I'm new and need advice. Look at my prints and suggest some machines please!

If the flange and drill holes don't have to be really precise it looks to me like most like most of your project could be done on a lathe with a 4 jaw chuck and a drill press or even a hand drill.

Cheaper than a mill, if your milling needs are secondary you might consider a large mill drill like a Rong Fu RF-31 and save most of your budget for a lathe. Several here have them and they seem quite capable of doing decent milling, it just takes more care. You see them pop up used far more often and cheaper than other mills of this general size because the round column is considered less desirable.


The originals are made by Rong Fu but there are lots of clones like this one from Grizzly.

https://www.grizzly.com/products/Grizzly-Mill-Drill-with-Stand-29-x-8-Table/G0705


Here is a used Jet version in Oxnard for $1100. Since they are keeping the vise and tooling you might be able to talk them down to $800-900, maybe less if they want it gone. Jet is a quality brand.

https://ventura.craigslist.org/tls/d/thousand-oaks-jet-mill/6849861221.html
 
Going back to what benmychree said about material, and an assumption this is an air cylinder or something similar, you might consider honed cylinder tubing. Also, with such thin walls, 6 jaw chucks start being a realistic necessity to hold the tolerances you are looking for - as previously stated, tooling is the other half of the expense problem. Changing to sized material may reduce your tooling costs, if you can work around the design changes to accommodate it. You are weighing lots of variables that we don't always have to deal with on the design side of the problem - but those on the fab side deal with all the time (and creates tension between the two "factions"). This excercise, even if you punt, will make you a better designer. Good luck
 
If you are only looking at machines to achieve the current project, I consider that a mistake, unless you do not plan to use them for other shop work after the project we are discussing here. If you plan to do more machining later, think also about what will best suit your needs and wants longer term.
 
GL said:
Going back to what benmychree said about material, and an assumption this is an air cylinder or something similar, you might consider honed cylinder tubing. Also, with such thin walls, 6 jaw chucks start being a realistic necessity to hold the tolerances you are looking for - as previously stated, tooling is the other half of the expense problem. Changing to sized material may reduce your tooling costs, if you can work around the design changes to accommodate it. You are weighing lots of variables that we don't always have to deal with on the design side of the problem - but those on the fab side deal with all the time (and creates tension between the two "factions"). This excercise, even if you punt, will make you a better designer. Good luck
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I like this. There will be no punting. I always supported the guys in the shop with whatever they asked me for, including hole tables or any dimensions they wanted because I always respect the work they do. I understand the carefree mentality that designers sometimes have; "They will make it work" comes to mind.
Anyway, I see what you are saying about that thin wall. How can you even grab it without bending it? I can make that part a completely different way. I can buy two pieces of tubing close to finished size, clean up the OD of the smaller one to fit in the larger tube, cut it to length and EPOXY that sucker inside the other tube. It will work. There is no axial stress on that part. Just a little pressure from inside and a little more from the outside for about 15ms. Pretty weak. JB Weld can do the job for me if necessary. Only for that part though.

The machines aren't for just this project. They are for all of my hobby needs. Also, once I have the machines it will open the door to more projects and maybe even a little side work doing small little jobs for friends. Right now there is no door because I don't have the machines yet. This will change.
 
I wonder how you are going to check the parts. And I wonder if you Are able to cut the o’rings and get a good finish on them how will you be able to check locations on them. And how to check dia of o’rings inside the counter bores. And where are you going to get the tool bits to cut the o’rings. What do you have to check the lengths of parts. And I wonder how much out of round the stock is and how will you get it round? These are skills it took me years to learn.
And I think you need extra stock to practice on.
If I were you I would try to make the end cap first. To see how it comes out.
 
Aaron_W said:
If the flange and drill holes don't have to be really precise it looks to me like most like most of your project could be done on a lathe with a 4 jaw chuck and a drill press or even a hand drill.
Click to expand...

Thats what I was thinking looking at it also.

The angled edges depending if they are cosmetic or require precision, you could use some sort of belt sander or a file. (or flap wheel on an angle grinder perhaps)
 
Some thing to think about. Just because a lathe says it will turn a ten, twelve or whatever size it says it can turn doesn t mean it will do what you want. The swing is given over the ways so gets drastically reduced over the crosslide. For example my 14-40 lathe will only turn just under nine inches over the crosslide. Reversing your jaws in the chuck may hold the six inch shaft but will the jaws clear the crosslide and ways? These questions need to be asked before you purchase a lathe.
 
For the mill don't consider one that doesn't have a DRO. It will reudce mistakes and increase your accuracy without spending the years it takes to be competent on a mill. Use small cutters such a carbide 2 flute made-for-aluminum milling cutter. They will be expensive, but worth it.

Expect to waste money on material to rework things until you get them right. None of this machining stuff is magic or easy. It takes practice to get accurate work. No first-timer produces perfect parts out of the gate. It's okay to make mistakes.
 
moonbogg said:
The machines aren't for just this project. They are for all of my hobby needs. Also, once I have the machines it will open the door to more projects and maybe even a little side work doing small little jobs for friends.
Click to expand...


Thats the spirit, you are now welcomed to the machinery addiction club , can we put a friendly wager on the time it will take before you realise you want (I mean need) a welding rig or perhaps a sheet metal brake ? ;)

Stu
 
I always recommend getting the biggest and best you can afford and have room for. You will always find a job bigger than you have envisaged. I had to settle on a 12 x16 because that is all the room I have available, If I could have got a 12 x 20, but the next size up was 12 x 24, so too big.

The next decision was quality and price I looked at all the cheap chinese lathes and decided not for me. I have a lifetime of machining experience, and I could tell just by the look and feel of them that I would have been very disappointed if I had bought one. I finally settled on a Taiwanese made lathe very good quality about 25% dearer for the same specs, but I am very confident that it won't let me down.

Yes I had to increase my budget from $4000 to $5000 but in the end I think it was worth it. PM do have some very similar lathes to this that do come from Taiwan. I hear on this forum that they are very good, and so is the after sales service. As for a mill, again I don't have room, so I do all my milling functions on the lathe.

God luck whichever way you go, and never hesitate to ask on this forum
 
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