The Armour Archive

First I would like to appologize because I know this topic has come up in the past, but it's one of those things "If you don't need it, You don't read it".

OK... I'm to the point where I want to clean up and polish a Sugarloaf Helm that I'm making. Since this is the first time doing a project that needs these steps, I'm not quite sure what equipment I should be using.

So with that said what tools do you use for sanding and what do you use for buffing metal. If I'm going to be buying new equipment, I want to make sure I get something that is going to last.

I've been looking at sander/buffers... Are they worth the money or are they just a glorified car buffer that you can put a sanding pad onto? The other thing I've been thinking about is a Baldor Buffer. It's a little spendy, but is it the worth it? or is there a better alternative that I might want to look into?

Thanks in advance for your help,
Sigeric

The first question is, what type of finish do you want? If you want a mirror finish, read on below. If you want a satin one, there are a million different options, others will give better advice than I.

For a mirror finish, first, make sure it's very well planished. And deep tool marks should be planished out rahter than sanded.

Next, you want to sand with a variety of sandpapers. I'd reccomend 100, 220, 280, 320, 400, and 600 grit, in that order.

For the 100 grit your best bet is a belt sander - prefferably a 2" wide, knifemaker's style, where you can work on a contact wheel, a platen, and free, as this gives you a variety of surface to work with. I'd advise against using a woodworker's 4" or 6" wide belt, as those tend to only have the flat patten to work against, and therefore will create flatspots. Another option is an expanding wheel or a soft-backed sanding pad. The nice thing about the latter 2 is that you can put them on your buffer, reducing the number of machines you'll need.

For the rest of the grits, you can hand sand, that's what I used to do. Recently though, I've been using a 1/4-pad orbital sander (the Porter-Cable brand is the best I've ever used), and am very happy with the results, except for the final 600 grit, which must be done by hand. The 600 grit pass must be done wet (soapy water works well), and with the orbital sander I've been wetsanding all of the grits, using alcohol as the liquid (less likely to damage the electric sander).

Once you are done sanding, you need to buff. For this, you'll need a buffing motor - any motor will do, but the Baldor buffers are much nicer. You should use either a loose or spirlal sewn buffing wheel, with green compound for steel and stainless, and red for brass. Make sure you never mix the compunds on the wheels, and never reverse a wheel once it's in use - I label mine with an arrow to show direction of travel.

After buffing with the rouges, take a paper towel, and rub the helm untill a clean paper towel comes away with no black on it. If you are working with stianless, you can wash it with soap and water, too. This is a critical step - the abrasives in the compound are all oxides, and if you leave any on the helm, they will induce rust, even on stainless.

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Yehuda ben Moshe
mka Juliean Galak
http://gerfalcon.tzo.com/medieval/armor/

Yehuda, thanks for the advise. Being able to do a mirror finish is my ultimate goal and if I am able to consolidate equipment... even better.

>>For the 100 grit your best bet is a belt sander - prefferably a 2" wide, knifemaker's style, where you can work on a contact wheel, a platen, and free, as this gives you a variety of surface to work with.<<

Can you direct me to a company that carries that type of sander... I'd like to see what it looks like.

Since orbital sanders do not spin, do you end up with some funky circular patterns? or will they just disappear as you go with the finer grits.

I like the idea of using expanding wheel on a motor or buffer. Does the motor speed make a difference. If so, what horsepower motor seems to work best.

Sigeric

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR><font face="Verdana, Arial" size="2">Originally posted by Sigeric:
<B>>>For the 100 grit your best bet is a belt sander - prefferably a 2" wide, knifemaker's style, where you can work on a contact wheel, a platen, and free, as this gives you a variety of surface to work with.<<

Can you direct me to a company that carries that type of sander... I'd like to see what it looks like.
</B></font><HR></BLOCKQUOTE>

Unfortunately, they are expensive. One of the best (according to people I've spoken to) is Burr-King, available at: http://www.burrking.com/

Some more basic ones can be bought here:
http://www.kovalknives.com/grinders.htm
Still pricy, and I have no idea on the quality..

A better option may be to make one yourself. The only hard-to-get part is the contact wheel and idler pulley, but you can get them from places like http://www.beaumontmetalworks.com

There's a knifemaking book, "$50 Knife Shop" by Wayne Goddard, that has a lot of info on how to build one.

Finally, Grizzly makes an inexxpensive combo buffer and belt sander, but I don't know what the reputation on that is like - Grizzly is not a great company, but it's cheap. Look here:
http://www.grizzly.com/products/item.cfm?Product_ID=12102&&User_ID=1725675&St=3602&St2=72571169&St3=-89515600&DS_ID=1


<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR><font face="Verdana, Arial" size="2"><B>
Since orbital sanders do not spin, do you end up with some funky circular patterns? or will they just disappear as you go with the finer grits.
</B></font><HR></BLOCKQUOTE>
You want to use a random orbit sander, and learn to use one properly. The trick to avoid weird swirlies is to always turn the sander on and off when it's not touching the workpiece, and to apply even pressure throughout. I have yet to perfect this technique, so I find myself frequently resanding swirlies...
<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:</font><HR><font face="Verdana, Arial" size="2"><B>
I like the idea of using expanding wheel on a motor or buffer. Does the motor speed make a difference. If so, what horsepower motor seems to work best.
</B></font><HR></BLOCKQUOTE>

Unlike most people here, I like low-power motors for buffing. IMHO, a 1/3hp, 1725rpm motor is ideal. This will also nicely drive an expanding wheel (the one I have is rated for 2500rpm, so the more common 3250rpm buffers can't run it). If you use my method, 1/3hp is plenty. If, as others do, you use more aggressive compounds instead of sanding, you may need more power - I don't know.

One idea a friend of mine had that he hasn't tried yet is to use an expanding wheels as a contact wheel for a belt sander (it's half the price of a commercially available contact wheerl). If he ever does so, I'll post a report here.

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Yehuda ben Moshe
mka Juliean Galak
http://gerfalcon.tzo.com/medieval/armor/

There are all kinds of ways to get where your going but the steps outlined above are a good place to start.

as far as belt sanders go I have one by N.E. Coote, who's web site shouldn't be hard to find. He sells them sans motor so you can shop around for the h/p RPM you want either new or used and save money there too. My 2x72 model with 10" contact wheel cost me around $410 with shipping and I run it with a 2hp leeson motor which, if I remember right, cost around $225. You might not need as beefy a motor so you could set yourself up with a serious sander for under $700 bucks.

I'd recomend getting the baldor motor if you can afford it. They outperform every other buffing motor I've used and last a long time.If you go for the baldor and your not armouring full time 1/2 hp should be more than adequate.

OK... I've now looked at the sites listed (and a few others), checked out a few knifemaking forums and read several reviews on each of the grinders. I've decided to go with the Grizzly, partically do to price, partically because it has a buffing arbor with it and partically because of the amount of time I will be using it. If I was a production armorer, I would definately go with something a little more heavy duty.

Now that I've selected a grinder/buffer, I need to pick up some buffing wheels. I've read through the 'Caswell Inc. - Intro to Buffing & Polishing' review, so I basically understand the difference between compounds and buffing wheels, but the one thing they didn't cover good enough was the wheel size.

My questions is... What is the optimal buffing wheel size 6", 8", other? or does it depend on what step you are taking. (ex. black compound, use a 6" wheel, final buffing use a 8" wheel). By the way the buffing motor is 1hp, 1725 rpm.

Any thoughts, Ideas, comments??

Sigeric

I personally prefer large diameter wheels, especially if the buffer has realativly short shafts. Larger dia wheels will allow you to work on odd shaped parts without the body of the buffer interfering with your work. They also allow you to run longer without recharging the wheel with compound.
I use the size wheel regardless of compound/abrasive type.

I would also recomend using the greatest face width of wheel your buffer will support. I generally stack wheels to get at least 11/4" face width.