Quantcast
  • We invite you to join UKWorkshop.
    Members can turn off viewing Ads!

Vacuum Veneer Press

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

mudman

Established Member
Joined
11 Feb 2004
Messages
881
Reaction score
0
Location
Trying to stay in one piece in South Wales
Was perusing the Axminster catalogue the other day and came across this. Blimey, a bit pricey thought I. :shock:

The thing is just a plastic bag with a pump and no way is it worth that sort of money I thought. Why not try one of these?

Is there any reason this wouldn't work?
Just wondering really as I've never done any veneering anyway.
 

Alf

Established Member
Joined
22 Oct 2003
Messages
12,079
Reaction score
0
Location
Up the proverbial creek
Barry,

The second link just goes to the site's homepage, but (educated guess), d'you mean like these? I imagine the amount of pressure it creates might be insufficient? I haven't a clue really. :roll:

Cheers, Alf
 

Neil

Established Member
Joined
7 Oct 2003
Messages
1,016
Reaction score
0
Location
Ireland
Wow - never seen these before, Gidon - do you know if they are any good?

NeilCFD
 

Shady

Established Member
Joined
6 Sep 2004
Messages
838
Reaction score
0
If you don't have a compressor, I've seen a favourable review of the bagpress 'hydromatic' version in Fine Furniture & Cabinetmaking. It uses the venturi principle to evacuate the bag with water flowing from a tap/hose.

Review was that it worked, but was a little slow to achieve full pressure, IIRC. Their kit looks good quality, but still a little pricey
 

gidon

Established Member
Joined
19 Mar 2003
Messages
2,546
Reaction score
0
Location
West Dartmoor, Devon, UK
Neil
I saw it reviewed in one of the mags (sorry can't remember which). The reviewer was using it a project and had no problems. I was close to getting the kit but couldn't decide what I really needed! They were helpful though.
Cheers
Gidon
 

Neil

Established Member
Joined
7 Oct 2003
Messages
1,016
Reaction score
0
Location
Ireland
Interesting stuff - I think I'll have a good read of the instructions for the homemade version from Scrit's link. Thanks Gidon :)

NeilCFD
 
A

Anonymous

Guest
Barry

I have been using a Bagpress quite extensively in a recent project and it works very well both for veneering and laminating (flexible ply anyway). I have been using the larger of the supplied pumps 8, (litres?) but if you're not going to run more than one bag or use the bench clamping idea the smaller 4 would be fine and reduce the cost. It comes with a footswitch as well which I don't really use and seems the same as one I,ve seen in the Axminster catalogue which is pretty pricey. Don't know if you can get it without.

Bagpress website is pretty poor last I looked. If you've got any specific questions let me know. The F&C article was in issue 81 (Oct 2003)

Regards

Roy
 

Steve Maskery

Established Member
Joined
26 Apr 2004
Messages
11,799
Reaction score
138
Location
Kirkby-in-Ashfield
mudman":i6ctqlsf said:
Blimey, a bit pricey thought I. :shock:
Pricey, yes but excellent engineering. I've had mine several years, and whilst it doesn't get used very often, it is perfect when it does. Recently had to buy a new bag, 8x4 wasn't quite big enough. A 10 x 4ft cost me just over £100 - Ouch!. Can't understand why they make them 4ft wide. A standard 4ft sheet won't fit into a 4ft bag, will it?

After years of bodging and making do, I now take the view that the best thing to do is to bite the bullet and buy the proper thing. Substitutes just soak up resources and give inferior performance. Was it Ruskin who said something along the lines of the sourness of poor quality remains long after the sweetness of low price has gone. Only I think he said it more poetically than I can.

If you plan to veneer anything of any size, my advice is, buy a good bag kit.

Cheers
Steve
 

norman

Established Member
Joined
7 Jun 2003
Messages
162
Reaction score
0
hi mudman
re vac press

I have used a home made one for some years now and as it seems to work on atmospheric pressure of 15 psi when the air is sucked out the old hover that i use seems to do the trick.
a link was given by signal to a posting made by me on another forum if you need details . the cost nothing made out of old bits that i had around the workshop. by the way i used contact addisive so once the shape was formed i could remove and trim etc;

regards
Norman
(norman-one)

ps if your box is not strong it will crush if so take care.
 

mudman

Established Member
Joined
11 Feb 2004
Messages
881
Reaction score
0
Location
Trying to stay in one piece in South Wales
Hmm, quite a few points of view there.
I was just musing really as I have no plans to do any veneering just yet, (although I do happen to have some sheets of cherry veneer under the bed). Just noticed the item in the Axminster catalouge and thought that apart from the pump, that the bag looked just like the one I'd recently stuffed a load of pillows into and compressed to a fraction of their size.

Thinking a bit though, I would have thought that the max pressure that can be achieved would be approx. 14 lbs per sq. inch, ie 1 atmosphere.
I reckon that my Dyson is a pretty efficient vacuum pump and I would be suprised if the vacuum was that much better with the expensive version.

I'll have to check out the links above when I get some better bandwidth but I had two double pillowcase-size bags for about a tenner so I think that when I do have a go at veneering that I'll try the cheaper option first.

A few comparison tests would be interesting though.

ps. Sorry about the link, guess that they don't let you to hotlink into their products.
 

ike

Established Member
Joined
24 May 2004
Messages
1,681
Reaction score
0
The best vacuums can manage about 220 millibars pressure, so the effective pressure on the work is approximately 0.8 bar or about 12 psi.
The problem using a vacuum cleaner is that they rely on airflow to cool the motor. I think they might overheat/burn out using them as a vacuum pump - no?

Ike
 

mudman

Established Member
Joined
11 Feb 2004
Messages
881
Reaction score
0
Location
Trying to stay in one piece in South Wales
Okay, so it's not a vacuum pump, it's a vacuum cleaner. I hadn't thought about the problem of cooling and I'd agree that it wouldn't be a good idea to leave it running but I'd assumed that you just suck the air out, switch it off and leave it hoping there's no leaks. :wink:

Actually, couldn't you switch on for a bit. Switch off and allow to cool down. Restart and repeat. Maybe some sort of timer unit could be used?

What kind of pressure can a proper vacuum pump get down to?
Would it make any difference? I mean, 14 lbs per sq. inch is a fair amount of pressure. A quick guestimate and calculation would put the pressure over an area about the size of my hand at over 200 lbs, would that be sufficient for the purpose? I know that I'd have trouble lifting 4 bags of spuds with one hand. :)
 

ike

Established Member
Joined
24 May 2004
Messages
1,681
Reaction score
0
Well, I suppose the best pump could get very low. However, even the best vacuum will only increase the effective pressure on the work by another 15% so a vacuum cleaner'll probably have enough suck. In, saying it wouldn't, I'd forgotten of course, the shutoff valve - silly me! So long as you get the vacuum pressure in a reasonable time, maybe the vacuum motor won't overheat to the point of cooking it.
 
A

Anonymous

Guest
Here is an interesting approach to the problem. I live in Canada and bought one if these from the manufacturer. I've done a couple of projects with it, and it work well. The sealant tape that closes the bag takes a while to figure out how to open as it is pretty aggressive stuff. Once you figure out how to snap the bag apart it works fine.

http://www.leevalley.com/wood/page.aspx?c=1&p=51167&cat=1,250,43298,43314

I am new here....Hope I can share some thoughts and ideas with you all.

Garnet
:p
 

Newbie_Neil

Established Member
Joined
27 Jul 2003
Messages
6,537
Reaction score
0
Location
Nottingham, England
Hi Garnet

Garnet Foster":3o2em2h2 said:
I am new here....Hope I can share some thoughts and ideas with you all.
Welcome to the UKW forum. Feel free to share your thoughts and ideas.

Cheers
Neil
 

Sgian Dubh

Established Member
Joined
12 Oct 2004
Messages
2,290
Reaction score
154
Location
UK
Mudman, given unlikely ideal conditions and theoretical perfect mechanical efficiency of a pump, no loss of vacuum in the bag etc., then the maximum pressure it's possible to exert will be what gravity provides.

Therefore, if gravity is about 13 lbs per square inch at sea level you could theoretically achieve 1872 lbs of pressure per square foot-- which is a little more than Axminster claim for their system.

Given mechanical inefficiencies it seems doubtful to me that a vac-bag of any sort could achieve anything better than perhaps 11 or 12 lbs per square inch. But that'll be more than enough to do a bit of veneering, and we certainly find it effective enough to achieve some quite complex and large laminating jobs out of plywood, MDF, solid timber, etc..

The biggest cause of problems in my experience is not getting the pressure on fast enough. On complex glue ups you're fighting the cure rate of glues and you definitely want pressure on fast.

Do whatever you have to do to achieve that goal.

As to the actual bag, these can be made to suit any project from heavy duty plastic such as that used under concrete foundation slab pourings, but the pre-made offerings are handy.

I've seen reviews of the Lee Valley hand cranked offering mentioned by another contributor, and I seem to remember that they are mixed, but I have no personal experience of using their system. Slainte.
 

Latest posts

Top