How tricky would this be to machine? I guess a Triac is not up to the job!

Hi guys this a 316 stainless part in that it fits onto a 25.4stainless tube. I would like to have them bored out to 28.58 or there abouts tofit on a larger diameter tube, it looks like there would be enough meat leftbut I wonder how tricky a job it would be to do. I need to do 14 of them ifanyone has any ideas or advice I would welcome it. I do not know where to start!
Many thanks Attachment 18668
Steve

Hi Steve
Do you have a faceplate for your lathe ?
Mike

Looking at the dimensions you give and trying to scale off the photograph, you are going to leave around 0.8mm wall thickness at the hinge point, or you are going to need to move the axis of the new bore slightly sideways to leave a bit more metal. Is that going to be strong enough for your application? If I were doing this, I might consider a faceplate (if the workpiece is a good shape for clamping) or maybe even look at holding it in a 4-jaw, although I don't know if you could get a good enough hold without marking or distorting the work, especially as the wall thickness reduces. Be interesting to hear how the professionals would tackle it!

Quote:

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Originally Posted by mekanik

Hi Steve
Do you have a faceplate for your lathe ?
Mike

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Hi Mike, thank you for the thought but I don't have a faceplate or lathe! I only have my Triac. I should have said I was thinking of farming the job out once I know what direction to go it or not to go in!
Many thanks
Steve

Hi Neale,
Tar very much for you thougths. Yes I think moving away from the hinge would be good, there is little stress though. 14 of them are just going to hold a plastic panel, that is if this plan wins with my few options for the job. I don't have a lathe so if I see the best way to do it I will farm it out if that is the route I go.
Many thanks
Steve

Personally i would look at away to mill it if possible. Reason is: its hard to define how that clamp was manufactured in the first place. There is a chance it could drop forged and if it is, it will be full of strength in every direction and 'can' be as tough as it gets to machine especially in 316. If its cast it may be better. Like all things like this, you will only know how good or bad it is when you start to machine.

I would steer away from boring due to intermittent cuts, if possible but not essential. Milling cutters are nice and strong and the intermittent cut wont effect a milling cutter. Images can be a bit deceptive but it looks like the rad on the profile does not match the rad center on the inch hole (on the top at least) and it may be very hard to get right in a 4 jaw if even possible. Then you have to repeat 14 times. You could fix it to a separate fixture plate held in a 3 or 4 jaw then calculate the center and put some strategically places dowels to locate it central and use some small clamps, this way you eliminate varying set ups each time, or a variation on this theme would work. A few options to chose from on that theme. In the same breath a plate method could be used to also mill it. The other option if a part dxf is available is to machine the outer profile into soft milling jaws then machine, This would be made a lot easier if the part dxf or similar was available and also cad/cam would help a lot and speed up the process going the soft jaw route. This is how i would approach it as someone in the trade so i don't end up with one launched in my face..... which would undoubtedly hurt a fair bit.

This is an example of a fixture type set up to make life easy.

Attachment 18669Attachment 18670

Here is an example of when a mini pallet maybe of better use:

https://youtu.be/b2qKy43tJcY

.Me

Have you considered machining a pair of aluminium soft jaws for your mill vice? It's a great way to accurately hold oddly shaped parts in the mill.
Machine a pocket across the two jaws that comfortably accepts and supports the part, use a parallel as a spacer to allow you to clamp the vice up tightly with the right gap whilst machining the soft jaws.

- Nick

Hi Spluppit,
Many thanks for such a detailed reply and the attached photos. Having read your reply and having thougth about what you have said I see you have raised some important points and they are of help. I have a good bit to think about!
Many thanks
Steve

Thanks for the link Lee, I have watched the video he is a good guy.
Steve