FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:48:23 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:48:46 GMT -5
I'm going to focus on the offset part to start with, I'll work the rest out as I go along... Started by cutting it up: I'm going to use a couple more of my 8" x 8" x 1/2" plates for the hinge. (originally purchased the plates for gate-post bases) Here's a rough drawing of how I'm thinking about doing it: I'm thinking about using either 1" mild steel round bar, or a section of a car axle for the pivot pin...
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:49:10 GMT -5
My mission for today was to drill the plates and arm for the pivot pin... Started by making a pizza box template to confirm the measurements I had in my head were correct, and allowed enough clearance for the arm to swing: I measured the car axle, it was 1.293" diameter, so I use a 32mm (1 1/4") hole saw... The hole saw holes are usually a little over-sized so I thought it should be fairly close to a snug fit. Started with the 8x8 plates: BTW: I got sick of my little baby drill-press when I was building the log splitter so I purchased a second hand 3/4hp Taiwanese 5/8" #2morse taper drill press.... It cost me about 1/2 of what a new Chinese one would have cost The only thing it lacks is a rotary table, but I can live with that. This chart: www.fairburyfastener.com/holesaw_speed_chart.htm said I should use 275rpm for a 1 1/4" hole in mild steel ... As usual I used lots of water to help clear the chips and cool the holesaw... The holes were 0.5mm (0.0200") too small to fit over the axle so I attacked the holes with a die grinder and a 1" drum? sander, (basically just cleaned the holes up) Now they fit
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:49:34 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:49:54 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:50:48 GMT -5
I purchased a Canadian made "John Deere 4 inch bore x 8 inch stroke" tie-rod style cylinder cheap on ebay a couple of months ago that I'll use for the swing-offset... The link from the top of the 3ph to beam at the back is a T shape about 1/4" thick.I haven't decided what I'm using for the diagnal brace yet... maybe a bit of square tube or one of the lamp-post arm (like used on my log splitter) .. lol I only had a chance to do about an hour work on it today... Cut and drilled the bits that'll be welded inside the boom to reinforce the pivot: I'll add a grease nipple (zerk) to the tube tomorrow and weld it all in
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:51:17 GMT -5
I made a rough carboard 1/10th scale model so I could check out the angles and measure how far out past the wheels it'll swing... Also checking how far I can swing it left and right without it being possible to drive the blade into the rear tires (lol, the rear tires are in the bottom corners ) It's a crude way to work things out, but it's quick and helpfull
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:51:50 GMT -5
This pic shows the size of the pipe I've welded into the boom: Clamped the pivot point reinforcing bits into the boom and welded them together: Welded a piece of 4" x 1/4" inside the boom near where the front edge of the hinge is, so the boom doesn't get deformed: Drilled and tapped the tube for a 6mm grease nipple, then welded it into the boom: Drilled a 5/8" hole in the side of the boom for easy access to the grease nipple: Welded a 4" x 1/4" cap on the end of the boom so it doesn't get crushed: Welded a small 2" x 1/2" brace to the top of the hinge: I couldn't find a bit of pipe that was a snug fit over the top section of the axle for the diagonal brace, it's 28mm (about 1 1/8") ... so I ended up having to use a bit of 1 1/4" OD galv water pipe that was a bit too small.... Spent ages working on it with the die grinder and file until it fitted.... I had to open it up about 1mm (about 3/64") .....(A lathe is at the top of my wish list!!!) I'll finish the diagonal brace and top mounts tomorrow
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:53:55 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:55:10 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:55:33 GMT -5
Here's a 20 second (1meg) video of 30* each way:(Sorry it's so dark) (as usual it's best to click the "Full Size" link up the top left)
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:56:00 GMT -5
Rob: send me some dimensions and I will draw it on CAD for you.A CAD drawing would be appreciated, but please don't put other things on hold to do it.. If you don't have time that's no problem (I don't want to inconvenience you) Thanks (I think I've got most the dimensions on there) Today I'll re-install the blade to see how far past the tires it goes at the current 30* offset, and exactly how much further it will go if I increase it to 45*... (I quite like the cylinder at the side, it's out of the way and keeps all the forces horizontal)... If I do any real work today I might move onto fixing up the blade mounts...
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:57:23 GMT -5
From Rob:
Well, This is all I could get done tonight. First I picked a point off the side of the boom near the blade at a nominal distance. Then I kicked the blade over at 45° each way and I drew the radius of the hydraulic cylinders closed and extended from that point off the boom. Where they intersect is where the connecting point must be at the anchor pivot. In this case, it is off to the left of the 8" square plates, so you will need to weld a bracket to both the boom and those plates. At least this is where the point is for the nominal dimensions I picked out. The points are the small red circles.
Here are the hydraulic cylinders shown at those points and swung each way 45°. The left swing is full retracted and the right swing is fully extended.
I will draw more tomorrow to see if the angle between the blade pivot point and the hydraulic cylinder connection points is great enough not to cause a problem when the blade is straight back. I think it's OK, but I have not rotated it at 10° increments to be sure. Perhaps Matt, you can locate the pivot points where they are drawn and try it out with air like you did previously? Let me know, OK? Rob-
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:58:10 GMT -5
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FLICK
CTW Expert
DF-354
Posts: 201
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Post by FLICK on Feb 1, 2008 4:58:55 GMT -5
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