Ken, I think I see the magnet you've got, is it item number CA41LWH?
If so, they don't list a price. I asked for a quote. I know prices change, but about how much each in quantity? I'd probably order about 150 to start with, but I don't know how much they are...

2slow2matter,
If you follow the link off of airfield models to the magnet source they have a page set up just for this. Here is the link [link]http://www.magnetsource.com/airfieldmodels/[/link] For 150 they are 55¢ each. The prices and stock # are listed on the link I just posted. When I called to order I talked to the guy for a bit as he got ready to place the order. I ordered 250 at the time and he went ahead and gave me the price break as if I ordered 500, which was 46¢ each. Since he did that I was able to afford a few more so I ordered 300.

Hope this helps

Ken

That helps a ton. Good gosh, if you put four of those on each fixture, you'd have a total of 48 lbs of pulling force? How do you pull those off without tearing up the fixtures?

im glad i started this.....its a good discusion to get going

You don't pull them off directly. You tilt them to one side and then lift them up.

Ken

so ken is 300 all you needed to use, or did you end up needing more?

I've done 2 builds with 300, and I'm currently doing the LT-40 with that many. It's actually plenty. I build extra fixtures above what Paul recommends, but other than that 300 is plenty.

Ken

One thing to note on this system. The magnets do start to lose their effectiveness after a few years. I think that can be avoided somewhat if the magnets are stored on a metal plate with the same side down or something like that. Honestly I don't know how it works, but I did read something somewhere that explained why magnets lose their pull and how to avoid it.

I use so many magnets with my system that it's not worth the trouble of figuring out which end is up. I bought 500 magnets earlier this summer to replace mine and just bought another 500 for fixtures that I build for folks.

It is an excellent system. I've been using it for about 5 years now and still love it.

BTW - the magnets from the magnet source are the exact same as the ones in the GP system. The difference is that GP charges a lot more for them.

CafeenMan,
Great!!! Here's the man himself. The one that got it started for me. Thanks for stepping in to answer some of the questions.

Ken

you know you cna get a magnet recharger right. We had a few of them in the chem lab for a while

Does it work for LiPo magnets?

How much is a charger vs. $0.46 ea. for magnets?

dunno ill talk to mom and see if she has any of her classroom supply catalogs left. Ill also drop a line to my chem prof while im going...

Howdy Ken!

I took a long sebatical (sp?) this summer. My computer burst into flames and I built a new one which runs circles around my old one. So I spent those month playing all the games I have that lagged too much on my old system. Half Life 2 consumes a lot of time!

Then the fan on my new processor died and I couldn't keep my computer running for more than 20 minutes before it would overheat and shut down. I've got all that fixed now and I'm back working on the SR Eindecker I started last Spring. Just put on the last clear coats, so all that's left to do is glue hinges, final assembly and attaching pull-pulls. SR says "2 weeks of leisurely evenings." Umm... ok.

Magnet "rechargers" are just very strong magnets themselves that are used to re-polarize the magnets. They work well on some magnets, and not real well on others. The cheapest ones use permanent magnets, and run between 50 and 100 dollars. The BEST ones are electromagnets and run over 150 dollars, I believe (it's been a while since I've ordered one). Not worth it for a .46 Magnet!!

Well, it might be worth it if I'm shelling out $250.00 for 500 magnets every couple years. But that would depend on how well it works and how long it takes. If I have to spend more than 10 seconds per magnet it's not worth it.

I don't even want to go there. My wife keeps asking me if I'm ready to upgrade my computer, but I tell her I'm not ready. Because if I upgrade then I can run Half Life 2, and rig th now I definitely don't want that. I don't have the time to spare on that. It's almost embarrassing what my computer is. But you know what they say about the mechanics car!!! The computer tech's home computer is always barely running. Actually, for what I do it's actually still a great system. It's only a PIII 1 Ghz system, but it's got 3 GB of memory onboard and about 800 GB worth of network storage space. It gets done most of what I need it to.

Ken

The magnets that I'd recharge would take overnight. You could possible get 5 or 6 of these latch magnets on one recharger at a time. You decide...

ummm... mine was a PII 450 that I built in 1998. I'm going to put DOS back on it so I can play some of my old games.

When I do get a new system, the one I have now will get loaded with Linux, have a bunch of hard drive space crammed in it, and added to the server storage farm!!!!!

Ken

Hmm, so these magnets are 12 lb pull force. Has that been pretty reasonable, or would more or less pull force make sense? I've been pondering doing something like this, but I keep looking at those magnets and thinking they seem awfully bulky. Been pondering Neodymium magnets, because you can get some pretty small magnets that have good pull forces. Course, then I'd have to figure out where to put the setup, since my last plane I built on the kitchen island. (Needless to say, my wife was a BIG fan of that.) Although a smaller setup similar to what I used might let me build on the island, and move it out of the way as necessary.

one nice thing about a board like this, it could be done as a modular table(ie multiple units you could add as time went by)

I've got a lot of those little Neodymium magnets that I use. You really need the latch magnets both to make the fixtures and for basic building. The square shape of them let you use them to butt up against parts. And you really need all 4 latch magnets on a fixture in order to hold in place. Trust me on this one. The little Neodymium magnets are great for holding the plans secure on the steel sheet.

Ken

Hey Ken, in the fourth pic you posted above, I see some magnets (being used on the wing ribs) that are sitting on, or attached to what looks small pieces of 90 deg. angled steel. What exactly are those made of, and are the magnets attached, or just being used to secure them?

Lowlevlflyer,
Those are actually a building aid that I made for when I was still using pins to build with. I took a piece of 1" extruded aluminum that I picked up at Lowe's. I cut them into 1" pieces for this use. For using pins I drilled a hole on one side of the bracket to pin it down with. When I converted to magnets I put some adhesive magnetic strips on the bottom of the bracket but it doesn't have enough "grab" to stay in place. So I use 2 magnets on each bracket to hold them down for this build. Once important thing is that after you cut the 1" pieces it's a good idea to check each bracket with a square to ensure that it's still at 90°. The biggest place I use these is for holding ribs in place while building the wing. Take a look at these pictures and let me know if you have any questions.

Ken

When using the vertical presses, I often use more than a pair of magnets at the front of the fixture. You'd be surprised how easily the magnets will pull from the board when using the presses. I have a "Monster" fixture with 6 magnets (2 pairs of 3) mounted at the front and it still comes off the board before I want it to!