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I need the skinny on air vacuum pumps. I'll be gluing on a bridge where I won't have access through the sound hole (sound hole in upper bout) so was planning on using the bridge vacuum jig that Bob Garrish made for me. Harbor Freight has an air vacuum pump which achieves 29" of vacuum for sale for about $14 (same as on Amazon for $32). Is this going to do the job for me or will I have to go to a more expensive venturi a la LMI?

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A higher purpose for wood.
Rich Smith
Issaquah, WA

Harbor Freight carries mostly junk. And you almost always get what you pay for. If you are looking using vacuum clamping - check out Joe Woodworker's website and build one of those systems yourself. You will end up with something that is much more useful and higher quality. If you are doing a Venturi system, make sure to use as big a storage tank (for the vacuum) as possible.

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Simon

I built the Joe Woodworker one and love it.

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Andy Z.
http://www.lazydogguitars.com

Ummm...that statement only carries weight if you've actually used it. Granted, I make no claims that HF is top-of-the-line stuff, but a venturi is extremely simple and there's not a heck of a lot you can screw up. No moving parts, nothing. I have NOT used one, but at the price I wouldn't be afraid to try it.

Here's the simple math - LMI's venturi setup is $152.10, HF's is $12.99 (I assume the refrigerant vacuum pump is the one you mean, since you said the venturi type). I see the air consumption is about double the LMI unit at 4.2 CFM @ 90 PSI, but most compressors won't have a problem with that.

I know nothing about the Joe Woodworker version, but I know several folks use and love it. Personally, if I was ready to go vacuum, I wouldn't be afraid to spend $13.

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Wes McMillian
Santo, TX
http://www.wesmcmillian.com

I always felt LMI's venturi pump was a overpriced. I used it on maybe half a dozen guitars before the noise of having the compressor cycling nonstop for about 30-40 minutes drove me insane. As said the technology behind it is ridiculously simple so for $13 it's at least worth a try... but I'd recommend against spending $150 on the LMI unit.

I built the Joe Woodworker vacuum pump and it's great. It's quiet (depending on the type of pump you use), efficient and the storage tanks gives them a much more consistent vacuum -- I found that the venturi would fluctuate pretty significantly with the cycling of the compressor.

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Richard
http://www.guitarmaker.com

Wes, no offense intended. I have a local Harbor Freight and have visited several times. Everything I have bought there I have regretted buying. I would rather have put the money to use for something of higher quality. I am not saying that the things they carry aren't useful - but in comparison to what the market offers, their quality level is at the very bottom. Sometimes that wouldn't be much of an issue but when it comes to how I build guitars and especially considering how quality affects the useful life of a tool in the long run, I generally like to use equipment that is at least average in quality.

Granted, a venturi system is simple but so are screws. Have you ever used cheap screws that snap off at the heads with the least amount of force? Also $13 bucks is $13 bucks that could go towards the purchase of the nicer system. IN other words, just a different mentality. And in my personal experience, going the cheapest route usually comes back to bite you in the end. Hence, my recommendation.

The item I'm talking about is not actually a Harbor Freight product - they just carry it. Here it is on Amazon at a much higher price: http://www.amazon.com/Advanced-Design-A ... 972&sr=8-1

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A higher purpose for wood.
Rich Smith
Issaquah, WA

I have one I got Joe Woodworker. A ready built one. Those cheap ones won't generate the necessary force to clamp down a bridge nor will they last if used continuously...

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Peter M.
Cornerstone Guitars
http://www.cornerstoneukes.com

Hee, hee, no problem Simon. Not like I'm the Defender of All Things Harbor Freight or anything...

Again, I've never used a vacuum rig for luthierie so take that into consideration. I say if you're adventurous, spend the $13 and maybe save yourself loads of money. To play it safe, I'd do the Joe Woodworker thing that's so highly regarded and probably never regret the spending the money on a quality product. Me, when I decide to go that route I'll probably try the venturi first. I may regret it. Also bear in mind that I have a large 60 gallon upright compressor in my shop.

HF does have some pure junk. They also have some awesome bargains on some pretty good tools if you're selective.

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Wes McMillian
Santo, TX
http://www.wesmcmillian.com

I have the LMI pump setup and works great and don't have to build anything. Hook up the hose to the pump and the clamp, plug it in and little later unplug it and your bridge is stuck on the top tight. Maybe you need continues running of the pump, and all the stuff the rig Joe has. Each shop has it's own needs. I don't so go simple with it. I do vacuum for bracing and same thing. Use the Bob Garrish clamp for the bridge, bridge plate and all other braces. Again just have right size hose, fixtures for the attaching hose to clamps, plug in and 15 to 30 minute later unplug. I will usually go about 10 minutes turn off, clean glue up and then plug back in until get back to it. My LMI rig went down and I used a HF pump until replaced the other and now have two so most times I can do two things at same time. Haven't seen any difference. Heck I even used those Chicago(sp) lam trimmers on about 40 binding jobs and no problem and cheap to replace. Good tools are great, but if can't afford or not want to spend money on everything can do good with less expensive stuff. Like John M said in another thread as has the boss, lot of times it isn't the name on the machine or tool, but technique.

...and you're basing this on what? Right now I've got a basic Venturi for my compressor (from Vac-U-Clamp), and it draws more than enough vacuum (although the compressor cycles on and off for about 30 seconds ever 2-3 minutes) to hold a guitar body very, very steady indeed in my binding jig (Williams/Fleishmann style). The device is really very simple, so I'm not sure what parts would 'wear out', even if used to glue down a bridge. My dad and I tried pulling a scrap off of the vacuum clamped piece, and it wasn't going anywhere. No budging at all.

The main issue I have with the thing is that it's noise, and due to the size of the compressor, not very portable, which is why I'm looking at either building a JWW type unit or simply getting a dedicated vacuum pump. If I can find one cheap-ish locally, that is.