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[raflaunches]

Hi Everyone,

I am uploading this info and pictures so far for my Dad Steve, who some may know as computer illiterate  .  Whilst I have been building the mighty HMS Gnat in 1/32 scale my Dad has been cutting out the frames and keel of his pet project, a WW2 CMB.

The boat in question is very similar to the WW1 55ft CMBs built by Thornycroft but differed in the bow area.  The engines were side by side instead of being staggered and the bow was closer to a hard chine design instead of the round bilge of the original vessels.
CMB No 216 was ordered by the Royal Navy on 7/6/1940 she was completed on 3/1/1941, small, lightly armed but fast (40knots +) however she was not to survive long.  On 23/5/1941 along with her sisters she was destroyed by German aircraft at Suda Bay, Crete.

My Dad is building the model to 1/12th scale making the hull 55inches long oa and a beam of 11inches.  She will be powered by two 12v Bosch car heater motors.  Using plans from John Lambert, he has built all the frames from hardwood strip and used square ramin for the chines and stringers.
 


















Currently my Dad is building the engine mounts before he starts to skin the hull with a layer of 1/32" marine ply and strips of 1/16" marine ply for the planking.
Does any one have any more information or pictures of the WW2 CMBs as we don't have any pictures of a real one? We visited Duxford where there is a WW1 example and a model similar to what we are building but not the correct type so anything would be appreciated.
On behalf of Steve Brown...

Nick B

[longshanks]

Might be worth trying the Coastal Forces sights

Coastal Forces Heritage Trust    http://www.coastal-forces.org.uk/

British Military Power Boat Trust     www.bmpt.co.uk

Coastal Forces Veterans       http://cfv.org.uk/

Hope this helps

[DickyD]

Get in touch with Christian [cds123] he is our coastal forces expert. Send him a PM.

http://community.webshots.com/user/cdsc123

[Dreadstar]

All that I can find out so far is that she was a Thornycroft type 24 MTB. 74ft 3in x 16ft 7in,(Though 213-217 appear to have been around 60ft oa,which were requisitioned from an order destined for the Phillipines)triple shaft, Packard 3600bhp engines.(42 KTS)
 Armament:- 2 x 21"tt;2 x 0.5"mg;2 x 0.303"mg;4-6 DC's or mines.  I'm having terrible trouble finding any pics of the class.

[mikearace]

Try Chris at HSL

http://www.hslmouldings.co.uk/thornycroft_mtb.htm

He has an immense knowledge of all things coastal forces.

[raflaunches]

Hi everyone,

Thanks for the replies so far, I'm showing my Dad all the responses and your suggestions, one day he might learn how to use this new fangled piece of technology called a computer.

I managed to see a copy of the plans he is using (whilst he wasn't looking), CMB 216 had two Thornycroft R12 engines and had two 18inch torpedoes that were dropped off the back of the boat.  They were almost identical to the WW1 CMBs apart from the engines being side by side and a hard chine style bow area.  The superstructure was changed according to the plan to be more aerodynamically pleasing.  The plan also shows two twin lewis machine guns and two depth charges that could be rolled off the side.
That's the problem with my Dad he likes the completely obscure! .
Thanks so far.

Nick B

(on behalf of Steve Brown)

[raflaunches]

Hello everyone,

Here are some pictures of the build so far...















Steve has decided to use 1/32" marine ply to sheet the hull and plank it because of the superior flexibility of the thinner ply.
He has built the hull step from 1/16" ply and skinned it with 1/32" to strengthen it because this is what it will be sitting on at speed.
The torpedo (x2) was made three years ago by my Grandfather from aluminium tube with solid nose and tails, and will sit in the trough as seen in the pictures.  They were pushed off the stern by a piston that sat beneath the crew cockpit!

Information we have been told so far is that the WW2 CMBs were used in a clandestine role in the Mediterranean and were unlucky enough to be caught in the Suda Bay attacks made by the Germans and Italians in 1941.
On behalf of Steve Brown

Nick B   

[CJ]

Try this book - If you can find a copy in a library, 'Allied Coastal Forces of WW2, vol 1' by John Lambert

Loads and loads of info that has really helped me loads....If you can't find or need anything specific I can copy for you or nearly finished with so will be on e-bay soon !!

CJ

[raflaunches]

Hi CJ

Thanks for the recommendation and offer, but I already have both vol 1 and 2 in my collection.  Whilst there are references to the CMBs of WW1 and a couple of pictures of them, unfortunately they don't show the WW2 versions.  I have spoken to John Lambert on several occasions about these elusive boats and well as many other obscurities but there are few pictures out there, and that comes from the man who drew up the drawings my dad is using.  Once again thanks.

Nick B

[mark w]

Keep it coming  .

Mark

[raflaunches]

Hi everyone

As requested some more pictures of the build so far, my dad has actually learnt how to use a digital camera .






















As the photo sequence shows he glues the 1/32" ply using 'Howdens' superglue to the main chine first and allows to dry, being held in place with clamps.  Once dry he glues to the next chine or stringer and once again holds in position until dry.  He has managed to do the entire rear section of the model like this.  This will be covered with another layer of 1/32" ply cut into planks and laid diagonally as per the original boat.

My dad would like to know if any one knows what colour semtex rubber would be because the plans state that the forward deck and hatches were covered with it?  I would have thought it would be either dark grey or green but I am not sure, does anyone have any ideas?

Finally for the moment,  I would like to thank 'Danny' for supplying pictures of CMB M103, whilst its an earlier vessel the pictures of the bridge area have given my dad an idea to what the cockpit would look like.

Nick B

[deadbeat]

White Ensign Models produce a large range of WW2 colours in tinlets and you will probably find what you want there.

[raflaunches]

Hi Everyone,

First of all thanks to 'deadbeat' for pointing us in the correct direction, the white ensign paint range says that semtex rubber is a medium-dark green which was trowled on as an anti-slip paint.

My Dad has completed the first skin phase and will start shortly on the planking.  This will be 1/32" marine ply which will be 45 degree diagonal on the bow area changing to a horizontal plank on the stern.  He is waiting for his prop shafts to arrive from Prop Shop he has worked out that the prop shaft length will be in excess of 40inches long .
Here are some pics so far...



















Until next time.

On behalf of Steve Brown

Nick B

[Tug-Kenny RIP]

 He is waiting for his prop shafts to arrive from Prop Shop he has worked out that the prop shaft length will be in excess of 40inches long .

Hi RAFLaunches,

This does sound like a lot of metal inside the boat. Are you working to plans ?

regards

Ken

[raflaunches]

Hi Ken

We were quite surprised at the length too, especially that there are two shafts required!

My dad is using the John Lambert plans that we got via Traplet.  Its the only one available of a WW2 CMB without going through the National Maritime Museum plans service which can be quite expensive.

Regards

Nick B

[raflaunches]

Hi everyone,

The prop shafts turned up yesterday after being thrown through the letterbox by the postman!  Obviously he has no respect for the model boater and his prized components but they arrived more or less intact  .

Here are some pictures of the shafts in place and the outer planking.











Looked through the latest issue of Marine Modelling International and spotted a similar boat on the Bury Motor Marine Stand at the Blackpool show, does any one know whose model it is are any way of contacting them, as we are curious about the camo scheme used?

On behalf (once again...) of Steve Brown

Nick B

[expat flyer]

Here's a link to a close up picture of 213 and brief timelines of the rest.
http://lemairesoft.sytes.net:1944/pages/page.aspx?univid=120060

You have an unusual subject and a scale to do it justice. I hope you will find and share all the details necessary.

Jerry

[expat flyer]

A Pathe News clip with some details - a requisitioned Philippine boat.
http://www.youtube.com/watch?v=SIc4wn7K-a8

Jerry

[John W E]

aye aye there

if you do a search on the web for Model Shipwright book - I know they did a plan for a 40 foot coastal motor boat - I know it is shorter than the one you are building but I am sure there is write up that goes with the plan and it may help you.   I am sure someone on this forum will have the magazine and the information.  Tell your dad the build looks really good and is he going to double diagonally plank the hull?

john

[raflaunches]

Hi Everyone

Expat flyer, thank you for the links to the picture and film footage of the CMBs, its the first pictures we have seen of any of the WW2 CMBs, the camouflage scheme seen clearly on the stern area is especially helpful as we had no idea to the original paint scheme would have been.
We aim to due it justice using the picture you have kindly pointed us towards, don't worry we will keep everyone updated of this build.

John (Bluebird), thanks for the advice, I have just found a copy for sale on amazon with the plans you mentioned hopefully it will arrive in the post this week.  Thanks for the comments I'll pass them on to my dad, I'm sure he will appreciate them very much.  He has just started to double diagonal the outer skin on the underside of the bow area and has completed the forward skin on the port side, hopefully pictures to come will show this.

Thank you to you both,

Nick B

[raflaunches]

Hi everyone

My Dad has completed the forward underside and the port side external planking.  He discovered that he could not diagonally plank the rear hull sides and underside due to the curvature of the hull.  It created problems with the planks being laid along side each other bending away from each other and a filler plank being fitted inbetween each plank, something he believes that Thornycroft would have prevented.
So he has resorted to the original 55ft CMB from WW1 idea of horizontal planking the aft hull sections and keeping the diagonal planks on the forward sections and blending them in the middle.

I made a promise to my dad that if he made my 6inch guns for my gunboat, I would make his 1/12th scale 0.303" Lewis machine guns for his CMB.  The pictures show the basic parts for the barrel, main body of the gun and the ammo drum.  I have started to add some detail to the main body with cooling gills made from 90degree angle plastic card, whilst the ammo drum is a section of a solder tube.  I will start to carve the butt of the gun next week...













Until next time...

On behalf of Steve Brown

Nick B

[John W E]

Hi ya Nick

I hope your dad has access to your p.c. so he can have a bit of a read of how to overcome the problems encountered over double diagonally planking of hulls with a radius.  I am posting a link to the trawler build which I did a while ago which is diagonally planked - see below.

Somehow I have the feeling I am 'teaching one's granny how to suck eggs' looking at the skill and craftsmanship that your dad has put into this build.   There is also an alternative way of double diagonally planking - and this is by using a thinner planking which I did in the 63 ft whaleback build.   Inner planks were something like 10mm wide x 1.5mm thick obechi wood - then I planked over the top using 4mm x 5mm mahogany strips which were supplied by Mantura Models and using this method I had no problems with various widths of planking.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=13888.msg133091#msg13309
john

[raflaunches]

Hi John

Thanks for the advice, read it with great interest, its fantastic to see how its done properly.  My Dad was going to do a very similar method to your hull construction but decided not to because the entire hull was filled in so no planks are visible, I thinks he is doing this way because its easier too!  Its an interesting subject making the hull from double diagonally laid planks, we have made about three or four boats in this way and it has made a very strong hull.  Our Walton 65ft ASRL has two layers of 1/16"ply (its built like a tank ), and was relatively easy to build but all of them have been hard chine designed and the CMB is his first round bilge launch so its been a steep learning curve for him.
Cheers for the help, hope its still interesting for everyone...
Regards

Nick B

[raflaunches]

Hi everyone

A quick update so far...

My dad has near enough completed the outer planking of the hull, seems a shame that all of it will be hidden because the planks gaps were filled and sanded/filed smooth to create a 'aerodynamic' hull.  The prop shafts are fully glued in and he has informed me that he will start making the prop support brackets soon (all four of them!).
He intends to paint the hull soon with a primer coat to act as the filler between the plank and sanding smooth between coats, building up the coats and impregnating the wood.
I received the  copy of Model Shipwright last week that Bluebird suggested, the article is very interesting but some thieving g*t has nicked the plans but I got the general idea!
Hopefully more pictures to come next week.

Nick B

[raflaunches]

Hi Everyone,

Apologies for this update being longer than expected, but we spent the last weekend removing about 60-100 tons of mud from our local lake at Wicksteed Park!

My Dad has finished the sides and the underside of the hull, and is now slowly finishing the deck areas with 1/32" ply and a 1/16" piece of ply for the bow area (to make it stronger).









He says that he will start painting the hull will a primer coat next week, but first he will make the strengthening plate and exhaust outlets that run along the hull sides.

More pictures to come next week, hopefully!

Nick B