mini machine capabilities

[carl86]

I an new to these mini machines and have a few questions.

Are the 7x lathes and the 2x mills capable of machining a stewart #10 casting kit engine

or could tell me about there material removal rate(al or mild steel),depth of cut ,cutting feed speed ect.

Im planing on buying a Micro Mart 7x16 lathe and there R8 mill

thank you
Carl

 

[Lakc]

I cant give you a specific answer to your questions because I do not have either machine or the engine, but I suspect you will find most limitations depend on your resourcefulness and ingenuity, which is generally given out free here. ;D

Metal removal rate scales with the size of the machine. Beyond that general statement you need to add tons of qualifiers for setup, materials, tooling etc. Suffice it to say it will likely be slower then a Bridgeport and probably faster then a Sherline. As great models have been made with all the flavors of commercial machines out there, it is more about the operator.

 

[carl86]

Thank you Lack ,I understand your reply but I was looking for an answer from

someone with experience building engine models with this size machines.

 

[Cedge]

Having owned and used both machines from Micromark, I would not foresee any real problems building the Stuart 10. The machines offer plenty of working room for a small build of that size. As mentioned above, it's as much about the builder's capabilities as it is the machine used.

Steve

 

[carl86]

Thank you Cedge

 

[pete]

Carl,
Two very important points that seem to be glossed over or neglected in various forums and magazines. While building any engine or any object with multiple moving parts it's really critical that your parts are true to size within working limits, Items such as the piston bore to the crankshaft are built and fixtured at a true 90 degrees ect. I really can't stress how important that is for a free running engine so it doesn't bind up during operation. Proper alignment of your new lathe and mill is also just as, and maybe more important. You have no idea (yet) What a complicated yet rewarding hobby your about to start. That's not meant to intimidate you, Just to give you at least some idea of what or how some of your perceptions are going to change. One more point, Spend everthing you can afford on books about machining. You will return to these time after time for referance.

Since I got started typing this it occured to me that I should include two more items that will in the long run save you some inaccurate or poorly machined parts, Buy the very best quality of measuring equipment you can afford, And even more important buy top quality cutting tools. With either of the above two items you do get EXACTLY what you pay for. To start with, the cheaper cutting tools would be best as you will ruin a few while learning. After that, Buy one high quality end mill or even a very good quality piece of high speed steel for your lathe, resharpen that and you'll fully understand what I mean. Dirt cheap cutting tools generaly mean poor or low cutting tool life and cutting performance. All high speed steel or carbide is "NOT" the same between high and low prices.

Pete

 

[HS93]

There is one point to remember when starting out and that the machine is sometimes the cheap part it's the tooling you need to go with it , fortunately this has come down in price but as I am relatively new I still find I need different taps dies for new projects and the odd piece of tooling .as has been said some half decent setting out tools, this is an area I neglected and am now having to rectify this to get better accuracy, you do not need the tooling all at once it builds up as you go , and if you keep doing the same type of thing, like different Stuart kits once you get set up to do one you will probably not have to but very much bar the odd tap or die.I had the old two bar emco lath and I found that could do most things if you put your mind to it, I read a book that showed you could build the L C Mason Mini traction engine on it and that made me look at it in a different light. (worst thing I ever did was to sell that lath/mill )

Peter

 

[Tin Falcon]

Carl:
I have a mini mill and mini lathe I also have a 10H kit sitting in the wings. I do not see any foreseeable problems but I have not actually machined the kit yet.
Get yourself a speed and feed chart and use it. Speed is determined by the material and the diameter of the work in the case of the lathe and cuter in the case of the mill, and cutting tool material. Feed is related to the speed. Depth of cut will be determined by the machine and the tooling. Use quality sharp tools and the machine will do well. not a Bridgeport but they are capable of building fine models.
I suggest you build a bar stock engine first and or of buy the build book.
Tin

 

[carl86]

Thank you all for your replies

I should say that I am not new to machine shop work,
back in the 60's and 70's I set up and operated very large milling
boring machines and also worked in quality control for thirty years.
I am retiring soon and want to set up a small shop to build model engines.
What answers I am looking for is can I take (for example) a .025" depth
of cut on 1020 steel with a 1/2" end mill or .020" depth on the lathe?
I just using these as examples to get some idea on what these machines
are capable.
Thank You
Carl