# Cutting Centering rings

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#### Orbital

##### Well-Known Member
Didn't know if anyone has tried this..

I bought 2 circle cutters from Harbor Freight and simply put 2 more cutter heads on one tool.. I changed the blades around to cut properly.. I use my digital caliper to set the proper inside and outside diameters. I did grind the two outside blades down a little so that the center diameter would be cut through first keeping the ring stable until the outside diameter is cut and released. Go nice and slow.

Every ring turns out perfect..

#### Ryan S.

##### Well-Known Member
whoa that is pretty cool, that thing looks like a weapon.

Thanks Ryan..

#### el chubbo

##### Well-Known Member
So the center ring cuts out first and then the outside? I'm really impressed.....

#### edwardw

##### Well-Known Member
Do you have any problems after the centering ring drops out with the tool keeping the outside circle aligned?

#### sandman

##### Well-Known Member
I never thought of combining the parts from two circle cutters.

SLICK!!

My guess is that you have to clamp the part down really tight.

sandman

#### Ryan S.

##### Well-Known Member
I would think so too, that would add alot of torque

#### Orbital

##### Well-Known Member
Yeah I clamp it down real good and don't use much force when cutting.. The center scrap just starts spinning with the tool when it's cut.. Then when the outside cuts through the ring just spins with the tool.. It's pretty slick.

Here are a couple of rings I cut from 1/4 ply.. They fit in a 4" airframe with a 54mm motor tube.. Took all of about 1 minute each to cut.

#### Zippy

##### Well-Known Member
Does anyoner have the Harbor Freight part # for a circle cutter?
I can't find one at the online store even though I tried a bunch of different searchs.

#### eugenefl

##### Well-Known Member
TRF Supporter
Originally posted by Zippy
Does anyoner have the Harbor Freight part # for a circle cutter?
I can't find one at the online store even though I tried a bunch of different searchs.
<a href="http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=2383789343&category=11704">THESE</a> are on eBay ALL the time. Cheap too for only about $7! I also have a single blade Craftsman that set me back$19.

TRF Supporter

#### Zippy

##### Well-Known Member
Yea I buy at ebay once in awhile, only thing is I need a vernier caliper too and I haven't been able to match up a caliper with a cutter from the same dealer yet so I can save on shipping. I'll try again in a month or two since I don't really need them yet. I have a 3.5" shipping tube I might want to use (from the rail) and I'll have to make custom rings, but thats still a couple of projects down the road.

#### wwattles

##### Well-Known Member
I've only got the Craftsman single-blade cutter, and it's still hard to get to cut the perfect sized rings. How on earth do you do 4 of them at once, or even two that are even?

WW

#### Orbital

##### Well-Known Member
It does take a little time to set it up.. I cut some sample rings out of scrap to check the size..

Using a digital caliper really helps.

#### cls

##### Well-Known Member
that's a really great tip!!

I bought a LOC 54mm->38mm adapter kit and I really pondered for a long time, how did they cut so nicely those 2 little plywood rings. now I know.

TRF rocks!!!

#### kelltym88

##### Well-Known Member
Hey orbital,
If you would like some practice, I'm looking for 6 CR for a 2.6 dia. BT to hold a 29mm MMT. I am planning on converting my Optima and Shadow kits to 29mm and I don't really want use the stock CR's. Let me know, be glad to pay for them. Thanx.