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So one thing I don't get, why are bandsaws with cast iron wheels, trunnions, etc. more expensive than similar bandsaw with cast aluminum parts? Like grizzly puts aluminum wheels on cheaper bandsaws but uses cast iron for the more expensive ones. I thought aluminum was more expensive to manufacture than iron due to the amount of energy needed. Or was it mostly due to weight?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

When I bought my bandsaw they said the wheel could be cast iron or aluminum... seems kinda weird they do that. I was lucky it was cast iron. Only thing was the cast aluminum trunnion... I guess you can't have everything. What is it about cast aluminum that sucks so much? Is it due to the fact that they can be bent if tensioned too much?

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

Besides the weight iron is tougher and a bit more work to machine but the advantages far out weigh the costs , Less vibration and durability and longer wear life. Quality cost , and cheap is often more costly than qualtiy

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Iron as a raw material may be cheaper than some aluminums, though it's harder to work. To cast it you need higher temperatures, which costs money. Then after
Casting you have to machine the iron, which is more expensive. You wear out more saw blades, grinding belts, drills, end mills, and other cutting tools a lot more readily on iron than aluminum. For instance I could put a carbide insert in the large and cut the OD of bandsaw wheels all day, everyday, for a week and not have to change out the insert. On cast iron the insert will be changed numerous times in one day. Those inserts can cost anywhere from $15-$50 a piece, that has to be figured into the cost. Also with iron you have to cut more slowly which increases cost. There is a lot of things that drive the cost up and those are just a few.

I wouldn't say anything about cast aluminum "sucks". It's wonderful for certain jobs and not so great for others. As others have mentioned the iron is much heavier which makes for a more rigid set up. Also it wears much slower than aluminum, this however does not make aluminum suck. It just doesn't make it ideal for this specific purpose.

Tell the folks who have to machine the cast iron how much better it is compared to aluminum and see what they say.......!!

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A person who has never made a mistake has never made anything!!!

Actually one of the best bandsaws on the market has aluminum wheels. Northfield. T

I think Laguna has aluminum wheel too (correct me if I am wrong).

I was under the impression that in order to refine aluminum they have to dissolve bauxite into cryolite and run electric current through it, which costs money in both heat and electricity. Although I can understand the difficulty in machining cast iron compared to aluminum... I could even cut aluminum on a woodworking bandsaw if I go a bit slow. I can't cut anything approaching the hardness of iron on a woodworking bandsaw, even with bimetal blades without trashing the blade in short order. A nail just ruins a bandsaw blade instantly.

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Cat-gut strings are made from kitten guts, stretched out to near breaking point and then hardened with grue saliva. As a result these give a feeling of Pain and anguish whenever played, and often end up playing themselves backwards as part of satanic rituals.

Typhoon Guitars
http://www.typhoon-guitars.com

which is part of the reason why aluminum ingot costs more than iron. But that just gives you the ingot. In order to have a completed part a mold has to be made, whether made of sand, plaster, metal, etc depending on the type of casting taking place. Ten the ingot has to be melted and poured into the mold. Once the metal is cooled the part is removed and the gates and risers must be removed. Then off to machining. The cost of the ingot is just a fraction of the cost of a finished part.

Poorly made cast iron can sometimes be hard to machine due to hard spot but the unpleasant thing is the black that is released during machining. Gets over everything. Aluminum is much more pleasant to work.
Tom

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A person who has never made a mistake has never made anything!!!

To get the same strength of iron you need more volume in material of aluminum and there are many alloys. Some are not suitable for wheels. As a machinist Cast iron isn't that bad to work and aluminum is not without its issues. Aluminum needs to be machined with a coolant to avoid binding to the cutter.

_________________
John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it