I do have a couple of ccmw120404 I have not used if I can find a cheap milling holder on eBay. What designation would I look for?CBN would be prefered but carbide will do it.
Id do most of it with grinder and just use mill to get it flat and square.
BUT the boring bars I have don't fit the Dickson tool holders I have so I need to widen the slot.
I had thought of that but I have a few oversize boring bars.Or narrow the boring bars.
They are made of tough steel but it is not hardened and probably will cut a lot easier than a tool holder.
Have a look at the latest video from 'Cutting Edge Engineering'. He has an 80mm dia. boring bar that he holds in a four-way toolpost.
Make a holder up for bars. 32 or even bigger hole in it and use sleeves for smaller bars, even better if you can make your own holder up that fits direct onto the toolpost if it is a wedge or Dickson type post.I had thought of that but I have a few oversize boring bars.
I have thought about boring a 40mm hole into a bar and welding it to a 28mm rectangle of steel in the same was as a couple of the parting tool holders I have. But time is not on my side this week.......that said the snow and my dogs medication made me cancel my Fishing match tommorow so one I grab his meds I can crack on. (Once I fit the Gib back into the lathe saddle)
Make a holder up for bars. 32 or even bigger hole in it and use sleeves for smaller bars
The weak part is my lathe now hood. As it needed the gib strip adjusting (or replacing) or more worrying the lathe is too worn. But I think I am able to see if I can solve that today.Make a holder up for bars. 32 or even bigger hole in it and use sleeves for smaller bars, even better if you can make your own holder up that fits direct onto the toolpost if it is a wedge or Dickson type post.
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For interrupted cuts you mentioned earlier the bigger the bar the better for obvious reasons and a strong negative insert is best but other options are U-Drills or Komet style bars (see pic) they can both work well although the U-Drills really need a through hole due to the insert shape. Another option is often an end mill of as close to the right diameter can be used if you can hold it somehow, again making a tool block up can help with this.
View attachment 283215
Another idea is shown in a YT video by El Metal Raymond Menendez, called 'Alargador portaherramientas para torno'.
One thing to ponder on when 'overtooling' (or undertooling) any machine is the challenge of setting the cutting tip on centre. On a standard Dickson setup, you can quickly bottom out or top out the adjustment so it it worth checking this aspect before modifying a holder.
With a round boring bar, you can also run out of horizontal depth for the clamping screws, not a problem on square-shanked tools as they do not mind being clamped off centre, but the milled flats on a round bar only extend a set amount.
The weak part is my lathe now hood. As it needed the gib strip adjusting (or replacing) or more worrying the lathe is too worn. But I think I am able to see if I can solve that today.
As for tool blocks. It is a Dickson holder and I have steel ready to make some. However with my experience that will take days or weeks. Not hours. Lol.
Quickest method would be a tube, welded to a block as a temp solution. But I purchased some indexed milling holders yesterday so I will give them a quick go today.
It's all a big learning curve, so I am grateful for yours and everyone else's input.
It's good to see that I can at least follow the logic.Another idea is shown in a YT video by El Metal Raymond Menendez, called 'Alargador portaherramientas para torno'.
One thing to ponder on when 'overtooling' (or undertooling) any machine is the challenge of setting the cutting tip on centre. On a standard Dickson setup, you can quickly bottom out or top out the adjustment so it it worth checking this aspect before modifying a holder.
With a round boring bar, you can also run out of horizontal depth for the clamping screws, not a problem on square-shanked tools as they do not mind being clamped off centre, but the milled flats on a round bar only extend a set amount.
That video was very therapeutic. I used to love watching Abomb79 with his oversize machining but since he went full time you tube I lost interest.Another idea is shown in a YT video by El Metal Raymond Menendez, called 'Alargador portaherramientas para torno'.
One thing to ponder on when 'overtooling' (or undertooling) any machine is the challenge of setting the cutting tip on centre. On a standard Dickson setup, you can quickly bottom out or top out the adjustment so it it worth checking this aspect before modifying a holder.
With a round boring bar, you can also run out of horizontal depth for the clamping screws, not a problem on square-shanked tools as they do not mind being clamped off centre, but the milled flats on a round bar only extend a set amount.