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View Full Version : Wood lathe vibrations. HELP!!!



asheddie
17th February 2012, 06:26 PM
Hello, I'm relatively new to wood turning. I've been given a wood lathe but didn't get a chance to use it for a few months as i was building a new shed. Now the shed is complete I had a go turning some Sheoak. The lathe is much nicer to use than my old, home made job but the new one is a lot lighter than the old girl. when I'm doing the initial turning the lathe wants to vibrate to the other side of the shed, making some nice big scratches in my new concrete:~ It has a spot to bolt it to the floor but i don't really want to put holes in my new slab. I was thinking it would be nice to put some wheels on it and take it to the front entry step so i don't throw so many wood chips around the shed. Can i put some sand bags around the feet or use tie down straps? any suggestions?
Cheers.

RETIRED
17th February 2012, 06:29 PM
Some more information needed.

What brand of lathe? What sort of bench?

Some pics would help as well.

asheddie
17th February 2012, 07:29 PM
Some more information needed.

What brand of lathe? What sort of bench?

Some pics would help as well.

I took these pictures with my phone so not the best quality.


The brand is LEDA and it has a cast iron bed. Don't get me wrong it's still heavy, just not heavy enough to stop the vibrations.

hughie
17th February 2012, 08:06 PM
The brand is LEDA and it has a cast iron bed. Don't get me wrong it's still heavy, just not heavy enough to stop the vibrations

Welcome aboard, not sure if this will help but here goes.

Well at the end of the day vibrations are due to balance issues and every lathe has its range or limitations. As turners we need to be aware of our respective lathes limitations and generally work with in them. I say generally for the most part we often push the envelope. :U

Bolting down your lathe; I rarely if ever bolt any of mine down :o shock, horror! Rather work on adding wieght to the lathe stand and or redesigning the stand its self, if required.

So my question is what are you going to turn thats going waltz your lathe a round the shed? Also you need to have good floor contact on all the lathe feet, no wobbling.



Can i put some sand bags around the feet or use tie down straps?


Definitley :2tsup: look at sand bags, tie downs might be more of a hassle than a help here.



thinking it would be nice to put some wheels


Wheels you might need to look at some quality type with good brakes, no nylon tires. I would go for rubber tires and look at 3" plus in diameter for the wheels, maybe even 6". The bigger dia will have a wider tire and greater load capacity .Try also to place them so the centre of gravity is low as possible.

Heres my previous expierence with a low cost generic lathe. :U
I had something equivelant to a Grizzly G0462 Wood Lathe Without the Digital Readout. With abit of fiddling around and building a new bed etc. It could swing a 12'' lump of around 25-30lbs well without bolting it down and without waltzing around the shed. Prior to this it would have been impossible and somewhat suicidle :o:U Actually mine would have been closer to yours by the look of it.

Avery
17th February 2012, 09:25 PM
As above!

also, you have to look at what you are turning. Some timbers have heartwood and sapwood that are very different densities. If you bolt up a piece of camphor laurel that has a large piece of sapwood on one side, you might chase the thing all over the shed until you have the sapwood off.

Just looking at your photos again, for a lathe of that size with that stand under it, you must be turning a reasonably sized piece of timber to cause the problem.

Sandbags work.

Treecycle
17th February 2012, 09:57 PM
Another thing to watch for is the RPM that you are trying to turn at. If you have a blank in the lathe and it is not round, you need to keep the revs fairly low until trued up. It doesn't need to be very much out of round to create vibration at higher speeds.
As your lathe is a variable speed, you can start off at the lowest speed and slowly increase it until it starts to vibrate a bit, and then back it off a little until most of the vibration is gone.

vk4
17th February 2012, 10:13 PM
Agree with all above, you need to add weight on to the lower shelf, a couple of 20Kg bags of sand will do the trick.

An alternative is to make up a couple of box's/trays to hold the sand , I field this is a better way to contain the sand rather than just in plastic bags.

My 2 cents worth.

Jeff

asheddie
17th February 2012, 11:13 PM
Thanks for the advice, I think one of my problems was how i mounted my timber. I used a face plate with screws but they seemed to come loose and put it out of balance, then it dug into my tool and took a big chunk out the side:no:. I think the problem started with my tail stock, I have a dead centre and found it either burnt a hole from to much friction or was to loose and the vibrations came! i think i will get a live centre, select where the tail stock meets my timber better and put some sand bags around the feet, then try again.
The timber I have is dry Sheoak, pinkgum, redgum, stringybark, blackwood and mallee root.
I've only tried the sheoak so far on this lathe. is that classed as a hard wood? I have lots of Blackwood avalible but want to get a bit better before i practice on it!

Sawdust Maker
17th February 2012, 11:32 PM
Not sure what the problem is ... chasing the lathe around the shed can be good exercise :p

NeilS
18th February 2012, 08:43 AM
I have a dead centre and found it either burnt a hole from to much friction or was to loose and the vibrations came! i think i will get a live centre, select where the tail stock meets my timber better and put some sand bags around the feet, then try again.

Good move to get a live centre. Until then, wax the recess in the wood to lubricate the dead centre.

Add most of your sandbag (or other) weight in the bottom of that cabinet under the headstock (if it will fit under the motor) and some on that bottom shelf.

I've only tried the sheoak so far on this lathe. is that classed as a hard wood?

No, if it's fully seasoned I would class it 'as B***** Hard'.... :D

I'm not sure if it is technically a hardwood, I expect so. But strictly applied the botanical term 'hardwood' can be confusing for us woodturners. For example, balsa wood is botanically a hardwood, whereas as Douglas Fir which is harder than some hardwoods is botanically a softwood.



Welcome to the forum.

Paul39
18th February 2012, 08:54 AM
Nice lathe. Get a couple rubber mats that are sold for standing on concrete, and put them under the ends of the lathe with the feet centered. Get a third for yourself if you get addicted and stand in front of the lathe 4 hours at a time.

Put a 50mm thick piece of timber under the middle of the bottom shelf to make a center leg to the floor.

Fill the shelf with sand bags, buckets of gravel, solid concrete blocks, dead car batteries, scrap steel, etc. You may want to put a piece of plastic or canvas over the stuff on the shelf to make it easier to get the chips out.

The rubber will keep the lathe from scooting on the concrete, and maybe quiet some of the noise of the cabinet, and the weight will hold it in place. 50 Kg would not be too much.

An oiled up dead center will keep you going for a while. If it is put into the waste part of the timber it doesn't matter if it gets a bit hot. Live center is better.

Always start at the slowest speed until you get the corners knocked off the timber. Use #10 screws and enough of them so you don't get a mouth full of spinning timber. Stand to the side when you first turn on the lathe with a new piece mounted. As you turn, stop and check the screws occasionally, especially if you have a catch.

I once had a catch making an interrupted cut on a locust stump that broke two #10 screws, tore out the other two, and the stump flung it self 7 meters into the yard. I was hollowing so I was at the tail stock end.

Have fun!

Treecycle
18th February 2012, 09:43 AM
If I have to use a dead centre I put a dob of grease in the centre hole before inserting the centre. This will stop the burning and wear.
As Paul says, use decent size screws with deep cut threads.

asheddie
18th February 2012, 12:00 PM
I like the idea of the rubber Mat under the feet. I'll try that, and i will make a box for the sand bags to sit in too. I have to go to town this arvo so i will get some bigger screws and a pot of grease! thanks every one for the advice, I'll let you know how i go.

Paul39
18th February 2012, 01:23 PM
I like the idea of the rubber Mat under the feet. I'll try that, and i will make a box for the sand bags to sit in too. I have to go to town this arvo so i will get some bigger screws and a pot of grease! thanks every one for the advice, I'll let you know how i go.

Vaseline, olive oil, cooking oil, mineral oil, etc. Wheel bearing grease is nasty.

Gouge out a hole in the timber, put in a half teaspoon of grease / oil, run the tailstock up tight, run lathe 30 seconds or so check tightness, back out tailstock to barely snug to reduce friction. Add a few drops of oil occasionally it things get warm.

ssajn
18th February 2012, 03:47 PM
Something I didn't see mentioned but important. Make sure your lathe is level.

issatree
18th February 2012, 05:53 PM
Hi asheddie,
I don't believe I saw it mentioned, but have you tested the Spindle, to see that it is not bent. Just use your Tool Rest up close to the Spindle, rotate spindle by hand & see how it stands up to being Straight.

On behalf of A / e, someone out there must have a SPARE LIVE CENTRE, to get away from that dead centre, he is trying to use.
If I had a Spare it would be his, but I'm afraid I don't have one.

orraloon
18th February 2012, 11:35 PM
What all of the rest have said. If it vibrates something is not balanced. The faster the reves then the more vibration. Weight in the legs and something like rubber mats help but any balance and/or alignments issues have to be addressed regardless. It looks to be a reasonable quality machine so I suspect something other than a quality issue. Any wood that is not perfectly round will cause vibration so until it is roughed down to round it will vibrate. The more mass the wood the worse it will be This is to be expected so roughing is done at a slower speed to start with. Rule of thumb is mount wood then spin up. If it dances about slow downto the best compromise. The more balanced the wood gets then the vibration gets less. Does the thing vibrate without any wood in it?
On another note there is nothing wrong with dead centers and the only lube they need is a bit of candle wax scraped on or even soap. No need for grease or oil that will make a mess. I suspect that your problems are the reves were too high as that would cause burning at the dead center and vibrations would be larger. You say a faceplate was used so I think you were turning something like a bowl or heavy in any case. If you are starting out just do spindle work for a while to get the feel of the tools. Faceplate work has some risks so not for the beginner.
If there is a turners club near you then go get some lessons. Just reading your post I have visions of a bad injury.
Regards
John

rodent
29th February 2012, 01:16 AM
? how out of balanced is your wood , does it turn (when lathe is off ) too a certain point all the time if so that's where your out of balance point is .

asheddie
29th February 2012, 04:45 PM
Just a quick update. I haven't got back to the lathe yet, Work has been flat out. I did check that every thing was running true and with out anything mounted on it there wasn't any vibration at all so it was just my dodgy mounting that made the vibrations. Ive just got myself a new grinder to sharpen my lathe tools and look forward to getting back into the shed as soon as work dies down a bit.

Paul39
1st March 2012, 02:19 AM
Just a quick update. Ive just got myself a new grinder to sharpen my lathe tools and look forward to getting back into the shed as soon as work dies down a bit.

Work, the curse of the turning class.

old pete
1st March 2012, 10:02 AM
Hi Asheddie,

Suggest you start by isolating the problem to the machine or to the stock. Very carefully mark up,punch and mount up a spindle blank of say 50mm by 50 mm hardwood. Run the lathe at about 1200rpm. If you have any vibration there then you have a problem that isn't with the stock.

Out of round or differential density across the blank in bowl stock can certainly cause major vibration also front to back dynamic balance issues in the stock that cannot be detected with the lathe stopped may be at play but how about nailing things down a bit before seeking solutions. If you heavily load the stand of a lathe that isn't sitting on a planar floor you will just introduce a new set of problems. Good Luck Old Pete

nrb
1st March 2012, 01:05 PM
Does it vibrate without anything mounted? if it does at max. speed get that fixed first