Bending base with edges

[sammer]

I thought I'd start another thread as I didn't want to highjack Richuks' laser cutting thread for this.

I stopped doing full wrap edges because my vacuum system could not pull the tip and tail down to the mold.
I would have to pre-bend my bases with edges attached.
This led to large amounts of grief as the edges would go out of plain (twist) or would pop off the base.
Not only that but using my hands and a piece of pipe or whatever (nalgene bottle worked the best)

I could never exactly match the radius of the tip/ tail mold.
I know this incorrect radius is what is causing my edge fall on the skis that don't have full wrap edges.

I've been thinking of something like a slip roll for a while now.
The one in my head was built with old wringer washing machine rollers.
Last week Falls posted a pic of a 6" slip roll and a light went on in my head
I had no idea small slip rolls existed. I had only seen huge ones.
So that got me thinking, if I was to buy one of these could it be modified to fit base and edge?
Anybody seen one of these 12" slip rolls in real life?



Would this be easy? Just a matter of adjustment?
They are designed for 22 gauge sheet metal, which is roughly .75mm.

Would I have to have one or two of the rollers machined to a smaller diameter?

Any input much appreciated.

sam

[twizzstyle]

I've been promising Richuk a picture of my tip bender for a couple of weeks, but I keep flaking. I'll do my best to take a picture this afternoon.

It's basically a 5" steel drum, with a 2" roller and a handle. Does exactly what you're talking about, I got the idea from a Poor Boyz intro from I think the K2 factory. I made it out of scrap metal I had lying around, you could make it out of wood even.

[Richuk]

Yeah, yeah, that's right ... made it out of scrape metal and I have to pay for mine. Rub it in

The guy at G W Models is going to roll a sample (plastic with edges), so hopefully you'll be able to gauge the performance Sam.

[Toddh77]

i made mine from 2 wooden rolling pins and bolted them to a box, and simply roll my bases through. It works great. I think i spent $15 to build it. looks a lot like your pic above. I haven't posted before, so i can't put up pics yet. but I'll send one when i am allowed.

[sir.orange]

im using one like this to bend my cassettes and bases with attached edges:

http://tinyurl.com/3lsgqlg

if not glued and pressed on every teeth, the edge pops of sometimes. the 2 adjusting knobs are to lift or deepen the upper roll. the maximum material thickness is 2mm, so edges fit in narrow.
i dont know what the knobs on your photos are for, should work the same way, but im not sure if you ll get a 2mm gap.

[MontuckyMadman]

rolling pins. huh.
We have a slip roller around the corner yeah and its huge.
I would like to have one on site.
How bout this is this a premade edge bender?
http://cgi.ebay.de/Holzmann-Rundbiegema ... 4aad889a68
Hijak.

and this one too.
http://cgi.ebay.de/Walzmaschine-Metallb ... 5d3005ac30

wait heres this one in teh states, a ring roller, huh.
http://www.ebay.com/itm/PLANETARY-RING- ... 20b83cc1e9

[sammer]

montucky; I've already got an edge bender.



and it works great.
But then trying to bend base and edges into mold at tip and tail causes them to twist. or as I said to pop off.
I'm thinking about the rolling pin idea.
3 rolling pins in a box. Only one has to be adjustable, as the thickness of the material getting bent is always the same, to control your arc.
Might need some rubber or grip tape for traction so a crank handle can push/pull the base thru.

Shouldn't be too hard. I'll have to work on this and let you know!

sam

[Richuk]

In light of what orange has said, I wonder whether the action shown in the video is better than the slow processing of the slip roller. I am assuming the heat developed within the edge during the action (slight though it may be) allows the edge follow the form more readily?

The first time I tried this, I didn't bond every tooth ... Orange, your not using ordinary superglue are you?

[sir.orange]

... Orange, your not using ordinary superglue are you?

i am.

the edges of the bases i tried to bend with slip rollers were bend and attached crappy, so they popped of i guess. i ll keep on bending this way but putting more efforts in clean edge fitting and gluing. should work.
my rocker moulds dont have radii, theyre parables, so anyway i ll never get a base fitting 100% to the shape of the mould.
not sure if this is really necessary with pressure 50 psi onwards... theres a bunch of guys out there laying up in flat cassettes, and they produce qualtity that makes them even sell their stuff...

[Richuk]

CA (superglue) is quite brittle, It will crack and I suspect it contributes to delam - as a result of water ingress.

Rubberised CA with a very fine nozzle is available. You can get packs of ten nozzles £1.00.

I looked at something like this too http://www.toolstation.com/shop/Adhesiv ... 340/p47989 , not tried it.

There are other types of resins available ... but you need the right delivery system. I think if you are very careful about where you apply the CA, you can get away with using it and you don't have to get too technical.

[vinman]

Gorilla brand super glue has a rubber component that they say is
More impact resistant. I use it and so far have good results.

For tips/tails I'm gluing each tooth at the very tip for about 5 teeth, then every other tooth to the end of the tip radius. After that ever 3rd along the running length.

I've not done any pretending though but after reading this I'm thinking about it.

[twizzstyle]

I keep getting pulled away from the shop so I've still failed to get photos of my tip roller, but I had a few minutes at work just now so I whipped up some crappy Paint drawings.

I used a section of 5" steel pipe I had lying around for the bending surface. That has a couple pieces of angle iron welded to the sides that get clamped to my work table. Because the angle iron is welded to the pipe itself, it cannot rotate. There is a bar going up on either side that pivots at the center of the 5" pipe, and another bar at the top going laterally acting as a handle. There is a 2" pipe that can spin freely that is up maybe 1/4" from the 5" pipe. The exact gap is NOT important, as long as its larger than the base/edge thickness. You don't need to get a perfect bend here, that's what your mold is for, this just gets you close so you don't have issues once in the mold.

All you do is stick the base and edges between the roller and the 5" drum, rough out where you think the bend should start, then pull the handle around and down to bend it, keep pulling until it passes the tip and it will spring back to a nearly perfect tip.





You could use wood for everything, I just happened to have a bunch of scrap stuff left over from my jet engine project that worked perfect. I'm sure there are many ways of going about this, but I think this is much simpler than a slip roller, and again I'm of the opinion that you don't need to be exact at all here, that's the job of your mold during pressing. This just gets you close so you don't have issues, and it's easier to do the layup in the mold.

You will have to excuse the horrible 3D sketch here



It also seems to me like it would take quite a bit of time with a slip roller. Setting the thickness, then trying to feed the base/edges into the thing, then fiddling with the adjustment, then rolling it, then backing it back out, etc. With the thing I made it's literally a 5 second job. Slide the base in, pull the handle down, done.

Go to 2:15 in this video and you'll see EXACTLY what I am doing.

[MontuckyMadman]

cheaphe slip roller is really easy. As you know you dont need an exact bend. But what about that ring roller does anyone think its a viable edge bender for cheap?
twizz. Thats pretty sweet. I was thinking of the same thing afetr that line vid. I ghing any ski with a tightwr radius tip is gonna be prebent. A longer rocker like iggies it doesnt matter.

[Richuk]

MM ... the reason for pre-forming and pre-bending is to remove the tension from the edge set relative to the template. The press doesn't eliminate this. This is clearly shown every time you use your edge bender - if you cold roll, it doesn't give you the exact radius of the form.

[Brazen]

If you use the rubberized CA it doesn't get chewed away by the epoxy and you will have delam problems down the line. Period.