Air compressor instead of vaccum pump for veneer bagging?

[smorgasbord]

I just upgraded my compressor to a Rolair JCP10 Plus. Quite happy so far. I've been toying with the idea of doing some veneering with vacuum bags and am wondering if my new compressor can drive one of those "vacuum generators" like the Hold Fast V812.

The V812 is claimed to work with air compressor that can produce 2.5 CFM at 70 PSI. My Rolair is specced at 2.4 cfm @90psi, so I assume it seems likely that I'd gain 0.1 sfm with a drop of 20psi.

Any experiences to share? I'd rather not spend another $320 for a dedicated vacuum pump.

 

[luvmytoolz]

You could buy a vacuum pump for the same cost or even far less than that unit. Keep in mind the vacuum pump will be cheaper to run than the compressor.

 

[Packard]

Note:  I posted in the wrong thread.  I will move it shortly.  Sorry for the confusion.

This is an old post.  I found it when searching for “vacuum bagging”.

The most thoughtfully designed holsters that I own are from “Simply Rugged” holsters.
https://www.simplyrugged.com/ecomme...aled-Carry-Holster.cfm?item_id=152&parent=669

They are accurately formed to fit my revolvers, but lack that hard edged detailing that hand boned leather holsters display.

I suspect that they vacuum form a batch of holsters over blue gun forms all at one time in a large bag.  It would explain the accurate forming and the lack of detail.

The pictures don’t show the effect as well as the real thing, but take a look at the images in their website and see if you don’t agree.

The owner is very personable and answers emails.  There is no reason for him to disclose his methods, but a bit of friendly discourse might pry some information from him.

 

[Peter Kelly]

For even less, you can get a vacuum bagging kit that utilizes a $17 hand pump. Works surprisingly well on small parts.https://www.roarockit.com/tap-kits-bags-and-parts/

 

[smorgasbord]

You could buy a vacuum pump for the same cost or even far less than that unit. Keep in mind the vacuum pump will be cheaper to run than the compressor.

The pump I was looking at was Rockler's, which on sale is $320 (regularly $400). The V812 is about $140.

 

[Steve1]

You have an interesting idea.
I see no reason why it wouldn't work, but sorry, I have no personal experience on this to share.

You would be using a lot more energy running a compressor and venturi, rather than a vacuum pump, but if you are veneering once every few months, that is probably not much of a concern.  I don't see an exhaust muffler on that VB-12, so between the compressor and the vacuum generator, it's probably going to be somewhat loud.

I expect most vacuum bags are gong to have some leakage, but am guessing that either the pump or the venturi generator will be able to provide enough flow.  (Exception might be the Roarocket bags, which will be about zero leakage, but the gummy seal is a bit of a pain)  According to Rockler's specs both make same level of vacuum.

I would bet it works just fine. 

 

[mike_aa]

A good place to go for vacuum pressing is Joe's Veneer Supply.  They sell the pumps, kits, accessories, vacuum bags, and veneer.  Great service and easy to deal with.  Not affiliated with them, just a satisfied customer.

Mike A.

 

[afish]

I have several posts about this if you do a search.  I had an old Senco 4cfm compressor that I was about to send to the scrap yard.  I just never used the thing since converting my nail guns to battery models for field use.  I ended up turning it into a vacuum pump which is still going strong years later.  I did it just by reversing the intake & exhaust I utilized the existing tanks for vacuum as well. I did end up adding vacuum sensor, guage, contactor etc. to make it fully automatic I want to say around 100ish bucks.  There are some naysayers out there that says it can damage the valves inside the compressor but I have not had any issues and mine is hooked up and holding vacuum 24hrs per day 365 days a year.  I seriously never turn it off and still works great.  If you have a spare compressor laying around like I did I would say go for it. A search here, youtube and the previous link are your friend. 

 

[rst]

I used the intake valve on my Craftsman compressor after switching from using my shop vac as a vacuum source for years, made hundreds of plastic parts this way with my homemade jigs and patterns,  I finally bought a used 220v HVAC vac pump from local surplus guy for $15.00 and used that with Virutex and now with Festool's two clamps.  Recently bought a 120v vac pump off Amazon as I still Do not have 220v in my new shop yet.

 

[luvmytoolz]

You could buy a vacuum pump for the same cost or even far less than that unit. Keep in mind the vacuum pump will be cheaper to run than the compressor.

The pump I was looking at was Rockler's, which on sale is $320 (regularly $400). The V812 is about $140.

The pumps I saw are below $100 on Ebay, I have a couple and they work a treat for resin work for me.

 

[Steve1]

You can also buy venturi vacuum generators for far, far less than the V812 OP found at Rocklers.

Since this is a Festool forum, which are premium tools, lets not search for the cheapest piece of made-in-China that may last for a little while.

 

[luvmytoolz]

You can also buy venturi vacuum generators for far, far less than the V812 OP found at Rocklers.

Since this is a Festool forum, which are premium tools, lets not search for the cheapest piece of made-in-China that may last for a little while.

If you're referring to the ebay ones, that are usually what most local suppliers import and sell, the two I have I've been using the last 6-7 years (or maybe longer). I'd call that very good value and service. Conversely the oil less vane pump I imported from the States that was 4 times the cost lasted around a year before failing.

 

[Steve1]

No moving parts in a venturi vacuum generator. 

Never going to fail (although his compressor could).

 

[luvmytoolz]

No moving parts in a venturi vacuum generator. 

Never going to fail (although his compressor could).

They're handy, but still require an air compressor which pulls much more power than a vacuum pump (and is usually far noisier unless it's a silenced one), and most venturi's generally don't reach the same level of vacuum. Probably more than adequate for veneering, but for resin infusing I wouldn't use one though. I had some Robinair's that never got close to the claimed theoretical hg value.

 

[peter halle]

I bought a vacuum pump years ago instead of the Venturi I already had due to several issues:
1.  Noise
2. Simplicity
3.  My compressor at th time was not rated for continuous duty.

I love my JC-10, but I doubt that it is rated for continuous use and really don't want to potentially shorten its life due to it running continuously for a handful of veneering sessions.

Peter

 

[smorgasbord]

I love my JC-10, but I doubt that it is rated for continuous use and really don't want to potentially shorten its life due to it running continuously for a handful of veneering sessions.

That's a good point. The manual says:

...this I series is not rated for 100% or continuous duty, and performs best when given as much rest as run time. If, in order to keep up, you find your compressor consistently running more than five out of every ten minutes then you'll likely need to shore up some air hose leaks or use a bigger air compressor for the job.

So I guess the question comes down to how much bag leakage I'll have.

 

[Steve1]

So I guess the question comes down to how much bag leakage I'll have.

You could use the Roarockit bags.  They use a gummy seal, which can be a bit of a pain, but really are zero leakage.  But if you go that route, you might as well get the roarockit handpump.

I have their system.  It works.  Lots of videos on youtube. 
I find after pumping the bag out, give it a few minutes and then a couple more pumps to remove any air that may have seeped out of crevices.
A vacuum gage is not part of the basic package, but buying the gage might be a good idea.  I can't help but to go back every 10 or 15 minutes to give it a couple of pumps to check it is still at full vacuum.
Eventually, you will get enough sawdust or other debris on the seal that it stops sealing.  They give you one spare seal, and you can buy more.

Lots of veneer (sapele) on my current project.  All done with Roarockit.