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Anyone here who has removed the compound and replaced it with a riser block?

Domodude17

Aluminum
Joined
Aug 14, 2017
I'm debating removing the compound on my 9A and replacing it with a riser block. I've heard it improves rigidity and finishes, and I don't really use the compound much at all. How do you feel about the change?

Other reason i'm asking is because if I do decide to remove it, I need to buy a block of metal no matter what. I know cast iron somewhat has vibration dampening properties, but i'm not sure i'd be better off with that or just a block of steel. Not sure if it'd even make a difference? Thoughts?
 
in my perhaps controversial opinion, provided all is properly adjusted,there is little you can do to the SB9 to increase "rigidity".....making the SB9 perform is ALL about the cutting tool, there is nothing rigid about the SB9" and if you eliminate flex in one area it will just transfer somewhere else...really good sharp tools is where it's at.:)
 
Tightening the gib adjustment screws when not using the compound would have a very similar effect on rigidity and be a lot cheaper and easier. This is even more true on a SB 9 because it has a straight, non tapered, gib on the compound so all the play can easily be removed from the slide even if it's badly worn.

Sure, taking the compound out of the equation and replacing it with a solid block does improve rigidity, and it's not totally uncommon for folks to do that on heavy machines they intend to use to their full capacity in production. However, being this is a SB 9 we are talking about and the rest of the machine is about as rigid as a an overcooked noodle, I can't see it making much difference in the big picture here. I'd say it's certainly not worth the time and materials to do so.
 
I made a solid block for my old 10k which is probably as rigid as a 9a. The block did make a difference especially when parting steel. I used carbide mostly with my old lathe successfully. Rarely used HSS.

I made the block utilizing the South Bend taper pin mount so I could easily swap the compound back on if I needed to. The block was made from A3 tool steel that was 20-25 Rockwell C. I could of had it hardened but the as received hardness was acceptable. I drilled and tapped 3 tool post stud mounting holes, one centered over the taper pin and two spaced at 1” and 2” back. In doing so I could move the tool post rearward to accommodate larger diameter stock and still use the Dorian post. I was very happy with the increased rigidity until I sold the lathe and bought a Heavy Ten.

I had also made a mount system to put a dial indicator in the X axis. Just had to remember 0.001” was radius not diameter! Missed once but fortunately didn’t scrap the part!![emoji2]

So far the Heavy Ten doesn’t seem to need the block but I do intend to adapt it over to the Heavy Ten pin so I can use it if necessary.

Here are a couple pics of the block on the lathe.

928e87f6e5277c78b25c2b1fa8515a58.jpg


87b23fb9abe9e7ca8d896fc817019d1f.jpg



Sent from my iPhone using Tapatalk
 
Same thoughts about machine rigidity as others, but to comment on the QCTP, when I have a job needing maximum rigidity, I replace the QCTP with a lantern tool.

Tom
 
Tom there was a picture somewhere on the forum of an Armstrong #6 tool holder,think it uses 3/4" cutter, with the lantern post choked all the way up pulling out a huge chip on a big lathe. That arrangement puts the cutter in the center of the slide instead of hanging over one side or the other like a QC post.
 








 
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