Best Hinge Slotter?

Hi all. I'm getting ready to start building the TT Imagine 50 ARF, and it's the first ARF I've run into where the hinge slots weren't pre-cut.

I went to the LHS to look at the Great Planes Slot Machine, but by the time I bought the center line market and the cutting guide for the Slot Machine, I was going to be at $35 or so. I went with the Dubro hinge slotter tool set for $8.25 instead, which included the center line marking jig with the tools:

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Do you folks with years of building experience have a preference for how you cut your hinge slots? I've heard the GP Slot Machine is nice, but it just seemed like a lot of money. Will I be happy with the Dubro hand tools, or should I exchange them and pony up the difference for the Slot Machine?

As always, I'm doubt-filled and angst-ridden as I try to further my building skills.

Ed

Reply to
Ed Paasch
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Yes. I have a #11 Xacto blade that I ground a tiny bit away on the back near the tip so I have the sharp edge and right behind that, there is a recess. I lay the stab and elevator on top each other and mark where the hinges will be and how wide. Then I try to slice and stab the center of that thickness with the blade without piercing flesh. After I get it where I want it, I turn the blade handle around and use the little hook part to pull out enough material that the hinge will slip in without making the balsa spread. I test fit the hinges and surfaces and then remove the hinges and cover both. I then re-slot the covering material and slide the hinges in. But I don't use hinges like that. I put a 45 degree bevel on the bottom edge of the stab and cover both surfaces. Then I cut a strip of the same material, lay the surface down on a flat surface with the hinging edges together and the top surfaces up. Then I lay that strip over that seam and heat bond it down. Then I flip the elevator over the stab so the top surfaces are in contact. I cut another strip to put over the edge of the two surfaces and heat bond that. If this is tight, I cut little slits in some of it at the hinge to free it up. If the elevator is not even with the stab, I just run the iron down the edge while flexing the surfaces and that will free them. You are welcome -- and I didn't mean to confuse you.

Ken

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Reply to
Ken Cashion

Just to add to your doubt and angst, I always cut hinge slots by hand with a No 11 blade. Done it on quite a few models now and it works. Marking the centreline is easy and sure doesn't need a gauge.

Doesn't cost more than a new blade now and then as well >:-)

Reg

Reply to
tux_powered

I bought the hinge slotter and it never worked right for me. Now i use hinge points and have never had a problem with them. And i find them easier to install.

Reply to
max

Ted shuffled out of his cave and grunted these great (and sometimes not so great) words of knowledge:

I have the corded Great Planes Slot Machine. It is sitting gathering dust.

1st, I can not get it to cut a slot in anything but balsa (and the balsa needs to be soft balsa - not over 8 - 9 lb balsa ).

2nd, I find it more trouble than it is worth.

Unless you are going to be cutting A LOT of hinge slots, save your money.

I cut my slots with a good old fashioned #11 blade. I can cut them almost as quickly as with the machine. I have 2 handles. One has a regular #11 blade in it. The other has a #11 blade that I bent the tip slightly - I use this for pulling the wood out of the slot.

Reply to
Ted Campanelli

The cheap way works fine.

Reply to
zara

Ed,

I have the Du-Bro set and use it all the time. It didn't feel "convenient" at first, but after using it a few times, I've come to like it. I mark where the hinge needs to go, pop on the centering jig, work in the correct-sized "fork" tool, then dig out the stuff with the little "digging tool."

One thing to look out for: my "fork" tools have tips that are either very slightly bent at the very end or tips that are not ground square, causing them to cut to one side when I plunge them in. I did a little touch-up work on the them with a stone and now they cut straight.

Good flying, desmobob

Reply to
desmobob

Another hinge material that takes a very narrow slot are 1/2" strips cut from old computer disks, just take one apart and use the inside disk, cut slot with #11 and insert, then a drop of CA and you are in business. I have not used this technique on large models but it works great on small electrics. Have not been able to pull or break a one of these hinges yet.

Red S.

Reply to
Red Scholefield

From the responses it looks like I'm in the minority, but I've had the corded GP Slot Machine for about two years now and I think it is a great tool if you build often. I will admit thought that there is definitely a learning curve to using it - and the guide mechanism is pretty worthless. I cut my slots freehand with the tool, and the trick I use is to tip the machine 30-45 degrees and get a corner of blades into the material first, and then rock the tool back to vertical once the corner is in and grabbing. If you try to bring the blades straight down onto the material they will buck all over the place. Just my $0.02, but I have used the Du-Bro sets and no. 11 blades in the past and I find it much easier to consistently place well formed hinge slots right where I want them with the Slot Machine. By the way, the device only comes with one set of blades and those are for CA hinges. There is another set of blades with slightly more pitch to the teeth for pinned hinges and if you use those hinges (I do) getting the right blades is a big deal. You can kinda wallow it with the narrow blades, but you loose the nice snug fit.

Reply to
Tom Simes

Ed, Use the Great Planes Slot Machine pretty much all the time for the last couple years and it works great. The guide is not a must but it can make things easier. Instead of the guide, I usually use one of the little center line scoring tools before to make a bit of dent to help the blade drop into the groove to get a good start. It certainly makes hinge cuts quickly. Takes a little getting used to in order to avoid it "getting away" but you quickly adapt and then you can cut all the hinges on a model in about 10 minutes! If you enjoy doing it by hand then by all means have fun. It was never my favorite job and this has minimized it. I'm not rich by any means but I do have around 10 airplanes, most of which are flyable at the moment so I can't get to worried about spending $35 on a useful tool... the investment is relatively minimal by comparison to everything else I've spent money on in this hobby and this part of the investment never leaves the ground so is at very little risk.

Jack

Reply to
Jack Sallade

My preference would be to have the butler cut my hinge slots but, alas, I cannot afford a butler so I use a Goldberg centerline marker and #11 x-acto blades.

Texas Pete

Reply to
Texas Pete

Then after a hinge failure crash, you can always fall back on "The butler did it."

Reply to
David Hopper

Yep Ken, I've been using that method (2nd) for years and never had a failure on any size model. The hinge line is invisible from the top and there is absolutely no hinge gap. I try to work it so the sticky side of the top and bottom films are bonded together right at the hinge line. Result = perfect invisible, almost frictionless hinge. I've never flow a model long enough to test it's vulnerability to UV :)

Reply to
Ed Forsythe

Well, I have...on several models. It is a poor flyer who doesn't at least once every five years or so, inspects his hinges and fittings. Just about the time the flex of the hinge is gone and the brittle is starting to show, for some reason, it gets easier to pull the old off...and it doesn't take much heat. On a couple of models, if the original strips are still stuck down good, I slit through the hinge all but a couple of tiny places so it will be held in place and put a new strip (less wide) over that slit. Then I flip it over and put the hinge strip on the bottom but this time, since all of this is attached to the model, I remove the horn and work with mostly the tip of my iron. I am hurt. No one asked me why I put the bevel on the stab rather than the elevator. Generally, it is shown to be on the elevator. I bevel the fin for the rudder and fin hinge joint, as well. Oh..come on...play fair...ask me why I do that.

Ken

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Reply to
Ken Cashion

Considering that most crashes are big mysteries, that is a very funny answer.

Ken

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Reply to
Ken Cashion

Why do you do that? mk

Reply to
MK

Finally! It is always shown to put the bevel on the bottom of the elevator...where there is less structure and where I want to attach a control horn. We need all the material we can get under the control horn and that bevel interferes with where some of the little screws go that hold on the horn...and the backing plate. And that is why. Whew! I feel so much better now.

Ken

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Reply to
Ken Cashion

Point well taken. I just installed horns that has 2 screws on the front of the horn(1 in back). Plane wants 45 Deg. throws and the bevel is in the screw holes.

BTW, I use the electric hinge slotter and I like it but it can be a PITA. You are going to use a #11 anyway.(got to be one of the best tools!) mk

Reply to
MK

Sounds good, Ken...

But aerodynamics indicate the square edge be at the back of the stab to promote a more laminar flow and less passage of air thru the hinge line.... This holds true for our models, also, albeit to a lesser degree. This is why "sealing th' gap" is so effective on our models...

Best to bevel the stab. Harden the horn area with CA to eliminate the "crush" tendency, or install a ply hard point on which to install the horns...

Cheers,

Bill

Reply to
Bill Fulmer

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