Circle Shear Questions - Old Niagara

[CCWKen]

I've got an old Niagara R740 (From the 1920's) I'm trying to clean up and get working. The radius clamp is slightly off-set (forward of the die centers if you're right handed) but there's index marks for this position. When trying to cut a circle, the scrap side wants to bunch up behind the lower die.

1. Should the radius/center clamp be in-line with the dies' center line? Are the index marks original?

2. Duh. I wonder if that's what the guide does? I just realized that what I thought was just a straight line guide (L-shape) might be there to keep the scrap side up--to feed out. Yes, no? Is there something missing on the guide? (It wouldn't work well on rough cuts.)

3. There's a through-hole and set screw on the upper arm of the clamp frame and just behind and down from the center plunger. What is this for? Some accessory?

4. There's also about 1" hole at the back of the cutter frame above the top gear. What is this for?

Thanks for any info.

[Doug98105]

I've got an old Niagara R740 (From the 1920's) I'm trying to clean up and get working. The radius clamp is slightly off-set (forward of the die centers if you're right handed) but there's index marks for this position. When trying to cut a circle, the scrap side wants to bunch up behind the lower die.

1. Should the radius/center clamp be in-line with the dies' center line? Are the index marks original?

2. Duh. I wonder if that's what the guide does? I just realized that what I thought was just a straight line guide (L-shape) might be there to keep the scrap side up--to feed out. Yes, no? Is there something missing on the guide? (It wouldn't work well on rough cuts.)

3. There's a through-hole and set screw on the upper arm of the clamp frame and just behind and down from the center plunger. What is this for? Some accessory?

4. There's also about 1" hole at the back of the cutter frame above the top gear. What is this for?

Thanks for any info.


The only question I can answer is #1. Yes, the clamp should be offset, can't remember which way though. Or whether the offset is greater or less for large or small circles. My 18ga Pexto circle shear also has index marks for offsetting.

The same is true when shearing on a Pullmax with the circle cutting attachment. On my P3 P'max if the offset isn't correct the stock won't feed easily, adjust it correctly and the machine goes through 1/8" like butter.

I don't have enough experience with circle shears to know if the offset is as critcial as on the P'max.

Pictures????

Doug

[Jay Hayes]

Ken,

I have an old Niagara circle shear too. The clamp is on the center line of the shear blades, but can be off set for the best cut. The index marks are original. The numbers indicate the diameter of the circle. The guide behind the shear blades is used to cut straight cuts like a slitter. The through-holes with set screws on the upper arm of the clamp frame on mine holds a rod that a support bracket rides on. The support bracket supports the outboard side of the scrap and is able to be positioned to suit the size of the part. I'll have to have a look at the one inch hole. It doesn't ring a bell.

Jay

[CCWKen]

Thanks guys!

Here's a few pictures:

This picture shows the off-set[/b
http://img.photobucket.com/albums/0903/CCWKen/Tools/Circle%20Shear/Niagara-06.jpg

[b]This picture shows the index marks. (Clamp frame base--Not cutter bed)
http://img.photobucket.com/albums/0903/CCWKen/Tools/Circle%20Shear/Niagara-05.jpg

This is the 5/16 (accessory?) hole.
http://img.photobucket.com/albums/0903/CCWKen/Tools/Circle%20Shear/Niagara-01.jpg

This is the ~1" hole above the gear.
http://img.photobucket.com/albums/0903/CCWKen/Tools/Circle%20Shear/Niagara-03.jpg

[CCWKen]

Oh yeah, one more question. What color were these originally? The glossy "orange patina" just doesn't look right. :D I had it soaking in diesel for about an hour. Everything moves and I can turn all the nuts/bolts and adjustments. It just looks like it came from the bottom of a river. ;)

[geoking]

For reference : http://www.bcn-usa.com/ for all your machine needs.

They are expensive but a God send for your older equipment . Bliss Clearing Niagara maintains original documentation, operational directions and will build any missing parts for your machine to original factory specifications.

I bought a replacement bent shaft , replacement cutters and drawing/ set up directions from them.

I was lucky to find them and my machine is like new! smile

Hope this helps?
Regards,
George

[Homemade44]

Ken, my guess on the big hole above the gears is for another shaft and small gear to give some gear reduction when cutting.

Joe Hartson

[slobitz18222]

My cifcle cutter is set up dead nuts. The diamiter is the only adjustable part

http://www.metalmeet.com/photopost/data/3407/70waugh.jpg

[CCWKen]

Thanks Stan. I see you're another user/collector of fine old tools. :D

I plan to put this one back to work.

[Boogiemanz1]

I think you meant to say "a fine old collector of used tools!" :grin: :grin: :grin: ..........Stan's the man!..............john