Thread: Machinist's / hobby machinist's

I'm a very amature hobby machinist, early stages of learning to run a lathe and mill. I have noticed quite a few hobby machinists etc on this forum, its probably somthing in gun owners personality that attracts them to building things, its the same as motorcycles, i have noticed many people that shoot also ride.

Any way, is there a nz based forum or Facebook group that people use, I have come accross lots of overseas stuff but it would be great to discuss things with local people to see where people are getting supplies etc, most forums just point you to American websites and there freight charges are just over the top.

Also does any one know where I can get a backplate for a 5 or 6 inch chuck for a 9x20 lathe, it has the M39x4 spindle thread, I emailed machinery house who I got it from, but they were not to helpful, I could machine it myself but I believe I need to make it from cast iron and I have no idea where to get a piece that size.

Cheers
Russell

Good place for supplies https://www.carbidenz.co.nz/

I have always managed to find what I need, but feel like I'm paying a fair amount as Im not in that trade, Im just curious if there are better places around to get stuff, places that are setup better for hobbiest types , obviously you can get the real cheap stuff from China, which for one off jobs has worked. Are most people using expensive quality stuff from engineering shops or is there a middle ground?

Cool didn't know fletcher would sell by the m, I used to go donavans but since they moved I have been going to bindons.
I'm trying to go hss, I use some cheap carbide bits but want to set myself up for hss better. Things like tool holders and I want to get a 4 jaw chuck, bits like that are you looking through engineering shops or more like machinery warehouse, I have bought all my lathe specialised stuff through them but I'm thinking allot of the tooling/chucks is just the stuff we see on the ali baba website rebranded.

The Chinese end Mills that came with my mill/drill are pretty rubbish, I have only used them on aluminium and you can already see they are not really concentric.

Sparey's book on the amatuers lathe is good value. A cheap 16mm set of TC insert tooling is offered on TradeMe which is perfectly useable. I keep a good stock of HSS which is good to grind into form tools as required. A QC toolpost with a clump of extra tool holders is a real time-saver. A circle of 25mm steel plate won't cost much from your local profile cutter and will make a good backing plate. When it comes to drills, milling cutters, etc. then always buy good respected brands - dearer to buy but better value in the long run.

While i agree to a point on the mills and end mills being lesser quality from china,Myself and others in the trade all source the carbide from aliexpess or alibaba at a tenth of the price paid here.

My new lathe has only been here 2 weeks and uses 20mm tooling so early days on carbide life but they are so cheap i think it is a non issue.I have two friends who do this for a living over the last twenty years and only use hss if it is soft like brass alloy etc as it stops the chips coming back at you like carbide.One refuses to use hss as the speed he can cut and remove material with carbide is far more efficient.He is also taking 8mm off in a single pass on some jobs !!

I use flood coolant on most of the jobs and playing around and still on the original tips after two weeks.I guess carbide life would depend a lot on type of material cut and keeping the work and tips cool.

Yep, there is nothing than can't be done by HSS, especially by grinding the tool rake to suit the material. TC has only been commonly available since the 1960's. For the 100 years prior to that it was all done with HSS (including the engineering output of two World wars). I don't think you can find much fault with the quality of engineering up to and including WW2.

Carbide easier to chip if material nasty or you are a bit rough but in general it can cut at 3x the speed of hss.
Hss better for mild steel at least as far as final finish goes. The softer materials like that. Better for nylon too and if you cat aluminium use a bit of crack or kero and has does well.
Dont believe it's better than carbide on brass. It's all about the rake.
Dont be frightened of aliexpress tool holders but if you are that worried put good tips in there.

My machine doesn't really have the hp to do deep cuts, it's just a light machine, not sure my skill level is going to be any where near building a 4 jaw, maybe one day, I was thinking a back plate was a stretch. So far only done stuff with simple dimensions and no real threading.

I searched the country for 6-7 months before I found something decent with a cast bed to replace my small lathe.

Originally Posted by Markgibsonr25

I searched the country for 6-7 months before I found something decent with a cast bed to replace my small lathe.

That is a great looking machine, I hope to one day get to some thing like that, I'm quite happy with my small bench top machine for now, it can scare me enough.

Always someone with a bigger one at the trough!!!!

Originally Posted by mimms2

I could probably get that thing between centers and turn it to chips.... [/LIST]

Did a little bit of machine work on a lathe with a nearly 6ft faceplate/4jaw. It had a recess in the floor so could swing almost 4ish meters? Probably 5 or more? Cant remember
Almost...almost put a pc1000 (100 ton) excavator spider frame in it to face the slew ring mount surface but the corner of the office that was put in a few years before stopped it