Hello,

Are there any experts out there that have successfully hooked up a HL Recoil Unit to a Tamiya DMD? Is there a wiring diagram and or photo guide available?

I have had a search in the forum threads but have not found anything on the subject.

I have had a go but cannot get it to stop after one recoil action.

I think it is just a question of setting up the wiring on the switch mechanism the right way.

A picture and a few wise words would be greatly appreciated.

Cheers

Alan

Can you show me what you have done? I tried to have the Heng Long recoil from harvesting power from the upstroke on the cannon elevation in my Sherman. I just ended up loosing upward cannon elevation

I have not done anything much to show at the moment. All I have is a Tamiya Tiger DMD/MFU on my work bench with a HL recoil unit (out of a JP) layed out and I have been trying different wiring combinations hoping that I can get it to recoil.

This risk is of course that if you do it wrong you burn out the resistor in the MFU and then it will simply run constantly for 30secs no matter how it is wired. I do not want to make that mistake so wanted to ask for help first.

There must be someone out there that has done it.

My main aim to use one of those new HL Tiger Tank recoil units in my model that is both a recoil unit and an elevation unit in one housing. The recoil movement is more correct than the Tamiya version (fast back and slow forward) and the whole thing is more efficient in terms of space usage, robustness and not to mention is more reasonably priced than the equivalent tamiya parts.

Cheers

Alan

In the long run, I think it would be best to use the Tamiya recoil.

It's much cheaper than a Tamiya DMD.


- Jeff

I am sure it would be a really straight forward job for anyone with a bit of knowledge and talent in the electrical trade. Any electricians, engineers or gifted model makers out there?

Cheers

Alan

yes am interesed to anyone tryied it out already?

I think F's right. the recoil units are cheap compared to a DMD or MF unit, dont think I would want to take the risk. not for the price of a recoil.

Yes but the idea is if you know what you are doing there is no risk and you end up with a better model at a better price. (not that price is the all important factor, I just think the new HL Tiger recoil looks great)

I bet someone clever has done it already, I have been wanting to make this upgrade for ages (am working on, wait for it, Wittmans Tiger 007, yes another one lol) and am now thinking about the details for the electrical installation and placing my order with Asiatam for various bits and pieces.

I have seen the HL Tiger recoil in action and really want to build it into my model (Tamiya Tiger FO model) it I can.

Cheers

Alan

A clever person wouldn't bother. The Tamiya recoil units are "cheap" which is the tone for this thread.

I'm putting all Tamiya gear in my HL KV-1 which will soon be turned into a KV-122. Which this model will not be cheap at all, but a better model.


- Jeff

My Sherman DMD doesn't have the recoil option, but I would think that that if a plug exist on the TIGER DMD for a recoil, it would be quite simple. In order for the Heng Long recoil to work all it needs is one pulse of a current in the negative direction and you will be in business . Hook up a voltmeter to the plug, and find out which prongs delivers that requirement.

My Tamiya Sherman DMD elevation circuit could not handle the current requirement of the Heng long recoil motor, and It failed in one direction. THe recoil unit must draw more amperage as it is working against a fully extended spring to start the proceess. The Tamiya electronics that hande the gun elevation could not handle the load. In hindsight I should have tried this on an unloaded motor first.

I would think that a DMD with a recoil outlet probably is engineered to handle the load. When experimenting though, that is the risk you take. Just try it with an unloaded motor first, and you should be fine.

Hi Alan the only info I have at the moment is this :-

Tamiya recoil wiring

WHITE WIRE = Start recoil (+) fire
BLUE WIRE = Battery negative (-)
GREEN WIRE = Battery positive (+)

Now for the fun bit. I have seen a HL recoil rewired to work the " right " way which is fast recoil and slow return. I'm sure YHR made the same mod to a HL unit here a while back. The only issue here is the mod I saw was wired to work with an RX18 and you have to use a microswitch on the recoil unit to control the firing cycle just like a Tamiya unit ( pm me if you want the name of the other site where I read about this mod ). So the thing is you need to see how Tamiya wire up there recoil copy it and in theory it should work fine. It's a bit of work I know but if it works yon can then use Tamiya DMD's and MFU's between your tanks. Pictures show how I have modified my Tamiya recoil wiring to be plug and play by cutting and splicing the origional wiring with a Futaba servo extension lead so I can plug any recoil unit ( provided I wire it up right ) into my Tamiya electronics. I have done this with a HL Stug and it's a bit of a tight fit but it all works bar the recoil which I have to modify to work the "right " way and wire up the same as my Tamiya Tiger 1. I have pluged the Tiger 1 turret into the Stug's electronics and ripped off a few shots and everything worked OK.

Great feedback Tankman and YHR. Thanks a million.

I also found this info which is useful:



Would love to see a photo example of a working setup to avoid any possibility of mistake. Looks like you are just about there with yours.

Were are making progress in the right direction that is for sure.

Cheers

Alan.

This is very useful info. Without a doubt this will work Using the above you would wire the green wire through a contact swtich to one motor pole. The Blue wire to the other motor pole. The white wire would go to the normally closed or middle junction on your contact switch.

The way this works is that the blue and green wire supply current to the recoil motor. SO the motor is happily running along until the bbl reaches it's full extended postion and the contact switch is open. This cuts of the positive supply from the green wire and the motor stops. All the white wire does is supply a momentary pulse of positive power to start the motor. This action of starting the motor moves the gear inside the recoil mechanism and the spring pulls the bbl back. As soon as this happens the contact switch is closed again and the green wire is again allowed to feed power to the motor, and away it goes again unitl the contact swtich is opened again.

They only thing that can cause you grief is how much load the motor will draw from the Tamiya system. Working agaist the spring may cause it to almost stall, and if that happens it my draw more amps then the Tamiya circuit can handle, and poof. From what I learned with my Sherman I would do this without the spring on the recoil mechanism first. This will minimize the load, and you can test to make sure the motor is turning in the right direction. If it isn't you just have to reverse the motor poles. Try using the weakest spring posible to get the bbl to retract, this will minimize the load on the Tamiya electronics.

Thanks for posting those pictures and observations Alan and YHR very usefull indeed. As soon as I get a few days off work I'm off down to the local electrical shop for a few microswitches. I will keep you all informed of progress. I,m also going to try and rig an Asiatam unit to run off Tamiya electronics by direct wiring the elevation motor via a JST connector then wiring the recoil unit using your diagram and a new reliable microswitch ( the origional was knackered from new ) and in theory it should work fine. I must also look round for some weaker springs for the return on the recoil ( might use small elastic bands for testing ) All the best for now guys
Alan

Hello,

The current from the Tamiya DMD is more than enough to run the HL recoil. I hooked up the + and - negative poles direct and it ran fine. The tricky part is wiring the switch right so that it cuts out at the right time. A weaker spring would not hurt though, that is for sure. Safety first.

Hooked up directly, and with no micro switch cut out, (that is the hard part that needs to be solved) the motor runs for about 30secs and then stops on its own accord when the DMD shuts the pre timed power supply down.

Another option I thought of was to wire a series of resistors into the circuit so that the power supply lasted just long enough to give you one recoil. This works on the old Elmod setups and works really well too.

The old Elmod version 1 recoil instructions look like this:



I did try this on a Tamiya DMD some time ago however could not get the right balance of resistors etc to achieve just one recoil, it was either too many or not enough. But the potential was there. I expect someone with the right know how could work out exactly what resistance was required and get it to work ok. (this way you could get a DMD with a damaged recoil circuit to work again).

I look forward to seeing how you get on with your experiments.

Cheers

Alan.

If you get 30 seconds of power, that should be more then enough to get the Heng Long recoil to cycle. Just let the micro switch do its job, and it will stop the bbl in the extended postion. You need less then 5 seconds of power once activated.

YHR, you have hit the nail right on the head. The million dollar question is how one wires the switch up so that it stops at the right time.

Can the HL switch be used and if so how does one wire it up. This would be the best option as it would be practically a simple plug and play solution.

Must another switch be used in its place if the HL switch cannot be used and if so how will this be located and wired.

I feel a breakthrough in recoil technology it not far away.

Cheers

AL

Hi Guys,
FYI, there are two different sizes of Tamiya recoil units. One large for the KT and larger turrets and one small for the Pershing and the smaller turrets. I would recomend the smaller as it may ease instalation. You will also need the metal bracket the bolt to the rear of the mantlet and screws into the bottom of the recoil unit.

You have to place the micro switch on the heng long recoil. Position it so that when the barrel returns to fully extended it shuts off the power.

Did anyone get this to work I have a Stug III that Id ike to convert to Tamiya DMD and MF units but would like to keep the HL recoil mech .

Jimmy