Member postings for Chris V

I have a GHT pillar drill, the base has a tee nut fitting specifically to fit to my Myford M Type cross slide, ie it does not have the usual base casting. Whilst it is not in use I wish to have it stood upright so thought I'd make a base that the tee nut can fix into. I see Noggin End do Meehanite by the inch by 120mm or 150mm dia which would suit my needs, I think.

My plan would be to use my Amolco to cut the tee slot part way through, stop and back out, having roughed out the centre part with a straight cutter. The tee slot is 3/4" at its widest.

Ive never cut a tee slot, or yet milled cast iron or Meehanite for that matter.

My question is if I got the slot cut with the tee cutter, should I stop the mill and back the cutter out the slot, or keep it running and back out, running the risk of climb milling?

I'd really rather not mess either the metal or cutter up first time I try!

Chris.

Thanks very much John, yes that clarifies a lot.

Plenty for me to think on now! (-:

Cheers

Chris.

Thanks very much John, that's great info, yes a photo would be really good to see too!

Chris.

Well as expected some great advice thank you all.

Not done it yet, good point, I am indeed mixing metric & imperial so one button on either side will do me for now.

John Baron, what sort of register did you use for your sub base, a couple of pins screwed into the base?
Or milled slot with a length of bar set (screwed)into it?
Also why such a thick base, perhaps you have a big heavy duty mill?

Howard, thanks yes a couple of fixed stops will be made also for belt & braces.

I hadn't considered the heels of the clamp down buttons marking the table, apart from removing the sharpness
off the corners how do you suggest avoiding this?

Chris.

Thank you all so much for the prompt replies Dave & Emgee!

Yes I am aware about the risks of breaking out the table, but it dosen't hurt to be told again! (-:

Journeyman yes those are what I shall be making, I found a drawing online elsewhere but you give a much more detailed guide to making so I shall fine that useful. Looks to be a very interesting website too, don't think I had found that before so thanks again!

Chris.

I have a 3" milling vice to use with my Amolco Mill. The vice is the type with holes along each side so I'm going to make some hold down buttons to locate in one hole each side that are then screwed down into tee nuts.

Should I be making just two, one for either side? Maybe one spare, or did I read somewhere you should have 3 points of contact which would suggest I need 3?

Cheers

Chris.

Hi Noel, thanks very much for this, good to know as I want to keep safe!

Cheers

Chris.

So I keep the gas cylinder outside, out of the sun, throughout the year?

Thanks very much Jason.

On that ive just ordered the more modestly priced kit and can afford a box of matches with what Ive 'saved' (-:

Cheers

Chris.

I sat down this morning to order both gas and a Sievert General purpose gas torch kit as kindly recommended by Jason and Terry on other threads.This will be my first proper torch outfit.

Ive paused as I really wanted to avoid having to manually light it, rather to have pizzo ignition and have been looking at the Promatic Auto torch kit instead.

This comes with a smaller burner than the General purpose kit (from Hamilton Gas), 19mm rather than 28mm, but they do larger sizes, 25mm being the nearest.

I have a fairly small and confined workspace so the trigger control really appeals for safety reasons, the workshop walls are lined in nice dry fibre board!

So apart from the extra expense, the Promatic offers the trigger on off and what is described as a load relieving trigger system, which I assume is a button to push in to keep the torch trigger on if I so wish.

Does anybody use one of these and am I correct about the load relief?

Are there any downsides?

Thanks in advance

Chris.

David did you spin the boiler end caps yourself? It all looks very neat & impressive!

Chris.

David George, just sent you a PM.

Chris.

Feedback! (-: Success!

Once the supplier re sent the correct size pulley that I'd ordered ie 2.5" I bored it out this morning and fitted the new belt. Checked the top spindle speed and its 860 RPM, quite noticeably faster, so job done.

Many thanks to all that helped me with this!

Chris.

Thank you Howard!

Chris.

Ah thank you David, that's good to know for reference!

Chris.

Thank you so much Simon for explaining this so I can understand.(not always easy with me!)

Well the good news already is I have located a 2.5" dia pulley so that should be near enough!

Thanks again!

Chris.

Thanks so much Simon!

I thought in a broad sense I had cracked why the higher speed was stated, in that the CS pulley was originally a 2 step, of what diameter I do not know, only that mine is a single and being of the right period/look and cast iron I am keen to keep it. If the original two step pulley's larger diameter was smaller than mine presumably the lathe would run faster?

I also presume the motor would have had to have had a 2 step pulley??

Lastly if the 2.25" option is going to only get me part way to my top desired speed, an I correct in my understanding a 2.5" pulley = 857 RPM?

(I'm thinking I might wait a bit to see if I can find one nearer the right size to achieve my desired speed increase.)

PS the 3 step pulleys on both the lathe and counter shaft are 2.25", 3.25" & 4.5" dia.

Ok great thank you all for trying to help me.

First off Simon, yes my mistake my top desired speed is 874 RPM not 840 RPM.

Yes its all flat belts.

I just went out and checked and the motor is indeed running at 1425 RPM as near as I can see using my vintage Smiths RPM counter.

Whats missing? Well my large countershaft pulley although period is not the original and is one step only.

So looks like I'm achieving one step down from top speed as stated on Lathes.co.uk. That's stating 12 speeds utilising back gear as well, I have 6 speeds which is fine for now.

Oh the countershaft speed I just checked is 285 RPM.

Hope that clarifies!

The top speed of my Myford M type is meant to be 840 RPM. I tested it today and found it is 600 RPM.

The motor plate states 1425 RPM.

I do not wish to change the large countershaft pulley which is 8.25" dia.

So I'm thinking I can increase the motor pulley which is currently 1.75" dia.

Having looked on line at cast iron pulleys (I don't want Ali) I currently have two pulley options for the motor. One is 2.25" dia, the other 3.25" dia.

As my arithmetic abilities are less than great, could someone please advise which is likely to be my better option to increase the top speed by around 240RPM?

Chris.