Step 7: Sealing the First Side

Now begin to peel some of the tape backing on one side and carefully apply the folded side of bagging plastic over, all the while keeping tension from the upper left corner in this picture.

You don't see my right hand in this picture because I'm holding the camera, but if that weren't the case, I'd be applying a little tension from the upper left to the bottom right corner on the lower right corner of free plastic. This helps ensure that we have fairly symmetrical halves facing one another.
Is there a picture of the finished item? <br> <br>I have an adapter for my air compressor that pulls a vacuum. Would this be useful? <br> <br>Not trying to be inappropriate, but: Why would a zip-lock bag fail? I ask this to learn, not to try to make an actual project with a zip-lock bag...
You could try a ziplock but my guess is that it would leak ...even a slow leak would defeat the purpose of the exercise. It really is a PITA...
I'd try sealing it with &quot;tacky putty&quot;---the removeable clay-like stuff that you put posters on the wall with.
Great write-up. I'm ordering supplies as we speak... but what about the bag connector / port? What specifically is that tool (i.e. McMaster-Carr Part no.) or where did you get it? Thank you!
Ahh, I found it on the Fiber Glast website. Apologies... but it's $39.99! There must be a more economical way to connect the pump to the bag.
Thank you for taking the time to do this.<br><br>The sealant tape you are showing, looks like 'Butyl Tape'. I have a roll of it in my basement. It is available at any good building supply that sells metal roofing. Quality metal roofing companies (e.g. Everlast Roofing) require butyl tape during the installation along gable end edges between the rake flashing and the metal sheet. Just ask for butyl tape at a good building supply place. You may not have good luck at a big box store. Just a heads up.
I f ya want to go to the trouble you can use a A/C compressor from a car then all you'd have to do is add a motor of somekind,&nbsp;they already have valves installed and you can pull about 27 lbs( which i believes varies according to your elevation!) Tks for this instructable been wondering about this very thing!
hey tasmaniac - ya you are right.&nbsp; I actually found this pump works okay for really small things but for larger projects like the gas tank i made for my moto, it just wasn't drawing the air i needed to handle a large moulding.&nbsp; if you can find an air compressor kicking aruond, hack it!!!<br /> <br /> tojours,<br /> Adam<br /> <br />
LOL yeah I already have one! I put hoses on one way and use it as a vaccume pump then switch the hoses and use it for compressor to run my air brush!
Srry what i was interested in was&nbsp; the homade vaccume bags! I figured they would make great storage for my seasonal big game hunting clothes!
I built a vacuum pump out of an old fridge compresser to use as a desoldering station. My question is: Does anyone have any ideas about how to build a trigering device, so the the vacuum does not run all the time?
I don't but I'd love to see how you made your vacuum work...
I used a vacuum advance from a car distributor, soldered on a tab that activated a heavy duty microswitch which was connected to the compressor's power. I used springs adding more to get different vacuum levels, wasn't an exact science but it worked. :)
Just a quick question - what did you use to tint the resin?
ah yes, the tint came from the epoxy resin distributor. I've used resins from both West Systems and Tap Plastics and both sources offer tinting for their products...i've been pretty happy with the black you see here. Have no idea how well the other colors stand up to UV light, tho...
Shortshift thanks for mentioning our kit. We have never really had a problem with offgasing causing loss of vacuum in our Roarockit Thin Air Press system. You may see a small loss of vacuum right after the initial pressing. I check my pressing for the first five minutes. Ten seconds of pumping with the manual pump always beings it back up to full vacuum. The small loss of vacuum is cause from the trapped air being pulled from the skateboard veneers and foam mold. Even when use epoxy in the Thin Air Press there seems to be no problem with holding vacuum. We have actually left sealed bags sit for months while travelling to find them still holding vacuum when we return. Ted from Roarockit
Here's a YouTube video of a guy demonstrating vacuum bagging of composites.<br/><br/><a rel="nofollow" href="http://youtube.com/watch?v=s12pUg9ypVU">http://youtube.com/watch?v=s12pUg9ypVU</a><br/><br/>(He's doing a bunch of carbon fiber motorcycle parts in a big bag, with an electric pump, but its basically the same deal, if anybody wants to see it in action. That video series isn't bad. If you look at the &quot;related&quot; tab you can find the episodes demonstrating the layup, etc.)<br/><br/>I suspect that the bike pump will work for big bags---maybe even Trubuchet03's fairings---if your bag is well-sealed, you have a reservoir, and you suck most of the air out with a vacuum cleaner first. After that, you just need to pump now and then to keep up with the solvents outgassing.<br/><br/>
Nice :)<br/><br/>An alternative (and less likely to leak) method for going around corners with sealing tape is to place your thumb on the tape on corner (maybe slightly before to allow clearance) and force the tape to make a rounded edge. The stuff is stout enough that it will handle it just fine and maintain its seal abilities :)<br/><br/>Always keep in mind that the worst thing you can do to a vac-bag part is to apply a vacuum, and then release it (you're basically forcing air into places that you just displaced of resin :/)<br/><br/>I didn't go too far into vac bagging details - but here's a larger part made and vac bagged (for inspiration and such :p) :)<br/><a rel="nofollow" href="http://www.instructables.com/id/%5bVideo%5d-Part-Making/">Large Part Making</a><br/>
Hey, that's a good point about contiguous tape! the tape is really quite bendable, so this makes sense. I'll try it out and see how it goes on my next bagging session. Yeah, this was just meant as a low end instructable for smaller projects, I liked reading about your bike fairing project. What kind of speeds are your riders clocking?
Slow :p<br/><br/>~30mph -- but we weigh way too much (~90lbs total vehicle weight) and our fairing has way too much structure to it :p This year's goal is sub 50 pounds - so a 12-15 pound fairing is about where we want to be.<br/><br/>The irony is - that fairing was made on a &quot;low end&quot; budget - for a fairing :p<br/><hr/>Oh,<br/><br/><a rel="nofollow" href="http://www.uscomposites.com">US Composites</a> is another good supplier (we use them and fiberglast) :)<br/>
One Word, and One Word only: monocoque!!!! US Composites is a good reference, I'll include them in the Summary.

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