Warning – Just had a Catch!

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687
Location
Harvey, Michigan
Was in the process of thinning down the inside top of a hollow form and felt the control arm rotate ever so slightly. BAM! Had a catch but didn’t blow up the form! Managed to push the cutting tip deeper into the form just as I noticed the rotation! Whew!

Still, it took some doing but managed to smooth out the ripped area inside the form and the thickness went from 1/8” to 1/16”! So, I guess the thinning part worked!

I have the Monster Articulated Arm Hollowing System and wanted to warn everyone to check the set screws that hold the control arm to the body of the articulated arm. See photo below. Like anything mechanical, things tend to loosen up over time when subjected to vibration. I do not have Lock-Tite on mine at the moment but will apply some later. I have labeled parts so everyone knows what I am talking about – even though some of the terms may be incorrect.

Set Screws.JPG Assembly.JPG Proof of HF.JPG

Hope this warning comes in time to prevent others from experiencing the same type of catch! :wave:
 
I've had similar catches, but so far haven't blown one up. It's a pretty good illustration of what can happen if the tool bit is not horizontal, huh?

I'd recommend against using Loctite on the set screws. At some point, you may want to use other boring bars (what you've labeled as the Control Arm) and you'll want to be able to loosen the screws up to do it. I've been using an assortment of home made 1/2" boring bars lately, so those two screws on my rig have been getting a lot of work. I tend to swap the bars out a half dozen times or more hollowing a piece.
 
I'd recommend against using Loctite on the set screws. At some point, you may want to use other boring bars (what you've labeled as the Control Arm) and you'll want to be able to loosen the screws up to do it.

Vaughn,

Unless I misunderstood you, the set screws that I have the arrows pointing at only secure a small shaft that the larger hollow end of the 'control' arm attaches to. Putting loc-tite on them shouldn't make any difference as I have never removed that piece of the arm before and can't see why I ever would. The control arm has it's own set screws used to attach it to the small shaft. I remove and replace the control arm all the time - so would never loc-tite those set screws.
 
Vaughn,

Unless I misunderstood you, the set screws that I have the arrows pointing at only secure a small shaft that the larger hollow end of the 'control' arm attaches to. Putting loc-tite on them shouldn't make any difference as I have never removed that piece of the arm before and can't see why I ever would. The control arm has it's own set screws used to attach it to the small shaft. I remove and replace the control arm all the time - so would never loc-tite those set screws.

Steve, if you remove that small shaft, you're left with a 1/2" hole...perfect for inserting a 1/2" diameter boring bar into. ;)
 
Well, Larry, this is where reality kicks in!

I would love to be able to say that the entire piece is 1/16" but that ain't so. It's 1/16" for the first 2" then ramps up to 1/8" thick. Corner has to be close to 1/4" - as is the base and probably close to 3/16" on the side walls. I'm no Vaughn when it comes to hollow forms but I keep trying!
 
... I'm no Vaughn when it comes to hollow forms but I keep trying!

I appreciate the compliment, but I'm pretty sure mine aren't any thinner than yours. ;) I'm less adventurous than a lot of guys when it comes to pushing the wall thickness. I'd much rather have a one-piece HF with 1/4" walls than a pile of 1/8" thick curved fragments. :D
 
Steve,

I had posted on another forum that I had changed the design to keep this from happening. As with any manufacturing company, or as for me, I learn a lot of things through feed back from my customers and I'm always trying to improve my end product. The new Articulating Arm Hollowing System, (MAP/HD) and the Captive Systems have changed quite a bit. Stronger bearings, different fasteners, larger bores for the tool holders and different & stronger boring bars made from ground tool steel. When you purchased yours, I had to adapt the Arm to the older style of Captive System, this entailed the manufacture of an adapter that would plug into the bar holder of the Arm System that would accept the boring bar and the other tooling of the Captive System. I have since changed the boring bar and mountings on both systems so that they're the same. This way, if someone wants to update later, it won't be a problem and everything that they have will fit. Get with me and I'll try to figure out a fix for your problem

Thanks.
 
You could put a small drop of CA glue. Then if you wanted to take them out a few seconds with a flame will break the bond then you can take them out.
 
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