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Discussion Starter · #1 ·
Adding the 71358199 Helical filler kit into my P1 R70. Hoping to get the straw to flow a little better. Existing helicals are shimmed 1/4 inch, so I will have to to the same to these transitition pieces.
So the question is: (and it is the most basic of rotary Gleaner modification questions) how do you turn a piece of flat bar steel into a perfectly twisted and formed shim? I imagine a hammer, a torch, an anvil, some clamps and a bunch of patience is required. Any hints to ease the process would be greatly appreciated. Thanks.
 

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Use one of your existing shims as a pattern and / or a helical as the pattern for the shim to fit and nest under.

Find a steel wheel or tank or drum or large steel pipe of sufficiently large diameter or something similar of a smooth large diameter to act as a radius bend "former",
The radius bend "former" should be quite a bit smaller in diameter than the curve of an existing shim when the shim is laid straight around the diameter, not at an angle as it is when installed.

Don't worry about the twist at this stage.

The new steel shim with some extra length for purchase, which will be cut off later to the right length, can be tack welded or firmly fastened on one end to the radius "former" and the strip bent smoothly around the "former".
Use a length of pipe or good fitting RHS over the end of the strip to get the necessary purchase and control when bending the strip around the "former".
Although with only 1/4" thick x say 1" steel bar, you don't really need much in the way of extra leverage if any, as it is easy stuff to work by hand when it is as light as that.

Some extra length of the steel bar for each shim is needed for the anchorage or fastening on one end and for leverage purchase on the other end so don't cut yourself short.
The anchored end will not be a smooth curve for the first few inches either so again make allowance in your length of steel strip for each shim for these factors.

[ The shim will only be cut to the correct length when the bend and twist is right, when the bolt holes are drilled and it is seen to nest under a helical OK .]

The strip will spring back somewhat to a larger radius after bending which is why you use a considerably smaller diameter radius "former" than one that matches the curve or bend of the shims.
If the curve is too tight it is very easy to tap the bend out of it with a hammer but very hard to smoothly tighten the curve or bend in the steel shim.
Using a radius "former" like this gives a good smooth bend but at the expense of a few inches of steel that will have to be cut off the ends of the smooth curved section when the shim is finished.

[ I have bent 1/4" by up to 6" wide flat steel bar into smooth curves of over 180 degrees and a diameter of as little as about 9 inches using this technique.
Some heat is necessary with steel flat as heavy or heavier than that.
One example was to take a bad bend / dent out of a combine unloader auger tube without removing the auger tube by making two 6" wide [ correction! ] pieces bent and curved to the same radius as the tube and each covering about 90 degrees of the tube circumference.
They were welded to the base and the screw of an old vehicle screw jack, pushed into the tube to where the damage was and using a long handle, the jack was screwed out, pushing the badly damaged section back into shape until it was barely noticeable ]

Now fasten one end of the new curved shim into the vice, I find vertical is best as you can judge the twist a lot better to match the original, and using a shifter spanner [ shifter "wrench" I think it is for you guys! ] to hold the steel and get the leverage on the other end of the required length of the shim, carefully twist the entire strip along it's length in the right direction until it matches the curve and twist required.
When twisting the strip, hold the spanner so that the spanner just rotates on the spot and the twisting is done right down along the centre axis of the strip.
Don't just grab it and twist as it will bend the strip and be anything but the nice twist you want.

Once the twist is right any fine tuning of the curve can be done with a hammer or the vice and a bit of pipe or RHS for leverage.
Get that twist right as unlike the curve, it can't be easily changed other than by holding one end in the vice and using the shifter to twist or untwist it.
As the shim strip is twisted it will also attempt to straighten some more.

You will probably take a couple of goes before you get the technique right but it is quite easy to do and you are right about some patience being required.
And you shouldn't need any heat or anything special other than that darn radius former , the right diameter of which can be hard to find on a farm plus maybe a welder to anchor the steel ends to the radius "former" if you can't clamp firmly clamp or fasten the end some way.

Mark and drill the holes in the shim after the shim is fitted to the helical as the holes will be in slightly different positions due to the curve and twist and less radius of the helical.

A 1/4" x 1" or 1. 1/4"steel strip will bed down under a helical OK even with small imperfections.
 

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Discussion Starter · #3 ·
ROM - thank you so much for your detailed response. I appreciate very much your wisdom and the time you took to answer my question. Have a great day.

Off to the shop to make it happen!!
 

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Rseventyone last year we put 1/4 in. shims under all of the helicals in a R7. Guess we are lazier than Rom we used 2 pieces of 1/8 X 1 clamped and spot welded to center of helical than used clamps to pull into shape and spot welded ends and drilled holes.You will need die grinder as holes do not line up well. If you are using crome helical probably could not weld. Was long hard job but sure helped green stem beans go thru better. dfb
 

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Got a chuckle out of that, dfb.

The following comes from another Gleaner hotrodder which I used with very good success.
The N7 was a dog in green and tough material with lots of HP used and a thresher that sounded like it was nearly going to come out of the cage with the frightening banging and rumbling.

Strips of 3 mm thick steel about a 1/2" wider than the [ solid ] helicals were made using the above method.
The helical was offset to one side of the shim so that the extra width of the shim strips was on the live side, the side where the material slid along on the helical.
This gave a smooth corner on the live side of the [ solid ] helical for the green and tough material to slide smoothly along and not be held by the cage holes against the side of the helical.

A huge reduction in HP resulted plus a dramatic reduction in rumbling, greater capacity and less loss as the material was no longer bunching up and holding grain against the helicals but could move fast and be separated through the cage holes.
This mod as only done in the thresher section
 
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