Author Topic: cutting saw (Read 2571 times)

bullet maker · « **on:** February 15, 2003, 05:20:26 AM »

Quote from: Donna

Yes, the cutting saw from Dave Corbin is really nice and well built too.
http://www.corbins.com/prsaw1.htm

Richard Corbin has a copper tubing cutter saw too. But it looks like a converted miter saw. http://www.rceco.com/Images/Imagetube%20cutter.jpg

The teeth on Dave's saw are real tinny and it is for cutting aluminum and copper. The clamp holds a 5 ft long section a copper tubing unsupported, except at the cutting end securely, with out crushing it, as you can see from the pics. Although I am using .035 inch thick wall tubing, its quite strong. Hi Donna, I to have a cutting saw from Dave, and It works fine, except the blade does not last as long as it should. I use 1/2 inch copper tubeing to make my 444 bullets, and the blade lasted for about one 20ft tube and then the blade got so dull I just could not use it. I then tried the disck cut off wheel, it works but very smeared cutting where I then had to debur, both inside and outside of each cut off piece. I still experimenting with some other blade`s that I`ve got ordered from some machine works to see how they work.
Even with the orginaly blade I got with my saw, I still had to do some inside deburring.It is possible that the blade is turning to fast, 10,000 RPM I don`t know. Let me know if you have the same problem.
Does anybody else have the problem, and if so how did you solve it.
bullet maker

Donna

talon · « **Reply #1 on:** February 15, 2003, 07:42:01 AM »

I use a band saw made primarilly for wood cutting with a 14 tpi metal cutting blade. (I think the blade is 82" long). Made a very simple tube hold-down and measuring jig for it using the angle miter as a base. Have cut thousands of tube bullet jacket billets with the same blade. Can cut about 6 billets per minute to exact length. I think that you cut brass at a slow speed to keep the blade from over heating and then failing. A 82" blade runs cooler than a circle blade of 3"d even at the same speed, but I think that bandsaw runs slow as it is.

bullet maker · « **Reply #2 on:** February 15, 2003, 07:51:51 AM »

Hi Talon;
Can you send a picture of your set up? I can`t visulize how it would work., But if I seen the picture, I`d get a better idea. I`m stuck with this Corbin set up, to expensive to give it up, so I`m trying to make a better one out of it.
How is the jackets when you cut them? do they need any deburring inside, outside?
Thanks, bullet maker

talon · « **Reply #3 on:** February 15, 2003, 09:44:06 AM »

Bullet Maker, I'm alway from my home (and swaging bench) during the winter, but will be back in 2 months. Can send a picture then. Actually, the jig is VERY simple: the only thing you have to protect against is not applying any feed pressure ( as differentiated from hold down pressure) on the tube once the cut starts, and to keep the freahly cut billet from rolling against the blade. The roughly and quickly made jig works so well that I plan to redo it as soon as I get back (I have both the 3/8th and 1/2" jacket maker kits.) If a person has, or has access to, a band saw to start with it's a very low cost method of doing the job! As far as triming the billet ends just before slipping them on the end-rounder punch, one end (both inner and outer wall) is easilly trimed, in 2 seconds, using a shell case beveling tool). The other end, as Mr Corbin states, is cut well enough to leave alone. And, I've mentioned before, as I don't have one of Mr Corbin's adjustable end rounder punches, I've acquired a bunch of hardened steel rings of the same diameter and thichness of the tubing to allow me to roundover various lengths of copper tube billets. Lastly, since I met Butch Hairfield two years ago and his extensive and very economic selection of jackets, I haven't had the need to make my own any longer.

bullet maker · « **Reply #4 on:** February 15, 2003, 09:56:34 AM »

OK< thanks talon, when you get b ack I would like to see your sit-up. I know of mr Hatfield, and he does a wonderful job, but I like to do things, myself, every penney I can safe, is a penney earned. Or more I can spend on my hobby.
Thanks
bullet maker

Donna · « **Reply #5 on:** February 17, 2003, 10:47:21 PM »

Bullet maker,

I’m sure your right about that saw blade turning too fast. It seems to me its turning at lease three or four times too fast for me. I think I'll see what I can do to cut the speed down on it.

Donna

Cat Whisperer · « **Reply #6 on:** February 18, 2003, 01:20:21 AM »

Now we're talking about speeds and feeds. The speed of the tooth should be matched to the material being cut. Adjusting the feed is done by hand so just watch whether or not it loads up or cuts cleanly.

For the rate of speed - look in Machinery's Handbook (or similar references) for the type of material and there will be a listing for the velocity of the tooth - which is easily converted to RPM.

To adjust the RPM it is a simple matter to use an autoformer like a Variac to slightly increase or widely decrease the voltage going to the motor. Electronic speed controllers are also commonly available.

bullet maker · « **Reply #7 on:** February 18, 2003, 01:06:45 PM »

Thanks Cat Whisperer, for the advice, sounds good I will check it out.
It`s just aggravating that one would spend a lot of money for a product that should already be worthy to begin with. Of course I am referring to Corbin`s saw.
Thank`s bullet maker

Cat Whisperer · « **Reply #8 on:** February 19, 2003, 11:57:12 AM »

Just a few thoughts on speeds and feeds. The speed through a particular material is given for different types of cutting (lathe, drill, milling etc.).

The tables are guidelines from which one deviates because of experience.

ALL of these list the speeds for cutting copper to be somewhere between 80 and 120 feet per minute (speed of each cutting tooth through the material).

A speed of 100 feet per minute is 1200 inches per minute. The circumference of a 3" wheel is about 9.42" which at 10,000 rpm (really?) is 94,248 inches per minute.

A faster speed will allow a shallower cut and a finer finish, but also means higher heat and shorter tool life.

Slowing down the motor will help SOME. But getting it down to 500 rpm still gives 4,712 feet per minute - still a bit (theoretically) high.

bullet maker · « **Reply #9 on:** February 19, 2003, 12:10:14 PM »

Hello Cat Whisperer
I think my best bet would be to get a speed controller. Do you know of a web-site that has the controllers?
Thanks
bullet maker

dead_eye · « **Reply #10 on:** February 19, 2003, 03:53:01 PM »

Hi,
To help out, a speed control you can use is one that I use on my router.
It works great and it won't break you. $24.99 :eek: It is at:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=43060

Also a idea on a tubing saw can be found on the same site, it a mini cut-off
saw with 2" HSS blade. These blade is like slit saw used on milling machine. The speed of the machine is 8700 RPMs. Price!!! $29.99 :eek:
Price of 3 new blades $9.99 :eek:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42307

The best is the shipping, spend $50.... it FREE!!! :eek:
I hope this helps......

dead_eye · « **Reply #11 on:** February 19, 2003, 04:03:32 PM »

I got to looking, they also have a cheaper one, but I can only comment
on the other as it the one I have. Price: $19.99 :eek:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=43584

These work with any universal AC/DC brush type motor, 15 amp and under. (Won't work with soft- or slow-start motors.) Keep this in mind
when your buying them... :mrgreen:

bullet maker · « **Reply #12 on:** February 19, 2003, 05:14:27 PM »

Quote from: dead_eye

Hi,
To help out, a speed control you can use is one that I use on my router.
It works great and it won't break you. $24.99 :eek: It is at:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=43060

Also a idea on a tubing saw can be found on the same site, it a mini cut-off
saw with 2" HSS blade. These blade is like slit saw used on milling machine. The speed of the machine is 8700 RPMs. Price!!! $29.99 :eek:
Price of 3 new blades $9.99 :eek:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=42307

The best is the shipping, spend $50.... it FREE!!! :eek: O.K. thanks alot dead eye, I whished I had known about them a year ago. Thanks for the site.
bullet maker
I hope this helps......

bullet maker · « **Reply #13 on:** February 19, 2003, 05:38:57 PM »

Hey dead-eye,
Thanks for the information, I went to the site and saw what you were talking about. :roll: If I had known about this place a year ago, I could have saved myself 400.00 :oops:
I`m sure glad you posted me, I did find a HarborFreight store, about 54 miles from me. I never knew they were around these parts.
Again thanks alot. By the way, got anymore savings you can pass along.?
bullet maker

Donna · « **Reply #14 on:** February 19, 2003, 11:58:06 PM »

Hello all,

CW – a 3” wheel spinning at 500-RPM gives you 4,710 inches per minute not feet, it is 392.5 feet per minute. Just to set the record straight.

I’m going to get a nice Variac from minute-man.com at: http://www.minute-man.com Variable 500 VA Transformer Model AEEC590 for $50.00. I heard that HarborFreight sales stuff that no one else will sale, just what I heard.

But I sure that Dave Corbin’s saw is fine, I know it is well built and of mostly metal construction, it just turns too fast but a good variac is all that is needed. This one is Output: 0-130VAC @ 20 Amps, plenty more than is needed; this also has an output meter so you can insure the same speed. No, I know it is in volts not RPM but volt can be related to RPM’s very easily. I also found 3” saw blades for Dave’s saw through “KBC Tools & Machinery” for around $5.50 each.

And I’ll let you know how the blades workout with the variac.

Donna

Cat Whisperer · « **Reply #15 on:** February 20, 2003, 12:48:42 AM »

Donna -
Thanks for the correction. I always did get feet and inches confused.

The motor controller and the variac operate differently and may give different results.

The variac will scale down the sine wave of the applied voltage and current.

The motor controller uses something in the SCR (silicon controlled rectifier) family of 4 layer devices and will turn each half cycle on and off so you get a wider or narrower slice of the half cycle at full voltage and current.

With both you will get the motor running slower and slower until at some point it wont run. It's easy to cut it back to MAYBE half but past that it's up for grabs. The design of the motor (how it's wound) will make a big difference. It is likely that it may be gotten to RUN at slower speeds but it won't have much power at all.

Another approach would be to cool the blade. A mist of water will do it as will moving air. Both would help with chip removal (another cause of heating the blade).

Good luck and keep us posted.

dead_eye · « **Reply #16 on:** February 20, 2003, 08:09:19 AM »

Hi again...

Donna,
No disrespect but I have bought a lot from harbor freight and have not been disappointed. What might you have heard is more so that they have new products that you have not seen around. I think its great for them to do so. Most company are chicken on buying new products do to the economy. It has been so cold I havn't used speed control for a while but if I remember right, the speed control adjust with the load to maintain the same speed. I will have try going to the garage and dig into some oak with the router to see if that true.

Bullet Maker,
Great deal... I am full of them..that why my eyes are brown :-D :-D :-D
Give me a problem and try helping out...
kidding aside... I have read into swagging but have just reloaded. That why you will have to give me some problems. I have also looked at swagging site on the forum for more info also.
The calibers I have are: .223, .243, .257, .308, .311 rifles
contender pistols in .223, .357, .430, .452, .458

Can you help answer a few question?

Why bullet swag?
Is it cost effective?
Is it just for odd ball calibers?
how much equipment is envolved?
any other info would help make my decision on getting into swagging.

Thanks everyone!
well I better scooting along :bye:

Cat Whisperer · « **Reply #17 on:** February 20, 2003, 12:41:14 PM »

If it is common (it appears to be so) that the tubing cutoff saws are generally very high speed, then it follows that people in general are having some significant success with them.

It also follows that since the remaining variable (other than speed and the material being cut) is the BLADE that there must be some blades that do better than others, i.e.: that the design of the blade (shape of teeth, cooling, material, hardness, grind, side clearance and so forth) is crucial.

Just something to think about.

Leftoverdj · « **Reply #18 on:** February 25, 2003, 03:53:49 AM »

Are you folks using a cutting lube of any kind? The common one for brass is kerosene. I'd sure try touching the side of the blade, close as I could get to the teeth, with a Q-tip loaded with kerosene.

Matter of fact, I'm going to, just as soon as Harbour Freight can get me one of those cute little saws. Thanks for turning that one up.

I'm not a swager, but I have shortened a few thousand cases over the years. Looks like exactly the same problem to me. Did the first few hundred on a lathe and then built a gizzie to use in a drill press. Gizzie was just a mandrel to go in case neck and a pivoting cutter arm. Mandrel had a shoulder on it and screwed up and down in the base to give a little length adjustment.

I played with drill press speed until I found one that gave me a continuous ribbon of cutting. That single tooth cut and lasted well, lubed with kero. Biggest problem was that cases with uneven wall thickness tore on cutoff.

talon · « **Reply #19 on:** February 25, 2003, 06:01:50 AM »

Dead Eye, concerning your 20 Feb posting::: go to www.corbins.com Then click on "FREE INFO" on the lefthand sidebar. Then click on "E-BOOKS" on the left hand sidebar. Then down load HB-8.... The Corbin Handbook, 8th revised edition should answer all your questions. In the bullet swaging field there is NO OTHER contempory writting that covers so much. For myself, I swage because it's extreemly interesting and, from time to time, provides me with a few bullets I can use. (for instance, I make jacketed bullets in all the calibers you cited except for the 44-40 (.430) and for that I can only make lead ones).

Lead pot · « **Reply #20 on:** March 08, 2003, 10:10:46 AM »

Dona.
Go to "grizzly.com" It's a tool site and look under
"HSS SLITTING SAWS"
Those are high speed hollow ground low friction glades made for this kind of material and cuttind screw slots.They come in various sizes and teeth per inch,up to 48 per inch.Lp.

BUTCH HAIRFIELD · « **Reply #21 on:** March 09, 2003, 08:20:28 AM »

you can get your blades alot cheeper from victory supply than from dave. the saw is a good saw but a bit slow and has a tendancy to get hot.
http://www.victornet.com/cgi-bin/victor/index.html

butch

TomF · « **Reply #22 on:** March 16, 2003, 12:18:49 PM »

Speaking of Corbin Mfg's saw....the spec says: "115 volts, with a 10,000 rpm 1/5-HP motor".

Is that REALLY 10,000 rpm from a 1/5-HP motor? Or, is it 1,000 rpm, which would seem more reasonable?

I, too, was looking for a cheaper solution, but have not found a motor with those specs!

BUTCH HAIRFIELD · « **Reply #23 on:** March 16, 2003, 12:51:53 PM »

IF YOU NOTICED IN THE PICTURE THERE IS A BELT AND A SET OF PULLIES AND THIS WILL REDUCE THE RPM OF THE MOTOR THAT THE CUTTING BLADE IS RUNNING AT.
THERE ARE ALL KINDS OF MOTORS THAT RUN AT 10K PLUS RPM UNLOADED AC AND DC. THEY RANGE FROM ABOUT 50 DOLLARS AND UP. I PURCHASED A DC 7000 RPM RECENTLY FOR ABOUT 25 DOLLARS FROM SURPLUS SUPPLY.

THE BIG TRICK TO BUILDING YOUR OWN IS SOME HOW BEING ABLE TO MOVE THE PART ACROSS THE BLADE OR THE BLADE ACROSS THE PART. IF YOU MOUNT IT DIRECTLY TO THE MOTOR THEN THE PROBLEM GETS WORSE ( THE MOTOR WILL GET IN THE WAY). THEN IF YOU MOUNT IT ON A ARBOR LIKE DAVE DID THEN YOU HAVE TO FIND A SET OF BEARINGS THAT WILL TAKE THE SPEED AND SOME WAY TO MOUNT IT. THERE ARE SOME CHOP SAWS ON HARBOR FREIGHT THAT WILL WORK BUT I HAVE MY DOUGHTS ABOUT THEM AFTER SEEING THEM IN A STORE. I DO NOT THINK THEY WILL HOLD UP. NOW THE SMALL TABLE SAW ONE HAS SOME POSSIBILITIES AFTER MODIFING IT SO TAKE YOUR CHANCES.

I HAVE THOUGHT ABOUT OFFERING A CUTTING SERVICE FROM MY BUSINESS WHERE I GO IN AND CUT AND CHAMFER THE TUBING FOR YOU AND SEND THE PEACES BACK TO YOU. BUT I CAN NOT KEEP UP WITH WHAT I HAVE GOING ON NOW LITTLE LESS ADD SOMETHING LIKE THIS TO IT.

YOU KNOW IF YOU TOOK ONE OF THE SMALL HAND HELD PANEL SAWS AND TURNED IT UPSIDE DOWN AND MADE IT INTO A TABLE SAW AND MADE A JIG TO SLIDE BACK AND FORTH OVER IT TO HOLD THE TUBING THAT MIGHT WORK ALSO. JUST A THOUGHT

REMEMBER THE BOX IS ONLY THE STARTING POINT

BUTCH

Donna · « **Reply #24 on:** August 01, 2003, 12:09:21 AM »

Hello all,

I finely ordered a variac two days ago for my copper tubing saw by Dave Corbin and it arrived today, fast service. The variac is a 117-volt input and from 0-130 volt output at 5 amps, from Action Electronics for $90.00 model number SC-5M, it’s real nice and a pretty red to match the saw. I could have gotten a less expensive variac but I would rather pay a little more once than buy another one later, it is less expensive in the long run this way.

With the variac set to about half way up the scale, the saw cuts slower but the blade does not get hot and I can now touch the cut off piece of tubing right after it is cut off where as before there was no way you wanted to touch it for about 5 minutes. The saw blade should last for a good while now. I use a caliper to set the length that the saw cuts and making sure the tubing is square I tighten the hold down clamp. As I bring the blade down to cut I ensure that the blade always cuts on the same side of the slights lack in the linkage due to tolerances even though the cut off set from side to side is only about .008 total distance. I started out using a Cnamfering-Deburring Tool to make sure the edges are clean for reliable length-to-length cuts but I soon learned that some fine steel wool works faster and better for this job. After I got a little practice I was cutting very consistent lengths were talking around ±0.005 inches or less.

Jackets made from ½” diameter by 0.035” wall copper tubing and drawn down to .451 caliber sure is massive, for a 300-grain bullet the jacket alone weighs 115-grains. It is defiantly a time consuming activity but it is also a blast, no pun intended. This is going to be one H### of a bear getter.

Have fun.
Donna

Cat Whisperer · « **Reply #25 on:** August 01, 2003, 03:45:50 PM »

Donna -

Glad to hear the variac worked. Keep an eye on both the variac and teh motor temperatures if you do a lot of cutting. Rated at 5A the variac shouldn't heat up much at all, but running the motor slowly may cause more heat to build up.

I would assume that you have reduced but sufficient power at the lower speed.