Replacement suggestions for plastic arch?

[myxpykalix]

Well my plastic arch bit it the other day and I can't afford E-chain right now so i wondered what other designs anyone is using?

[CNYDWW]

I've been working on an idea for an e-chain assembly made out of 3/16 hardboard with nylon strap sandwiched in between. Giving it a 30deg bevel with an 1/8" gap on the topside of the nylon strap, depending on strap thickness should allow it to bend properly. 1/2" plywood and most likely dowels to retain the wires on the chain. Another thought was basically attaching with a couple small screws and washers, a piece of roller chain.

[srwtlc]

Jack,

If you're talking about the older black ones, I have one left over from when I ordered some several years ago. Don't need it anymore, cost of shipping and it's yours. ;)

At the time, I thought about making a hinged bent lamination, but found a local place that had sheets of the stuff and just bought a few strips.

[dmidkiff]

Jack you can sandwich the broken area between .25" plywood to get by. I could not afford the e-chain and made my own based on something that Poco had posted sometime back. Not sure of the link, but I used plastic laminate (formica) and plywood. I had scrapes of plywood and made them into about 4" squares on table saw. I then cut small circles in the center of the square and then ripped them in half on table saw. I then screwed the plywood to the laminate and placed the cables in as I went. It has worked great and the only problem that I have had is the plywood is not holding the screws where the stress is higher. If I were to do it again I would use solid wood.

[gc3]

Well my plastic arch bit it the other day and I can't afford E-chain right now so i wondered what other designs anyone is using?

http://shop.ebay.com/i.html?_from=R40&_trksid=p5197.m570.l1313&_nkw=cable+carrier&_sacat=See-All-Categories

a few choices. i got 12' of 3" for $75...

[curtiss]

not quite e chain but

http://www.talkshopbot.com/forum/showthread.php?t=511&highlight=v-chain

[beacon14]

After duct-taping the old arch together (worked great, for a while), I made mine out of scraps of plywood and some 1/8" polyethylene that was left over from another project. I did have to buy another bag of nylon zip ties, cost me about $7 if I remember correctly and I still have 900 ties left over.

[dhunt]

After a few breakages and patchings
then using 1/4 in. flexi-ply (no longer avail. on the island)
we made a new arch/bow from a piece of straight-grain ASH
of purty much the same dimensions as the bow we were supplied
and so far it's been working OK!
It's flexing very well, even when scrunched up out at the extreme end of Y movement
which we don't do very often, admittedly..


I suspect the new Ash bow been working well because we also made a spare
whose edges have been rounded-over to allow smoother passing of the nearby dust tube
- and because we have the spare all ready to go
the first one now will not break ever, but you know how that goes.. :D


Having spares works, although not always in the way you thought it would...

[srwtlc]

All that humidity can't hurt either! ;)

[dhunt]

All that humidity can't hurt either! ;)No no!
Our Shopbot PRT-96 lives and works in an air-conditioned room!

[myxpykalix]

Scott send me your email address so i can make arrangements with you....
THANKS!

[srwtlc]

Okiday, sent.

[john_hartman]

Jack- I have my original arch from a PRS Alpha. Its yours if you want it...

[geneb]

I like the idea of using the e-chain, but I'm concerned about introducing noise into the stepper cabling from the spindle drive & power cable. Is that a serious concern?

g.

[bleeth]

Been using it for years. I simply made sure my spindle cable and others weren't wrpped with each other and haven't had an issue. All the big iron machines use it and they tend to have a bit more power running through their cables than we do.

[steelcnccutter]

check out this cable holder. maybe this would work for you. looks easy to build.
http://www.youtube.com/watch?v=5SS8aT-D-IQ

[Chuck Keysor]

Jack, as I recall, you have the same size PRTalpha as me, 5 feet by 12 feet. Two weeks ago, as I was continuing to slowly reassemble my machine. I got to the plastic arch, and found it wouldn't clear my low basement ceiling. So I called Shopbot and ordered an echain. They said they didn't have the kit for my old machine, just the chain. But since I only wanted the chain, that was fine.

They sent me "Echain Y60 +SR FA/MI 30 links" which cost $71.44 before shipping. Shipping was $16. I made the bracket myself from materials I had on hand, so this is pretty cheap. (Note though, the fit was a bit tight, and so I wish I would have gotten another two links.)

When I bought my used Shopbot, the original plastic arch had snapped in the center. It had been repaired by putting a hinge in the middle. It looked a little cheap, but the guy I bought it from said it worked fine.

Chuck