Main barrel recoil - anyone successfully done this?

Alan Hamby · Post by **Alan Hamby** » Fri Aug 14, 2009 11:53 am

I know this has been discussed on the forum before but has anyone successfully created a recoil system for the main barrel? I'd like to use a recoil system on the barrel without the blank firer being installed. I just want the barrel to recoil realistically. I'm not using the Armortek blank firing system.

I believe the length of the stroke has previously been determined to be about 96mm. And the inward movement of the barrel needs to be quick while the outward recoil motion needs to be slower. I've read the discussions on programming servos to accomplish this.

What I'm wondering is has anyone successfully accomplished this?

- Alan

Paul Morris · Post by **Paul Morris** » Fri Aug 14, 2009 7:27 pm

Hello Alan.
Yes is the answer to your question, Clive Lockwood has made a very god recoil on his Tiger 1, it uses a large scale servo of the sail winch type with a long arm and a linear bearing fitted into the mantlet, it works very well in my opinion and Clive has also fitted the system into his very good scratchbuilt T.34 .
I think he may be on holiday at the moment {could be wrong} but drop him a P.M. he is a very helpfull fiendly fella and i am sure he will have a chat with you.
Hope this helps Paul

Allan Richards · Post by **Allan Richards** » Sat Aug 15, 2009 7:21 pm

Al, I know the photo is rubbish but I made a recoil system based on a sail winch servo, a crank and a crosshead assembly. Although it doesn't give the differential speed of recoil and recovery but it doesn't look bad either when on the tank.

Alan Hamby · Post by **Alan Hamby** » Fri Aug 21, 2009 1:28 am

Thanks for the info Paul. I've sent Clive a message.

Allan, that is a very interesting picture. How is it attached to the barrel?

- Alan

Martin Cohen · Post by **Martin Cohen** » Fri Aug 21, 2009 12:01 pm

With the system as described, I wonder if it would be practical to somehow spring load the barrel in a way that it works against the servo causing the barrel to extend more slowly after firing than during recoil?

We might do well to follow-up with others who mentioned they were working on this:

Also note the posting by Roland Mann of Sep 05, 2008: "..Tiger I the information for the recoil I used to build my gun came from the "Prelaminary report No. 19" of the Military college of sience in November 1943. On page 4 the "maximum normal working recoil of 580 mm" is mentioned. This works out to 96,7 mm"

And around Nov. 2007 Robin Ellis posted some images of his Futaba servo, providing 3 to 4" recoil.

And going back to Oct. 2005, Matthijs Dijkstra had mentioned something about this "My machinist and I are developing a gas operated recoil recoil system!"

Just trying to help resurrect the idea,

Martin

Lionel Champ · Post by **Lionel Champ** » Fri Aug 21, 2009 8:53 pm

Has anyone looked into how Tamiya achieved this on their 1/16th tiger? It looks fairly authentic to the untrained eye (eg mine). They even have a nine second pause between shots to replicate loading.
Lionel

Paul Morris · Post by **Paul Morris** » Fri Aug 21, 2009 9:03 pm

Hello Lionel.
I have wondered about this before and agree with you the Tamiya representation looks very very good,surely someone with the skill and machinery {like Mark

} could perhaps make an enlarged version of the 1/16 recoil unit hint hint.
Cheers Paul.
P.S. Clives is very good, but as Alan has pointed out with his similar set up it does not have the slowed down return....still good though

Roland Mann · Post by **Roland Mann** » Fri Aug 21, 2009 10:02 pm

Hi Alan, I remember the discussions very well in this forum regarding a recoil system. The reason I'm late here are my hesitations and respect of the strict policy of Armortek regarding blank firing the gun. I respect this very much and send you a PM with an intersting solution - promised.

Best regards Roland

Allan Richards · Post by **Allan Richards** » Sat Aug 22, 2009 11:36 pm

Alan,

Sorry for the late reply but I've been away on business. The end of the barrel was drilled and tapped 3mm through its wall and a length of studding used to come back to the recoil system. Someone has suggested using a spring to give the differential velocity for recoil and recuperation but I fear that the servo I have used would not be strong enough to pull against a spring. It would be possible to make something along the lines of the Tamiya system but it would have to be much more robust to work with the much heavier barrel.

Alan Hamby · Post by **Alan Hamby** » Sun Aug 23, 2009 4:01 am

I've been thinking about the fast rearward/slow forward movement problem, trying to relate it to anything I've seen in the real world. It may sound strange but what comes to mind is my kitchen drawers. I don't know what it's called but they have an "anti-slamming" or "soft close" feature. You can pull the drawer out normally as fast as you want, but when you slide it back inwards they reach a point and then slow down and automatically close slowly. It's just the same motion you'd want from the barrel. I know thats not much of a description but if you've ever seen this kind of drawer you'll know what I'm talking about. Here is an example of the pistons this mechanism uses:

http://www.toolstation.com/shop/Hardwar ... 674/p32435

I wonder if these could somehow be used to accomplish a realistic recoil?

- Alan

Alan Hamby · Post by **Alan Hamby** » Sun Aug 23, 2009 4:10 am

Here's an example of how a soft close piston works:
http://www.youtube.com/watch?v=2C6Brg8yfOo

- Alan

Paul Morris · Post by **Paul Morris** » Sun Aug 23, 2009 8:32 am

Hello Alan.
I know exactly what you mean and i had similar thoughts myself in fact i actually got hold of a set of the drwer closers from work they are built on a quite substantial metal rail which i thought would support the weight of the barrel, i never got as far as trying it because i suggested it to someone and they just dismissed it as a none starter....but i may have a go now i know i am not alone.
Lets see what we can come up with between us.
Cheers Paul

Roland Mann · Post by **Roland Mann** » Sun Aug 23, 2009 8:53 am

Hi Alan, some time ago a TIGER I modeller ask me if I could do a recoil system with the desired speed of movement. We discussed several methodes and I remeber the disadvantages of a servo for the reson of a fast recoil. The weight of the whole assembly to move backward ( when the gun is fired ) is no less than 5 kg. This has to be moved in less than 0.5 sec for the 80 or 90 mm. A small calculation equals to an enormes force, nothing for a set up like the Tamiya one. So next was an cylinder parallel to the gun to shift the whole thing back in 0.5 sec. The gas pressure was intended to come from a COÂ² cartridge. An old COÂ² pistol with trigger and valve was aquired. This solution came never to an end by problems to control the trigger. Too comlicated set up all in all with unsure processing details.

Last the idea of the gas cylinder suvived. The gun moves back in idle by a spring in the cylinder. Speed back is controlled by a small adjustable bleeding valve.

However, still the question how to provide the gas pressure for the cylinder. Probably some of you have the answer.

Roland

Alan Hamby · Post by **Alan Hamby** » Sun Aug 23, 2009 10:58 am

Allan, do you have any video of your system in action? I'd love to see it working.

- Alan

Alan Hamby · Post by **Alan Hamby** » Sun Aug 23, 2009 4:52 pm

I've looked more at the Tamiya system. It seems like there should be a motor strong enough to duplicate this in 1/6th scale although it sounds like Roland may have tried it already.

Here is what the Tamiya recoil looks like in action:
http://www.youtube.com/watch?v=okpvV-hheNE
and
http://www.youtube.com/watch?v=Ix6RmdT76tQ

Here are drawings that allow you to see how the Tamiya recoil works. There is a cam on the big gear that attaches to the barrel and the big gear is turned by a worm gear arrangement:

It just seems that we should be able to duplicate this.

- Alan

Main barrel recoil - anyone successfully done this?

Main barrel recoil - anyone successfully done this?

Main gun recoil.