Starting to build fast speed gear for Drummaond Lathe Rebuild

I have started buying parts for my high speed lathe rpm for my Drumond.

Since installing this i have had issues with a RUBBISH 3PH INVERTER AND RUBBISH MOTOR AND HAD NO REFUND FROM THE SUPPLIER FOR THE MOTOR WHICH HAS BEEN DESTROYED BEWARE WHO YOU PURCHASE THIS FROM.

I have sicne settled on a single phase motor which runs too fast for high speed and have started buying parts to make this . I have purchased two additional pulleys a 4" and a 5" and some new bearings

I cannot seem to find a bearing guide so am going to make my own out of angle iron and tool steel.

Hopefully some more bits will arrive soon. This will be much nicer that the lay shaft as will live under the lathe

Apart from the poor service from the supplier, what brand of VFD and motor were they? Sounds very frustrating so best avoided from what you say.

Hi Martin, I wouldn't go to the expense of tool steel, bright mild steel square should be perfectly OK or even square hollow section (Box) on this type of bearing and it can be stich welded to your angle iron or even tapped and screwed. Put one in each channel on the bearing housing, so that they slide easy without undue slop. There should be no contact between the outer edges of the channels of the housing and the frame.

Regards Nick.

Thanks Muszzer , Nicholas

Yes very frustrating but wont make same mistake again buying inverter technology . The rails are looking harder to make than i thought through lack of materials i need a larger section than 25 x 15 . This is why I thought of tool steel I am presuming 25 x 25mm. I was going to use angle to make the box up and bolt rails to it with a long piece of threaded bar to pull it down it wont need much force as the weight of the motor is on a counter balance pulling on lower belt too. do you think its worth making it without threaded bar in first case. How do you manufacture a fast thread is it just a coarse one?

Cheers Martin.

Hi Martin, not understanding your ideas, but have a look at this **LINK** which is the general type of set up for these bearings, which are nearly always bespoke.

Regards Nick.

I'm hoping that when you mention 'tool steel' you mean what we call mild steel as in ready to be machined drilled etc. Tool steel will be impossible to drill or cut as it is the stuff that has to be ground into..... tools.

If you are needing sections of 25mm square then you probably should use tube. Solid is going to be heavy and expensive.

I make parts in 01 Tool Steel and D2 Tool Steel, I buy both in fairly free machining annealed states, they turn and mill very nicely. Once I've heat treated them they don't machine so well

- Nick

Ah yes , I'm being an old fashioned model engineer only using tools steel to refer to HSS. The varieties available to MEs is now rather wider than the ground flat Kennions stocked.

It's just not that simple -

http://www.buffaloprecision.com/data_sheets/dsm2hs.htm

- Nick

More parts arrived . Thanks Nick for the datasheet

Managed to get my 3/4" shaft made so it was .747" to take bearings and pulleys today. Its starting to take shape I am still shoppig for 1m of 15mm x15mm for tracks to run this on

Sorry the technical drawings were not good the runners need to be 15mm square so not quite so heavy as will be quite short but will try to get 1m

Hi Nick am going to make a box out of angle to put my rail in similar to this one but with differant ends as mine needs to hang from under the lathe surface on a bracket i made up.

I am unsure if I wil need to construct lower threaded piece as gravity and the weight of my motor will pull this downward. but will make boxes up with this in mind. It might be that the pull wil be so much that the screws will have to go on it to keep it balanced

Edited By Martin Newbold on 09/01/2017 17:46:24

First try at rough placement

Got a bit further

Well i drilled bars and re-ground one which was sticking

Well I had to buy new angle as the B&Q angle iron lol now mild steel was not regular or a right angle inside and out. This mean all the work i had done was rubbish. I have purchased proper angle from a wholesale stock dealer and have got back to were i was . I have decided to use 3/4 gate eyes for the winding mechanism and have some on order . I still have to drill top plate for old mounting bearing holes and have a dry run with it cramped up before both are welded.

I made the securing pieces to bolt under top and roughly cramped together to see if it all slides .

B&Q angle iron is perfectly good as angle iron. Rolled angle iron isn't a precision product, up to 100mm leg length it can be up to 1mm out of square either way.