Member postings for mrbuilder

Thought it might be helpful to close this out

Paul is correct, according to Bison this is their reason.

As is this, for why they have the same feature on their vee holders.

That tongue and cheek is hilarious! I remember there used to be some words under Myford's listings about being upset about some guys on eBay breaking lathes out for parts.

Anyway, thanks for the help guys managed to pick up a very nice one.

Sorry everyone, was away from my computer until now... Yes being the owner of the original photo, I can confirm that it has a radius on the inside (as Neil has blown up). So mine look like the version Michael Briggs posted but his have a nicer finish on the faces.

Funny how sometimes you're talking about the same thing from a different perspective! Sorry it's blown out of proportion.

Yes Hopper just the chamfer, so I'm guess whatever tool they use to clean up the edge created that.

For me my question still stands on why it is there to begin with (i.e. the undercut with a smooth radius) particularly on the vee holders, I've contact Bison to find out. I have some genuine Dickson's coming and from what I can see from the photos they don't have this 'feature' at all.

While this makes sense for standard holders, why would it be on their vee holders? Apart from maybe a production process that Hopper mentioned. Or if perhaps if guys use vee holders occasional to hold square tools as well (which I have seen occasionally)...

As I said in an above post the one in the picture is a Bison T00. I have the receipt, the box it came in and a picture of the part number on the front - perhaps I was really fooled! Another member above said they have Bison tool holders that are like this. Yours may be a different size, from a different era... Designs can change over time.

Edited By mrbuilder on 17/11/2016 20:58:14

Posted by Paul Lousick on 17/11/2016 04:21:25:

Probably an undercut to remove any radius corner made by the cutter and to allow the lathe tool to seat against the bottom and side faces.

Paul.

Thanks. Those were my initial thoughts! To create a 90 degree seat against the two faces but then was wondering why it would be included on the vee holders. Perhaps they just use the same process as part of a chain even though it’s not needed on the vee holder.

Posted by Alan Johnson 7 on 17/11/2016 04:22:31:

It makes a neat fracture line - as one of my colleagues found out when machining cast iron with a substantial cut on a Hercus 9 inch lathe!

I was worried about that two, it must technically create a weak point than one without.

Does anyone know what this machined ‘groove’ in some of the quick change holders is for / why it is there? Have seen some with and some without.

Thanks guys. Good suggestions. I'm not in a hurry so I'll give it a bit more time.

I don't think that is correct based on what I have read. The ML7R had the 'standard ML7' saddle, cross slide and top slide.

http://modelengineeringwebsite.com/Myford_era.html

http://www.lathes.co.uk/myford/page19.html

Some of the locations where I was reading about the long bed ML7 actually and the use of Super 7 parts.

I guess in the end I'll never know for certain whether the parts with my lathe were original without the order form / invoice!

Edited By mrbuilder on 30/10/2016 12:04:11

I'm more specifically after the parts of the Super 7 that were supposedly used on the ML7 long bed rather than the differences between the standard ML7 and Super 7. From what I've read it might have been standard practice to use some of the Super 7 parts, however, mine hasn't got these 'features'.

Edited By mrbuilder on 29/10/2016 12:15:04

Thanks for the links. I might contact them directly or investigate a modern (possibly better) equivalent.

In regard to that, for example I've seen 10A, 240V, 0.75hp rated switches. So I was under the impression that there is a bit more to it than just that calculation - I think I remember something along the lines that the "hp rating" is the amount of current the switch can handle at the time the motor (or other device) is turned on.

However, I'm certainly not an expert, I'm constantly trying to get it clear in my mind how _everything_ I use/come in contact with works and to increase my understanding!

While the digression is interesting Does anyone know the answer to my question? My understanding is the HP rating of the switch doesn't matter if it is not being used to control the motor i.e. on/off but what max. amperage is the Dewhurst rated for? Interesting that it is not in the manual but understandably it's "old school".

Edited By mrbuilder on 21/10/2016 09:13:05