Question for Experienced Monster Rig users

[Roger Chandler]

While hollowing the maple vase I posted, I had a good bit of chatter when I got around 10 inches deep............most of you have stated the same experience............

I was wondering if you thought it would allow a greater depth of hollowing if one used a rest that would go inside the opening of the form........see below:

http://i20.photobucket.com/albums/b239/woodchuck102/Boxpair2.jpg

193779

[Steve Schlumpf]

Roger - the one thing I do to cut down on chatter is to use a smaller sized cutting bit and take lighter cuts. Your idea of using a box tool rest may work - but remember when hollowing - all those shavings have to go somewhere and you may get a bottleneck real quick with something hanging inside the form. Don't know till you try it...

[David E Keller]

Although I haven't done it yet, I've been contemplating the same thing... Seems like anything that decreases the overhang would help with vibration. The only trouble with this solution is with smaller openings, but larger bars are an issue there as well. I still don't understand how Ellsworth gets 12 inches deep by hand through a 1/2" hole... I guess that's why he's a master, huh?

[Roger Chandler]

Roger - the one thing I do to cut down on chatter is to use a smaller sized cutting bit and take lighter cuts. Your idea of using a box tool rest may work - but remember when hollowing - all those shavings have to go somewhere and you may get a bottleneck real quick with something hanging inside the form. Don't know till you try it...

Steve.........I guess I posed that question before I thought the thing through.........you are so correct about the shavings backing up in the form.....it would only take seconds.............a pretty frustrating scenario on a deep vessel! :(

[David DeCristoforo]

No matter what tool you use, you are always better off with as little of the tool hanging over the rest as possible. But these look like flat steel bars and they are not going to be very rigid. Not unless there is a gusset on the bottom that does not show in the pics. Also, you will need to leave a substantially larger opening to accommodate the rest and the hollowing bar. So, unless I am missing something (who??? me??? gasp!!!), this is not going to help much. I have found that the "secret" to hollowing that deep is very sharp tooling and very light cuts. Of course, a fatter hollowing bar would not hurt either! But then, there is that opening size thing again...

[Roger Chandler]

Although I haven't done it yet, I've been contemplating the same thing... Seems like anything that decreases the overhang would help with vibration. The only trouble with this solution is with smaller openings, but larger bars are an issue there as well. I still don't understand how Ellsworth gets 12 inches deep by hand through a 1/2" hole... I guess that's why he's a master, huh?

David.............maybe the answer is a bigger diameter boring bar.........I wonder if Randy could do that for the articulating unit?

[Roger Chandler]

David D. ........I guess I was busy typing when you posted......you said pretty much the same thing about the larger diameter boring bar as I was thinking..........

A larger hole could be capped with another piece of wood made to fit............I guess it boils down to the amount of work one wants to put into a form in one way, or the other.

[David E Keller]

David.............maybe the answer is a bigger diameter boring bar.........I wonder if Randy could do that for the articulating unit?

Larger bar and smaller cutter tips... I think I've heard of Randy making larger bars for people before, but I could be mistaken.

[Bernie Weishapl]

I do the same as Steve does. I go to a smaller cutter and clean out chip more often. Cuts out a lot of the chatter.

[Jamie Donaldson]

I made several of my hollowing tools that fit into the 5/8" to 3/4" Monster step-up adapter that Randy makes for the Monster system, and the best one is a hardened steel half shaft from a fairway mower axle. Make sure that you are always cutting above center line, and as others have said, sharp cutters and small bites are necessary.

[James Combs]

David.............maybe the answer is a bigger diameter boring bar.........I wonder if Randy could do that for the articulating unit?


Larger bar and smaller cutter tips... I think I've heard of Randy making larger bars for people before, but I could be mistaken.

I think you guys are on the right track with the larger bar. I have replaced my mini monster 1/2" round bar with a six inch longer 1/2" SQUARE bar and it helped a bunch. Just having the extra metal that the square bar gives me allows deeper cutting with less vibration.

[patrick stein]

hi jamie,

with the monster system you should be above center?would that be the same if using monroe hollower in the monster rig?

thanks patrick

[Roger Chandler]

On my vase project, I got the best finishing cuts using this head

193804 note that it is the round carbide cutter in the 45 degree angled boring bar tip. Note the angle of the cutter head itself........maybe about 30 degrees downward.

And not with this one:

193805 this one is the tip that rotates, and I use it for the sides and under the lip for areas the straight bar has trouble reaching.

Also, I used the longest configuration on the boring bar setup.......extensions that brought the bar to an 18" length for the finish cuts. For the main hollowing I did not have the 6" extension installed. Below is the longest confiquration that I used in the finish to give me light cuts and plenty of reach:

193806 look how smooth the cutter left the finish 193807 I did a little pass of 80 grit here, but not much........the cut was pretty smooth off the round carbide cutter head, and the important thing is this.........with the downward angle, I had no "catch-y-ness" with it, although I was trying to use light passes and did so from bottom of the vase back out to the rim.

It was with the main hollowing that I had the chatter........after some more thought on it, there was a good deal of overhang, and when I vacuumed out the chips more frequently, it did help, so maybe that is a part of the correct technique......cleaning out the chips about every minute or so.

[James Combs]

On my vase project, I got the best finishing cuts using this head

193804 note that it is the round carbide cutter in the 45 degree angled head. Note the angle of the cutter head itself........maybe about 30 degrees downward...

... I did a little pass of 80 grit here, but not much........the cut was pretty smooth off the round carbide cutter head, and the important thing is this.........with the downward angle, I had no "catch-y-ness" with it, although I was trying to use light passes and did so from bottom of the vase back out to the rim.

I would really be interested in more details on your technique for using the carbide cutter. So far I have had very little success using it. For me it grabs like the most tenacious claw. Based on your limited description of it's use I believe I am trying to use it the same way but I have to be doing something very different.

[David E Keller]

I like the teardrop scraper in the swan neck bar for finishing cuts under the shoulder... I think the broad surface gives me more control with smoothing cuts. I haven't used the carbide cutter much either, but my understanding is that it should e presented to the wood surface at about a 45 degree angle so that it's in a shearing position rather than straight.

[Roger Chandler]

I would really be interested in more details on your technique for using the carbide cutter. So far I have had very little success using it. For me it grabs like the most tenacious claw. Based on your limited description of it's use I believe I am trying to use it the same way but I have to be doing something very different.

JD,

First off, when I hollowed, I would shine a light inside the vase to see if I had the surface pretty level with the larger ribs and humps removed with the regular cutter bar. When it was pretty level, and only had some torn out fibers, etc, that is when I used the carbide round cutter. The bar tip that holds the cutter tip assembly has two set screws one on the end of the tip and one on the top of the bar [both tighten the cutter assembly in place]

I had the cutter assembly bar [the one that has the carbide cutter attached] at an angle where the top of the bar was in such a configuration that the set screw did not set against a flat on the bar, but on a ridge between the flats, and the set screw in the end of the tip was pressing against a flat on the 45 degree angle bored into the bar tip to accept the cutter assembly.

I just took light passes and tried not to press too firmly against the side of the form. I had a couple of small ribs [humps] left by me, but with the light passes the carbide cutter tip went through them without a problem.

I was actually a bit surprised by it all...........the last time I tried using that tip it did catch a lot on me, but I think repositioning the cutter head to the angle I did made a great deal of difference.

I kind of followed what I had experienced with my hunter tools that have the same type of round cutter on them.......I figured the angle that worked best when I held them by hand would probably work the best for the monster rig as well, and it worked.

[Jamie Donaldson]

All hollowing tools should ALWAYS be used above the center line, so if there is a catch ( I have heard of such things happening?) the tool swings out into open space. If a catch happens below center line, the cutter rotates deeper into the wood, and your vessel just became either a vase or kindling!

[Bill Wyko]

I would suggest building a steady rest with some in line skate wheels. I have a clark system but you can make one from birch plywood pretty easily. This is my system.
http://www.theokspindoctor.com/graphics/hollowtr.jpg

[Bill Bulloch]

I got one of those and just for the heck of it I tried it. Mine has a 3/8" thick, 1.25" wide platfrom, so after you center the cutter you will have to have a fairly large opening in order to get the toolrest inside the vessel and the cutter centered. I was working with a 2" hole and could not get the cutter centered without the toolrest rubbing the opening of the vessel.

[Roger Chandler]

Thank you Bill W. .........I was using a steady rest when I got the chatter.........mine has 4 wheels.

193850

[Baxter Smith]

No "experienced user" here but I did build something similar out of 1" square stock that extended about 4" into the mouth of a vase. Wouldn't work for small openings but it did allow me to complete something I was making.