I was wondering how many owners of the Grizzly lathe lineup have and use a vacuum chuck system with your setup? Which system do you use…vacuum pump or venturi system? What type of chuck head? I used to use, and still have the HoldFast Venturi system, but back about 5 years or so, I switched over to a vacuum pump, which I like much better, as no compressor needed. Continued on 2nd post due to 1000 character limit…
I use the finely machined aluminum chuck head from Harrison Specialties, hooked to a rigid plastic tube going directly to my Harbor Freight 3CFM, 2 stage pump, which can peg the needle most of the time on most woods. The HF pump is identical to the Robinair pumps one sees online, and mine has operated without issue and is quiet. I use another plastic tube to direct any oil mist into a paint can with lid [hole in center] and the can has a buch of blue shop towels inside to absorb any oil, which is almost none. I’ve not had to add any oil to my pump since first putting it in use. I can’t say enough positive about Harrison Specialties vacuum chuck head…it’s a fine piece of equipment. I can use this on either of my G0800 or G0766 lathes
I use a vacuum pump - - it is a Thomas oil-less that I bought for a little over $100. I bought it from Bob at Frugal vacuum chuck. I use his system of a tube with a sealed bearing at the end that is sealed into a wooden disk tenon that is held by my chuck. On the vacuum side of the disk is a PVC coupling with some Hobby-Lobby (or equiv.) craft foam. It works well and is pretty quiet. What I like is that if I have a chuck mounted on my lathe, all that I need to do to convert it to a vacuum is to slide a 3/8" PVC tube through the spindle (along with the bearing/tenon disk). I don't have to remove the chuck. It takes me perhaps 30 seconds to set it up. And if I need a different shape of the vacuum fitting, I can easily fabricate one out of a piece of wood and a piece of PVC or equiv.
part 2: I tried to make my own adapter and while it looked nice, I had trouble finding a true "sealed" bearing that didn't leak like a sieve. It turns out that there are true sealed bearings and some "non-contact sealed" bearings that aren't REALLY sealed. They are are not much better than just shielded bearings. I could only draw about 4 or 5" of Hg. I threw in the towel and ended up just buying the sealed bearings that Bob was selling. BTW, as you are probably aware, the max vacuum that a person can "pull" is dependent on a good pump but more importantly at your elevation. I live at about 1800 feet above sea level so my max theoretical vacuum is something around 28 " Hg. But actually, even a lower vacuum like 23-25 still has a lot of holding power. According to a Google search, "A good rule of thumb is to decrease the barometer value by 1 inHg for every 1,000 feet of altitude increase".
I live at around 1300 ft. Above sea level. My needle on the vacuum guage will go to 29 hg. On maple, cherry, and some others. Oak and Ash are a bit less, maybe 26 or 27 hg. The Harrison Specialties vacuum chuck head has a sealed bearing and a metal tube that is attached to the bearing center race, and the tube of course runs thru the spindle. I’ve built shop made chucks, and even used the HoldFast chuck headswith both the venturi unit and the vacuum pump. Nothing gives me the hold of using the Harrison head and the vacuum pump combination. Best I’ve ever used.
I have the JT Turning Tools Precision vacuum adapter kit (handwheel and double gasketed insert) and the hub adapter. Excellent set up that uses PVC fittings for various size chucks. I think I have built up 5 or 6 different sizes faced with craft foam. I probably got one of the last ones sold, as the proprietor died just a few days after shipping mine. My pump is a Gast Diaphragm pump I got off of FB market place. It is like brand new for $100, 2 port with dual mufflers; got lucky on that one. I also have an 8" holdfast head. It works great on larger pieces. On solid wood I easily get 28 - 29 Hg with any of the heads. I have a Harrison Specialties adapter too. Not sure what I'll do with it now. Don't really use it. It is a nice piece. Thought about taking the tube off and trying the head with the JTTT system. I just don't want to ruin it. Roger, how long is your oil exhaust tube? I'm have a pump on a stabilization system and was wondering how to capture any oil.
Right now my exhaust tube is probably 40” as due to space limitations, the pumphas to sit on the end of a workbench next to my headstock, and the tube goes down to the can which sits on the floor. My gallon sized metal can has probably 12 blue shop towels inside, and really, my pump has not sprayed hardly any oil into it in the 4 or 5 years I’ve used it. The oil seems to remain at the fill line mark on the pump.
Thanks Roger. Perhaps the trap isn't really needed. I guess it depends on how well the pump seals. Looks like you got a good one. Mine is brand new and has a little "filter" thing on it - a little barrel about 2" diameter and 2.5" long on the top. I'll know more this weekend if mine seals as well because I plan on stabilizing some punky but beautiful apple I have. My first time stabilizing in a vacuum.
Roger, I ordered my vacuum chuck today from simplewoodturningtools it was basically 200 bucks with shipping. I have the harbor freight vacuum pump so will see how it works out once I get it.
I have a Gast pump about 10 feet from my G0766 lathe, with the “controls” right behind the hand wheel. I fit a sealed bearing into a wooden disc, with craft foam around the circumference that fits tightly into the hand wheel. It’s airtight and I can put it in and take it out easily. I also made various size vacuum chucks with wood and PVC. I have to say that I was skeptical, but having vacuum is a game changer. David
