Author Topic: Lathe mounted slotting attachment  (Read 20188 times)

RobWilson

  • Guest
Re: Lathe mounted slotting attachment
« Reply #25 on: December 15, 2016, 03:46:09 PM »
 :clap: :clap: :clap: Nicely done Pete  :thumbup: 


Looks like your making good progress  :dremel:


Rob

Offline PekkaNF

  • Hero Member
  • *****
  • Posts: 2523
  • Country: fi
Re: Lathe mounted slotting attachment
« Reply #26 on: December 16, 2016, 05:33:20 AM »
Very nice work. Looks like it is going to one solid tool.

.... Just got a slight undercut where the weld started/finish on the 1" x 1/2".  :scratch: Any ideas how to avoid that?

Pete

I have experienced same thing with hand held tools. When sanding into step/stop just can't controll it well enough. Sometimes it helps a little to grind from the other side....sanding drum will try to lift a little instead of digging in. I'd just leave it as it is. It shows that it has been hand finished lovingly and not mass produced. It looks good. And anyone done the same thing appreciates it - fools don't see nor understand the difference.

Pekka


Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #27 on: December 17, 2016, 12:22:52 PM »
Thanks for the comments.
Just waiting for a new piece of cast iron to arrive. After a re-design of the re-design  :scratch:, I have decided that the best way of ensuring that there can be no possibility of sideways movement of the ram is the have a lip on three sides of the body, so that in effect it hooks-over the top-slide. It does mean though, that the hole for the securing stud will have to be very accurately placed and drilled... :scratch:
Pete

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #28 on: December 22, 2016, 02:13:37 PM »
A little progress after the new chunk of cast iron arrived. Pic 1 Nominally it is 130 x 60, but is slightly hollow on the width.

Pic2 shows the recess being rough cut with a 20mm Little Hogger, after marking out.

I deliberated for quite a while as to whether to drill the stud hole first or last, and decided to drill it first.
 
The stud was locked into the top-slide by a hex-keyed screw from underneath, so was easy to remove.

Pic3. The recess was finished to size with a 6mm carbide 2 flute, usually used on my router, and it worked well. Also used to finish the whole depth to size.
 
The part-finished chunk fits the top slide like a glove. I would like to say that the stud just dropped in...but cannot. :(
After using a 1/2" drill to enlarge the 12mm hole..it now fits, as pic4.

Pete

Offline krv3000

  • Hero Member
  • *****
  • Posts: 2183
  • Country: gb
Re: Lathe mounted slotting attachment
« Reply #29 on: December 22, 2016, 05:29:04 PM »
its coming a long

Offline Manxmodder

  • Hero Member
  • *****
  • Posts: 739
  • Country: gb
Re: Lathe mounted slotting attachment
« Reply #30 on: December 24, 2016, 06:48:57 AM »
I have a lever operated capstan attachment which came as part of the accessories for my L6 Harrison.

I have,on a couple of occasions, considered fitting an indexable boring head to one of the turret sockets and using it as a lathe bed slotter. It would involve disabling the automatic rotary indexer mechanism,but I think the idea has merit......OZ.

Helixes aren't always downward spirals,sometimes they're screwed up

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #31 on: December 24, 2016, 08:09:39 AM »
its coming a long
Albeit...slowly  :thumbup:
I have a lever operated capstan attachment which came as part of the accessories for my L6 Harrison.

I have,on a couple of occasions, considered fitting an indexable boring head to one of the turret sockets and using it as a lathe bed slotter. It would involve disabling the automatic rotary indexer mechanism,but I think the idea has merit......OZ.

That mechanism looks as it would make a very nice slotting unit. I have never seen anything like that for my Harrison M250.
Pete


Offline Manxmodder

  • Hero Member
  • *****
  • Posts: 739
  • Country: gb
Re: Lathe mounted slotting attachment
« Reply #32 on: December 24, 2016, 08:30:32 AM »
The design for the M300 is more traditional with the capstan wheel to operate it and the turret set at an angle.

Here's a photo of one for an M300....OZ.


« Last Edit: December 24, 2016, 05:38:00 PM by Manxmodder »
Helixes aren't always downward spirals,sometimes they're screwed up

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #33 on: January 16, 2017, 04:42:06 PM »
A little more progress today. Project was stalled for the lack of a 21.50mm drill. Ordered one which came after Christmas.
Then I saw a cheaper one 27/32" on EB so bought that too. When I mounted the 21.50mm drill today, the parallel section at the end of the flutes was eccentric by what looked like a millimetre, so not much good.
Fortunate that I had the other one, which worked perfectly,(in the same 5MT-3MT and 3MT-2MT adapters)
As I had to use the lathe for other jobs, I had removed the body from the top-slide.
Before doing so, I measured the carriage to cross slide distance and wrote it on the top. This gave me a good start to ensure a concentric hole with the existing 21.00mm bore.
Followed by the 22mm reamer  and trial fitting of the 22mm ram.
TBC
Pete

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #34 on: February 09, 2017, 10:59:46 AM »
The ram pivot caused me a few problems, experimenting with either machining the 10mm hole, slot, or thread first. eventually ended up with a usable one. (1)
The collection of bits (2)
Ram assembly complete (3)
Pete

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #35 on: February 09, 2017, 11:06:32 AM »
At this stage it would have been good to say it worked fine, but when fitted to the lathe, the handwheel was in the way.  :scratch:
Alas, I had forgotten the extra thickness on the bottom of the ram pivot, so milled 3mm off, (pic 1) shows  temporary 10mm pin for checking clearance.
Now sorted (Pic 2)
Pete

PS Nearly forgot. Enormous thanks to Rob Wilson for his inspiration and assistance.  :thumbup:

RobWilson

  • Guest
Re: Lathe mounted slotting attachment
« Reply #36 on: February 10, 2017, 03:12:40 PM »
Very nicely machined Pete  :thumbup:


Looks like your well on the way to having this finished  :dremel:

Rob

Offline Biggles

  • Full Member
  • ***
  • Posts: 236
  • Country: gb
Re: Lathe mounted slotting attachment
« Reply #37 on: February 11, 2017, 05:44:55 AM »
Nice work pete, I see CES are advertising a casting but with no price!  :coffee:

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #38 on: February 11, 2017, 04:43:29 PM »
Rob & Biggles, thanks for comments.
Rob, you cannot rush these jobs.  :bugeye:
Biggles, not much improvement to replies #19, #20 and #21 then. :doh: Their casting would not be much use, (to me) without a large mounting plate underneath it.
Pete

Offline RichardShute

  • Jr. Member
  • **
  • Posts: 85
Re: Lathe mounted slotting attachment
« Reply #39 on: March 11, 2017, 01:51:11 PM »
No point in rushing indeed, mine started as a lever operated tailstock that looked like a quick conversion, but obviously wasn't.

I then made the fabricated body and got bogged down with other stuff for ummmm, about 6 years! Well, I needed to let the fabrication settle down and stress-relieve, didn't want it moving about once I'd flattened the base now would I?

It's made to fit in place of the compound slide on my S&B Sabel and with minor modification can fit on either of my other lathes. it'll obviously also fit a Boxford or SB9 as is. The link bearings are a bit small for preference, but with the work load it's likely to get I don't see it as an issue.


I finally only finished it last week because someone else wants to borrow it. It goes without saying that the job for which I had it ear marked turned out differently and it wasn't needed and I now have a slotting head for the mill in any case......

Ho hummm
Richard
For every fool-proof solution, there is a fool greater than the proof

Offline Spurry

  • Sr. Member
  • ****
  • Posts: 346
  • Country: england
  • Norfolk, UK
Re: Lathe mounted slotting attachment
« Reply #40 on: March 11, 2017, 02:10:41 PM »
Richard
That looks like a hefty old casting to start off with. Was the cast section much of a problem to weld?
Pete

Offline RichardShute

  • Jr. Member
  • **
  • Posts: 85
Re: Lathe mounted slotting attachment
« Reply #41 on: March 12, 2017, 03:44:01 PM »
Hi Pete,
sorry to have mis-led you, I didn't use the casting at all in the end, just the barrel and moving bits etc. The whole body is a fabrication, 2" steel round at the top, 5/8" 'something nasty' plate for the base and some 5mm black iron plates for the sides and end. What I had lying about in other words.

Cheers
Richard
For every fool-proof solution, there is a fool greater than the proof