My Edge Bender

For discussions related to designing and making ski/snowboard-building equipment, such as presses, core profilers, edge benders, etc.

Moderators: Head Monkey, kelvin, bigKam, skidesmond, chrismp

skidesmond
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Post by skidesmond »

hafte wrote: Skidesmond, How’s the washer bender doing. I may opt for that. A few $$ for washers is much better on the pocket book.
Hafte
It works pretty good. I haven't tried to incorporate it into a permanent vise yet like twizzstyle. That's on my to-do list. I slide a few teeth in a time and bend it a little at a time and work it until I get a good fit. What was taking a frustrating 10-20 minutes per edge before can be done in a 3-5 minutes. The teeth don't bend out of shape and the twisting of the edge is minimal and can be untwisted easily. Much easier on the fingers and hands.
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redbull
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Post by redbull »

we built our rollers in two pieces for each... so six parts were machined in total.
http://www.skibuilders.com/phpBB2/viewt ... c&start=15
you can't see in the photo, but we press fitted bearings into the rollers (hidden under the washers). twizzstyle, I noticed in your CAD you just have holes for the bolts (no bearings). is there much friction when bending a tight radius... get stuck?
twizzstyle
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Post by twizzstyle »

No friction at all. I have the bolts just tight enough so that there is no up/down play, but not so tight as to keep the rollers from spinning. I put locktight on the bolts so they won't back themselves out. The rollers spin totally freely.

I think another big difference is it looks like your center roller only has the slit for the edge teeth, where as mine I have the entire edge going into the roller. I don't think it makes any difference in the outcome though.
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threeninethree
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Post by threeninethree »

Found this site for machining.. http://www.emachineshop.com

You download their cad software, design your part, say what type of material. Then the software analyzes the part and gives you a price. Then the part is shipped to you.

I drafted out one of these rollers (edge teeth roller) done in t6 alum. for 1 roller the cost would be $197, but if 10 were made the total cost would be $278.73. ($27.17 each). Food for thought of the group buy power for these rollers, mold templates ect.
~ Matt
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KevyWevy
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Post by KevyWevy »

threeninethree wrote:Found this site for machining.. http://www.emachineshop.com

You download their cad software, design your part, say what type of material. Then the software analyzes the part and gives you a price. Then the part is shipped to you.

I drafted out one of these rollers (edge teeth roller) done in t6 alum. for 1 roller the cost would be $197, but if 10 were made the total cost would be $278.73. ($27.17 each). Food for thought of the group buy power for these rollers, mold templates ect.

wow thats a fantastic idea.
dbtahoe
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Post by dbtahoe »

twizzstyle wrote:
turn it into a CNC edge bender 8) Maybe that'll be a project for next year, for now I need to hurry up and get some skis made, the snow's already falling!
How about this... Load the edge in the rollers on one side, and load your ski template adjacent. Then as you push the ski through, the main roller turns as well as adjusting the pressure and bends the edge to match the profile.
twizzstyle
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Post by twizzstyle »

dbtahoe wrote:
twizzstyle wrote:
turn it into a CNC edge bender 8) Maybe that'll be a project for next year, for now I need to hurry up and get some skis made, the snow's already falling!
How about this... Load the edge in the rollers on one side, and load your ski template adjacent. Then as you push the ski through, the main roller turns as well as adjusting the pressure and bends the edge to match the profile.
I think I more or less understand what you're getting at. The problem is since the steel isn't heated and its a cold bend, there is some amount of relaxation in the bend. So if you set the rollers to give you an exact radius, once the edge actually comes out the radius is slightly larger (the metal "springs" back a little). So you'd have to account for that somehow.
doughboyshredder
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Post by doughboyshredder »

Image

http://www.doorkingparts.com/DoorKing/D ... wheels.htm

two of the 3" wheels bolted together with a long bolt through my steel table. Makes bending so quick and easy it's ridiculous. Still have to bend it by hand, but the wheel holds the edge and gives it a smooth radius to bend around.

10.00 each for the wheels is retarded cheap. Two of them and a bolt and you got an edge bender.
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falls
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Post by falls »

twizz or red bull: how did you decide how far apart the 2 rollers would be?
The single roller obviously needs to have its centre exactly halfway between the centres of the other two, but is there a reasoning for how far apart you would mount the 2 rollers on their side? thanks
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redbull
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Post by redbull »

I went for mounting the rollers as close together as I could. The further apart the rollers, the more you would have to accommodate for springback. If you put them too close, then the single roller won't be able to get "between" the two rollers for the tighter radii. So figure the tightest radius you'll be bending and go from there to determine where to position the two rollers. Our bender provides with very little springback.
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falls
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Post by falls »

thanks redbull do you design your ski shapes with specific radii in mind. I think I saw on the skevik video you marked the edges where each radius needs to start and stop. Is that from trial and error or from knowing for how far your ski bends at a particular radius?
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redbull
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Post by redbull »

trial and error: first you have to mark the position of the vise where it bends at the correct radius, then figure how long the edge needs to be bent. you might waste a bit of edge but once you have it, you can bang them out.
i guess you could look at your design drawings, but you would probably still have to "calibrate" your bender to figure out the radius positions (to account for any springback).
skidesmond
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Post by skidesmond »

doughboyshredder wrote:Image

http://www.doorkingparts.com/DoorKing/D ... wheels.htm

two of the 3" wheels bolted together with a long bolt through my steel table. Makes bending so quick and easy it's ridiculous. Still have to bend it by hand, but the wheel holds the edge and gives it a smooth radius to bend around.

10.00 each for the wheels is retarded cheap. Two of them and a bolt and you got an edge bender.
Great idea. Gotta love ingenuity!
twizzstyle
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Post by twizzstyle »

Just as Redbull said, the spacing of the rollers just depends on how tight of radius you need to get, etc. I would say the closer you can make them the better, the closer you can keep them the less spring back you'll have, and the better it will keep the edges flat (although if you're rollers are machined precisely enough, that won't matter). I can't remember the spacing on mine, but its probably something like 3 inches center-to-center.

My skis don't have a constant radius tip, I think that makes skis look stubby and a little weird. So unfortunately for me, its not as easy as just passing an edge through the bender at a constant radius, and slapping it on the base. There is a lot of bending, checking, unbending, re-bending, checking, etc. But the beauty is the perfectly smooth curves and completely flat edge. After some practice I can do it pretty quick (on my last pair of skis, first ones with the bender, the first edge probably took me 15 minutes to get it just right... by the time I did the last edge it took me about 2 minutes)
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falls
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Post by falls »

that's pretty speedy work.
I haven't played with any edge material as yet, but it the thing in the back of my mind that is most daunting. I have access to a metal lathe so am looking to make a bender like you guys have to try and make it a bit easier.
Did you use aluminium stock for the rollers? Do you remember which alloy?
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