Myford Rear Tool Post "Block"

So I can use my spare Dickson tool post at the rear, anyone know where I might be able to purchase one of these blocks (circled in blue)? (Short of making one)...

Photo credit: Swarf, Mostly!

Hi

Your photo shows the Myford rear toolpost - it has has a special QC tool holder and parting blade. The whole shebang is available HERE .

I have one and it works well - one for your Xmas list maybe?

Norman

Norman, the OP says that he already has the top bit! Your recommendation would leave him with two!

Mr. Builder, I bought a lump of cast iron from College Engineering but dreaded the job of hewing away a fair proportion of it. (College Engineering wisely counsel prospective customers to allow for dimensional tolerances on the material; I did that but on the lump I received they were all + !) I don't have a mill so would have had to do the job on the Myford. While I was working up the courage to start the job an 'orphan' ML7 block appeared on eBay and my bid was successful. I should explain that I was starting with the QC rear tool-post model sized for the 254S, also an eBay purchase. I could have reduced the height of the lower block that came with that but I chose not to go down that path.

I note that some tool-posts have a hole in one corner - mine doesn't. The lower block has its two lugs to fit in the cross-slide tee-slot to prevent the block from turning. I have found that my top part does suffer a tendency to rotate. A hole in the lower block and a suitable pin would prevent that.

I still have the lump of cast iron!

Best regards,

Swarf, Mostly!

Edited By Swarf, Mostly! on 21/06/2017 11:22:03

Edited By Swarf, Mostly! on 21/06/2017 11:22:30

Assuming mrbuilder is primarily interested in parting off he will need the inverted parting blade holder and a parting blade as well as the material to make the block out of. By the time he has bought those along with a suitable chunk of material there probably isn't much, if any, saving in DIY if he sells the Myford size QC post to help defray the expense of to buying the complete kit. The link from NJH quotes a little over £100.

Carving out that large lump with ordinary ME shop gear isn't going to be fast or fun. I have the gear to do it faster and easier but still wouldn't consider it a sensible way to save £10 or £20.

Re the toolpost rotation problem encountered by Swarf Mostly proper Dickson posts have a suitable hole and anti rotation pin as standard. If you don't have, or don't wish to use, the anti rotation pin a thin card or aluminium washer betwixt post and support block considerably improves grip. Smooth steel on smooth steel or cast iron doesn't have much friction. General rule is that the centre third or so of such mating surfaces should be relieved to ensure that contact is made towards the outer edges where there is plenty of leverage against rotation. I would assume that the toolpost is so relieved but best to check.

Clive.

Just so Clive!

I was in the same position and yes I ended up with a spare - I still have it and maybe it will be useful some day. The important thing about QCTP is to have plenty of tool holders - otherwise the QC bit is not that at all!

Norman

Make a block for it, it's a fairly simple job and having a matching rear QCTP is lovely

- Nick

I thought making piles of swarf was the fun part of the hobby

You could make it a bit simpler by having less of a step where the two studs go or even use cap head screws into drilled and Counterbored holes which would save having to remove as much metal there. Lugs could be replaced with a bit of bar set into a milled slot. So that would mean it is really just a rectangular block, quick enough to tidy that up in the 4 jaw then poke a few holes in it.

You could make the base block from two pieces of mild steel either welded or bolted and dowelled together. Or you could buy a casting for a Duplex or GH Thomas style rear tool post, available from Hemingway Kits or occasionally on Fleabay.

In MEW Roger Vane described and gave excellent instructions for making the base which looks almost "Myford".

As I have three QCTP's and use only one at the moment I decided that this was to be my next project. So I bought a block of Meehanite and put it on the shelf.

I then decided to change my mill, and whilst waiting for the new machine I covered all my workshop shelves (19 of them!) with 3mm perspex - easy to wipe clean.

Whilst waiting for the new mill I decided to use the present Warco WS16. An excellent machine which has given excellent service and much pleasure over the last three years.

In the meantime the Meehanite had disappeared!!!!

I have turned out the w/s but no cast iron.

So looked in the drawers and found a block of ali that would be just right.

Into the mill and after watching the table weaving it's way there and back a few times I had the block.

Mounted on the S7B's x-slide it is as near perfect as anything - even allowing for me having made it.

So don't buy one - make it.

If I can (I'm 85, a carer and church organist) anyone can.

Good luck

Richard2.

Spend £30.00 on the 'bay and save a lot of messing. http://www.ebay.co.uk/itm/REAR-PARTING-OF-TOOL-POST-MYFORD-LATHE-COMPATIBLE-/352089228819?hash=item51fa274613:g:syUAAOSwYvFZOFak

Whichever route you take to getting a rear mounted part off tool it will be worth it. I made a simple block for my 14"x40" lathe and used an indexable tip holder from ARC. The set up lives permanently on the back of the cross slide and does not interfere with day to day turning ops so no need for quick change.

This.

I'm convinced that the permanent fitting is a major reason for the success of rear mounted parting off tools. As its always there in the same place not only is it worth taking time and trouble to get it set just so but you also get used to the feel of the beast so as to get the best out of the system.

Being an inevitably rather heavy cut, especially on small lathes, with restricted chip evacuation parting off is notoriously sensitive to small errors in setting or technique. Its hard to get it exactly right each time when changing tools in the normal front mount position. Although small variations from optimal setting can be compensated by suitable adjustments to technique such faffing around makes life harder. Especially for teh less experienced.

Clive

+1 on Clive Foster's observations.

After a long run of rear-mounted parting successes, I recently broke an insert half-way through a parting cut. Checking the tool height with a new insert showed the tip to be slightly low, not on centre as originally set up. I'd shimmed the tool holder with a strip of drink-can aluminium. I think the aluminium deformed under pressure, slowly dropping the edge until it dug in.

Turning and facing are much more tolerant of errors in tool height.

Dave

I made mine for my S7 out of a MS block i leave it on most of the time

Like Nobby my rear mounted tool post is just a mild steel block. I made a new cross slide for my lathe and incorporated tee slots which I did not have previously so no problems getting the parting tool square.

Clive Foster:

"I'm convinced that the permanent fitting is a major reason for the success of rear mounted parting off tools."

That's a very interesting and persuasive argument in the debate about rear-mounted parting tools and one which I have not previously seen mentioned.

My first of these was the GHT design which, following Duplex, has an indexing and rotating two-tool turret. The merit of this is that the tool can be tailored to the job. This approach also allows the use of other tooling such as boring and knurling tools at the rear but requires a two-piece design - block plus turret - which may lose some rigidity.

I've made two other toolposts for the larger lathe, the current version being equipped with an ISCAR tangential tool:

I may mill a slot in the other side of the turret for another tool. Turret is non-indexing at the moment and when I need to set the tool I refer it to a straight edge against the chuck, etc.

Thanks for all of the replies guys, appreciate it.

Undecided whether I'll make one seeing as isn't available separately, just another project to add to the 1001 others!

This thread reinforces the fact I "need" one though