Compliance Reduction

The problem that I am having with my MiniLathe is that the support of the cutting tool is too compliant. It is really disconcerting when a cut-off blade dives under the workpiece. Chatter is a problem with all types of cutting tools.

I believe that most of the compliance is in the compound slide. I have worked with lapping the dovetail and adjusting the gib, but cannot get satisfactory performance. When I have to part off, I would much rather use my Sherline lathe.
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My solution is to remove the compound whenever possible. Here are two fixtures that allow just that.

The first one carries a 3/8 inch diameter round carbide insert. I designed it especially for finishing the inside surfaces of a reel spool.
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The insert support is 5/16 inch wide so there is clearance on the sides and the front of the insert and I can use it on all interior surfaces.

The other fixture is just a spacer that replaces the compound.
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Having lost the compound leadscrew, I rely on a dial indicator for axial position.
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There is a problem here, of course. I cannot make fine adjustments and close the half nuts to lock the carriage axially. This is OK for some operations but allows carriage creep for others. So I still need to make a positive carriage lock.

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Posted in Fixtures, Turning | Leave a comment

Cutting a Steep Taper

I want to make a special brass washer, flat on one side and conical on the other. The stock is 7/16 inch diameter brass, and the cone angle is 60 degrees from parallel to the stock rod axis.
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It is easy to set up the Sherline lathe for the conical cut, just pull the alignment key from the bottom of the headstock and rotate the headstock CCW by 30 degrees. The cut can then be made by advancing the cross slide leadscrew. When tapers are less than 45 degrees, you advance the axial leadscrew.

I have seen headstock rotation only on small lathes like Sherline and Taig. The motor mounts to the headstock and rotates with it. Motors for larger lathes are generally too heavy for this, so tapers are made with a compound slide.

So let us see how hard it is to set up this cut with a compound slide. I bought a Chinese minilathe, and am trying to learn how to use it.
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Just turning the compound 30 degrees CW from axial doesn’t work; advancing the compound would just charge the cutter straight into the material, 90 degrees from the desired travel direction.

So let’s rotate on around to 120 degrees CW from axial.
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Direction is good, but I can’t push the apron assembly far enough toward the headstock to bring the cutter into position.

Instead, trying turning the compound 60 degrees CCW from axial.
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Again, direction is good. But I have to run the compound far back to access the screws that lock angular motion, and then I can’t turn the compound crank because it is up against the chip shield.

Final answer: turn the compound 60 degrees CW from axial, and make the cut on the back edge of the part.
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Of course, the bit has to be turned upside down, and stacked on top of another bit to put the cutting edge at correct height.

A conventional lathe with compound slide doesn’t have to be this clumsy. Some have compound angle locks that are more readily accessible, and few have chip shields that get in the way.

I am impressed with the simplicity and ease of use of Sherline’s configuration, and would like to see it available on a larger lathe. This might be possible if the headstock was a spindle motor with a suitably large spindle.

Posted in Turning | 4 Comments

Leo’s Reels

Leo is good at English composition (as well as many other things) so I will just post his Email as sent.

“Hi Dave
My name is Leo, I’m from Germany, been fly fishing for the second year now. Last fall, I built my first rod, and since I am a hobby machinist for the past fifteen years, I just couldn’t live with a store-bought reel on a homemade rod. So I built a reel, and that’s when the mania started. Your website/blog has been a great help in the process, that’s why I wanted to thank you for all the effort you put into documenting your machining, anodizing and designing and improving of your reels.
So far I have made six reels, the first three have a click drag similar to the design of Ralf Vosseler’s reels. The drag on reel number three is adjustable. Number four and five, the black S-Handle reels, have a click drag which I copied from a Scandinavian guy whose name I forgot. Number six has a click drag of your design and I am happy to tell you that it has the smoothest action and nicest sound of all my reels, so I will continue to work with this style of click drag. Reel number six was also the first one that I anodized and colored. Again, thank you so much for the great content on your blog regarding this subject.
So far I am making those reels just for myself, each accompanied by a suitable rod.
In this e-mail I will include a few photos of my reels. And if you search on YouTube for my channel (“Fusselkopp”), you can watch three videos of the making of reel number three.
With best regards from Germany, keep up the great work!
Leo”
Leo5

Leo6

Leo4

Leo3

Leo1

After seeing this, I pushed him to send some more details:

“Well, so here it is.
Reel No.1 to No.3 have the same mechanism, two hollow pins with springs from a disposable cigarette lighter inside them. The pointed ends of the pins engage on a wheel with detents on the back side. This wheel is press-fit onto a hollow shaft, which rides on the center shaft of the reel. The spools themselves have one-way-bearings pressed into the center which ride on the hollow shaft. This lets the spool engage the drag shaft/wheel when line is pulled from the reel, whilst it runs freely as you wind the line back in.
Reel No.3 has an adjustable drag. To achieve this, the described hollow pins and their springs are housed inside a cup, which the drag-adjust-knob presses against, as you tighten or loosen it. This system works well, but it is fiddly to install, the non-hardened pins and wheel are a little prone to wear and the one-way bearing, hollow shaft and wheel amount to some weight. Also the pins demand quite a lot of space in the axial direction, making it slightly difficult to design a slim frame.
Reel No.4 was inspired by your work, but built mostly from stock that was on hand at the moment, so the dimensions came together on the go.
The right side spool end (Delrin) plate has a lip around the outside with teeth are milled into. These teeth are engaged by a pawl (Delrin), which rides in a slot in the right-side end plate of the reel. The pawl is, again, actuated by a spring from a cigarette lighter. this system works really well, but also demands some space. The drag resistance is the same in both wind & unwind direction.
Reel No.5 is just the upscaled version of No.4, with the exception of the slot for the pawl being milled off-center, so the drag resistance in the unwind direction is much greater than when winding in.
Reel No.6 is pretty much modeled after your designs, so I don´t need to go into detail on the click mechanism. I´ll just say it works (and sounds) great, takes up little space and the resistance when pulling out line is noticeably stronger than when winding in.
This reel was also my first attempt at anodizing and coloring, and I am really happy with the results.

Reel No.1:
70mm OD, 33mm overall width, WF4F plus some backing, weight is around 140g
The design was a bit of an experiment, looked better in my head than in real life, but works.

Reel No.2:
65mm OD, 28mm overall width, WF4F plus a minute amount of backing, around 95g
no.2_2

Reel No.3:
78mm OD, 49mm overall width(drag knob sticks out quite a bit), WF7SI and some backing, around 180g
no.3_3

no.3-2

Reel No.4.
77mm OD, 40mm overall width, WF4f and an insane amount of Backing, don´t remember the weight.
no.4_1

no.4_3

Reel No.5:
95mm OD, 45mm overall width, WF8F spey line(double-handed rod) plus some backing, never weighed. Feels heavy, but still a bit too light to balance a 12´6″ rod.

Reel No.6:
75mm OD, 30mm width, WF3F plus a good amount of backing, also around 95g”
no.6_2

group-photo

Here is a link to Leo’s first video on making reel 3:  Part 1  I found it quite entertaining. Links to the other two parts will appear when you watch this.

Posted in Uncategorized | 6 Comments

Gerrit’s Vise

In addition to making reels, I have dabbled with rod ferrules and reel seat hardware. Gerrit (The Netherlands) has found yet another project for the home shop machinist, fly tying vises. This is a beautiful design and execution.
Gerrits Vise
I wonder how he did the curved beam.

Posted in Work Holding | 3 Comments

One Piece Spool, Again

This post is not so much about how to make a one piece spool (topic covered June 2013) as it is about a comparison of two types of metal lathe available to hobbyists.

I now have both a MiniLathe (China source) and a Sherline lathe (California). You would think that just one lathe would be enough to make a simple thing like a fly reel. And indeed, over the course of several years I figured out how to do all the necessary turning operations using the Sherline lathe. (One key development was special jaws for the “3 inch” chuck, May 2015.) When I bought the MiniLathe, my vision was to do all operations with it while taking advantage of its greater weight and torque. But the need for the Sherline lathe has not yet disappeared.

The outside surfaces of the spool are no special problem, it is turning the inside that requires special tools. I made one turning tool for the MiniLathe (April 13, 2017) but it has a large overhang from the toolpost and tends to chatter. So to get the needed stiffness at the cutting edge, I made a special tool that supports the carbide cutter by a solid column of steel all the way down to the cross slide.
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The cutter here is a round RCMT type. It can finish all the interior surfaces.

This new tool displaces the compound slide. With the compound gone, I have to rely on a dial indicator for axial motions.
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This spool is nearly finished. The interior was first roughed out using a vertical mill and a rotary table (supported by a right angle bracket).

I have a similar cutter for the Sherline lathe. But with the MiniLathe I have much more torque (quite noticeable at low speed) and can take a bigger bite. The job is done quicker.

Part of the trouble with the Sherline spindle drive is its “open loop” speed control.  It only sets an armature voltage and cannot sense when the spindle is about to stall. Stall torque decreases as the armature heats up. My MiniLathe has brushless DC drive, which inherently senses speed as part of the commutation logic. Speed is directly regulated, which is quite  different thing from armature voltage regulation.

While turning, the spool in supported by a simple mandrel held in an ER32 collet. Also shown here are aluminum spacer plates.
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When I am done with the special cutter, I still need to put a small radius on the inside of the spool flanges. I do this by first cutting a 45 degree chamfer, and the finishing with a file.
IMG_5384
With the MiniLathe there seems to be no way to bring a cutting tool to the rim of the 2.5 inch diameter flange, when the compound is set at 45 degrees. The cross slide does not have enough range. I could retract the compound further, but then run out of carriage travel towards the headstock.

So, back to the Sherline to cut the chamfers.
IMG_5385
Why is this little lathe so capable? I think that the rotatable headstock is an important feature. It does things that are impossible with a compound slide. Just wish it had better torque at low speed, bigger spindle through hole, etc.

Posted in Spool, Turning | Leave a comment

Fitting Reel Foot to Seat II

This post is additional material to my post of 15 June 2015. In that post, I did not say enough about the interface of the reel foot and the reel seat sliding ring. Here again I am discussing “cap and ring” type seats. These problems do not occur with screw locks seats, in my experience.

A discussion on The Classic Fly Rod Forum, “Nice fish make my reel fall off” http://classicflyrodforum.com/forum/viewtopic.php?f=93&t=81255, addresses the problem. I replied, saying that the radius on the top of the foot should closely match the inner radius of the ring. The reply following mine was probably closer to the target, pointing out that the ring should be as compliant as possible; i.e., deform with a low spring rate. A compliant ring is less likely to loosen from shock and vibration.

I want to point out that the relative compliance of the ring has a lot to do with the radius of the top of the foot. If the foot top radius is larger than the inner radius of the ring, then the ring is loaded at three points.
Ring B
Ring D
In the lower sketch, the load at the bottom of the ring is contact with the reel seat insert.
But when the foot top radius is less than the ring inner radius, the ring is loaded at two diametrically opposite points:
Ring A
Ring C
In this latter case, the ring is much more compliant, and therefore better able to hold when subject to shock.

It should also be apparent from the sketches that contact stress between the ring and foot is much less in the latter situation. So the foot is less likely to be scarred by contact with the ring.

A more recent discussion on the forum is “How do you make your reel feet?” http://classicflyrodforum.com/forum/viewtopic.php?f=93&t=27895 . Several replies show fixtures that are simple straight, cylindical rods. Such a rod will be 0.70 inch diameter in order to fit the foot bottom. When the top surface is turned, the top radius of the foot will be about 0.39 inch out at the tip, and will increase toward the foot center to about 0.50 inch (the foot top is a portion of a cone). Rings that I have seen are in the range of 0.67 to 0.73 inch inner diameter, and so fit such a foot poorly, causing three point contact between ring and foot and damaging the foot.

It is possible to turn the foot top radius so that it is 0.35 inch radius (or even less) over its entire length, but this requires a more complex fixture (see my blog post of 24 July 2016, “A Foot Fixture for the Lathe”.)
IMG_5152

I still own a few commercially made reels, and they have different foot top shapes. My Orvis reel has a foot top that is conical, and is greater than 0.35 inch radius everywhere. It fits both ring and cap poorly and is damaged by contact with a sliding ring.
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My Sage reel has a foot top that is 0.35 inch over its entire length (is cylindrical in shape). It fits both ring and cap nicely and there is no significant damage to the foot.
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Cool Air

We moved to New Mexico last November, and up until a month ago the climate seemed quite pleasant. But June and July here means daily highs of 95 to 100F, and I found that too warm for working in my garage. (Fortunately the overnight lows are about 60F so there is a good time in the day to take a walk.) I could have pumped in house air because the HVAC unit is located in the garage, but garages have big doors that open periodically and that seemed to me a waste of refrigerated air.
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So I have bought a “swamp cooler” and it seems to be quite effective. Keeps the garage about 15F below the outside temperature. It sits in front of an open side door so that it has a good supply of dry air to humidify.

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