# WHY PINS



## chuckduster01 (May 30, 2015)

Just curious as to why some folks put pins in laminated frames made of wood on wood and wood on phenolic laminations. I have never once used more than Tightbond III on wood and good marine epoxy on phenolics and have yet to have a frame delaminate or come apart. I realize the pins kinda look cool but are they truly needed? Are they only really "needed" on slotted frames or does the aluminum/micarta have some special needs or what...I need some edumacation on this matter. FWIW, no I have never made a micarta on aluminum frame. What am I missing? THANK YOU.


----------



## Abenso (Apr 28, 2017)

I'm not 100% but it has to do with grain movement and temperature fluctuations effects on differing materiels

Sent from my SM-S920L using Tapatalk


----------



## MIsling (Sep 7, 2017)

I am by no means an expert, but I think the main reasons they are used are either looks, or like Abenso said to prevent the scales from shifting do to differing expansion rates of the different materials when they undergo temperature change.

Sent from my VS980 4G using Tapatalk


----------



## Jolly Roger (Aug 14, 2017)

Jim Harris of Performance Catapults pins his custom SPS slingshots. However, he has recently begun making Birch Plywood SPS frames with the standard aluminum cores available. He is making this model to keep the cost down and it sells for a mere $59.99 just one penny short of $60.00. You can find them on eBay under SPS Slingshots. This model unlike the more pricey exotic wood and g10 models is not pinned. If it were necessary to be pinned I am sure he would take the extra time and effort to pin them.

Does using pins merely make cored slingshots look nice and give a reason to double the price of the end product? I doubt that pins alone without glue or epoxy would hold the scales in place. It must be the glue doing the holding things together. Or has someone along the line sold us all on the myth that cored slingshots must be pinned no matter what?


----------



## Ukprelude (Apr 17, 2016)

I think it's just for a bit added security folks use pins esspesialy with metal cores as glue doesn't always take to metal as well as say g10, wood or other materials. I also don't think it's done to add value either. When I think about it, it's probably just the makers preference whether or not they want to use them. Here are 3 of mine (note how the metal core is pinned and the other non metal arnt) 
Great question by the way, I'd like to hear from a maker to see what their view is 























Sent from my SM-G935F using Tapatalk


----------



## flipgun (Nov 14, 2012)

I have used internal pins for materials that I am unfamiliar with. I have used through and through when bonding PVC and HDPE; but more for belt and suspenders security than anything.


----------



## chuckduster01 (May 30, 2015)

Thanks for your thoughts fellas. Much appreciated. Has anyone done actual destructive testing on any of this in the past that I am not aware of by chance?


----------



## mattwalt (Jan 5, 2017)

Same reason people put them in knives...

There are a few various reasons for this - but ultimately its top keep the scales attached in case anything fails.

Ambiant moisture / temperature fluctuations etc. and using materials which undergo different changes as a result (different density woods (or grains running in opposing directions even), plastics which are impervious to moisture. But also teh adhesives used. These days they can be fantastically good - but when you're sticking 2 different types of material together its the only bond - and failures can and do happen.


----------



## Jolly Roger (Aug 14, 2017)

Ooak Forge (yes spelled correctly) sells a nice sized TTF 3/8" aluminum powder coated slingshot. It has a really simple and effective no tie flat band attachment method. When I noticed that the holes in the handle/grip were tapped with threads I traded a local knife maker a few old farrier rasps for putting scales on this red aluminum beauty. He screwed on some really pretty black ebony scales. No messy glue to leak out and mar the red aluminum that shows through between the scales. I wonder why cores aren't tapped so scales can be screwed on like we do with pistol grips.


----------



## mattwalt (Jan 5, 2017)

Hey JR - yeah some guys use this approach (think Metro Grade Goods did a few).

You also can get some cool bolts these days that do the same thing (threaded sleeve that fits in the hole with screws either end). Threading the core does make damaged threads a little bit of a pain to rectify without the tools. Also any play would mean a less than near perfect fit. You can also use both in tandem (bolt & glued) thats actually quite common.

Its all down to what tools are available, skill and approach you're taking.


----------



## jazz (May 15, 2012)

I use pins sometimes (not very often) and this thread forced me to think why; most probably it is for

- security reasons: for example when I glue aluminum to something else I make pin tightly (but not too tightly) sit into the drilled hole and on top of that I put some glue/epoxy into the hole;

- psychological reasons: sometimes even doing what I said above does not make me fully ensured of the integrity of the system so that at least I know that I did my best..

- decorative reasons: sometimes something in the design, material, texture, color, an interesting section etc. simply calls for a pin - you can not help but pin it in..

There is a saying here in Bosnia "when there is a ball let the toilet burn along" so, once I had no good material for pins for a long time and as soon as I got one brass and one aluminum rod from a friend - I made a frame with pins just for the sake of it!

cheers,

jazz


----------



## Abenso (Apr 28, 2017)

jazz said:


> I use pins sometimes (not very often) and this thread forced me to think why; most probably it is for
> 
> - security reasons: for example when I glue aluminum to something else I make pin tightly (but not too tightly) sit into the drilled hole and on top of that I put some glue/epoxy into the hole;
> 
> ...


That is quite a saying. I'm not sure I understand

Sent from my SM-S920L using Tapatalk


----------



## Jolly Roger (Aug 14, 2017)

mattwalt said:


> Hey JR - yeah some guys use this approach (think Metro Grade Goods did a few).
> 
> You also can get some cool bolts these days that do the same thing (threaded sleeve that fits in the hole with screws either end). Threading the core does make damaged threads a little bit of a pain to rectify without the tools. Also any play would mean a less than near perfect fit. You can also use both in tandem (bolt & glued) thats actually quite common.
> 
> Its all down to what tools are available, skill and approach you're taking.


made me think of The Alley Cat. Jack used that method on hiss grips.


----------



## chuckduster01 (May 30, 2015)

I really appreciate everyone's response and explaining this to me, THANK YOU I thought maybe the aluminum played a big factor in this.


----------



## mattwalt (Jan 5, 2017)

Actually Aluminium... you always need to be sure surfaces are clean - oil-free and well keyed - even with pins (no matter what material) when gluing.


----------



## Jolly Roger (Aug 14, 2017)

mattwalt said:


> Actually Aluminium... you always need to be sure surfaces are clean - oil-free and well keyed - even with pins (no matter what material) when gluing.


Are glued together slingshots actually the best way to go. Seems like a slingshot made of one piece of solid and strong material would be better than gluing together several thin not so strong materials.


----------



## mattwalt (Jan 5, 2017)

JR - I'd tend to agree actually - I think if its possible to either cast or laminate up as or work from a solid block is by far the strongest option. But its probably also potentially the more boring.


----------



## chuckduster01 (May 30, 2015)

Jolly Roger said:


> mattwalt said:
> 
> 
> > Actually Aluminium... you always need to be sure surfaces are clean - oil-free and well keyed - even with pins (no matter what material) when gluing.
> ...


I'll exclude aluminum for a minute cause I do not work with it, but when it comes to wood and phenolics, the glued up laminations can be many many times tougher than a monolithic piece of wood. Perhaps I put too much faith in our excellent modern glues, resins, epoxies, etc, but I think we have it made and them adhesives are amazing. I have demolished some old homes and the hardest things to destroy with a trachoe are them laminated carrier beams. Normally have to get off the machine and actually cut them. A machine that can crush your truck/car or swat it around like a toy is simply not enough sometimes with the laminated stuff. I can swat at a house and make it disappear quick, but when that boom stops and grunts, quite often it is a laminated beam that caused that stoppage.


----------



## mattwalt (Jan 5, 2017)

One thing that can happen with aluminium is that it heats up real quick when you're working on it - and if its sandwiched between some nice heat insulation like wood or plastic you can actually burn the glue.


----------



## chuckduster01 (May 30, 2015)

mattwalt said:


> One thing that can happen with aluminium is that it heats up real quick when you're working on it - and if its sandwiched between some nice heat insulation like wood or plastic you can actually burn the glue.


As slow as I work, that might not ever be an issue. :rofl: I get what you are saying though, the way aluminum transfers heat is why a lot of bullet molds, cooling fins, radiators, etc are made out of it.


----------



## Winnie (Nov 10, 2010)

Pins look cool.


----------



## Abenso (Apr 28, 2017)

chuckduster01 said:


> Jolly Roger said:
> 
> 
> > mattwalt said:
> ...


I'm a mechanic and I will concur. Modern adhesives, epoxys, and resins are generally many times stronger than what they are bonding. We use a panel bond adhesive to bond body panels on cars and after an accident most of the time the only part left is the parts that are glued together. When it says permanent it means permanent. There is a product called quick steel. It's a putty like substance but after its been kneaded and mixed you mold it how you like than let it set for 24 hrs. After which you can drill and tap it and it will bond steel parts. It's basically steel putty

Sent from my SM-S920L using Tapatalk


----------



## Ukprelude (Apr 17, 2016)

Abenso said:


> chuckduster01 said:
> 
> 
> > Jolly Roger said:
> ...


We used to use that stuff to fix car exhausts when they broke, great stuff 

Sent from my SM-G935F using Tapatalk


----------



## Abenso (Apr 28, 2017)

@ukprelude I wonder if you could make a catty from it...

Sent from my SM-S920L using Tapatalk


----------



## mostho (Mar 28, 2017)

mattwalt said:


> Same reason people put them in knives...
> 
> There are a few various reasons for this - but ultimately its top keep the scales attached in case anything fails.
> 
> Ambiant moisture / temperature fluctuations etc. and using materials which undergo different changes as a result (different density woods (or grains running in opposing directions even), plastics which are impervious to moisture. But also teh adhesives used. These days they can be fantastically good - but when you're sticking 2 different types of material together its the only bond - and failures can and do happen.


nailed it


----------



## Ukprelude (Apr 17, 2016)

Abenso said:


> @ukprelude I wonder if you could make a catty from it...
> 
> Sent from my SM-S920L using Tapatalk


Hmm not too sure but I imagine it could certainly be incorporated into a frame

Sent from my SM-G935F using Tapatalk


----------



## chuckduster01 (May 30, 2015)

Abenso said:


> @ukprelude I wonder if you could make a catty from it...
> 
> Sent from my SM-S920L using Tapatalk


I had one built out of pigputty (2 part JB weld in a cored stick basically) once, just kneaded the putty together and formed it around a wire core made of coat hanger wire. Used it for quite a few years until I lost it one night frog giggin. Should be entertaining for the next species to inhabit this planet when they find it in the limestone that was only marl when I lost it. :wave:


----------



## Ukprelude (Apr 17, 2016)

chuckduster01 said:


> Abenso said:
> 
> 
> > @ukprelude I wonder if you could make a catty from it...
> ...


That's what I was thinking, this putty used as a sort of overcoat if you like. Would loved to have seen a pic of the one you made  and yeah it's amazing to think that one day you're frame may be found and will the people/species that find it even know what it is!? Haha

Sent from my SM-G935F using Tapatalk


----------



## Abenso (Apr 28, 2017)

I smell a project! An adhesive based catty

Sent from my SM-S920L using Tapatalk


----------



## chuckduster01 (May 30, 2015)

Ukprelude said:


> chuckduster01 said:
> 
> 
> > Abenso said:
> ...


When I first made it, it kinda resembled a grey y shaped turd, with fingerprints and hand wrinkles imbedded in the finish. Over the years it got some sanding and polishing by intention and some nice patina just from use. It was a nice shiny dark charcoal grey at the time I lost it. I miss that shooter, it was pertnear perfect.


----------



## Abenso (Apr 28, 2017)

I was gonna ask about the finish

Sent from my SM-S920L using Tapatalk


----------



## chuckduster01 (May 30, 2015)

Abenso said:


> I was gonna ask about the finish
> 
> Sent from my SM-S920L using Tapatalk


Finish was a ground in and polished by use combination of sweat, dirt, grime, frog slime, muck, fish guts and other what not young country lads get on their hands.


----------



## mattwalt (Jan 5, 2017)

LOL - miss those days.


----------



## chuckduster01 (May 30, 2015)

mattwalt said:


> LOL - miss those days.


I still live it on the occasional weekend. You're only as old as ya act right? :lol:


----------



## Talaman (Sep 13, 2019)

Apologies for being off topic:-

*UKprelude*, would you mind sending me a P.M please I have a question for you?

Many thanks,

Geoff

Thanks,

Geoff


----------

