Author Topic: Vacuum bagging rigs - mini to maxi  (Read 7684 times)

surfcowboy

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Re: Vacuum bagging rigs - mini to maxi
« Reply #15 on: March 10, 2017, 06:49:31 PM »
Bean, peep those gasts on eBay. Or someone who's got some experience test one of those medical pumps.

I think the shop vac to empty your bag would make a smaller pump feasible.

Bean

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Re: Vacuum bagging rigs - mini to maxi
« Reply #16 on: March 10, 2017, 08:42:57 PM »
I was checking out a small Gast and It looks like some of the smaller ones pull less than 1 CFM.  Might be enough for my projects.

PonoBill

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Re: Vacuum bagging rigs - mini to maxi
« Reply #17 on: March 11, 2017, 09:48:21 AM »
1CFM is plenty once you get the bag snug to the board. A vacuum cleaner is perfect for that, pulls the bag down in seconds. Then you could use your oiler to get the vacuum down to maintenance level and find any leaks, and finally, rely on the little Gast with a cycling setup to maintain. That might sound complicated, but it's simply two valves teed into your suction line. Close the vacuum cleaner valve when the bag is deflated and turn off the vac, close the oiler valve when you get to holding pressure and let the cycling pump maintain.

I do the vacuum cleaner trick even with my 4CFM rig with its 3ftcu holding tank. I don't turn on the cycling pump until the bag is collapsed and I've made sure I don't have any wrinkles in the bleeder cloth. You can cycle the vacuum cleaner on and off to get everything right. It feels like a huge step back to release the vac when I only use a pump. I left a hose section across the bleed cloth once because I didn't want to do the do-over. Left a groove in my glass. Stupid. Would have been a 30 second fix with the vacuum cleaner, ten minutes that might have let the resin kick too much before being squeezed otherwise.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

supuk

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Re: Vacuum bagging rigs - mini to maxi
« Reply #18 on: March 11, 2017, 02:30:33 PM »
the small pumps I think would be fine for small moulds or repairs however if you intend on doing larger  which lets face it if you have the ability you will (surfboard size to sup size) for the sake of what a larger pump costs save the time and effort of have to re do your set up and probably a bugerd blank and lam when you find you don't have enough volume its worth just doing it right from the start. I know I wish I had!

From my experience I like to re use the bags that I have for doing boards a good few times before having to replace them, its not cheap when they are even 12'  long and its a huge waste of plastic if you do replace them every time you bag something and considering a board is going to get baged minimum of 2 times if not 4-6.

When you are trying to resell board in to bags that are on a rack in a relatively small space you soon start to develop lots of tiney pin prick holes. while you can sometimes find them and plug them often you are left searching for half or even a hour while you panic trying to get the vac down. Even with my big pump I have this problem but luckily have a second I can hock up in emergency's and has saved my bacon a good few times.

It seams unlikely that if people are not going to spend a bit extra on a big pump then you will replace your vac bags on a regular basis enuf to insure no holes.

PonoBill

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Re: Vacuum bagging rigs - mini to maxi
« Reply #19 on: March 11, 2017, 02:50:06 PM »
I reuse mine more often that that, but I have a lot of space and I'm careful with them. I still get holes, but the ultrasonic detector makes short work of them.  I keep some sealing goop handy. I don't do full boards that often, but I did some serious mods on my busted 18' speedboard. I did five pulls on that sucker to make the tunnel. Fixed holes every pull because I was using a soft, flexi bag to get down to the bottom of the tunnel.

I learn new stuff all the time. The vacuum cleaner thing is a fairly recent improvement, and it's proven to be a big deal. I can't find leaks with it, but it gets the bag down onto the board in 10-20 seconds, even drawing through the small hose that goes to my bag adapter. I'm going to make a larger diameter hose and bag adapter (using bits from a sander vacuum line that my Festool obsoletes) that will connect to a resin trap (probably unnecessary, but I already have it) then to a manifold that connects the festool vacuum cleaner with a 1" diameter ball shutoff valve on one end and step down to my pump hose size on the other. I've got all the bits, just need to put it together. I'll shoot some pics when I'm done.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

Biggreen

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Re: Vacuum bagging rigs - mini to maxi
« Reply #20 on: March 11, 2017, 04:22:13 PM »
I believe the Gast pumps are the be all end all in vacuum pumps. And those medical aspirator pumps are designed to run 24/7 365. I remember reading on Swaylocks that a number of people swear by them.

I too got my stuff from Veneer Supplies. Good stuff, but if I had a minor beef its that they also charge a handling charge, so you get charged 3 times. Price, shipping, handling. Just raise your prices a little. Minor, like I said.

My pump is a Thomas I got on eBay. I've used the shit out of it. There's been a few times when I couldn't track down a leak and the damn thing would cycle way too often. I'd just put a fan blowing on it and keep going. Damn thing won't die. I'm gonna get a Gast for a back-up.

My rig.

supuk

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Re: Vacuum bagging rigs - mini to maxi
« Reply #21 on: March 11, 2017, 08:50:26 PM »
I reuse mine more often that that, but I have a lot of space and I'm careful with them. I still get holes, but the ultrasonic detector makes short work of them.  I keep some sealing goop handy. I don't do full boards that often, but I did some serious mods on my busted 18' speedboard. I did five pulls on that sucker to make the tunnel. Fixed holes every pull because I was using a soft, flexi bag to get down to the bottom of the tunnel.

I learn new stuff all the time. The vacuum cleaner thing is a fairly recent improvement, and it's proven to be a big deal. I can't find leaks with it, but it gets the bag down onto the board in 10-20 seconds, even drawing through the small hose that goes to my bag adapter. I'm going to make a larger diameter hose and bag adapter (using bits from a sander vacuum line that my Festool obsoletes) that will connect to a resin trap (probably unnecessary, but I already have it) then to a manifold that connects the festool vacuum cleaner with a 1" diameter ball shutoff valve on one end and step down to my pump hose size on the other. I've got all the bits, just need to put it together. I'll shoot some pics when I'm done.


yes I probably get 20 30 pulls per bag doing full boards but by that point the second vac is running a fare bit. I will have to try get one of those leak detectors to see how well they work.

 I haven't tried them as yet but but plan to when i get back to the uk and replace all my bags with a few of the valves of the vac bags that you get from those bags you use with clothes and a house hold vac to make the bulk removal fast and easy. normally I just have a small slit that I just suck through and then tape over.
« Last Edit: March 11, 2017, 08:52:53 PM by supuk »

PonoBill

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Re: Vacuum bagging rigs - mini to maxi
« Reply #22 on: March 11, 2017, 11:46:30 PM »
DW is the one who told me about them, I've listed most of my good ideas about glassing from him. It's the first thing I take out if I'm going to do a vacuum bag.
Foote 10'4X34", SIC 17.5 V1 hollow and an EPS one in Hood River. Foote 9'0" x 31", L41 8'8", 18' Speedboard, etc. etc.

 


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