Jump to content

- - - - -

Metal Tubing Swimbait Hinge

  • Please log in to reply
3 replies to this topic

#1 diemai


    Advanced Member

  • TU Sponsor
  • PipPipPip
  • 2,394 posts
  • Location:
    near Hamburg/Germany

Posted 07 February 2010 - 09:38 AM

Hi , folks ,

Being inspired by TU and by all of the great fella's in here , I've been tinkering with a few swimbait designs during the past months(or even more than a year ?) .

Always on the quest for the possibly easiest , fastest and most reliable way of joining wooden swimbait sections , .......also a lot of ideas were put up in here by other fellow members , ....just a great community :yay: !

Anyway , the last idea posted in here , that I can think of , was utilizing double leader sleeves as a joining part , and that is the basic of the construction , that I have thought of right now .

My idea is to make the joining parts inbetween the single swimbait sections out of round metal tubing , that is simply squeezed flat in a vise , leaving an open sleeve end for the later connecting hinge pin to pass through .

The flat side of the squeezed tubing piece would be epoxied into a centered slot in the male part of the joint , additionally secured by a crosswise wire pin , ......the sleeve end of it would reach into a sufficiently large and wide pouch cut centered into the female portion of the joint .

The required slots and pouches could easily be furnished with a "Dremel" and it's different small drill and router bits .

Like on my previous swimbait(also shown on the picture) I would glue in small Plaster of Paris rivet heads into the hinge pin bores to act as bearings , spacers and seal off against water sepage(check image , I've laid them in about the position they would be glued in later) .

One would have to take care about making the pouches in the female side large enough for the joint to still move freely after topcoating as well .

If the body width of the bait is still thick enough at the female front parts , these pouches would probably not show too much , ......only if the flanks do taper down the tail a kinda gap would probably appear , as the material is not thick enough anmore to cut a "hidden" pouch still providing sufficient sideward play of the joint .

I intend to round off both opposing section ends a bit , so that they are able to pivot against one another without binding , ....maybe it would even be enough to round off only one side .......I shall see ?

On the pictures you can see the original sketch copy of the finished bait already glued on a teakwood kitchen board , I have marked the intended separation lines with a felt marker .

The front hinge piece is made from stainless steel tubing 12mm X 1mm (12millimetres dia. and 1mm wall thickness) , the one in center from 10 X 1 aluminium and the rear piece from 8 x 0,6 brass tubing , ..............these are all tubings , that I could find down the workshop so far !

Just did some testing today to see whether shaping the tubing pieces would cause any difficulties , ...but it really doesn't !

Just cut required length off and squeeze it in a vise to an elongated shape , ........now put a round dowel(drill bit shaft or nail) into one inside end of the oval , leave that end a bit protruding over the vises edge and squeeze real tight finally , .........the dowel inside of the protruding end would keep a sleeve open , you might only have to pull it out with pliers afterwards .

Naturally that dowel has to be a bit thicker than your intended hinge pin diameter , in this case I used a 2 mm bit shaft and I am gonna take 1,5 mm wire pins to connect the lure sections later .

The stainless steel tubing would surely hold up against any fish , but it is real heavy stuff , ........and not easily accessible to me ,...... found a piece accidentally on the scrapyard of my work .

The center aluminium tubing might probably be too weak , as after bending it to shape it is obvious , that the material's structure has already been disturbed at the tightest curves , ........don't trust on it too much !

The brass tubing does not show signs of wear and tear like the aluminium one , but it is too thin , ....I need it with a thicker wall of 1 mm as well , so I guess , that this would be the one to go for , ......it is not quite as heavy as steel and also easy accessible over here ,....... almost every tool mart stocks brass tubing .

Also I think , that I would need a larger tube diameter than just 12 mm , maybe 14 mm or even 16 mm , so that these connecting hinge parts would turn out a little longer , so that they could be anchored a bit more sturdy into the wood .

Well , just my thoughts so far , .........I am quite confident , that this design would work out , ........what do you think about it ????

greetz , diemai :yay:

Attached Files

Edited by diemai, 07 February 2010 - 09:40 AM.

  • masinax5 likes this

#2 jigginpig



  • TU Member
  • PipPip
  • 82 posts
  • Location:
    Corvallis, Oregon

Posted 09 February 2010 - 02:56 AM

I like the idea very much.

In fact, I had a very similar idea for a tail.

the issue I can see for the articulated joint is one of friction.

If the channel for the pin is large enough, there would be less friction, as contact between the two
components of the hinge would be limited to the back of the joint. But the contact would extend vertically,
and so have a large surface area. (this is assuming a good alignment in the joint components is acheived)

the beauty of the screw eye and pin joint is the fact that there is very little friction, due to the fact that there is
limited contact.

The drawback is that it is as ugly as home made soap.

If you are making a bait that is meant for steady retreive, ala Tripple Trout, less friction is a must! Dead stick baits,
or very realistic baits like the Rago Tool or 3:16 wakebaits, require a better looking joint to complete the illusion of
realisism. Of course these high end lures are great swimmers as well, but they look dead nuts when at rest.

Joints are an area of particular interest to the amateur builder, and the more we work on the issue the better we
will be able to ply our craft!

Good work, keep it up.


#3 diemai


    Advanced Member

  • TU Sponsor
  • PipPipPip
  • 2,394 posts
  • Location:
    near Hamburg/Germany

Posted 13 February 2010 - 03:23 PM

@ jigginpig

I see your concerns about friction on the joints , .........but I think , that these Plaster of Paris rivet heads would act as a good bearing surface , because the minor the contact surface , that you've mentioned , quite a bit .

But still I guess , that this tubing construction introduced here would not move as smooth as the finished bait shown does , but maybe still sufficiently frictionless ?

Just oughta try it out , but.... heck , ...I could never find suitable tubing , 12mm dia. is a bit too small , I want 14mm , 15mm or even16mm dia . brass !

I might as well make these connecting parts out of sheet metal , bend in the same manner as shown in my "sheet metal hinges" tutorial , .........the result would be pretty much the same !

But thanks for your input and hints , anyway , ........much appreciated !

greetz , Dieter :yay:

#4 diemai


    Advanced Member

  • TU Sponsor
  • PipPipPip
  • 2,394 posts
  • Location:
    near Hamburg/Germany

Posted 14 February 2010 - 05:14 PM

Took a chance today and put this particular hinge design to a test !

Still could not find suitable tubing , so I just utilized stripes of 0,5 mm stainless steel sheet ,...... the principle remains the same , anyway .

The total swing of all sections scratches 90° like this , still have to take some material away from the male parts to achieve a slightly larger gap , then it should be OK , even after painting and topcoating !

The brass tubings still have to be trimmed to suitable lengths , they act as bearing bushes and to seal off the hinge bores against water sepage .

I will have to epoxy them into the bores caring about accurate fit and location vertically , as they also act as spacers for the hinge sleeve , a vertical bearing surface and also set the proper vertical position of the segments against one another to maintain smooth outline transitions at back and belly .

I will squeeze the bottom ends of the belly tubings closed before glueing them in , ........this way the hinge pin can't slide out at belly side anymore , ...........after the final assembly I would just secure the top end of the hinge pins with a drop of glue , ....leave a small countersunk at the back exit of the hinge pin bores for that purpose .

I will also drill one or two little crosswise holes into the sheet metal connectors , so that the epoxy glue will bond them more reliable into their slots , .....the crosswise wire pins shoud assure the possibly strongest bond .

Hope , that you can figure out by my pictures , ........could not take the 90° total swing of all sections , all parts are still loose , it would have fallen apart on one single improper move !

greetz , diemai :yay:

Attached Files

  • masinax5 likes this