Member postings for Avon

Thanks Clive,

I'll take it out this weekend and see what I can find.

I don't actually know when it last ran properly as I stripped and rebuilt it without having tried to run it (probably should have done). I have stripped and cleaned the motor and both windings have insulation readings in excess of 10M.

Regardless of what I discover I will pursue Mike's suggestion of fitting a new unit - it had crossed my mind to do so anyway.

I'll update the thread with findings!!

Peter

Thanks Dave, I'll do that, that said it's been single phase as long as I remember and I've merely replaced the old wiring.

Ill have a go over the weekend.

Hi Steve,

I'll investigate that idea. Do you know of any that could have remote make and break contacts. I ask because I'm keen to retain the front panel which has the Start button in the centre of the panel and the stop at top right. I doubt anything current will be laid out exactly the same and so a couple of small microswitchs could be used to trigger the MCB.

Regards

Peter

Hi,

The attached photos show the contactor fitted to my Centec 2A. Although the contacts close and the motor runs well almost any load will cause it to trip. I've checked the motor windings and they have good insulation and the whole machine runs smoothly.

The label on the contact suggests they're adjustable, but I can see where or what I would adjust - any ideas gratefully received.

One thought I had was that the trip is activated by overcurrent affecting a bimetallic strip and I wonder whether its due to the insulation material around the thermal strip having perished and dropped away over the years. If so can anyone suggest what to replace it with?

Grateful for any ideas.

Regards

Peter

Dear All,

Many many thanks for your many and varied responses. In summary:

1.Think about using a plug guage rather than calipers,

2, Small cuts, and

3. Make d..n sure that tool is sharp.

I think this is a thread I may refer too again in the future.

Thank you all for your comments.

Peter

I have been trying to bore a 0.6" hole in an aluminium pulley using my S&B Model M Mk 1. To my mind this is a very simple task in a machine that shouldn't have any issues whatsoever. This was my technique:

1. Drill the centre using firstly 1/4" then 1/2" HSS drills held in the tail stock.

2. Progressively bore the hole until it was 0.590" using a home made cutter held in a holder that my father had made: looks to be maked from hex bar turned and drilled to mount a cutter ground from 3/16 rod.

3. Final cut of 0.005" to remove the last 0.01" from the diameter of the hole. End result a hole that is 0.604" - usable, but 0.004" greater than intended.

Possible causes:

a. I didn't look carefully when applying the cut and added 0.007" - I'm pretty sure I didnt.

b. The cutter bar 'sprang', but I was careful to make the final cut a light one to avoid that and had made several passes of the previous cut to make sure it was 'on size'.

c. When I thought the hole was 0.590 it was actually 0.594". This is possible as I'm using a digital caliper to measure the inside diameter and I do get different readings on occasion, but I was careful to check for consistent readings before deciding how much to remove.

d. Did I grind the tool incorrectly? I attempted to have a slight rake and with a rounded cutting edge - I certainly wouldn't claim to have set it to any particular angle and there was some slight buildup of aluminium on the cutter, but if anything I would have expected that to reduce the depth of cut not increase it.

I'm keen to be able to turn accurately and would like to know where others think I might have gone wrong.

Grateful for your thoughts.

Thanks guys, glad to see there's no absolute answer. It's definitely 3/16 so not sure.

Any suggestions for good suppliers?

i have what looks like a Stuart 5 or 7? Vertical with reversing gear. It doesn't have an 'S' on the valve cover. I'm trying to identify the air/steam connector thread size. The internal diameter is 3/16". What thread do you think it might be and where is the best place to buy fittings?

Many thanks.

Hi Duncan,

I counted 28 on the driving shaft and 32 on the driven. By my calcs that gives approx 15% reduction in speed of 1600 input shaft and 1400 at the quill. Photos below:

Hope that helps.

Edited By Avon on 27/07/2020 22:38:24

Hi David,

Address received - will post next week.

Yes I do have the handbook - not really sure where I got it actually, its in PDF - did you send it a while ago?? (i'm getting increasingly forgetful!!).

I found a centec router on ebay, which looks like it might fit - and I think I have some of the other items that are with it - I'll have to have another look in Dad's workshop as it may still be there since I wouldn't have known what I was looking for!

All the best.

Peter

Hi David,

Can you message me with your address and I'll get it sent back - absolutely not a problem, I'd rather it was in a good home and I know what you mean about searching for things you no longer have!!

Hi Dave Halford - I've never been aware of a slotting machine, though the name obviously gives away the intent. I guess its an adaptor intent on languishing in a box until its use is obvious!!

Hi 'not done it yet' - looking at the half nut supplied by David I suspect that my father was trying to make a halfnut and then decided that a full nut was easier, I can even see where he filled in the slot.

Regards

Hi David,

Amazing response - really appreciated as parcel arrived this morning. But sadly it’s the smaller size as mentioned elsewhere. I can either return it or hold it in case someone else has a need.

I guess we should have checked. Such is life.

Let me know what you’d like me to do.

All the best.

Peter

Hi Duncan,

Email sent with both DXF and DWG. For info the link to the ONSHAPE drawing is:

https://cad.onshape.com/documents/a2e0a0ebaf385baddcff3f15/w/d4fa5ebbd6215d9ab93d4805/e/cf7ccd99fd7d2bb21ba9292c

I use 1/128" as that's what my calipers give me - I'm measuring as built/worn out so its almost never a nice number, though on occasion I have thought that my lathe in particular is more metric than imperial!

For info, do you have any idea what dirty green accessory might really be for in my picture above? Its a perfect fit to replace the Quill Head on the Mk3 vertical unit, but I found nothing in my fathers workshop to fit it - my suspicion is it should be a grinder attachment, but thats a guess.

Any ideas?

All the best.

Hi Duncan,

Hope these help. If you want more from the drawing I can share using Onshape (my goto CAD package)..

Regards

Hi Duncan,

I removed the table before I even discovered the nut - its about 30years since I've seen this mill working so have been stripping it blind!. I'll do a drawing and photo of mine and post here - it might be more helpful.

Shouldn't take too long.

Regards

Dave, not done it yet,

At this stage I've not even started to think precisely what I'll use it for, and certainly won't be commercial. But since I'm spending the time refurbishing it I thought I'd like to restore it to as near original as I can.

I suspect that like Dave, I'll not be bother to do it too often, unless I can use the quick feed to actually make a cut on each pass. It did occur to me that since I have an adaptor (see photo) for the Mk3 Vertical Head that looks like it should hold a grinder perhaps I would use the quick feed in that circumstance.

Regards

Mine is the underdrive version and just checked that the leadscrew (is that the right term for a Milling Machine?) is 5/8".

Mine has a full nut which obviously can't be disengaged - I assume my father fitted it, but really not sure. Neither am I sure whether I need to fit a Half Nut - it seems correct to do so as that was how it was designed, but a number of posts suggest the quick traverse facility isn't really needed?

Hi DAG, I know this thread is quite old, but wonder whether that half but is still available (for a reasonable consideration 😊 I have a 2A which has a solid nut fitted and I’d like to get it back to the original state?

All the best.

Peter

Excellent, many thanks for the prompt replies - now off to source some material and learn how to sharpen my tools properly!!

I had used the talistock to support the die, so reasonably confident the error was in not being so careful when tapping the original piston.

I'm learning!!

well that wasn't a success. Lesson to self: 'be more careful when tapping a hole to make sure that the tap is square to the job'! I have a beautifully fitted piston rod with a piston that now wobbles!

So it looks like I shall be taking Redsetter's advice and making a new piston. Therefore, a question: What material should I make it out of? The original is clearly steel, but I don't know what grade - does it matter?: