Hi Phil thanks for the reply and the demonstration showing that coarse wheels make a different sound to fine wheels. I guess the scriber demo highlighted the larger voids in coarse wheels, one of the reasons why they cut cooler. In my experience, I've never encountered coarse wheels grabbing parts more than fine wheels. Once again this seems odd, but grabbing often occurs when parts get hot and expand. This happens more with finer denser grits. I am aware of different wheel hardnesses and how coarse grits leave a larger fillet which was probably not desirable. I am a little disappointed that you once again decided to swerve the advantages and concept of a simple height setting punch which I have used to set location pin heights for almost 50 years. As you sarcastically say maybe I am obsessed and even ocd. I don't think so though, you asked for questions and I supplied one. I do feel this old fashioned method is far more efficient than grinding pins to length and then reaming holes to depth. I just wondered what are the reasons why you do not acknowledge that this is at least an option and why you prefer not to use it. I do like the jig boring reamers, it reminded me of when I used to run a SIP jig borer back in the 80's, we started the tops of the holes with those and followed through with a chucking reamer. Having worked in toolrooms on both sides of the Atlantic I am familiar with bawdy workshop chat and take sarcasm on the chin and indeed like to indulge when appropriate. Thanks for joining in, it seems like I am back at work again. Until the next episode..😉
Do the square-end reamers have a different drill size than normal reamers? I can only find that 2% to 4% of the diameter is left in the hole for normal reamers.
I have a lot of fun with this series but also one more question. During the discussion it came up to do a tighter press fit instead of the d shaped holes to really hold those plugs in place. So I'm wondering now: If I have a flat plate and I press several parts in there with several thou of interference so that I can't just lightly tap it in but I have to use a hydraulic press, maybe even apply some heat to the female end and cold to the male end... the material that interferences has to go somethere. So could I bend the plate out of flat with to much press fit(s)?
Thank you sir What's the best way to make a D shaped hole on a manual machine? A end mill end on an angle? (If the material is thin, like an electronics face plate) Otherwise I'd assume you'd need to bust out the rotary table? Any other tricks to do those quickly on a manual mill without busting out a rotary table?
As far as I know a cnc machine can't really cut a circle. It interpolates a polygone that is so close to being a circle that there is no more significant difference. If you machine a hole for some plug on an electronics face plate you could try that with the manual mill (maybe make a spread sheet with the coordinates and use the dro) but for a precision hole like in that fixture I don't see any other way than the rotary table. And that in itself would be ambitious.
I'm pretty sure the commentor from the video doesn't understand the grinding exercise.... As for how to make a fixture, I would have made a fixture, machined the parts, (20 pcs if I remember correctly?) and moved on with my life while ya'll still arguing about D holes 🤣🤣😂😂 As Phil pointed out we are in the year 2025. You gotta be in the business of solutions if you wanna survive....
There are a lot of stations for 20 pcs and they are not divisible by 10. As you say, make a simple fixture for 1 part and spend the rest of the time making the finished parts on the fixture. I'm sure the client would be delighted with the savings. That is one possible solution to suggest to the client. My preference for non-rotating threads is to use the common threaded insert system of a sliding fit pilot for precision location at the end of the locator and a straight knurl under the head. Only drilling and reaming round holes in the base plate. I can't see how the tiny 0.0025 [96% of reamer diameter] land at the base of the reamed pin holes locates the height of the pins, however small the radius on the end is made. Usually, a piece of scrap machined to the correct thickness is drilled for clearance on the pin and used as a bump stop for the punch.
Hi Phil thanks for the reply and the demonstration showing that coarse wheels make a different sound to fine wheels. I guess the scriber demo highlighted the larger voids in coarse wheels, one of the reasons why they cut cooler. In my experience, I've never encountered coarse wheels grabbing parts more than fine wheels. Once again this seems odd, but grabbing often occurs when parts get hot and expand. This happens more with finer denser grits. I am aware of different wheel hardnesses and how coarse grits leave a larger fillet which was probably not desirable.
I am a little disappointed that you once again decided to swerve the advantages and concept of a simple height setting punch which I have used to set location pin heights for almost 50 years. As you sarcastically say maybe I am obsessed and even ocd. I don't think so though, you asked for questions and I supplied one. I do feel this old fashioned method is far more efficient than grinding pins to length and then reaming holes to depth. I just wondered what are the reasons why you do not acknowledge that this is at least an option and why you prefer not to use it. I do like the jig boring reamers, it reminded me of when I used to run a SIP jig borer back in the 80's, we started the tops of the holes with those and followed through with a chucking reamer.
Having worked in toolrooms on both sides of the Atlantic I am familiar with bawdy workshop chat and take sarcasm on the chin and indeed like to indulge when appropriate. Thanks for joining in, it seems like I am back at work again. Until the next episode..😉
Do the square-end reamers have a different drill size than normal reamers? I can only find that 2% to 4% of the diameter is left in the hole for normal reamers.
Lots of ways to make this fixture. I enjoy hearing the design choices you made and reasons why other choices were not chosen. Thought provoking!
I have a lot of fun with this series but also one more question. During the discussion it came up to do a tighter press fit instead of the d shaped holes to really hold those plugs in place. So I'm wondering now: If I have a flat plate and I press several parts in there with several thou of interference so that I can't just lightly tap it in but I have to use a hydraulic press, maybe even apply some heat to the female end and cold to the male end... the material that interferences has to go somethere. So could I bend the plate out of flat with to much press fit(s)?
Thank you sir
What's the best way to make a D shaped hole on a manual machine? A end mill end on an angle? (If the material is thin, like an electronics face plate)
Otherwise I'd assume you'd need to bust out the rotary table?
Any other tricks to do those quickly on a manual mill without busting out a rotary table?
As far as I know a cnc machine can't really cut a circle. It interpolates a polygone that is so close to being a circle that there is no more significant difference. If you machine a hole for some plug on an electronics face plate you could try that with the manual mill (maybe make a spread sheet with the coordinates and use the dro) but for a precision hole like in that fixture I don't see any other way than the rotary table. And that in itself would be ambitious.
mill a slot adjacent to the hole and fit a key in it.
I'm pretty sure the commentor from the video doesn't understand the grinding exercise.... As for how to make a fixture, I would have made a fixture, machined the parts, (20 pcs if I remember correctly?) and moved on with my life while ya'll still arguing about D holes 🤣🤣😂😂 As Phil pointed out we are in the year 2025. You gotta be in the business of solutions if you wanna survive....
There are a lot of stations for 20 pcs and they are not divisible by 10. As you say, make a simple fixture for 1 part and spend the rest of the time making the finished parts on the fixture. I'm sure the client would be delighted with the savings. That is one possible solution to suggest to the client.
My preference for non-rotating threads is to use the common threaded insert system of a sliding fit pilot for precision location at the end of the locator and a straight knurl under the head. Only drilling and reaming round holes in the base plate.
I can't see how the tiny 0.0025 [96% of reamer diameter] land at the base of the reamed pin holes locates the height of the pins, however small the radius on the end is made. Usually, a piece of scrap machined to the correct thickness is drilled for clearance on the pin and used as a bump stop for the punch.