Love those Quick Change Chucks - NOT

[SAA3840]

Really, what was being used before the Quick-Change came along? In my opinion, the QC is probably the machine's weakest link. I currently have five used QCs on my bench. Sure, a couple were ruined because I was new to this hobby. But once I got educated on the proper care and feeding of Quick-Change Chucks, I thought maybe, just maybe I might start seeing them last a little longer.
The last one got babied. I blew out the dust, snapped the collar a few times and lightly lubed the inside and the bit holder with 2in1 oil at every bit change, yet the QC is ruined after about 6 or 7 carves. (All of my bit holders have been replaced, none of them have any BB dents or wear other than the black coating coming off.)
Perhaps a chuck like that used on regular routers would be better? The machine measures each bit twice before it carves with it, once during set-up and again when the bit is loaded for use.

[mtylerfl]

Hello,

Perhaps the problem is that you are using "2-in-1 oil" instead of the recommended "3-in-1 oil".

Seriously, I'm sorry to hear that you're having trouble with your QC's. However, there's no reason for anyone to have to go through that many QC's unless it's over a period of several years or under very heavy-duty use.

I just changed my first QC on one of my machines (in almost two years of use). I'd still be using the original if it hadn't been damaged due to an improperly mounted cutting bit which caused excessive runout which led to premature QC failure. The other machine is still running the original QC and shows no sign of needing replacment yet!

From what I gather, one of the most common causes for premature QC failure is that a bit was not fully seated in the chuck. Here's what I do to make certain there is no "play" or runout in the bit due to a seating issue...

1) I use a mirror and a flashlight to inspect the underside of the QC between every bit swap and after every project. I "scrub" the QC with an old toothbrush to remove the bulk of any sawdust residue. Then I use a wooden toothpick to dig out any packed sawdust I can see in the crevices. After it is cleaned, I swab the inside of the QC with a little 3-in-1 oil on a finger before putting in a bit and/or after each project.

2) When I snap a bit into the QC, I use the mirror to verify that the two red indicator marks are touching each other. These red marks are only visible from the underside of the QC. They do not necessarily have to be absolutely "centered" with each other, but they do need to be "touching". Even if you think the bit is snapped securely in place, you should verify that the red marks touch - if they don't, then the bit is not fully seated and will be prone to runout and damage will be caused either to the QC itself or the bit adaptor, or both.

I have found that even the smallest amount of packed sawdust in the QC can prevent a bit from making a secure seating. Even the powdery, super-fine dust needs to be removed to assure success - especially if the user is carving MDF - the nasty stuff gets EVERYWHERE and packs in tight to boot.

Another thing - inspect your bit adaptors on a regular basis for indentations (called BB marks - ball bearing marks). If you see deep indentations, it means the QC and/or the adaptor needs to be replaced because those indentations will allow bit runout due to the "slop" caused by the BB marks.

My bit adaptors have almost imperceptable marks from the BB's after almost 2 years of use. So tiny, they are of no concern. That's OK and is normal. However, if the indentations become easliy noticable, it will be time to replace both the QC and adaptors. This is normal wear and tear over a long period of time (or after extended heavy use). Occassionaly I have heard of folks noticing deep indentations very early on in their adaptors. This can 'always' be traced to using the machine when a bit is not fully seated and that's what causes the premature wear.

I hope these tips help you avoid any future mishaps and contribute to the enjoyment of your machine.

[Digitalwoodshop]

I think an increase in hardness of both the QC and Bit holders is needed. Anyone have access to a Rockwell Hardness tester to see what the numbers are?

It is a Cash Cow for LHR in lifetime spare parts. Not like Cut Motor brushes that you could find if you really looked hard on the open market. The QC is a LHR designed product.

It lends well in quickly changing bits and the placement of the bit length the same every time. But needs to be hardened more.

OR.. A Titanium QC like the new Kevlar Sand Paper Belts.

AL

[liquidguitars]

OR.. A Titanium QC like the new Kevlar Sand Paper Belts.

I just got a set of the new belts but have not used them yet, very clean looking..

I would think the QC would last more than 6 carves so something could be wrong in the Z truck bearings.

LG

[ChrisAlb]

If the QC is only lasting 6 carves, something is big time wrong. After changing my first QC after 408 cut hours, The second one is doing just as great as the first so far.

I have 3 sleigh carves at 6-1/2 hours each in Southern yellow pine (pretty hard for pine) and Alex's mirror frame 11-1/4 x 36 in Red Oak at 1:28 hogging out the back with the 3/8 straight bit at 1/4" deep x 3/8 passes and the front at 15 hours with just the carving bit at 1/2 deep. Chuck and adapters are fine.

Now my Y belt and or Y motor? That's another story. After pushing the old girl through that oak, the belt stretched and I "think" the motor got weak. I tightened up the belt for now with a washer on the tension screw.

It's weird because it won't make it over to the bit plate unless I push it with my hand (slows down about 3 inches from the bit plate and then just clicks when it touches). But, if I push it so the bit plate comes out and it gets past checking the bit, the Y direction works just fine for the carve and cut outs..

[Digitalwoodshop]

I know if you change the QC but don't change ALL damaged bit holders then you wasted your money and one will destroy the other. Same as putting in a new bit holder in a bad QC... Wasted your money.

AL