Is cast iron always best?

[Mike.C]

Hi All,

Nigel, yes reject it straight away. No it is not what you should expect for the price.

When you buy goods from a trader such as a shop etc you enter in to a contract that it controlled by the Sale of Goods Act 1979 (amended by the sale and supply of goods act 1994) and the sale and supply of goods to the consumers regulations 2002). The law gives certain implied, or automatic, statutory rights, under this contract.
This act states that goods should be of satisfactory quality, ie of a standard that a reasonable person would consider to be satisfactory-generally free from fault or defect, as well as being fit for their usual purpose, of a reasonable appearance and finish, safe (which with the NVR switch faulty this is not) and durable.
As your saw is clearly not of reasonable quailty you have every right to reject it.
I do not know how long you have had it, but if i was you i would reject it right away, because in my experience the longer you wait the more likely they will try to palm you off with any excuse.

Good Luck

Mike.C

 

[johnelliott]

The above experience shows that cast iron is not automatically better than aluminium. Cast iron needs to be correctly treated after being cast and before being machined. Is this happening on any of the machines discussed above?
I would not consider cast iron for any of my machines because I do ocassionally need to move them, and the cast alloy tables on my Kity planer, and the extruded ally table on my EB table saw are plenty flat enough.
John

 

[Mike.C]

Hi All,

Philly the Jet 54A if i remember rightly. I have the Axminster version.
I get that reaction too. Pass a bit of hardwood over them 3 blades and their jaw drops when they see the finish.

As i have already said there are good non cast iron machines, but on some of them the fence lets them down. Call it the material used, the mechanism, or the design, in my experience you cannot get away from the fact that the fences leave a lot to be desired, and i am not talking about the £50 special's but machines from major companies.

Yet when it comes to cast iron machines you do not get any of that.

Adam, i have the TS2500 and i find your post very instresting, can we really get a cast iron table for the older Scheppach? Did they tell you how hard or easy it would be to retro fit it? i.e. would the saw have to go back to them, or could the owner fit it?
One thing i don't understand is how does this make it possible to fit a dado head cutter, surely you have to change the motor because the spindle/shaft is not long enough?

Regards

Mike.C

 

[Anonymous]

To say that it is not necessary because it is for home use or for small production runs is missing the point a bit. I do not see why, just because someone wants to do a hobby, or is a small manufacturer he must use inferior quality machinery.
John

John

Not sure if anyone has actually stated that entry or mid level machines with aluminium tables are inferior to cast iron tables. I am of the the firm opinion that they are not and I back this assertion up with the knoweldge gained from 25 years as a design engineer specialising in the design of bespoke machinery and an academic in a mechanical engineering department.

Sure, iron is heavier (damps vibration) and will move slightly less with changes in temperature BUT we are machining wood here, not metal and wood moves with changes in humidity and temp. far more than any inaccuracies in a half decent machine tool.

I believe that it is not about 'better' but personal preference and (particularly) users perception, i.e. big pro machines are cast iron ergo it is better to have cast iron.

My 12" sander has a cast iron table. Charnwood sold an aluminium one too but I chose iron on that occasion. It was the same machine and the iron one is no better - my choice to go for iron was purely a personal preference and nothing to do with the performance of either.

Cheers

Tony

 

[Midnight]

Tony.... I hate to do this.. but I own an entry level cast ally topped saw.... that is grossly inferior to just about anything on the market... Don't get me wrong, I'm not saying that ally can't be machined to tolerences every bit as fine as cast iron... but in this case, the manufacturers tolerences are in yards....
Only decent feature in the saw is the blade.... an that's an aftermarket addition....

 

[Alf]

Welcome to the forum, Nigel. The others are on the money there; take it back. BTW, congrats on being Norm-influenced but still seeing the wisdom in bandsaw ownership. :wink:

Now John (E) brings up an interesting point, and one familiar to me as a plane junkie. Cast iron has a delporable tendency to move. Are the castings on these cut price machines being allowed to season (or whatever they do these days) before they machine them? Are you at risk of starting with flat surfaces and then finding to your horror, and after you can reasonably return them, that they've warped? I don't know, but it's a worrying thought isn't it? On which comforting note, I'll leave you all to dash to your cast iron, straight edge in hand... :lol:

Cheers, Alf

 

[johnjin]

Hi Alf

Yup you are right.
Cast Iron castings do need to be weathered. A quite simple process of leaving the raw castings exposed to the elements for while. This is part of the quality control process. ( or should be ) After machining It will have less tendency to move than any other material. I was trying really to point out that professional machinery is made of cast iron for a reason. It is far more robust, will expand and contract far less, absorbs vibration far in excess of aluminium or steel. These reasons and others all seem to be reasons why the home woodworker might like it in their shop. The only downside for me with cast iron would be the weight, if you need to move it around. Aluminium tables tends to scratch, dent or distort very easily and although in an ideal world they would not have all manner of things piled on the table or dragged across them the facts in my case are far different. So once again I come back to saying I love Cast Iron.

All the best

John

 

[Chris Knight]

For those who have an inferior cast iron top and want to do something, here is a link that may be useful

http://www.tdl.com/~swensen/machines/flat/flat.html

 

[johnjin]

You've done it again Chris
Another fantastic link. God knows where you get them from.
But thanks very much.

all the best

John

 

[Adam]

Adam, i have the TS2500 and i find your post very instresting, can we really get a cast iron table for the older Scheppach? Did they tell you how hard or easy it would be to retro fit it? i.e. would the saw have to go back to them, or could the owner fit it?
One thing i don't understand is how does this make it possible to fit a dado head cutter, surely you have to change the motor because the spindle/shaft is not long enough?

Regards Mike.C

It seemed you could retro fit a cast iron top to either the TS2500, or the TS4010, should you wish so (not for me, I can't fault mine). On the TS4010 it already has a long arbour, so this would allow you to take the moulding head, or whatever you call it, on the TS2500, the arbour is still to short, so you couldn't do it without lots more expense. It's possible, but cheaper to probably sell the table, and buy it's new replacement.

Sorry, I don't think my post was very clear.

Adam

 

[Anonymous]

Nice link Chris


Cheers

Tony

 

[Anonymous]

One thing most people seem to forget about aluminium is that it's density is much less than cast iron, - it therefore needs much less weight of aluminium to build a table top, and these metals are sold by weight. An engine designer told me a few years ago that aluminium and cast iron are similar prices when looking at volume. I've never actually bothered to do the sums but it sounds quite reasonable to me. So a cast iron table could actually cost significantly more than an alloy table when higher energy input (for melting), machining and transport costs are taken into account.

 

[Chris Knight]

Tony,
I try!