Question For Dave McCann and Any Other Machinist
- Thread starter Eric Patterson
- Start date
Richard Lathrop
Well-known member
What is the final turned diameter? Tangental cut means 1 7/8" minus diameter to get height of the cutting edge of tool above cross slide deck?
Rick
Rick
Richard
Final dia. about 1 1/2" - 1 3/4". There's enough room. But you can see why in the original picture why they had the tooling flat on the cross slide.
Final dia. about 1 1/2" - 1 3/4". There's enough room. But you can see why in the original picture why they had the tooling flat on the cross slide.
Eric
What width would you need the tool steel to be to cut the profile? Wider than the 4 inch width of the cross slide deck?
(A) Thickness of the tool steel profile cutter:
Given the 1.875 distance from the deck to lathe centerline, minus a radius of .875 (workpiece diameter of 1.750) leaves 1.00 inch minimum thickness for the tool steel. This should provide plenty of strength to the cutter.
(B) Clamping lugs:
How accurate are the Tee slot dimensions I have shown (1/4 by 1/4 by 1/4)?
Assuming a height above the deck to the top of the clamping lugs to be .625 should provide adequate material for a draw bolt hole. The lugs could very well be made taller ( and probably should be) to accommodate more tool steel material under the clamping bevel. Not sure just where the best height would be, while still keeping the lug as low as possible to avoid any interference. Not sure if interference would even be an issue, as I would not expect the clamping lug to ever get to the point of tangency with the workpiece.
These again are just rough sketches. I'm not a designer or mechanical engineer, I just build the stuff.
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Dave
You have almost enough info there to satisfy a machine shop. You have done this before
. In all seriousness I am most thankful for your help.
I'm off today and am at the shop taking measurements. I cannot ever see cutter width exceeding 4" and 3"- 3 1/2" will be the norm. Also the largest finished diameter will be under 1 5/8" and typically 1 1/2". The smallest diameter is 5/8" if I make inserts by knife. If I just make barrels then 7/8".
Your "T" dimensions are close. I have a t-nut in my hands. The bottom wider portion is .265 thick and 1.515" wide. The top portion is .225 thick and 1.22" wide. If you change these dimensions and show the side with the angle portion I think the clamp design is good to go.
I'm in discussion with a tooling company about the cutter. I may call you with a few questions about that. Thanks!
You have almost enough info there to satisfy a machine shop. You have done this before
. In all seriousness I am most thankful for your help.I'm off today and am at the shop taking measurements. I cannot ever see cutter width exceeding 4" and 3"- 3 1/2" will be the norm. Also the largest finished diameter will be under 1 5/8" and typically 1 1/2". The smallest diameter is 5/8" if I make inserts by knife. If I just make barrels then 7/8".
Your "T" dimensions are close. I have a t-nut in my hands. The bottom wider portion is .265 thick and 1.515" wide. The top portion is .225 thick and 1.22" wide. If you change these dimensions and show the side with the angle portion I think the clamp design is good to go.
I'm in discussion with a tooling company about the cutter. I may call you with a few questions about that. Thanks!
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Eric,
I really don't know my way around the design program but here is what I have. It looks a bit different because I have left more material in the Tee slot area. I believe I have provided all the info needed to build the clamp prototype.
I will work on the dimensions for the clamp bevel cut into the tool steel.
I would suggest you build a wood model of both the tool steel and the clamps, to prove out the dimensions when I get the rest to you.
I really don't know my way around the design program but here is what I have. It looks a bit different because I have left more material in the Tee slot area. I believe I have provided all the info needed to build the clamp prototype.
I will work on the dimensions for the clamp bevel cut into the tool steel.
I would suggest you build a wood model of both the tool steel and the clamps, to prove out the dimensions when I get the rest to you.
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Dave
If you don't know your way around the design program you've done a great job of convincing me otherwise. I take it you did these with the free version of Fusion 360 you've mentioned in the past.
We are on the same wavelength. I am going to make wood prototypes. Quick question. Why the .531 bore for a 1/2" bolt?
Thanks again for all your help.
If you don't know your way around the design program you've done a great job of convincing me otherwise. I take it you did these with the free version of Fusion 360 you've mentioned in the past.
We are on the same wavelength. I am going to make wood prototypes. Quick question. Why the .531 bore for a 1/2" bolt?
Thanks again for all your help.
Just general machine clearance for bolt holes. 32nd of an inch is common for the thru hole. Actually a 1/2 inch bolt may be overkill. 3/8 might be sufficient.
Yes, using the free version of Fusion. My learned skill set is lacking for what I'm trying to accomplish. Took me several tries to generate those and I'm pretty sure I went the long way around the block. Sometimes I do something and then don't understand what exactly I did to accomplish it and even more, how do I change it.
Eric,
Would like to know this dimension on the cross slide. It is going to be thicker than the tee nut thickness you stated. "The top portion is .225 thick and 1.22" wide."
It is otherwise the t-nuts would be ineffective at locking onto the cross slide. I'm headed to the shop in a bit to load up the boat before I go hunting this afternoon. I'll post that dimension.
Dave
That measures .220. Turns out the t-nut that just came in the mail is a tad proud.
That measures .220. Turns out the t-nut that just came in the mail is a tad proud.