FV107 - CVR(T) - WIP

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Fabrice

Re: FV107 - CVR(T) - WIP

Post by Fabrice » Sun Aug 13, 2006 2:57 pm

Hi Andy,
Back from Dorset. Bov had a Scorp blasting round the arena last Wed. Do you think you will achieve scale speed?
I'll look out what CAD files I have for the turret.
Looking good!
Cheers
Fabrice

Andy T

Re: FV107 - CVR(T) - WIP

Post by Andy T » Mon Aug 14, 2006 9:05 pm

Things have been coming along nicely whilst I was away. I've been down to Bude in Cornwall and just outside is a small military vehical collection (Dinscott Tank and Military Collection) and tucked in a shed is a Sabre. Took some photos of the track and drive sprockets (to see what I've let myself into) not briliant due to poor lighting condition and no tape measure but anyones welcome to have a copy. Tried to buy a spare link for modeling purposes but none spare.

Now it's time to get on with this casting setup!

cheers Andy T

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Mon Aug 14, 2006 9:26 pm

Fabrice,

Thanks got your email matey, IV is busy churning away on it now, will see if it's going to be of any use, fingers crossed!!!

Stop press: apparently IV has accepted it, after thinking about it for the last 2 hrs. Will let you know how I get on.....

Andy,

Don't worry about the track link, as Bob G has offered me a borrow of one of his 1/8th scale ones to copy. So it should be under control, no sense in spedning cas if you don't need to! Can you email me a copy of these pictures I would be very grateful.

Also just heard today that I'm moving projects within my company, and will be very busy with work work, for the next couple of weeks / month so progress might slow right down for a while. However I'm hoping to get the track link, the road wheels, suspension points and the hubs sorted out soon. once confirmed I can then create the 2d dwgs and have the first batch of dwgs available to give out to all who want a copy.

Fingers crossed I can maybe yet get the chassis built by crimbo.......

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

Andy T

Re: FV107 - CVR(T) - WIP

Post by Andy T » Mon Aug 14, 2006 9:31 pm

Andy

send your email address to andrew_thurlby@hotmail.com and I'll send them direct.

Andy

raimian
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Re: FV107 - CVR(T) - WIP

Post by raimian » Tue Aug 15, 2006 11:35 am

to make a working crane for your warrior, i would suggest using some hydraulic/pneumatic systems designed for ant-weight battle bots.

the robot market place as a notbad range of pneumatic stuff designed for ant weight battle bots.
http://www.robotmarketplace.com/marketp ... _pneu.html

or you could use the lego tchnics ones from here;
http://www.active-robots.com/products/l ... ares.shtml

i hope this helps.

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Tue Aug 15, 2006 12:36 pm

Ramian,

Thanks for the links, but "been there, done that and bought the T-shirt". have looked at all these options plus some more main reason is due to the actual physical size of the rams needed and due to the way a ram is manufactured.

For a free stroke length of say 100mm, you need to have a cylinder which is at least 100mm long to house the piston. Then on top of that there must be some space designed into the housing to incorporate the seals. So in effect the actual ram size needs to be around 150mm but still on gives you a 100mm stroke.......... essentially its this ratio I'm struggling with......

Anyway thanks for the links anyway.

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

missyd
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Re: FV107 - CVR(T) - WIP

Post by missyd » Tue Aug 15, 2006 5:45 pm

Maybe you can try one of these suppliers .... or use some sort of double cylinder (2x50mm). And I suggest to use a hydraulic system instaed of a pneumatic one. Lot of parts are for sale for scale excavators ....
Did you look at the hydraulics used for roboters (not toy roboters) etc.

http://www.modellhydraulik.net/html/zylinder.html
Danielle

Make Love not War ....

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Tue Aug 15, 2006 7:16 pm

MissyD,

yep, been there tried them...... incedently they will make a custom cylinder for you if you give them the dimensions you need..

Irrespective of which cylinder design you go for, hydraulic or pneumatic you still have this ratio i was talking about earlier. it's fine on large cylinders because the corresponding value for the seal size is a small percentage of the overall size. However once your into the small stuff it becomes more of an issue.......

I think the answer is a motor and lead screw type system with a alloy cylinder to hide it all.

Anyway, speak to you laetr

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

Fabrice

Re: FV107 - CVR(T) - WIP

Post by Fabrice » Tue Aug 15, 2006 11:31 pm

Andy,
Peter Mueller has gone the leadscrew route on his models for working lift capacities. But for the first stage ram it might be worth looking at the flexible sheathed rods (oh er missus!) available for model aircraft. I am toying with the idea of incorporating them into the lifting rams for a 1/16th M74 A-frame jib. The rod and sheath gets fed into the bottom of the cylinder and is driven by a hi-torque servo mounted elsewhere. The limitation is the smallest radius the sheath can be operate in without binding.
These actuating rods can be got in most R/C aircraft shops and are comparatively inexpensive.
cheers, Fabrice

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Wed Oct 25, 2006 1:57 pm

Fabrice,

Thanks for your msg. I've dropped the warrior for the time being, certainly until I get my new house (tank workshop / Garage). The Scimitar however is still moving forward albeit very very slowly - design only.

Bob has kindly siad he's going to lend me his master link of the sultan and possibly (hopefully) an actual cast alloy link (1/8) for me to scale and draw up.

I need to evaluate the roadwheel a little more, to see if they would be best to be cast or machinied. I can machine them for around £300 for the 24 I would need (20, req, + 4 spares) or I can get a master made for nothing in wax, and then I'm charged mould and casting costs. I suspect this would be the better way for a club / open project.

Thoughts on this is appreciated.

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Sun Nov 12, 2006 11:06 pm

Hi all,

Managed to get some time this afternoon to get some more of the Scimitar completed.

Have now started to finalise some of the stowage boxes. i have also found an excellent reference for the model. I am modeling a late 2006 version (engine cowling mod, and air inlet mod as far as I can tell anyway!).

The stowage will be made from styrene, mostly 1 - 2mm thk, will beef up the internals with use of a glue gun me thinks.

Bobs sending a me a track link or three to CAD up and use so once these are in place i can properly finalise the running gear.

With the running gear finalised and the top hull finalised, i should by then have my new house and hopefully a tank workshop (garage) fingers crossed by teh summer I can maybe get some of the bits made.

The hull is 2mm sheet steel, and will be welded together.

BTW, I know the current engine cowling is not correct, but fingers crossed it will be by crimbo. Along with the math which supports my motor / battery design.

Constructive comments greatly received..................

Cheers
AndyR

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THE BATTERY SPACE / PROBLEM
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Last edited by AndyR on Mon Jul 11, 2011 12:04 am, edited 1 time in total.
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

Fabrice

Re: FV107 - CVR(T) - WIP

Post by Fabrice » Wed Nov 15, 2006 1:05 am

Hi Andy,
Looking good. Are you going for the Sabre turret? And do you anticipate heat build up with the closely packed motors and batteries?
cheers, Fabrice

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Wed Nov 15, 2006 11:07 pm

Fabrice,

No the heart is set on the Scimitar / Scorpion turret I'm afraid.........

With regards to heat build up, I would say that yes this is likely to be a problem, although I have not run the calcs yet.

I'm actually building an excel spreadsheet, which i'll make available to members of the club so they can work out what size of motor is required.

Ie you know the weight, scale speed but uncertain as to the power or torque required. Once my spreadsheet is finished you should just be able to enter the variables and it'll spit you out the Max Motor Power required. Its shaping up nicely, i'm just brushing up on my Kinetic, potential energy calcs...........Can't belive I've fogotten so much in such a short period of time!!!!

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

Andy T

Re: FV107 - CVR(T) - WIP

Post by Andy T » Tue Apr 03, 2007 12:01 am

Hello Andy

Hope everthing is OK.
We're waiting eagerly for an update on this project.
My two boys have written early to Santa for one of these each! What are the chances

regards Andy

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AndyR
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Re: FV107 - CVR(T) - WIP

Post by AndyR » Wed Apr 04, 2007 8:27 am

Andy,

Hi, its currently the subject of a Thesis report for my Mechanical Engineering degree.

It is almost finished, the turret design is complete, i haven't finished the turret slew motor design but i guess that can be done by however. Pictures will be posted later on this month - honest.......

Cheers
AndyR
Happy, Happy, Joy, Joy, Happy, Happy, Joy, Joy...........

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