mounting a 5 inch dia. aluminum on mini lathe???

[Matterest]

Hello,
I am working on converting a compressor pump to a 4 stroke engine, the head of the compressor is ~5 inches in diameter. My question is how can i mount a 5 inch piece of aluminum (for new head) in my 7X14 mini lathe?
Thanks,
Matt Whitehouse

 

[Swifty]

Can you fasten some type of spigot to it that you can hold in your chuck whilst you machine the head. Of course, the spigot will have to be removed when finished and any fastening holes plugged if they interfere.

Paul.

 

[Matterest]

maybe, how would i center the hole for the spigot though?
i wish i had thought about that 3 hours ago...

 

[trev1]

Make up a plate with holes in it that matches the hole pattern of the compressor head, center the holes, and drill a hole in the center of the plate to suit the biggest bit of bar you have spare. Now, tack weld the bar into the center hole, true it up in the lathe ( spin it slowly to check) , once true, fully weld it. Once fully welded, face the plate off in the lathe, bolt up your job, and start machining.

 

[Hopper]

Bolt it to a faceplate? Or do mini lathes not have a faceplate?

 

[trev1]

Bolt it to a faceplate? Or do mini lathes not have a faceplate?

I dont know, but maybe best to get help with this project if you have had trouble already.

 

[Matterest]

The mini lathe does have a faceplate but im not sure its big enough and I dont have one
:wall:

 

[ShopShoe]

FYI: The Mini-Lathe Faceplate

http://www.littlemachineshop.com/products/product_view.php?ProductID=1199&category=

--ShopShoe

 

[kf2qd]

I have turned a larger diameter by putting 3 hole in the face of a part and grab it in the 3 jaw.

 

[Hopper]

A good book for you might be Tubal Cain's "Workholding in the Lathe". It seems with the smaller lathes there is always a constant struggle to fit something bigger or more awkward in the limited holding capacity. But there is always a way and I am sure the old Tubal Cain knew most if not all of them.

 

[///]

Turn up a mandrel and use wax or some other heat sensitive adhesive(like Shellac) to glue the plate to the mandrel.
I have done this successfully to 7" dia on a minilathe.

http://www.homemodelenginemachinist.com/f25/all-about-wax-chucks-15752/

Keep in mind, the larger the contact area the safer it will be. You will be surprised how strong a 2 or 3" wax chuck will grip.
BUT, err on the safe side if using wax: keep work loads to a minimum with many light cuts rather than fewer heavier ones, and also keep an eye on the temperature of the workpiece so as not to soften the wax and have the work fly off at xxx RPM.
Shellac has a higher melting point than wax, approx. 80-100 deg C, softening about 50 C.

 

[Swifty]

Have used double sided carpet tape before for milling, it's very thin and sticks well. The biggest problem is getting it off whatever it's stuck to. If you do it this way, just be very careful, when tape is used on a mill and comes unstuck, not much harm is done. But if used on a lathe and let's go, things could get nasty.

Paul.

 

[gus]

Hi Matt,
Did this to turn a C.I. flywheel. My Sakai mini lathe was stretched to turn this f/wheel and could take only shallow cuts and feed.

 

[Jasonb]

If you drill and tap the head mounting holes smaller than their final size you can then bolt the embrio head onto a piece of scrap plate which can in turn be drilled to suit your faceplate.

I did something similar with this head casting but was able to hold the plate in my large 4-jaw.

Once the turning is done you can drill out the mounting holes to their final size.

More details here