Cast brass for lathe parts?

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Water-mark
Posts: 20
Joined: Tue Jan 03, 2017 2:09 pm
Location: England UK

Re: Cast brass for lathe parts?

Post by Water-mark »

Dragging this out of the depths for an up date.

I made up two brass back plates and fitted a 3 jaw and an er32 collet chuck to see how they went.
I've not used the 3jaw much but the collet chuck has seen some action right up to the maximum capacity and is still running well depite some fairly heavy intermittent cutting of rough cast.

I've also made a compound slide up and that seems good also though i only put it on to use it and then remove when done.

So for future reference cast brass is good for small lathes (mine is a 3" randa), not sure at what point it becomes unsuitable though.
John Hasler
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Joined: Tue Dec 06, 2016 4:05 pm
Location: Elmwood, Wisconsin

Re: Cast brass for lathe parts?

Post by John Hasler »

SteveM wrote: Tue Jan 03, 2017 5:13 pm I'm no expert, but cast iron has dampening properties that brass (and even steel) doesn't have.

I've been told you can use Fortal aluminum as a backplate (I think it's 7075).

Using brass for a backplate may work, but there may be unwanted vibrations that will show up on the workpiece.

If it's all you've got, it may be better than nothing.

Steve
He will certainly have less trouble with vibrations with brass than with aluminum. I think that the only problem will be that brass will wear a little faster than steel or iron.
jpfalt
Posts: 982
Joined: Sun Jan 05, 2003 12:55 pm

Re: Cast brass for lathe parts?

Post by jpfalt »

It would be better to use bronze for wear contact surfaces as brass wears faster and galls worse than a lubricated bronze. There are a lot of different bronze alloys. Bearing bronze is readily available in scrap plain bearings and casts well. You may also be able to get bronze valve bodies. The easiest way to check whther the alloy is brass or bronze is to heat a small sample with a torch and if you get the very light green flames burning off from the melted metal, you have brass. The flames are from burning zinc used in the brass.
Water-mark
Posts: 20
Joined: Tue Jan 03, 2017 2:09 pm
Location: England UK

Re: Cast brass for lathe parts?

Post by Water-mark »

Thanks
I haven't come across any bronze scrap in ten years as they tend to be more commercial size valves.

I might make a back plate for my newly aquired 9" lathe out of brass to practice cutting the threads.
Glenn Brooks
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Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: Cast brass for lathe parts?

Post by Glenn Brooks »

Yes, definitely go for the lottery. Also, look for a 4 jaw 5” chuck for my old Dalton lathe please. Undoubtedly you have the gift!!

Glenn
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: Cast brass for lathe parts?

Post by Glenn Brooks »

Yes, definitely go for the lottery. Also, look for a 4 jaw 5” chuck for my old 1919 Dalton lathe please. Undoubtedly you have the gift!!

Glenn
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
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