A Couple of Questions

[smidsy]

Hei Guys,
Just been playing with this monster block of jarrah that I refered to in my post a week or so ago.
I managed to hack it down to a point where is it is roughly round and will turn on the MC900 without having to resort to outboard turning.

The wood is now about 300mm diameter, about 200mm long and while still out of balance seems better than before.
Still too much for the MC900?

Also, the minimum speed of the MC900 is 500rpm. Has anyone ever thought of attaching a drill (or even an air ratchet) to the other end of the shaft so you can turn the shaft at a slower speed - obviously you couldn't turn anything but a slower speed would allow you to check the balance of timber.
Cheers
Paul

[rsser]

Re the size question Paul, I'd give it a go. Maybe give the hunk a good push before you hit the start button; maybe expect some belt slippage or damage.

Chk the extent of vibration (you've weighted your stand?) - if the gouge keeps bouncing off the tool rest or the lathe starts walking around the workshop, time to stop ;-}

Re your other question: good lateral thinking. You could always turn it into a pole lathe.

[JackoH]

What rsser said above. However if it is still impossible to turn on your MC900, would you be able to find a turner with a heavier lathe to do the initial rounding. Your local club perhaps? Failing that send it over to me and I will balance it for you on my VL 300. :cool: (You pay freight. :rolleyes: )

[macca2]

Paul, I only have a Woodfast 280 with a 300mm swing, and a .5hp motor but I have tacked similar pieces of jarrah. ( not very often) The lathe is mounted on a heavy Jarrah stand and bolted to the floor, and still shakes the ..... out of the place when you start.
Slowest speed, tailstock up tight, stand to one side when you start the lathe, and then use a well sharpened heavy roughing gouge. Dont forget the safety gear.
Good luck and show us the end result.

Macca

[macca2]

Paul
This is a vase?? turned from an old post.
It is approx 280 high and 260 wide in its finished state.
This was turned on my Woodfast280
Macca

[smidsy]

Hei Guys,
Just spent the morning in the shed.
What I ended up doing was enclosing the lathe stand up to the braces (about 350mm up) in timber and filling it with gravel for ballast.
It would ideal to bolt the lathe down but it's across a roller door and has to be shoved to one side from time to time, I thought about sand for ballast but I use a compressor to clean the lathe.

Haven't tried any turning with it yet but I'll let you know how it goes.

In regard to being able to run the lathe at a slower speed, what I thought of doing was run a thread tap up the end of the shaft, run a bolt in to the thread and then use a cordless drill or air ratchet on that bolt to turn the shaft. The bolt could be removed when necessary to put a push rod up the shaft.
As I said in my other post, you couldn't turn with it but I'm thinking it would allow you to turn the shaft at a considerably slower speed than the 500rpm minimum to see how bad an out of balance of peice will be.

Something I noticed on the Vicmarc site is that they sell an electronic variable speed unit that can be retro-fitted to other lathes - anyone know what these are worth.
Having had bit of a nose around I don't see any point in upgrading the lathe unless I went for a Vicmarc and that's something I'll never be able to afford.

That's a gorgeous vase Macca - gives me someting to aim for.

Cheers guys
Paul

[macca2]

Paul......the electronic variable speed control is in Carbatec catalog and I seem to recall from a previous thread Joe was talking $1000.
Do a search under "variable speed control" and you should see what others had to say.

Cheers Macca

[smidsy]

Hei Macca,
I just looked in the Carbatec paper catalogue which lists the price as POA and it's not showing at all on the C/tec website - note to Carbatec, your site is costing you business, go look at Timbecon's site and then do something with yours.

Timbecon sell a Sherwood lathe with electronic speed control, but for $900 it's only 75mm more bowl capacity than the MC900, and the lowest speed is only 80RPM less than the MC900 so I don't think it's worth it.

Cheers
Paul

[rsser]

K, pole lathe or equiv.: wrap something like a snatch strap twice around your faceplate edge (if it'll fit) or part of the lump you're not about to shape. Have a good friend, mistress or wife run away from the lathe with the length that will turn the lump in the right direction while you shape with gouge or pref arbortech.

If promising, repeat. Often I'd think!

That might be easier than setting up a springy sapling in your workshop ;-}

Cheap, low tech solution - suits a colony of Australia don't you think?

[smidsy]

Hei Ern,
I'm ahead of you mate - already tried it with a length of rope like the old pull cord mowers.
The problem is that I'm on my own so it was hard to tell if the rocking of the lathe was due to the unbalanced wood or me pulling on the rope.

Cheers
Paul

[macca2]

Yeah Paul, the same lathe is in the Carbatec catalogue. Different colour but same species for $995.
Cheers Macca

[rsser]

Hei Ern,
I'm ahead of you mate - already tried it with a length of rope like the old pull cord mowers.
The problem is that I'm on my own so it was hard to tell if the rocking of the lathe was due to the unbalanced wood or me pulling on the rope.

Cheers
Paul

:D :D :D :D :D

[Ozartisan]

Sorry guys - have to put in a plug for the ultimate fix for getting out of balance blanks tamed...
Hang em on your DVR - start at 100 revs & go up from there!!!
:D :D :D :D :D :D

[rsser]

Bah, that's the easy way out.

You'd deprive Paul of all the fun he's having. :)

[smidsy]

Hei Guys,
I gave it a try this morning, still a lot of vibration and probably the first time I've been scared on a wood lathe but all well in the end.
The blue metal in the base definately dampened things down a lot, although now the vibration is being absorbed by the frame so it will be interesting to see how long that lasts.

Attached is a couple of pics, one of the lump of wood, and one of what I've done to the base - the enclosure of the base is probably the roughest thing I've done in the shed for a while but it serves a purpose.

Not sure what I'm going to do with this wood, it's now fairly round and balanced but there's some end grain in the edges so I'll have to think about what to do with it - ideas?
Cheers
Paul

[Gingermick]

Yeah mate. with that end grain it will be no good. better send it up to me to safely dispose of.

mick

[gatiep]

Paul,

You can always hang it off the VL-175 at the club which goes down to 62 rpm!

:)

[smidsy]

Hei Joe,
I've actually got it fairly well balanced now, although the 175 at Liddlelow was an option. The problem I have is that my lathe has the 30mm shaft but the 175 is only 25mm.
The problem with swapping face plates is that you can never (I can't anyway) get the balance exactly right after I change face plates - can I get an adapter to go from 30mm to 25mm so I can use my face plate on the smaller shaft.

Is this block of wood going to be too big for my VM100 chuck?

Cheers
Paul

[rsser]

Hmm, k, can see the vibration dampening thinking in no. 1; my take on that was to put a shelf on the lower cross braces and 80kg of concrete bags on that - so, pushing down rather than damping, but maybe with the same effect.

End grain ... hehehe .. well, no seriously; suggest small cuts with min. tool overhang. Otherwise, it's 60 grit all the way.

I'm a fan of curved rests and small gouges.

To avoid flexing and the resulting tear out: stagger your cuts as you go down; support the outside with a couple of fingers from your free hand (try gouging with one hand, not as hard as it may appear); or build a bowl steady like the one I've posted. Or leave the wall thick. Bugger even thickness - do an ogee, swim against the trend!

[rsser]

"Is this block of wood going to be too big for my VM100 chuck?"

Not for outside shaping with tailstock.

What jaws are you going to use?

How heavy is this lump?

For hollowing, you may have to use the tailstock, leave a stem, and then cut that off and sand back at the end of the job.

Edit: other option is to leave a thick foot, and fix this to your faceplate. When finished hollowing, remove and manually chisel and rotarily sand it away. (Further edit: Or better: use a glue block.) Or build a vacuum chuck. Good tool; do a google; lots of designs on the web. An old vac cleaner is enough.

[smidsy]

Hei Ern,
The only jaws I have for my chuck for this sort of work are the stock ones that came with it.

In regard to holding the lathe down, I never thought about the vibration aspect and used the blue metal for the weight but I suppose when you think about it that something loose would absorb from of the vibration.
Cheers
Paul

[rsser]

Hopeful, with the standard jaws Paul. They just don't exert enough hold on a piece of your size; even if you don't pull it out with a catch you'll get flex - and that means end-grain tears.

[macca2]

Paul, that is one large lump of Jarrah. Can't wait to see results of your hard work.
Good luck
Macca

[gatiep]

Paul,

I cannot reply to your pm as you have no space left. Delete some of the old pm's you have in the folder so that I can send my reply.

The blank is big but not impossible to turn with the VM100 on a spigott and the MC900, but go gently don't dig in, rub the bevel, otherwise no matter how you hold it, it will bounce on the concrete. Maybe turn it on the faceplate and tailstock. Once round and fairly shaped, remove faceplate after marking the center, then turn it between centers and put a 10 mm long spigot x 45 mm on it, slightly bevelled like the inside of the jaws. Try getting it so that at max clamping pressure, the jaws are as close to a perfect circle as possible..... that means about 1.5 mm gap between the jaws. If the spigott is too big, the jaws only clamp on the edges which is why people have failures with standard jaws and then resort to shark jaws. With each action we take it pays to take technique into account.
I am amazed that the VL175 does not have a 30mm x 3.5 spindle, but then some old fossile at the club spent a lot of money to have adaptors made to turn the Woodfasts they have there to 1" x 8 ( or 10 ), although they have more m30 spindles than other and more than what they have chucks. Some people cling to the imperial system although almost the whole world uses metric...........same applies at the club. Spent hours showing them how much money they were going to waste with those adaptors, rather than changing inserts on the chucks. However that is history.

Go gently with that chunk, all blanks have the potential to go flying.........the big ones just make a bigger dent on landing.

:)

[smidsy]

Hei Joe,
I just cleaned out my PM's so you can try again.
I'm not sure what the reasoning is at Liddlelow for going to 25mm, I normally grab one of the 30mm lathes and toss the adapter in the draw so I can use my chucks - plus if I have something that needs a face plate I usually mount it at home.

I'll let you know how I go with the block of jarrah.
Cheers
Paul

[barnsey]

G'day Paul,

I've done what you are trying to do on an MC900.

I've chased it around the floor with seriously out of balance pieces :o

I've had really out of balance pieces cause the lathe to come to a point where it wound up against the wall behind it - and not me luckily :eek:

I've also had them fly off the lathe - without terminating injuries - luckily :rolleyes:

Most of your advice has come from people with much heavier lathes, my approach is to try and remove a little material with whatever you have available. You know it is out of balance so overcome it. Bandsaws are great but you can achieve results with the table saw, planer - use your imagination.

There comes a point where the piece you want to work is THE out of balance piece. Gentle approach, light cuts, sharp tools, BE BLOODY CAREFUL and you can get to a point where you have more control.

Lathe speeds?? You already know the answer to that - thats what on/off switches are for! ;)

I'm not advocating a gung ho approach but sometimes the best results come from using all your talents to achieve something you are proud of. Bit like driving a car - you need to know what your limits are - we can't all handle 10 tenths.

FWIW

Jamie

[smidsy]

Hei Jamie,
What people need to remember is that what we are doing is inherantly dangerous in itself. If you try to be gung ho in this game you will get yourself hurt or worse - especially when dealing with large lumps of jarrah.

I think the worst I've had was when I started turning a block without using the tail stock and managed to bend the screw on my Vicmarc chuck when the wood let fly. Fortunately the wonderful people at Vicmarc sent me a replacement screw without charge - if that sounds like a blatant plug it is lol.

For this lump I ended up using a power plane to carve it fairly round - I want to get a carving tool for the angle grinder but I want a good one so I need to wait for some cash.

As for lathe speed, the MC900 has it's limitations in that it only goes down to 500rpm but you do what you can with the gear you have.
Cheers
Paul

[ubeaut]

Smidsy - All I can say is, "Don't come crying to us when you break the lathe or yourself."

The MC900 lathe obviously isn't equiped to handle such work. You might get away with it this time but you won't continue to. Those lathes were never designed to be used for anything much more than basic spindle turning and a bit of light bowl work. You are really pushing the envelope.

Personally, (on a lathe like that) I reckon it is an accident waiting to happen. I hope it doesn't for your sake.

Cheers - Neil :rolleyes:

[rsser]

"I am amazed that the VL175 does not have a 30mm x 3.5 spindle" ... may have missed something in the PMs, but it does come with this standard in Oz.

[barnsey]

Personally, (on a lathe like that) I reckon it is an accident waiting to happen. I hope it doesn't for your sake.

Cheers - Neil :rolleyes:

Neil and others,

I agree with your sentiments. I've had 3 stitches in the brow and the biggest internal bleed in the arm I've ever seen from stuff coming out of an MC900.

And it wasn't the machines fault once. I just pushed it too far. Naive, dumb or just plain stupid - probably all 3 in varying situations.

Bit like driving when I first started out - need to find out how far you can push it to be able to work out what the machine will or won't do. All the above apply again :eek:

As a result of that experience I'm sure we've all extracted something from a machine that was more than anyone could have reasonably expected - don't you just love that feeling - You did it!! :D

Now as I said previously I'm not advocating a "gung ho approach", merely that extra ordinary things can be done with the ordinary, it just takes super ordinary effort, patience and determination. I prefer that advice, as does gatiep to that which suggests you really need a top of the range machine with whatever sized spindle. The fact remains.

I've seen lots of examples of it here and have wondered how they could do that with a lot less eqipment I may or may not have. I was merely trying encourage Paul in his endeavours rather than fault the equipment he was using. Skills, within reason, will overcome the deficiencies elsewhere.

That bloody soapbox again :o

Paul - hang in there pal - you'll get there.

Jamie

[smidsy]

Hei Guys,
I think in hindsight that this lump of wood was at the limits (possibly even over) of the MC900, although it has been an adventure and a learning curve.

I will be taking on what I learnt with this from both the turning adventure and the feedback here, and I think in future I will be grabbing the Vicmarc 175 at my club for stuff this big.

Attached is a pic of the rough turned blank.

Cheers
Paul

[macca2]

G'day Paul. Nice looking piece of Jarrah. How dry is it. How is it mounted on the headstock. Faceplate or Screwchuck.
You have done the hard stuff, it should all be downhill from here.
It should look great as a finished bowl.

nil bastardo carborundum

Macca

[smidsy]

Hei Macca,
For rough turning these days I tend to use the face plate - nice and easy to run in 4 screws with the cordless drill.

The wood came from a Jarrah tree that came down in November - I heard about it through mulchnet and was able to score a trailer load including 3 slabs of 600mm diameter. I could have got more with a larger trailer.

I'm going to cut the slabs soon, I think I'll get about 7 or 8 more blanks of a similiar size by the time I cut round some ant holes.

Cheers
Paul

[gatiep]

Hiya Paul,

Congratulations mate. You've done the most difficult/dangerous part. Now it's for the shaping and hollowing!

A comment about the fact that the tailstock quill that is wound out pretty far........keep it extended as short as possible in all cases. Some reasons: In this instance you put a lot more stress on the tailstock due to leverage/moments than is necessary. By winding out the tailstock far, it increases any error that the lathe center height/ alignment may have. While turning pens and other small items between center the above is not a problem, but when face plate, screw chuck or scroll chuck mounting the work, the alignment is critical.

Anyway, take it slow and easy and you'll succeed with this blank!

:)

[smidsy]

Hei Joe,
It doesn't look it from that angle but the tail stock is as close to the work as I could get.
I had about 5mm clearance between the bed and the work, I tried putting the tool rest behind the tail stock but didn't have the reach so I had to wind out the quill that far for the tool rest.

The next step is to carve out the inside so the walls are about an inch thick and then let it dry some more.

Cheers
Paul