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  #11  
Old 08-16-2006, 07:54 AM
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DanH DanH is offline
 
Join Date: Oct 2005
Location: 08A
Posts: 9,500
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I've run an older Smithy for about 10 years. Can't imagine getting along without it. I have purchased a lot of tooling here and there as needed to meet some particular job, and that will run up your total investment. However, the same is true regardless of what lathe or mill you buy and lot of the tooling will work with any future machine.

The Smithy is really useful for turning out small parts quickly, things like axle spacers, tailwheel bushings, wheel pant hangers, and bearing stops. I also use it a lot to simply square the end on a tube, or the end of a mandrel. These kinds of parts don't require extreme accuracy. When I need .0005 accuracy (like a perfect shaft fit in a bearing) I throw a rag across the bed to protect it and switch to abrasives for the last fuzz of material removal. A right angle die grinder running a 3M deburring pad can be used like a hand-held tool post grinder. Internal blind bores at the .0005 level can be done, but you spend a lot of time and cross your fingers for luck.

The mill function is useless for large surfaces. Not enough bed travel in any small lathe/mill. Also, all the lathe/mill combinations require that the part be elevated a good bit above the bed, which introduces flexibility.

The advertised swing is misleading. The practical limits are about 6"D for aluminum and maybe 3.5"D for steel. You can't slow the spindle enough to get a reasonable cutting speed. Smithy does sell a planetary speed reducer pulley, but it is junk. I killed two of them and started taking larger diameter jobs to a friend's house to cut on his big lathe.

Which brings us to a side advantage. Turn out nice parts on your Smithy and pretty soon the other lathe and mill owners in your area offer to let you use their larger machines when needed. A Smithy is a great training tool because you must think your way around how to get the job done, and as it is belt driven, gross cutting errors tend to result in belt slip, not broken parts.

None of the above is to say you can't turn out significant work. I've used mine to build a complete propeller speed reduction unit, an experimental viscous torsional vibration damper, wheel hubs for WW1 replica wire wheels, you name it.

I think buying one depends on what you see in your airplane future. I TC a lot of projects and assist with a lot of repairs, plus my airplane world includes custom tube and fabric. Right offhand I can't think of very many parts I've made for RV's.

Dan Horton
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  #12  
Old 02-09-2011, 03:03 PM
wjnmd wjnmd is offline
 
Join Date: Mar 2006
Location: Ft Myers, FL
Posts: 276
Default Follow-up questions

My next project is a Marquart Charger ( Two-place open cockpit biplane similar to a Skybolt or Starduster Too. Tube and fabric construction). I need a good method to notch tubing and it appears a mini-lathe would be adequate. I bought an Ol' Joint Jigger but I find that it binds on the tubing while being used in my drill press. Does a mini-lathe sound like it would be adequate? Other suggestions?

I'm not much of a metalsmith but I'm always looking for a new way to expand my workshop. My motto: "Always pick a project that requires the purchase of at least one new tool"
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  #13  
Old 02-09-2011, 03:56 PM
rv9aviator rv9aviator is offline
 
Join Date: Jan 2005
Location: Arkansas
Posts: 1,505
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I would think a mill would be a better choice for notching tubing. You can do mill work in a lathe with the right attachments too though. A mill with a tilting head would be my choice.
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  #14  
Old 02-09-2011, 04:36 PM
Daver Daver is offline
 
Join Date: Nov 2006
Location: Albuquerque
Posts: 297
Default Smithy

I have a Smithy 1220XL.

It came in real handy for making spacers and other odds & ends for my -9A build.

Its made in China but I think its pretty good.

The company is really good. I broke a couple of gears while trying to cut threads on some round stock. This thing does not have limit switches

Cutting threads on a screw cutting lathe will make you really appreciate a hardware store bolt you can buy for a buck or two.

Anyway, Smithy replaced the damaged gears for free.

My Dad & my wife went together and bought it for me about 10 yrs ago.

Dave
-9A flying
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  #15  
Old 02-09-2011, 05:05 PM
PaulR PaulR is offline
 
Join Date: Oct 2005
Location: Geneva, AL
Posts: 491
Default Mittler Brothers

You might check with Mittler Bros. We have a heavy duty notcher at work but the link is for a lighter duty notcher. They are a great USA company.

http://mittlerbros.com/hole-saw-notcher.php
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  #16  
Old 02-10-2011, 05:21 AM
N601RX N601RX is offline
 
Join Date: Nov 2009
Location: Troy, Al
Posts: 17
Default Bridgeport

The Mill will be much more useful than a lathe. Most anything that can be made can be made in a lathe can also be made on a mill. The oposite is not true. I have full size floor models of both and seldem use the lathe. I use the mill all the time. I personally would rather have a 30 or 40 year old Bridgeport than a new china made one. You can also invest a lot of money in tooling so it often makes sense to find a used one that is being sold with tooling. A digital readout is a must in my opinion.
There are a lot of cheap Bridgeports on the used market as they have been replaced with cnc equipment in large shops. There are a few things you need to look out for, so if you find something send me an e-mail and I'll point them out.
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  #17  
Old 02-10-2011, 08:40 AM
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scard scard is offline
 
Join Date: Jun 2005
Location: Cedar Park, TX
Posts: 3,156
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I have a JMR notcher. It is a work of art.
http://www.jmrmfg.com/store/JMR-Tube-Notcher

The company is great to work with too. They know their stuff. Their hardened saws are light years better than standard stuff you would use around the house.
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