Replies

1. 
   Jamie_Buxton | Sep 17, 2002 10:08pm | #1

   I've been using vacuum presses for woodworking about 20 years.  Here's some suggestions for a hobbiest on a tight budget:

   * Make your own bags.  There's nothing tricky about it.  For $20 in materials and a half-hour's labor, you can make a bag that commercial sources would price at $200.  

   * A big vacuum pump isn't required.   Almost any pump designed to make a vacuum will make enough vacuum to press veneer.   A higher-volume pump might be a minute or two faster in getting down to high vacuum, but that doesn't matter much in a home shop.

   * A pump controller is a luxury, and you may not need it.   The controller cycles the pump on and off to regulate the pressure inside the press, just like a thermostat regulates the temperature inside your house.   For a veneer press, you can do without.  The pump will run 100% of the time, and will make its maximum vacuum all the time.    For a home shop, this is okay.

1. 
   MichaelLomax | Sep 18, 2002 06:52pm | #5

   Jamie,

   Can you provide more information on making your own bags?  Do you use vinyl or polyurethane?  If polyurethane, where to you get it?  How about gluing the seams?  Do you use PVC cement? 

   Thanks in advance,

   Michael Lomax

1. 
   Jamie_Buxton | Sep 19, 2002 02:33am | #9

   Michael --

      I buy clear sheet vinyl from a local (San Francisco) retailer named TAP Plastics.   I imagine similar stuff can found in most cities.   The vinyl is 54" wide, and comes on a roll that must have several hundred feet on it.   I use 30 mil material.  It is about $6 per running yard.   I've tried 20 mil material, but got too many punctures; your results may vary.  At the same store, I buy vinyl cement, and 1/4" ID vinyl tubing that fits my vacuum pump.  To make a bag, I glue the edges, feeding the tube through the seam at the far end of the bag from the mouth.  I clamp the seams with a couple boards until the glue cures.   The tube inside the bag extends almost to the mouth of the bag.   I perforate it every few inches with a small bit.   The perforation isn't high precision; air will find the holes.   The tube just flops around inside the bag and drapes over the workpiece.  Or you can duct-tape the tip to the top of the bag, so that when you push a workpiece into the bag it doesn't shove the tube down to the far end of the bag.

      To close the bag, fold the opening over and clamp it with a couple boards.  Or you can make a quick-closure from two PVC tubes.   1/2" Schedule 40 tube is .84" OD.  3/4" Schedule 200 tube is .91" ID.  That is, the difference is four thicknesses of 30 mil sheet vinyl.   (Schedule 200 is the thin-wall stuff used for lawn irrigation.  And no, I can't explain why it is called 3/4" pipe and has an ID of .91"!)  Rip the thin-wall tube to get a C-shaped cross section.   To close the bag, wrap the mouth over the 1/2" tube, and snap the other tube over it.  Ta-da!

        Jamie

2. 
   davamoore | Sep 17, 2002 11:10pm | #2

   Kevin -- For my first vacuum press I recently bought the Compact 100 kit from Vacuum Pressing Systems in Brunswick, Maine.  As Jamie already noted, the pump on this particular unit does not have a regulator so it stays on all the time, but since I don't/won't be using the press as often as some professional shops, it wasn't a problem.

   For my first project, I was planning to veneer a tabletop and create a curved, bent-lamination apron for a demilune table.  Veneering the tabletop used the standard 49" x 49" bag that came with the kit; creating the curved apron required me to build a form on which to clamp the vacuum bag with the laminations inside; knowing I'd probably do several of these, I also bought the 8" x 12' 30mil vinyl bag.  Having a second bag that fit the job made the lamination process much easier.

   I also bought the Unibond 800 glue, and was given a two-for-one deal on a couple of instructional videos.  The videos were great... no Academy Awards here, but they SHOWED me how/what to do and what to watch out for.  For me, "live" demonstrations are often an easier way to learn (although the instructions that came with the kit and "extras" that I ordered were also very clear and easy to follow).

   The ordering process was easy, the shipping was fast and accurate, and any questions I had that weren't answered in the instructions or videos were already asked/answered on the company's website forum.

   My first projects came out perfectly, I'm pleased to report.  (Of course, I made a few goofs after the fact, but they had nothing to do with the vacuum press, veneer or bent laminations, just my stupidity... fortunately, I've learned some about fixing mistakes.)

   Anyway, I probably sound like a shill for Vacuum Pressing Systems, and I have not tried any other manufacturer's or retailer's products, but I was/am completely satisfied.  My vacuum press is likely to get a lot of use in the future.

   Having never tried the hammer/hide glue method, I can't make a comparison.  Who knows, having recently discovered the joys of hide glue, I may give that a try someday, too.

   David

   Hmmm... the garden or the workshop today?
1. 
   Glendo | Sep 18, 2002 07:29am | #4

   I bought the same vacume press and after four or five medium sized jobs I think I'd buy the same one again.

   Glendo.

2. 
   KevinLBS | Sep 18, 2002 08:59pm | #6

   First off I'd like to reiterate Michael's question to Jamie about making bags.  I've heard of heat-welded seams (basically melted together) but I imagine there's a perfect adhesive for it too.

   Now, Davamoore-

   I'm glad to hear you like the model from Vacupress.  I actually ordered their catalog last week before I even posted this.  You and Jamie easily convinced me about having a pump that stays on.  Question though- is it super loud?  Will I wake up my soon-to-be-newborn child with it running?

   Funny how noise levels of my tools are all of a sudden important to me...

   OK, I'm gonna do some research now on where to get 20-30 mile vinyl or urethane

   Kevin

1. 
   Krico | Sep 18, 2002 10:03pm | #7

   While I don't yet have a vacumm press, there is a good website at http://www.joewoodworker.com .  At that site, he shows how to inexpensively make your own press and make your own bags. I have no affiliation with that site.

1. 
   efarmer4 | Sep 19, 2002 08:11pm | #12

   Thanks for the link! ( http://www.joewoodworker.com )

   Did anyone notice the "Fiber Optic Table"?? Wow! Never thought of that. Not sure I like it.... but...maybe it looks better in person.. when he said he'd used a walnut burl veneer top, I thought perfect wood choice!

2. 
   Glendo | Sep 19, 2002 03:13am | #10

   I set my pump on an inch thick foam pad. That keeps it from walking across the bench and seems to absorb most of the sound. It only produces a low hum.

   Glendo.

3. 
   dondownunder | Sep 19, 2002 05:09am | #11

   My bags are 0.75mm (0.030") and they came from an auto trimmer. This stuff is used for the windows on soft tops. I don't remember the price but it wasn't dear. Stuck the seams together with contact adhesive. The good thing about this stuff is you can make several different bag sizes, & can even run a couple at a time.

   Don

4. 
   davamoore | Sep 19, 2002 10:54pm | #13

   Kevin -- Regarding the noise level of the Compact 100, I first have to say that I'm lucky enough (unless there's a lot of snow) to have my shop about 100 feet from my house, in an outbuilding.  The pump could scream like a contractor's table saw and I still wouldn't hear it.

   On the other hand, I don't find the unit to be especially loud.  To me, the noise level is somewhere between having a three-speed, $20 Wal-Mart room fan on medium and turning it up to high.  And, like a cheap fan, the sound is more like a white noise than an intrusive screaming or banging.  I usually don't hear it until I'm a few feet from the door of my shop.  Depending on where it's located, I'd say the worst-case scenario is that it would provide a sort of white-noise... it might even help your baby sleep!

   I'd second the idea of putting it on foam rubber.  I haven't done that myself, but I do clamp it to my workbench to keep it from walking around overnight, and that seems to dampen unnecessary vibration.

   Hope that helps,

   DavidHmmm... the garden or the workshop today?

3. 
   georgetroy | Sep 17, 2002 11:28pm | #3

   Hello Kevin,

   I just recently brought the Nova DVR 3000. It is close to your price range and is available from Woodcraft. The DVR will turn 16" with a computer speed range of 250-3500. This lathe is smooth and will give you great cuts without vibration. Go to shop pics on my web site for a view of this lathe. George Troy

   http://www.georgetroygraphics.com

4. 
   Hempstalk | Sep 19, 2002 01:10am | #8

   Hi kevin.  In my opinion the best thing you could do would be to decide what you intend to do with the press before you buy as that will completely dictate what level of press you need.  As mentioned you can get a diaphragm pump which is the pumps that run continuously for a very reasonable price.  Their sold as compact units ready to go.  These units are great to get going and do some small to mid size projects.  I have a friend who builds furniture that purchased one of these units and has been very happy with it.   If you intend to do larger items like dining table tops or large thin strip laminations these pressing systems might fall short.  In those cases you might want to get a automatic pump that runs around 5cfm.  These pumps will evacuate the air quickly and turn themselves off when the desired vacuum is reached.  This is nice because who want to listen to that thing running for 10 hours.  The diaphragm pumps are definitely quieter but draw only about .75 cfm.  Bags are easy to make as mentioned and I have an assortment for different purposes.  I do have one very good bag I use for demanding or large jobs.  It's a seamless 54" by 109" 20mil polyurethane.  It's not as tough as a 30mil but has a little more stretch to span concave presses and things of that sort.  Sealed with the common pipe and c channel this bag will stay for 9 or more hours and never turn the pump back on.  No leaks.  I use a 5cfm pump and it preforms well and I don't think I will need to ever upgrade.  As far as manufacturers I think Vacupress has many good systems for all ranged and a few nice details like a exterior filter for easy cleaning and quick connectors.  They also use 3/8" inside diameter hose for quick extraction.  I don't have their press simply because they don't carry seamless bags which I wanted.  Simply a matter of preference though.