Enclosed Track Bit???

[ajwaverider]

Maybe you posted the original question in two different threads? I always wonder about that. You can end up with some answers in one thread and some in another, and they are not coordinated.

I noticed that at the beginning and it's happen more than once.Maybe a tech problem in the software/server.

If you look at around the shaft you can see the porosity in it .Maybe they fill them and sand down the track.

[ame="http://www.spearboard.com/showthread.php?t=17639"]Spearboard Spearfishing Community[/ame]

 

[Bill McIntyre]

I noticed that at the beginning and it's happen more than once.Maybe a tech problem in the software/server.

http://www.spearboard.com/showthread.php?t=17639

I've always assumed that the person posting just wanted to put it in more than one place to make sure he got responses from those who only look at certain forums. But you end up with a mess. I see the same question from the same person in more than one forum, and I have to make a choice of forums for my reply. I don't think most of us are willing to place the same reply in multiple forums.

 

[ajwaverider]

OK guys...looks like some of it was moved to another thread...

http://forums.deeperblue.net/showthread.php?t=60961

Not sure why...but at least the info is still there. It seems as if there are two duplicate directories/categories:

Hunting Equipment>DIY/Homemade
Hunting Equipment>spearguns and accessories>homemade equipment

One or the other should probably be removed and have one directory that is listed as a subheading to each of the categories. That way it is accessible through either avenue, if it is posted on one it shows up on the other as well.

That's what I was talking about .It's happened before and I don't think it's done by the poster but by the site.If you post a thread in the sub-forum it puts the same post in the main forum.So it makes two post out of one original .

 

[miles]

Hiya

I've merged the two threads, so all the information is available in ONE easy to read thread!!

Sorry for the inconveniance!!

Regards
miles

 

[ajwaverider]

Thanks Miles.

 

[defofthecrown]

As far as pouring a track goes I hace a few suggestions that might mitgate the bubbles in the final product. First, mix a small batch of epoxy and cover the surface of the grove in the wood. This will 'seal' the wood and prevent bubbles from off gassing into the final pour.

For the 'track' portion use the slowest curing epoxy you can find. Mix it w/ something called a squirrel mixer. This will mix the reagents w/out add bubbles into the liquid product. The best way to avoid them is preventative mixing, not getting rid of them after the fact. Be especially careful when adding the graphite powder to sprinkle it on the surface and mix it in slowly, not trapping and infusing pockets of air.

Keep the whole thing very warm as Sven said this is the only proper way to thin epoxy and this will improve its qualities while appplying it. The problem is heat also severly limits your working time-which is why slow cure is the way to go.

When pouring the track add the epoxy slowly in one spot, and leet it fill in the track. Don't pour it from directly overhead. Start on one end and let the epoxy flow from the lowest point to the highest, this will help to keep it from trapping air.

 

[defofthecrown]

What I would like to know is how these ttracks hold up w/ the expansion/contraction of the wood. I know the delrin gets minamally pinned but the epoxy would be bonded along the entire length. It's fairly flexible not not in thick pieces. Has any one heard of a gun like this cracking or delaminating?

 

[GilbertG.]

Sven, Chris,

Great tips!! If I only knew then....

Hey where can I get one a dem sqwerly thingies? Sounds like a useful tool. It would sure beat hand mixing.

Gil

 

[icarus pacific]

If I'm thinking of the same mixer, a squirrel mixer resembles the wheel that a hamster runs in inside it's cage. They're available at Home Depots and pretty much have to be at the better paint stores. Chuck it in a drill motor and off you go.

On the durability thing, the couple of tracks I've poured and the few I've seen seem to hold up well. I imagine that the large bonding area provided by the routed groove adds up, and the temperature difference isn't that much where the thing would pop out. I think you could reduce any doubts about the track staying in place by installing a couple of pins into the groove before pouring and letting them do the anchoring.

Mixing graphite is not a lot of fun- it wants to pool at the surface and takes a fairly aggressive folding-in to become uniform. I failed to mention this earlier- when you add a filler to epoxy or any multi-part adhesive, mix the filler with the base first, then add and mix the catalyst/hardener. Let sit for a couple and then pour away.

 

[defofthecrown]

This is a plastic store near me and they carry small-ish mixers which is nice w/ epoxy. Heres a link so you can see what I'm talking about, http://www.tapplastics.com/shop/product.php?pid=201&