Manky Monkey Motors

I finally got round to looking at this Drummond lathe.
I plan on fitting a countershaft to run at approx 300rpm, so i have been looking at the headstock speed and i`m confused!
I have an electric motor running at 1490 rpm, when i attach the belt directly onto any of the 3 pulley`s on the headstock, I get 3 very low speeds, 91, 115 and 156 rpm. I should be getting 3 extremly fast speeds of over 1000rpm.
Now, the only thing i can assume is that i am losing speed through the 2 back gears on the shaft behind the headstock.
Although this shaft disengages, without it engaged, the headstock does not turn, so i assume it has to stay engaged?
With the back gears disengaged, the pulleys turn and spin free on the headstock shaft, so is my problem at the right side of the pulley cone, should the bull gear be attached to the pulley cone?

I think i just answered my own question! i`m off to look at the bull gear  ;)

I have absolutely no idea what you're talking about.  ???

I don`t think i do either.......but it sounds good  ;D.

Yep, sorted it. The bolt on the bull gear wasn`t engaging the cone....it kept slipping past it. Slackened everything off, tapped the gear back along the shaft, re-tightened and hey presto! running at full speed.
Next job is to do a few calculations to sort out the pulley sizes, then make the countershaft.

TB dont engage the back gears they will slow it down, that's what they are there for.

Do you have a countershaft now?

Cheers mate  ;).

Not got a countershaft yet, I have sat and worked out various combinations of pulley sizes though.
I know the norm is to use a match for the headstock cone and reverse it, but i`m unlikely to pick up another cone the same, so.....
If i drive the countershaft with an 11" pulley, i get a tad over 300rpm (307.48 to be precise and anal!), using a 2,3,4 & 5 inch stepped pulley on the shaft will give me a range between 136rpm lowest speed and 645rpm top speed.
If i add a 6" pulley, i`ll get 775 rpm top speed
I dont think the old girl should exceed 800rpm and with the back gearing in place i should be able to come to an almost complete stop  ::)

TB you can get new pulleys from http://www.abcpolishing.co.uk/ including the stepped 3 speed and also bearing blocks.

Thanks for the link Doc. I`ve just finished welding together a stand to sit behind the lathe to mount a shaft onto, got a fella who says he has a Boxford shaft somewhere, mine for £15 if he finds it!
A bit of research shows the Boxford used a 6" pulley to drive the shaft so i need to redo my calculations, should be ok, just means the counter will be turning at twice the speed i`d originaly planned on.
Did you ever sort out a quick change toolpost? I have looked at the universal type but think i would need to grind down the height of the tools to around 5mm to keep them central to the workpiece, then i would still have to shim at the top to hold them in the holder.

Trikertim001 I'm not using a QCT on mine as I am going to keep it original (ish).

Well spotted!  ;D
Not that it was any help.

Haha not like here on MMM eh!

Very true!
If i overhang the tool holder, down the side of the top slide, do you think i`ll get excessive chatter? I`m not sure how tight the toolholders fit to the main block and all the ones seem to be above/on the top slide.
I presume that as these devices are height adjustable, it will not matter if the bottom of the tool holder is not rested on anything?
There is an `unknown` top slide on ebay at the moment, looks like it would fit ours, with a bit of shaving to the sides of the platform i think i could get a qcp on it  ;)

You presume right TB. The only way you going to find out if there is too much chatter is to try it.

I have a 4 way tool post I was going to fit but the main bolt on the topslide is way too big so I'm not going to bother.

I wish i could keep track of all the crap valuable items in my shed!
I pulled one of the villiers engines off the `need looking at` shelf and found it`s fitted with a 3 step pulley! so i had one all the time  ::).
Ah well, i`m waiting on the boxford one to arrive now so i guess i`ll be spoilt for choice  ;D

Don't take it off use the villiers engine to power the lathe, now that would be novel.

I had considered this, not with that engine, but one of the small ones.
It would mean rigging up a longer exhaust to exit through the back wall of the shed, but thats do-able.
There is also a countershaft shaft on ebay at the moment with a floating pulley, hmmm the more i think about it......

So, look what was waiting for me when i got home.

Kool! ;D

Where does the time go?!
4 months ago it was when i got that jackshaft, finaly got round to doing something with it.
Tis now mounted behind the lathe and working, sort of....the arm that i made to carry the adjusting bolt was fine to start with, after running the lathe through its various speeds, i find the arm bends forward when the belt is tightened.
The arm is welded onto an L shaped bracket that is bolted through the bench, i have 2 options open to me, firstly, turn the arm around so the leverage is acting against itself, or add a second L shaped bracket behind the arm.........

Photo's please TB.

Sure  ;D
The shaft and motor are mounted on a hinged wooden plinth.

This is the arm that holds the long adjuster bolt.
I have now turned it through 180 deg, so that it pulls the bracket back rather than together.
I still may have to `beef` it up but its better than it was.

All looks ok but you will need to strengthen everything and I would loose the wood and just use steel I have a similar set up but much stronger.

I also have my lathe mounted on a steel bench which helps alot I just weld bits straight to the table.

Strangely enough.....Thats what i sort of did this morning  ;D
The arm is now welded to the frame of the bench behind the lathe. I`m still running wooden motor/shaft mounts as i thought this may help with vibration issues. I have some 3mm plate so will give that a go.