Why Cast Iron?

[Rustrp]

I'm not following your KISS approach. Do you have an idea to simplify the build? If so, I'm all ears (or eyes, since I would be reading it). I plan on making some other changes to the design anyways. I plan on making the collet holder for R8 collets that I already have for the end mills I use. That way I don't need to make a bunch of new collets. I did the same thing with the end mill end sharpening block I made before and that worked well.



Looks like I better rethink using steel. I would hate to go through all of this and find it doesn't work well or galling starts and then I have to make more new parts. Better to do it right the first time. Guess I'll stop by one of the machine shops in the City next time I go in and see if I can scrounge some small cast iron pieces.

Thanks for all the feedback. It sure pays to ask questions and have a support team to help out with answers.

KISS being an acronym for; Keep It Simple Stupid and not meant as sarcasm from me. Applying it to Hall's hame page, he states that his approach is for projects directed towards the hobbyist, so his cast iron choice as a bearing only requires machining the cast iron to the tolerances you desire. i.e. There's no special drilling, retainers, pins, for sealed bearings, etc. That's as simple as it gets. The most you would need for lubrication if you choose to add it would be some spray or powder graphite which would add nothing for grinding dust to stick to and gum up the works.

As I've responded I keep thinking about the 50 ton punch press I tossed in the scrap bin six months ago because the frame was cracked. It was no longer any good as a press but would have done many projects such as yours. *&^%#%^&**expletives!

 

[Tony Wells]

Mr. Hall is a member here, and should be able to clarify any concerns you have regarding his design intent or reason for making this component from a certain material.

 

[HBilly1022]

KISS being an acronym for; Keep It Simple Stupid and not meant as sarcasm from me. Applying it to Hall's hame page, he states that his approach is for projects directed towards the hobbyist, so his cast iron choice as a bearing only requires machining the cast iron to the tolerances you desire. i.e. There's no special drilling, retainers, pins, for sealed bearings, etc. That's as simple as it gets. The most you would need for lubrication if you choose to add it would be some spray or powder graphite which would add nothing for grinding dust to stick to and gum up the works.

As I've responded I keep thinking about the 50 ton punch press I tossed in the scrap bin six months ago because the frame was cracked. It was no longer any good as a press but would have done many projects such as yours. *&^%#%^&**expletives!

I took no sarcasm from your post so not to worry. I was just wondering if you thought of something that would make this even simpler than it already is. I think I will stick with cast, after reading all the input here.

I hear you about throwing stuff out. My soon to be son in law, took over a leased space from a welding outfit that went out of business. The space was full of steel sheets, bar stock, round stock, angles, channel, etc. He had no use for it and took it all to the scrap yard . He had to use a fork lift and took several loads there. That was before I knew him. Now I have to go to the scrap yard and hunt around for useful pieces and pay them $0.40 to $0.50/ lb for scrap steel, $2 /lb for aluminum and $4 /lb for brass. He probably got $0.02 for the steel he took there.

Mr. Hall is a member here, and should be able to clarify any concerns you have regarding his design intent or reason for making this component from a certain material.

Good to know. I'm a fan of his. I don't want to bother him over something so trivial as I'm sure he is a very busy man. Since finding his website I have been enthralled with it and all of the information he openly shares. I now have 8 of his books and I doubt that will be the last of them in my library.

 

[Rustrp]

I was thinking about your source for cast iron, and thought about my sources for cast iron, which lead me to looking at a source close(er) to you. Maybe they have an item, blem, reject that's inexpensive......or they may be able to refer you to a better source.

http://www.reliance-foundry.com/

 

[HBilly1022]

I was thinking about your source for cast iron, and thought about my sources for cast iron, which lead me to looking at a source close(er) to you. Maybe they have an item, blem, reject that's inexpensive......or they may be able to refer you to a better source.

http://www.reliance-foundry.com/

That's very considerate of you and thanks.

I think I will try the machine shop in the closest city first, since I could use some other materials too. Like 12L14 for most of the project items. I've never used it but read that it is easy to machine and gives a nice finish. I use scrap that has been stored outside, is rusty and has to be cut from my limited supply of bigger stock. Then machined to size before I even begin to make parts. My large flat stock consists of 2 sizes: 1) some 1 1/2" thick by 10" wide plate and 2) some 1" x 8" wide plate. I cut this stuff close to size then trim again on the bandsaw and then square and reduce to size on the mill. It usually takes several hours to get to the starting block size. It would be much easier and faster to just have the right size stock to start with and maybe I should give that a try for once.

 

[Glenn Brooks]

A big +1 for using dissimilar metals for bearing surfaces. Steel on steel bearings will certainly gall, if shop made, unless one is hardened and possible ground smooth (thinking steel bearings and races here). Now an alternative is to make or buy a bronze bushing inplace of the cast iron. Not sure what your design is, but pre made oil,impregnated bronze bushes are cheap and plentiful in many sizes.

Another source for round bronze is go ask at marine repair shops- if you live near the ocean. Old bronze propeller shafts are always being replaced with new "and improved stainless steel" . An atrocity to be sure, but that does leave these shops often with old bronze shafts, which they might give to you if you explain who you are. I have scored an amazing collection of bronze shafting in this way, although had to pay salvage one time for 4" diameter yellow brass shaft that came off an old tug boat.

Good luck!

Glenn

 

[HBilly1022]

A big +1 for using dissimilar metals for bearing surfaces. Steel on steel bearings will certainly gall, if shop made, unless one is hardened and possible ground smooth (thinking steel bearings and races here). Now an alternative is to make or buy a bronze bushing inplace of the cast iron. Not sure what your design is, but pre made oil,impregnated bronze bushes are cheap and plentiful in many sizes.

Another source for round bronze is go ask at marine repair shops- if you live near the ocean. Old bronze propeller shafts are always being replaced with new "and improved stainless steel" . An atrocity to be sure, but that does leave these shops often with old bronze shafts, which they might give to you if you explain who you are. I have scored an amazing collection of bronze shafting in this way, although had to pay salvage one time for 4" diameter yellow brass shaft that came off an old tug boat.

Good luck!

Glenn

Great suggestions! Too bad I don't live close to the ocean. In the past that would not have been a problem, since the wife and I have been going ocean fishing every year for the last 26 years. I could have easily gone to one of the shipyards where we go and got some bronze or brass. Unfortunately she had a stroke recently and is slowly recovering but not able to be on a boat, so we had to cancel our 27th year. Maybe next year. I may check out the local supply place for bronze bushings but would prefer to make something myself, sticking with the I made it scheme.

 

[rgray]

When I built the Harold Hall dividing head I used the cast iron from a worn out chevy v8 crankshaft.
There is plenty of material in the counterweights on one of those.
It definitely takes more time to do vs nice round stock but is very do able.
An old engine block crankshaft main cap has come in handy a time or to also.

 

[HBilly1022]

When I built the Harold Hall dividing head I used the cast iron from a worn out chevy v8 crankshaft.
There is plenty of material in the counterweights on one of those.
It definitely takes more time to do vs nice round stock but is very do able.
An old engine block crankshaft main cap has come in handy a time or to also.

Another great idea! I picked up a couple of brake rotors from the local tire shop and I think they are cast iron but the material doesn't appear to be thick enough for the bearings so I will leave those for some future project. Next time I'm in the big city I'll hit up one of the machine shops to see if I can get a crank. I didn't know they were made of cast.

 

[Tony Wells]

All of them are not. Some are steel forgings.