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View Full Version : what type of vacuum pump/chuck



curtis rosche
03-18-2009, 4:59 PM
ok, so after make enough bowls, and being satisfied with my skill, now i am disgusted witht he way the bottoms look. i am looking at vacuum pumps over at the Bay. they have cheap pumps. what type should i be looking for? and once i have the pump, what do i need to use it with my lathe? my spindle is 3/4x16tpi

curtis rosche
03-18-2009, 5:09 PM
here are a couple i found,

GAST Model DOA-P704-AA Vacuum Pressure Pump!!

This pump is in very good physical and functional order. It has two working gauges. These retail for over $700 new. This is a fairly new pump and hasnt been in service for long (maybe one year).
Free Air Displacement: 1.1cfm
Electrical: 115v/ 60 Hz/ 4.2 Amps
Ultimate Vacuum: 25.5" Hg
Pressure: 60 psi


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GAST Vacuum Pump NEW 0523-101Q-G582DX Compressor

Vacuum Pump Power Rating 1/4 HP Voltage Rating 115/230 Volts Current Rating 4.6/2.3 Amps NPT Inlet (F) 1/4 Inch NPT Outlet (F) 1/4 Inch Phase Single Length 13 1/2 Inches Width 5 1/2 Inches Height 6 Inches Free Air Flow @ 10 PSI 3.9 CFM Free Air Flow @ 10 Inches Vacuum 3 CFM Free Air Flow @ 15 Inches Vacuum 2.2 CFM Free Air Flow @ 20 Inches Vacuum 1.4 CFM Free Air Flow @ 25 Inches Vacuum 0.5 CFM Free Air Flow @ 5 PSI 4.4 CFM
----------------------------------------------------------
SPX Robinair Cooltech Vacuum Pump Model 15600
Specifications:
Free Air Displacement:
6 CFM
Number of Stages:
Two
Factory Micron Rating:
20 microns
Intake Fitting:
1/4" MFL
Oil Capacity:
15 oz. (445 ml)
Motor Size:
1/2 HP
Voltage:
115V, 60Hz
Weight:
27 lbs (12kg)
Dimensions:
9 ¾" H x 5 5/8" W x 15" L
(24.7 cm x 14.25 cm x 38.1 cm)

-----------------------------------------------------------

Mike Minto
03-18-2009, 5:12 PM
So I use the HF 2.5 cfm vacuum pump, and am getting over 25 HG on the vacuum gauge - and it's MUCH less $. mike

curtis rosche
03-18-2009, 5:14 PM
also this one

SARGENT-WELCH SCIENTIFIC CO., SAR-VAC MODEL 8804 VACCUM PUMP

if one of these will work please let me know. if you are one of the CL addicts around here who constintly searches it, let me know if you find any thing good on your adventures. my computer is to slow to do the search of multiple craigslists at one once.

curtis rosche
03-18-2009, 5:16 PM
so, i take that as a vote for one of the gast pumps? which one?

Richard Madison
03-18-2009, 5:19 PM
Curtis,
From everything I have read here, the 1.1 cfm capacity is probably too small if your bowls have much porosity. Have you tried doughnut chucks or jam chucks? Certainly a vacuum chuck system would be very handy, but you don't actually "need" one to make bowl bottoms look good.

curtis rosche
03-18-2009, 5:27 PM
well, Rich, i looked at donut and jam chucks, but heres the problem. most of my bowls latley, and all of the future ones that i am going to make from the reclaimed wood i got, fit my lathe exactly, i take a file to the blank just to get it to spin. i leave them as big as possible, and because of that it would mean that a chuck would not fit around the bowl to hold it.

dont vacuum chucks work better anyways? except for really pourous woods (what woods are they?)

Richard Madison
03-18-2009, 5:34 PM
Jam chucks would still work. They are not necessarily larger diameter than the workpiece. Having never used a vacuum chuck, I can not say if they are "better" or not. For very porous pieces one can cover most of the outside with plastic wrap film to help seal it while on the vac. chuck.

curtis rosche
03-18-2009, 5:40 PM
these were all under $50 Mike

curtis rosche
03-18-2009, 5:46 PM
i also found this one, from the place that Steve sites in his how to article on SMC
http://www.surpluscenter.com/item.asp?UID=2009031816413208&item=4-1669&catname=

1/4 HP Rotary Vacuum Pump/Compressor
Used, GAST model 0522-P335-G509DAX. Direct drive, oil-less rotary vacuum pump/compressor. Thermally protected motor.

SPECIFICATIONS

HP 1/4
Voltage 220 AC
Amps 1.5
RPM 1725
Duty continuous
Ports 1/4" NPT
4 CFM at 0 in. Hg
20 in. Hg max vacuum
PSI 10 cont.
PSI 15 max.
Size 11" x 5-3/4" x 8"
Shpg. 31 lbs.

David Walser
03-18-2009, 6:25 PM
Curtis,

Most of the Gast pumps available second hand are 220v (because they are used in commercial applications). Every now and again you can find the 110v version on ebay or surplus supply center (or whatever). In general, you are looking for the rotary vane model in either an oiled or oil less version.

Several forum members have bought the 2.5 CFM vacuum pump from Harbor Freight. It's a rotary vane model that requires oil. (Be sure you keep the oil reservoir full, or the pump's life will be shortened.) This is a relatively new item at HF, so we don't know how reliable these pumps will be. (Gast pumps have a great reputation.) Here's a link: http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=98076

As for how to hook the system up, take a look at Steve Schlumpf's excellent tutorial and search the forum for photos and descriptions of other forum members' setups.

Good luck!

Jason Clark2
03-18-2009, 6:55 PM
I ordered a Gast 0522 (http://www.surpluscenter.com/item.asp?UID=2009031817503497&item=4-1669&catname=) last week and expect to receive it on Monday.

I'm making my own rotary adapter and vacuum chuck this weekend and plan to use Steve's tutorial as a guide to acquire and assemble the remaining parts.

Jason

Mike Stephens
03-18-2009, 7:36 PM
Where can I find Steve's article? I did a quick search but could not find it.

Jason Clark2
03-18-2009, 8:01 PM
It's been moved to the articles section:
http://www.sawmillcreek.org/showthread.php?t=84279

Jason

Mike Minto
03-18-2009, 8:12 PM
hey, i'm glad you found a pump for less - wish i had found a 110 gast for that price, i would have bought that. mike

Scott Conners
03-19-2009, 3:10 AM
I finish all my bowl bottoms using my chuck as a friction chuck. Just open the jaws, fold a nice paper towel as padding, then pin the bowl against the chuck with the tailstock. I shape the bottom, then part the 1/2" tenon left over down to almost gone, use a Japanese flush cut saw or a chisel to cut it off, and 1 minute of hand sanding and it's gone. I do use my large jaws (~4" size), and it works great. I'm always worried about catching and knocking the alignment off with my cole jaws. This way I can finish bowls as big as my lateh can turn as well.

Jeff Nicol
03-19-2009, 6:45 AM
Curtis, I just bought the HF 2.5 pump and it will suck living daylights out of any bowl you will be able to make on your lathe! It does not have to be a Gast pump to do the job. I used an old compressor out of a dehumidifier for years and it still works fine. I just have a friend working at HF so I get his 20% discount that is why I got the new one. I am not sure you understand what a jam chuck really is either. A jam chuck can be anything put on the headstock to hold the bowl in place while the tailstock is brought up to hold the bowl while you finish turn the bottom of the bowl. You will have a little nub left to carve off and sand a bit but it is cheaper than buying a bunch of things for a vacuum system right away. I have only used my vacuum chucks maybe 10 times in 5 years and it is quicker to use a jam chuck most times.

Jeff

curtis rosche
03-19-2009, 6:45 AM
so which one of the first four i posted is best? they are cheaper than the harfor freight and surplus center ones

Paul Andrews
03-19-2009, 8:29 AM
Curtis,

WHich one is best is always subjective! The bottom line in a vacuum pump is the amount of air it can move. With a perfect seal all of the pumps you mentioned would probably work. Obtaining a perfect seal is not likely and the reason you need the ability to move as much air as possible to obtain the best hold.

I own several gasts pumps, one of which was purchased from surplus supply. Gast makes commerical vacuum pumps that are designed to run 24/7 for years. All of the pumps I own are oil less, as I did not want to deal with the potential mess.

The first gast pump you mentioned the DOA model does not provide enough air movement, in my opinion. The 0523 model I use and have had excellent results with.

Ralph Lindberg
03-19-2009, 12:04 PM
Curtis, I just bought the HF 2.5 pump and it will suck living daylights out of any bowl you will be able to make on your lathe! ....

Jeff

On the reccomendations of others, I have that one (98076) on order (and due in this week). Be aware it is an oil pump and requires a good airfilter. The strong point is it only costs between $70 and $80 dollars (they vary their price), plus any discount

I have a 15% off the entire order and a 15% off one item coupon, plus a $10 gift card, so there are lots of discounts you can get.

curtis rosche
03-19-2009, 1:59 PM
whats the base amount of suction to look for in a pump?

Ralph Lindberg
03-19-2009, 6:40 PM
It depends.... You need a bleeder valve so you can adjust the vacuum, or you run the risk of crushing the bowl.

Swag, 2 CFM at 26 inches with a valve so you can adjust it down to some lesser value

curtis rosche
03-19-2009, 8:39 PM
how about this pump?
Refco Two-Stage 6.4CFM Vacuum Pump RL-8

Ryan Baker
03-19-2009, 9:03 PM
It's been moved to the articles section:
http://www.sawmillcreek.org/showthread.php?t=84279

Jason

Thanks for that link, and thanks to Steve for writing the article. That rotary adapter is just the ticket, since I have the same lathe as Steve. Add that to my to-order list. :)

David Walser
03-19-2009, 11:17 PM
how about this pump?
Refco Two-Stage 6.4CFM Vacuum Pump RL-8

Curtis,

You don't need a two-stage pump, nor do you need one that moves 6.4 cubic feet of air a minute. A single stage rotary vane pump of 2.5CFM is more than adequate for your needs.

Mike Peace
03-20-2009, 12:16 AM
I got my GAST 523 110V used off eBay incl shipping for $91. Works great. My thougts on the advantages of this model are in the following thread. I don't much about vacuum pumps except what I learned from my research in buying one. This is the same model sold by CSUSA for about $400. You just have to be patient and keep looking on eBay. The 110V models tend to go for a few bucks more than a 220V version of the same pump.

http://sawmillcreek.org/showthread.php?t=99878

Jeff Nicol
03-20-2009, 9:23 AM
Curtis, Harbor freight has a 15% off coupon right now so you could get the 2.5cfm pump for less that $80 and it is brand new. The one I have works as good as any thing else. No matter what you get you still need to have the best seal on all your fittings and vacuum chuck. Do some research on a homemade vacuum pump like this one I use most of the time. These pics show the pump the bowl and the amount of vacuum that is being pulled by this little very old compressor from an old dehumidifier! Like I always say if you can build it for almost nothing why spend the money! I only bought the little pump from HF so I can make a vacuum chamber for stabilizing things and other fun stuff! It may not be pretty but it works like you would not believe!

Good luck and have fun!

Jeff

curtis rosche
03-20-2009, 12:28 PM
the reason i asked about the Refco Two-Stage 6.4CFM Vacuum Pump RL-8, is that so far the price on it is very cheap. the other buyers out there seem to pass this one by because it isnt a gast pump and it looks funny because the outside design is all plastic. if i were to get this one, there is a way to limit the amount of suction right?

curtis rosche
03-20-2009, 12:40 PM
here is another one, but i cant seem to find anything else about this one, like how much pull it has, does anyone know?

small vacuum pump, made by Charles Austin Pumps, LTD (england), model CAPEX-2, with hose and holding fixture. The fixture has a neoprene rim, so you can hold your work against a belt sander, for example, and not worry about sanding your finger tips off, or you can hold a piece of wood while you carve it without getting fingerprints on it, e

curtis rosche
03-20-2009, 12:50 PM
R134A/R12/R22/HOBBYIST VACUUM PUMP(3.0)CFM(NEW)

Leybold/Oerlikon TMP 50 Turbo Pump LH-85401 ISO63-K Flange

Bernie Weishapl
03-20-2009, 12:58 PM
Curtis don't know why you can't use a donut chuck. I use one on bowls up to 15 1/2" and don't have a problem. Maybe I am not seeing something here.

curtis rosche
03-20-2009, 1:59 PM
Bernie, i dont have enough swing on my lathe to make a donut chuck to fit around my turnings, and i just dont like the idea of a jam chuck.

Jeff Nicol
03-20-2009, 2:00 PM
Curtis, It seems that you have a lot more to learn about things that woodturners use for each aspect of turning. A jam chuck will work for every thing that you can turn on your lathe if you know what a jam chuck is. Before vacuum systems this is what every one did to put features on the bottoms of there turnings. So here is a quick sketch that explains it very simply. All the information that you are asking the forum to give you is on the internet somewhere all you have to do is find it. If you want a pump buy one, the cost is what is the determining factor. Besides the only time you really use the vac pump is for the last little nub any way, you should keep the tailstock in place until you are ready to finish the last cuts and sand it off.

Jeff

curtis rosche
03-20-2009, 2:24 PM
how do you use that for a hollowform?

David Walser
03-20-2009, 2:36 PM
how do you use that for a hollowform?Curtis, for an example, follow this link: http://donpencil.com/ and click on "JAM CHUCKS" link in the upper left corner.

Good luck!