# Question on NH 488 crimping roller settings



## ZekeTheDog (Apr 26, 2010)

I don't think my crimp rollers in the haybine are doing the duty properly... last year it seems it crimped the crop better than this year. I bought it used and it was in good shape.

I'm not sure how much wear is on the rollers and I read the manual and studied the machine. The cranks seem to work a torsion bar to add pressure, but there's no way it seems to adjust the pinch gap which looks too wide to me. I see shims on the roller glide rests on the each side of the unit where about a .75x.75 square block rests. The shim packs are held by a carriage bolt and nut. It looks like you remove the carriage bolts and take the weight off the rollers to get the shims out... Am I close??

I have the cranks tight as can be and I can't find any marks on the crop like they're being squeezed at all and the dry time seems long, like it's just sickle bar cut and the conditioner gap is set too high and the crop just goes through.

My questions are:

What should be the gap between the lands of the rollers?
Is the gap set by removing the shims? (manual offers no clues)
How to tell the amount of wear on the rollers?
(I see that the ridges look squarer at the edges of the roller. Was that the original shape.)
Where does the actual crimping take place? On just the corners of the currugations? or on the entire area?

I hope I made myself clear. It's late and I'm exhausted...Thanks for your replies.

N Chester County PA.
NH 488 haybine
Pequea 9 ft rotary rake
Hayliner 68 baler


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## ZekeTheDog (Apr 26, 2010)

Oh, BTW, another question is where to measure the gap between the rolls of the 488.

By just eyeballing it looking through the gap, I'd say the gap is 3/16" to 1/4" (.0188 to .25) right now between the lands. I haven't measured the actual gap or the gap at the corners to know.

thanks.


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## Haymike56 (May 3, 2010)

I don't have the book in front of me so this is just from memory. I believe the gap should be either 1/32" or 3/32" at the closest point across the rollers. The book talks about how the stems should look after being crimped. They should be cracked aproximately every 2", they dont actually get crushed. You are correct about removing the shims to adjust the clearance if the machine has some age on it i have seen where pack rust will build up on the shimms and increase your space. Just remove the shims and the rust and reassemble setting the gap at the same time. You won't see too much wear on the rollers, at least not here in the Midwest, more so with age you will find cracking and cuts in the rubber. i have tried glueing these but to no avail. when they get bad enough that they start comming apart it is time to replace them.
I just tried something with mine, based on what circle C says on thier site about running the rolls in full contact and with extra pressure. I adjusted the clearance to 0" but not touching. When you adjust them you have to roll them by hand and check the clearance in a few spots acroos the width. I then cranked the pressure way up. After this was done I ran the unit and checked for scuffing on the rolls. Since doing this I have cut about 30 acres and the Alalpha seemed to be crushed the full length and yet the leaves were still attached. Good luck with your season ours is off to a WET start this year


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## ZekeTheDog (Apr 26, 2010)

Thanks for that... I did find that they recommended 1/32-1/16. I'm way wider than that. I do have just a couple dings on the rollers (stones most likely) I was thinking of trying to open the crack slightly and using a super strong epoxy to keep the moisture out of it.

The unit has no rust on it and I can see the shim packs and carriage bolts ok. In fact, the factory paint is still excellent and might make the nut removal more difficult. It was kept indoors until me - it won't fit through my 12' doors.

Is there a trick to getting the pressure off the wear plate to remove the shims easily??
( I can't get it into my shop to use the hoist, so any ideas of what to do or even NOT do would be helpful!)

Thanks.


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## sedurbin (May 30, 2009)

Zeke, A good and accurate way to check the roll gap is to roll up some aluminum foil and run it through the rollers, by hand. The rollers will crush the foil and you will be able to measure the thickness with a mic. or calipers.


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## mlappin (Jun 25, 2009)

Take a tire iron and place it between the rolls from the backside close to one end, then place a large wrench on a shaft and rotate it backwards. The tire iron will spread the rolls making the shims a piece of cake to change. I always adjusted mine as close as possible until they jsut touched, then measured the thickness of the shims, and rearranged them until I added a few thousands from the original measurement. I've made my own as well if the stock ones weren't the right thickness. Remember...the closer you can run them, the better. The aftermarket rollers like Circle C run together even as tight as you can apply pressure.


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## Haymike56 (May 3, 2010)

The last time I did it I used a 4' bar and had a neighbor pry them apart while I took out the shims. Have the bolt out and ready to remove them before they pry them apart and for gods sake keep you hands clear of that area cause if they slip with the bar GOTCHA! Good luck.


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## ZekeTheDog (Apr 26, 2010)

I liked the tire iron idea...and the aluminum foil.

I plan to take the foil and measure the current gap on each end. Then subtract the shims that leave a 1/16" gap.

Thanks a lot guys. I'll let you know how that goes if my health holds.


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