche]

on the lathes we have at school, i sand with the reverse. it speeds sanding up by a large amount. the first sanding grit is in reverse, the next in forward, the next in reverse and so on. the last grit gets both directions. it works so much quicker. if your faceplate/chuck stays on your lathe tightly without using the special screw, you can sand in reverse with out it. but just be careful. the lathes we have at school dont have a screw or anything to hold the faceplate on. so we just tighten them down first.

[Chip Sutherland]

NOPE. Sit and think about it.:rolleyes:.......

[Mike Minto]

bill, great idea - now if i could only get the math i have to do to balance my checkbook to follow that kind of 'logic' - mike :D

[Hilel Salomon]

Well, I tried reverse sanding and it does help matters. Problem is that I tried it w/a Vicmarc chuck which has no hole for a grub screw and twice the chuck came off. How slow is "slow." If I turn at 375rpm or slower, it can stay on. Otherwise.... Yikes.
Regards, Hilel.

[Steve Schlumpf]

Hilel - I turn with the speed turned all the way down. On the high range on the Jet that works out to around 127 rpm. Slow but it keeps the wood from heating up and cracking. Also, I have seen where folks mentioned switching directions on their drill when sanding. I do that all the time but still find I have to reverse the lathe direction as well.

Hope you get all this sanding stuff figured out! Looking forward to seeing some more of your work real soon!

[Nathan Hawkes]

Well, I tried reverse sanding and it does help matters. Problem is that I tried it w/a Vicmarc chuck which has no hole for a grub screw and twice the chuck came off. How slow is "slow." If I turn at 375rpm or slower, it can stay on. Otherwise.... Yikes.
Regards, Hilel.


Hilel, I do a lot of mildly warped bowls, and natural edge bowls--I like turning green wood. If its just so-so stuff, I turn thick then let dry, but its so much more forgiving to get clean cuts in wet wood that I don't care so much about the warp anymore. I sand at 50rpm, and I wish that the 3520 went lower. Reed Gray has talked about this before at length. Even if it isn't warped that much, I feel like it takes less time sanding really slowly, or even with the lathe stopped. I've actually been at it sanding bowls since about 9 this morning. I find it very difficult to judge when you've gotten all the scratches from the previous coarser grit as you go to progressively higher grits. By sanding with the lathe off, (which sounds like a pain until you do it for a while), I think I actually end up spending less time on an average 12" or so bowl than if I'd spent a couple minutes on each side of the bowl with each grit and the lathe running. The sandpaper lasts a lot longer too. I even keep a crepe rubber stick to clean the paper between inside & outside surfaces. I'm pretty adamant about switching to a new piece between each bowl unless its a very small bowl with little sanding required. Sandpaper is cheaper to me than the time required to remove small scratches left by worn paper....
Sorry, I get a bit off track easily. Anyway, about that vicmarc chuck....Does it have a threaded adapter or is it a direct-thread attatchment?? The reason I ask is because it probably wouldn't be that difficult to put it in a vise on a drill press & tap some threads in the side. Starting this weekend I'm going to be out of town 'til the third, but after that I might be able to help if you're going to be in VA...

[Mike Lipke]

Well, Problem is that I tried it w/a Vicmarc chuck which has no hole for a grub screw and twice the chuck came off. How slow is "slow." If I turn at 375rpm or slower, it can stay on. Otherwise.... Yikes.
Regards, Hilel.

Try making a washer, or maybe two washers, out of a plastic milk bottle, or some other plastic that is a little thicker, and place these between the chuck and the spindle. Tighten the chuck up good against the washers, and you will probably not be bothered with the chuck coming off.

[Ed Heuslein]

I was taught years ago by an old sage to reverse directions with each grit. I've been doing it on several lathes now - starting with an old Shopsmith which I twisted the belt into a figure 8 to get it to reverse. I have never had a piece come off when sanding in reverse. I find that switching the pneumatic drill to between fwd and rev useful depending on what part of the piece I'm sanding. Also, on the advise of Russ Fairfield, for whom I have a tremendous respect, I sand s l o w . Try it - it works.

[James Roberts]

I don't know if this is a good idea or not but I have a JET 1220 and I loosen up the motor and liftit like I was changing belt (speed) settings then put a half twist in the belt which causes the spindle to go in reverse. I only do it for the last grit and raise the grain with a damp towel. Has anyone else tried this and is this a big no no?

Jim

[James Roberts]

I forgot, I only do this on the lowest speed setting.

[Scott Hackler]

I sand using reverse as well. I have been sanding with the same grit in both directions and then move on to the next higher grit.

Lately I have been using my new right angle drill and 3" pad. Holy moly does that help speed up the sanding process and it makes a better finish. One note, I usually sand a the same turnng speed (around 1000-1400 rpm), unless its pretty out of round and too thin to turn true again. Then I slow it down to 300-600 rpm. So far so good, but maybe I should try the lower speeds all the time.

Oh and I almost forgot. No set screw equals high pitch wining sound, a second of "what the heck is that" and the chuck flying off the lathe. Mine is cranked down hard now. (I dont ever remove my chuck)

[Tim Thornton]

My lathe does not have a reverse. Would standing on the other side of the lathe not be the same as the lathe running in reverse??
Unfortunately, standing on the backside will reserve the direction the wood is coming at you (will be coming up instead of down), but the grain will still be layinging down in the direction the wood is coming at you. It may be that the best way you may have is to stand where you normally do, and just concentrate on putting the pressure on the side of your power sander pad that turns against the grain, and manually turn your piece.

[Jeffrey J Smith]

Tim - did you realize this thread is over a decade old? I know I’m using my isolation time to catch up on email, but that seems extreme.

[John K Jordan]

Tim - did you realize this thread is over a decade old? I know I’m using my isolation time to catch up on email, but that seems extreme.

Some concepts are timeless.

I sand spindles in reverse, or rather, alternate the direction and further alternate circular sanding with sanding with the grain by hand. Platters and bowls? I haven't power sanded in a long time. I use negative rake scrapers to remove most tool marks then remove the piece from the lathe and scrape smooth with hand scrapers then sand by hand.

[Alex Zeller]

My Vicmark chuck came with a plastic washer that goes between the chuck and spindle. I've never had it loosen up as long as I snug it down by hand. I do reverse sand because it throws the dust right at my dust collection chute. But I don't bear down hard while doing it and find that sanding perpendicular to the rotation of the lathe much more effective but not as easy.