Vodkaman

Vman rocking beam duplicator

41 posts in this topic

Here are some pics of the Vman rocking beam duplicator. Pic1 shows the master with the dummy cutter follower, pic2 shows the cutter end, pic3 shows the result with another that I cleaned up with a flap wheel on the drill press.

I am satisfied with this first attempt, but there are problems. The main problem, which I did foresee, but did nothing about, was spindle alignment. This is critical in order to achieve a one to one copy, the slightest error and you create a different shape.

Spindle alignment is impossible when hand making such a unit from ply wood, but there are solutions. I overcame the problem with floating bearing plates (on the far side, not visible). These are bolted in position, once everything is aligned.

For the mark 1 effort, I decided to make the machine a hand crank, but it can be driven by a motor.

For mark 1, I chose a plunge router cut. The advantage of this, is that there is no bounce and the follower can be set very light, which reduces wear on the master.

There are several disadvantages though. As you can see, the cutter ridges require a bit of cleaning up, but this only takes a minute or so with a flap wheel. The main disadvantage was that progress was slow. I was reluctant to push the feed, as you have to listen to what the machine is telling you. The cutter bit was not new, but seemed fairly sharp. I think this is mainly because the machine is cutting end grain, never a good thing. If I allowed the cutter to follow the 6mm dia spindle, the block would snap, so I had to start the nose with a larger diameter than I would have liked.

However, I have designed the machine so that can easily be adapted to other cutter methods, such as turning the router through 90 deg and

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Dave,

This may not mean much but I'm impressed. I could not build that machine with you reading step by step instructions. I will have to stick with the old hand carving method.

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Cool tool Dave. Nice craftsmanship. Have no doubt you will come up with solutions for the issues you mentioned in your post. :yay:

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Vary nice Dave looks like a good one . Any chance of getting video on the operation. I do better with moving visuels. (is that spelled right?) I want the plans if there is any. Frank

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Looks to me if you reduced the stock size it would help with the feed. Seems the height could be reduced significantly. If the bait is being cut in one pass, perhaps leaning the cutter in the direction of travel could help also. As far as cleaning up the bait tumbling with an abrasive has been known to work well in the past

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Thanks for the nice comments.

KC, you are absolutely right. After a night playing pool and consuming alcohol, my mind never left the project. I occured to me that I am cutting far too much wood.

Reducing the stock wood to the parameters of the master would vastly reduce the load on the cutter. This just needs more accuracy in locating the stock. Not a dificult problem to overcome.

The part is cut in one pass. Pointless in making two passes, as the cutter would follow the same path. Also, the cut can be done in both directions, without breaking the rules of routering.

Turning the router cutter through 90 degrees, as suggested in my previous post, would not solve the problem of the end grain, but it would minimise the ridges. I am leaning towards the idea of using the angle grinder method, first shown by Redg8r. The advantage of this is 40 cuts per revolution compared with two cuts of the router bit, a significant advantage in tool wear. Also the cost of a router bit is seven times more than a saw blade with theoretically, 20 times less wear with the saw cutter.

KC, the tumbling abrasive system, which we have discussed before, is a serious consideration, which will be explored, should I solve all the innitial duplicator problems.

My next tast is a total re-design and re-build, carrying foreward much knowledge acquired from the Mk1.

Frank, I am reluctant to put a video out until I solve the problems, same goes for plans. The last thing I want to do is inflict a migrane on my friends. This is a first draft, not a solution.

Dave

Edited by Vodkaman

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A design out of the norm Dave. To be LaPicky, your stylus and cutter are traveling in an arc (longer and longer arm will reduce the arc to a manageable "straight" line); but I do foresee problem with cutting speed this way. The slight arc will introduce different cutting depth along the front and tail end. It could introduce binding of the cutter bit as it attempts to cut deeper and the head and tail end. Would be more obvious if it's a longer lure or if you are to cut a series of lures lined up (say 3 or 4 lures in a row). JMHO

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V-Man, you've been busy! :yay:Nice machine for a starter. I am sure that you will be able to solve the problems that you spoke of.:? Good luck with this project. Can't wait to see your next one.

John

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Thanks LP, I try to be different.

Regarding the arc, my thoughts are that both the stylus and the cutter are making the same arc, so duplication occurs. The radius of the arc is 277mm, so over the travel of the cutter, it is almost straight, 0.4mm from straight over 15mm depth. Not sure I understand the binding, but it could be part of the problem.

Sinyo. The problem with small lure bodies is the diameter of the spindle holding the master. On the Mk1, I used 6mm, but this snapped at the router end, with the light wood that I used (albasia density 0.35gm/cm3). On the Mk2, I intend increasing the spindle diameter to 8mm. This is still OK on 3" lures, but much smaller and there will be nothing left to duplicate.

KC, I did a run with the stock trimmed down. A dramatic improvement in cutter load and speed. Pretty obvious really, duh!

The main problem that I am having now, is the spring loaded spike plates, holding the stock. About one in three, the stock cuts loose. So I am now working on a new stock clamping system. A pity really, as the spring loaded clamp was quick and efficient to operate.

Dave

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Brilliant! A truly ingenious machine.

If you can, cutting from the center toward eash end might reduce the tearout.

And that would let you go deeper on the head end, so there is less left to hand shape.

Also, if you hit the blank with a quick drying sanding sealer, or any clear lacquer, after it's roughed out, but before you take it off, to lock the wood fibers, and then pass over it again with the router, you might get smoother results on the second pass.

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Thanks Mark. Seems like a reasonable suggestion, but it would not solve the ridges, as the end of the cutter is sharp/flat. Maybe a round nose cutter would improve things. I will try to locate one on my next shopping expedition.

I have come up with a design for the stock clamp. I think it might just solve all the problems. start building it tomorrow.

Dave

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Dave - I am up in Queensland so I don't have access to my pictures BUT I had the same problem with the cutter when I was making 2" blanks years back.

I was always going to go to a half round bit at the smallest diameter possible for your blank, but never had the money to buy one - I think a half round with 3 or 4 cutting edges (not 2) and made of carbon steel (not tungsten) as they are much sharper. Also if you can't get carbon steel cutters, you can sharpen the tungsten bits with a honing stone, honing along the flat (not the beveled cutting edge). I think I have mentioned before the Russian guy who used a saw blade with extreme angles on the cutting teeth, this was supposed to work well @ about 2.500 - 3,000 RPM - but this would not fit a router???

Love the 'Rocking Beam Duplicator", the thing that stands out for me is it is exactly the same as your original drawings, something I can never achieve - Rock On Baby..pete

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I agree with Pete I think you need a ball end mill. they are used for metal working but are really slick for wood. Is your router set up with a fixed size collet or is it ajustable? I use an 1/8"(3mm) four flute carbide bit to mill out the hinge area for my swim baits. These only cost about 8 dollars US . I would tell you how long they last but I am still using the first one. Also on these bits I turn them about 4000 rpm really slow for a router. I tried to get a link for these but the web site is to confusing. ENCO, MSC, RUTLAND TOOLS or any machine tool supply house. These come really sharp when you gut them and cut like butter. If you try these I think the ridges will be smoother.

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Frank and Pete, I agree, this may be the way to go. Unfortunately, my router is fixed collet (1/2") and fixed speed (mega fast). I will see what is available. But what ever cutter is chosen, it will have to do the entire job, changing cutters is not an option.

The length of the cutter is important, it has to extend about 50mm past the router mounting structure as this structure has to clear the stock clamps. This is why I chose a 1/2" dia cutter. I feel a smaller diameter cutter of this length would introduce chatter or tool bounce, could even snap under the load.

I built the new stock clamp today. A vast improvement in performance. No breakouts of the stock and I was able to machine the stock thinner at each end, so I will probably stay with the 6mm spindle. However, the clamping process is very cumbersome and time consuming, with eight screws. I now have a better design in my head, that should be even more secure with only two screws. Better still if I can find a supply of wing bolts.

Timing is 7 minutes per blank, this includes loading and unloading. With the new design of clamp, I should be able to reduce this by a couple of minutes. Actual routering of the profile is only about 90 seconds, the rest of the time is making the initial cut into the stock, which has to be done with care.

Dave

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MSC Google Search Results Ck this one out not a bad price but there is many out there. As for the speed you can get a router speed control so you can slow the rougter. Just a thought. I want to see it work.

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Hi Vman,

I was wandering what your engineering mind worked on lately, and here it is, nice job, my boxes full of machines are jealous on your workshop :lol: maybe we'll have a chat in the chatroom like in old times ;)

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Haven't been around much lately have been starting a new business. That tends to consume every last desire. But I get on about once a week to check things out and I see this. Good job v-man. I feel a rounder cutter would make less work in the end. But not a completely round one. Just rounded edges. The tip you have could be honed down to a slight rounded cutting edge. Probably app. 1/16 of an inch (I know our stinken inch not metric) rounded on the edge to match up with the previous cut. If you made a tool with wood to hold the bit, the angle would match on both sides. I would think you have a stone for sharpening your knives. There is a bit that looks like a porky pine that might cut a little rounder. Some thing that would be fun would be to add a flat guide instead of a round one. Then add a third axis so it tips back and forth with the length of the bait? But still limit the movement so it would not tip over. That way a flat cutter would follow the contour of the bait. Come to think of it that would not work on your design because they are followed on opposite angles but it would work it they were on the same plane. (following the same angle) I left this just for ideas.

On the clamping of the cutting peace I think stay simple and cut a peace of plywood in the shape of a square c then cut a peace that is the exact size of the in side of the c. Put a hinge on the two peaces to make a door. The out side can be screwed in place after it is aliened the in side would hold the blank guide in place. Then make a door lock similar to the ones you see on a enclosed work trailer. That way you grab a blank set in there and when you close the (door) it will lock it in place. Speeding up the reloads. We both know the point of it is faster is better.

By the way did you add counter weight to the guide end or is all the router weight on the master?

I also think you should leave the router going as fast as possible. Slowing down would add chatter.

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Kelly, thanks for all the input and feedback.

I managed to purchase a full round cutter, but it is a 12mm collet, so now I need to find a collet.

I take your point with the rounding of an existing cutter. I have a few old cutters, I could give that a try. I have a couple of stones for sharpening the plane m/c blades, be they seem a bit too fine for this job. My next tool purchase will be a grinder, but not even sure about this use, could be dangerous! I have never used one.

You are correct about the stock clamp, I started to get really complex with it. I viewed Jerry's machine again last night, such a simple spring loaded affair. Thinking about it, the stock was kicking out, because it was just too large for the body size I was cutting, also, on the original spring loaded spike plate, the spikes were too close to the edge of the stock.

So I am re-visiting the spike plate and using an idea similar to yours, by adding a top and side plate, for support ('L' as opposed to your 'C' suggestion). This will help to locate the trimmed down stock in the correct place. Also the two spike plates can be opposed at each end of the stock. I will keep your suggestion ready if this one should fail.

As for the counter balance (you are on the ball!), I have used two plastic bottles, partially filled with water, hanging beneath the stylus end. This arrangement is easy to 'tune' the pressure on the cutter and the stylus. If you view the second picture in post #20 http://www.tackleunderground.com/forum/hard-baits/13966-wokshops-2.html you can see the machine behind the router table, with the bottles hanging.

I did not want to get involved with speed adjustment, so the thing is turning at 23,000 rpm. With the reduced stock, this seems to be working just fine.

Once again, good input, thanks.

Dave

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Unable to purchase a 12mm collet at this time, I have modified the duplicator to accept an angle grinder, fitted with a standard 4

Edited by Vodkaman

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V-man your saw blade is cutting perfectly straight leaving the tooth marks but if you tip the grinder 15 or 20 degrees it will be cutting on an angle not leaving the groove in the middle of the blade. That should leave a rounder cut not the 60 deg. angle of the teeth. The one thing is you would need to experiment on the angle to get the cut to disappear. But that is your specialty.

The grinder route is the same I followed. Have all my parts sitting weighting for me. I think when I have time I will go with something similar to Jerry's idea With the tipping board. What are the RPM your grinder is running at? Just double check the blade tolerance.

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Advantages:

The first cut of the slender saw cutter is effortless compared with the bulky router cutter, which has to be eased into the wood.

No tearing or fluffing up of the grain as given by the router, as the saw cut is in a different direction. The saw cutter is perpendicular to the wood, whereas the router cut tends to give varying tangential cuts on certain parts of the body, requiring more work to clean up.

A better finish is achieved, again because of the direction of the cut, also 40 cuts per revolution of the saw cutter compared with 2 cuts per revolution of the router bit. 8000 cutting strokes per second compared with 766 cutting strokes per second of the router.

The finer cuts place less load on the stock and so no failures due to the stock kicking from the cutter. This enabled me to greatly simplify the stock clamps, enabling faster loading.

Agreed :yes:

Disadvantages:

The cutter marks/ridges are prominent, as with end milling, but I consider this acceptable for the moment.

Yep, my issue was limitations from using stock blades, most are ATB (Alternate Bevel tooth) Combo, or flat tooth. I spoke with a local sharpener about having the teeth sharpened like the 3rd tooth on a triple chip blade:

like so: >>> /

Have not done it yet, but that should lessen the spiral grooves left by conventional blades.

Scary machinery, safety procedures are essential. I need to do more work on Mk2 to improve user protection.

The 4

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