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fozz
14th October 2011, 04:04 PM
Gday folks,

Not being a mathematical genius, engineer or whatever it takes to work it out, I could really do with some help to work out what speed a series of pulleys will make.

I've googled pulley ratios and gear calculators and such and found a few but they are not making alot of sense.

I have a drive pulley thats 47mm and V belt design that goes to a middle drive shaft that has a 134mm v pulley at one end and at the other end of the shaft is a flat belt 3 pulley block where the pulleys are 144, 108, 72 then the headstock shaft with another flat belt 3 pulley block where the pulleys are 72, 108, 144.

The motor I have runs at 1440 RPM.

If anyone could help me with this it will be greatly appreciated.

Ross.

RETIRED
14th October 2011, 04:53 PM
Your speed at the headstock is 144-72 (1010 RPM). 108-108 (505RPM), 72-144 (252RPM).

The actual shaft speed of the jack shaft is 505RPM

These figures have been rounded down to the nearest whole number.

fozz
14th October 2011, 05:22 PM
Thanks very much for the information, much appreciated.

Would you say those three speeds are abit slow for a wood lathe or would I be better off having two or three different size V pulleys for the middle shaft??

The reason I'm asking is I picked up an old wood lathe about 2 months ago and have been slowly reconditioning it.

RETIRED
14th October 2011, 08:27 PM
Thanks very much for the information, much appreciated.

Would you say those three speeds are abit slow for a wood lathe or would I be better off having two or three different size V pulleys for the middle shaft??

The reason I'm asking is I picked up an old wood lathe about 2 months ago and have been slowly reconditioning it.I would say too slow but it depends a little on the bearings.

If it is flat belt drive it may only have thin bronze bushes.

A pic of the headstock would be handy.

I will work out the speeds shortly for you.

powderpost
14th October 2011, 08:48 PM
Would be excellent for chasing threads... :D
Jim

Sawdust Maker
14th October 2011, 08:54 PM
What
you're restoring an old lathe and not showing us any wip photos :o :~

fozz
15th October 2011, 09:40 AM
OK OK OK, i knew as soon as I started this thread I'd be asked for pictures. Too late tonight but i'll post some tomorrow.

I picked this lathe up about 2 months ago from a place in Rosebud. Apparently the lathe belonged to the previous owner of the house and he made toys with it.

The head stock, tail stock and banjo are all very substantial castings. The head stock shaft sits in 2 brass bushes about 6mm thick and about 50mm long. The tail stock shaft has 1 brass bush of similar size and all 3 bushes have a grease nipple and grease cap tapped into the casting above them. Screw to cap down and more grease is pumped into the bush/bearing.

I honestly dont know how the guy turned anything on the lathe the way it was set up when I first got it. The frame of the lathe had been put together from old fence rails and posts, and what looked like an old packing crate.

The first thing I did was discard the frame and make a new one out of ply and aluminium. Then I pulled all the moving parts apart, had to let them soak in the parts washer for a week before the built up grim softened enough then polished what was needed, removed the rust, repainted the castings and then reassembled everything.

The original head shaft was solid and had a thread nearly 50mm in diameter with about 5 threads an inch that 2 faceplates attached to. I've modernised the drive shaft by having it bored, a morse 2 taper added and the thread changed to accept my chuck.

The first picture shows the middle shaft, the second the V pulleys I have to use. If I use the pulley on the right that fits straight onto the shaft and gives me the first set of speeds that kindly worked out for me. The second pulley on the left is 2 pulleys in one, the larger diameter is 98 and the smaller diameter is 72mm.

The rest of the pictures show the different parts and the frame/cabinet that make up the new lathe.

If this works how I hope it will I'll have a wood lathe that will turn a metre+ between centres and it will allow bowls up to 500mm in diameter.

orraloon
15th October 2011, 10:37 AM
Hi fozz,
That looks like a nice find. I like your sliding bed design too. Looking forward to seeing the finished item.
Regards
John

hughie
15th October 2011, 11:03 AM
Well its all there, with bronze bearings you have to keep the lubrication up to them no matter what. If your able try and install some sort of automated system, some of the old time reservoir type with the wicking setup would be ideal.

Delta International Sales (http://www.greasemax.com.au/) this sort lubes as you use the lathe only


scroll down through the doc for info
http://www.conbear.com/dc/ALEMLUBE%20-%20Sept%202010%20Master%20Catalogue%2072%20page(1).pdf

fozz
15th October 2011, 11:13 AM
Hughie, thanks for the pdf, some very interesting reading.

On the matter of grease, the caps on the lathe hold about 3/4's of an inch by an inch of grease in each one. What sort of time should that grease last, i.e, 5 minutes, 30, an hour ?

Sawdust Maker
15th October 2011, 09:19 PM
Hey that looks great - nice restoration - thanks for showing us :2tsup:

fozz
17th October 2011, 10:04 PM
Gday folks, did a quick trip down to 's sunday morning for a coffee, bit of BS spin and some help.

Thankyou very much , after a chat and a gift I came home, did abit of machining on the metal lathe and now the reco wood lathe not only has a modernised head stock but now has a live centre for the tail stoke.

I am one happy chappy!!!!!

The next job is to work out the mounting for the motor and pick up a couple of V belt pulleys and belt to suit and flat belt and the lathe will be ready to fire up. :)

Paul39
18th October 2011, 06:36 AM
The next job is to work out the mounting for the motor and pick up a couple of V belt pulleys and belt to suit and flat belt and the lathe will be ready to fire up. :)

For the flat belt get a serpentine belt as used by modern auto engines.

Leather is very authentic, and expensive. Folks with flat belt metal lathes use serpentine belts because they transmit more power without slipping, and do not have the clack, clack, clack of the metal splice of a leather belt.

Check with your mechanic about a free used one removed from a car. 25mm will transmit 1 HP. They can be spliced with a skived joint and CA glue for plastics.

You could always buy the right length new, not that expensive.

If you need more info, send me a PM with your email address and I will send you a pdf with full instructions.

Neat lathe, the low speeds will be nice for roughing out 500mm bowls.

When working, occasionally feel the bearing caps, when they get warmer than comfortable, add grease.

fozz
21st May 2012, 01:25 AM
Hi folks,

I know this has been some time in the works, others things became more important so the lathe got pushed to the back of the list.

I've since made a 3 cog pulley out of timber to match the metal one I have, didnt have a 25mm drill bit or boring bar to make the metal pulley fit the jack shaft.

The head and tail stock now line up within a gnats whisker, just need to work out how to mount the motor and jack shaft and fingers crossed it'll be a goer. :)

fozz
24th May 2012, 09:17 PM
Well Folks,

Had a productive day today. The jack shaft is now fixed in placed with the turned 3 cog block. The flat belt has been cut and roughly joined for now, will see if that does the trick.

I do have another flat belt, this was I cut to size but I forgot to cut both ends hence the daggy holes that show up in the pic. I dont know if wire is the go but the belt originally was joined with leather strip and wire.

One thing I was wondering about, does the leather belt need to be oiled or not cos I think its as old as the rest of the lathe.

Tomorrow I'll mount the jack shaft and motor to the lathe and hopefully fire the monster up, fingers crossed.

Paul39
25th May 2012, 03:02 AM
Well Folks,

Had a productive day today. The jack shaft is now fixed in placed with the turned 3 cog block. The flat belt has been cut and roughly joined for now, will see if that does the trick.

Tomorrow I'll mount the jack shaft and motor to the lathe and hopefully fire the monster up, fingers crossed.

Nice job, you are well on your way.

This is for lacing tractor belt, but pattern is the same:

How to Lace a Flat Belt (http://www.farmcollector.com/Looking-Back/How-To-Lace-A-Flat-Belt.aspx)

Some folks use fish line, picture hanging wire, raw hide boot lace.

The belt can also be skived (tapered) and glued.

There are purpose made clips and a pin if you don't mind the click, click, click.

More:

Don't delay... do the Serpentine Belt Fix today! (http://www.practicalmachinist.com/vb/south-bend-lathes/dont-delay-do-serpentine-belt-fix-today-157227/)

South Bend book "How To Run A Lathe" has the lacing pattern in it. It can be bought or downloaded.

I am partial to the serpentine belt, skived and glued with CA made for plastics. Free take offs from your mechanic or bought in the right size for your set up. They do not slip and transmit a lot of HP.

fozz
25th May 2012, 06:34 PM
Thanks for the info Paul, very informative, after getting the beast fired up today the flat belt caused far too much vibration.

I'll try glueing the belt together and if that doesnt work then i'll see about one of those belts you mentioned.

The head stock box also needs to be stiffen alot more and theres a few other tweaks I'm thinking of doing to dampen the vibration if the different belt doesnt work.

I've also attached a short clip of the lathe in action.

Ross.

fozz
1st June 2012, 10:23 AM
Folks, have a question for anyone who cares to put their thoughts forward.

At the moment the jack shaft and motor are fixed to boards hinged to the headstock body. The problem is this is causing far to much vibration making the lathe unusable.

I was wondering what your thoughts would be on fixing the motor and jackshaft then using tensioners on both belts.

Looking forward to your ideas,

Ross.

fozz
10th June 2012, 02:58 PM
Big update!!!!!!!!!!!!!!!!!!!!!!

After my last post I got a PM from asking if I'd like him to come over and see if the problems could be worked out.

He came over last Sunday and positioned the jackshaft and motor in different positions and with some temporary bracing a great improvement was achieved.

left after explaining where to put the bracing and i've spent the week pulling everything apart and glueing and screwing it all back together.

I've routed a piece of "T" channel into the bottom part of the tailstock bed and with a bolt and nut the bed can be moved then locked in place.

Over the next few weeks it will all be filled and sanded then have a coat of paint and it'll be finished.

I put a piece of timber in the lathe yesterday morning that was off centre and while the head stock stayed as solid as a rock the tail stock bed whipped itself into a frenzy so with more 25mm thick ply applied at either end to brace it and more bracing under the torsion box the whole thing is rock solid and most importantly, usable.

A big thankyou to and those of you who gave advice and to Jim who put me onto the lathe in the first place.

I now have a lathe that will turn just over 1200mm long and bowls just on 500mm in diameter

Thanks for looking,

Ross.

RETIRED
10th June 2012, 06:45 PM
Is much better. Looking good.:D

fozz
7th September 2012, 12:19 AM
Gday Folks,

Thought I'd post some updates on the lathe.

The sliding bed sat on a built up platform but I found there was a certain amount of play in that set up so that's been changed to two 150kg rated full extension draw slides and is now so solid the whole lathe rocks when I grab the tail stock and try to move it side to side. Blocks of ply were added on both sides of the slide and the main body to attach the drawer slides. Picture one, two and three of this update shows this improvement.

The jack shaft assembly has also been modified. The original set up, while a great improvement, was let down by the hinges that eventually had too much play in them and allowed/created further vibration. I found some very heavy duty hinges from a gate assembly from my old ute tray back, welded a cross bar between them and botled the jack shaft to the hinges, solid as a rock now. Picture 4 shows that.

Also installed a handwheel and a perspex and ply guard to cover the head stock, got sick of being sprayed by grease from bearings.

Now, I do have a question. I started a thread a couple of days about camlocks thinking that may be the way to lock the sliding bed in place. While the links Fred posted were great I realise now that a simpler way could be better. I have been using a G clamp on the blocks either side of the drawer slides until now but am looking for something more permenant.

Any ideas will be greatly appreciated.

Ross.

steamingbill
13th January 2013, 08:52 PM
Hello,

Am very interested in your wooden pulleys.

In my web searches I have seen 3 ways of making them.

1. On a lathe

2. Using a table saw

3. Using a router

As I am making a lathe option 1 is not viable. Or rather it will be a genuine "bootstrap" operation with the first job of the new lathe being to make some more pulleys for itself.

How did you make your pulleys, is there a 4th method ?

Bill

fozz
14th January 2013, 12:31 AM
Hi Bill,

I turned them on another lathe :)