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» Forum Category: PT Boats of WWII
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» Forum Name: PT Boats - General
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» Topic: 37mm Mk4
http://www.ptboatforum.com/cgi-bin/MB2/netboardr.cgi?cid=101&fid=102&tid=3705



So I'm looking to make the 37mm, even though it's not needed for my current build. I've gathered up Al's drawings and all the photos I could scrounge on the web... but the available web shots are just not showing all the details I want. So, I stopped by the USAF museum at Wright-Patterson to get some close-ups of their example, which is set up as the entire P-39 power plant and gun installation in a separate exhibit.A few snapshots below (I have more!).

Questions:
Anyone else have a photo album, perhaps from PT-658, showing details of the handle/trigger and jury-rigged pedestal?
Did these installations use borrowed pedestal yokes from 20mm's?
Any stories about how the adaptation was developed? Was it up to each crew, or did the tenders' shops develop the hardware?
Thks!

[image]https://matthewsmodelmarine.files.wordpress.com/2014/10/img_8541a.jpg?w=621 [/image]

[image]https://matthewsmodelmarine.files.wordpress.com/2014/10/img_8553a.jpg?w=674 [/image]

[image]https://matthewsmodelmarine.files.wordpress.com/2014/10/img_8556a.jpg?w=300 [/image]

[image]https://matthewsmodelmarine.files.wordpress.com/2014/10/img_8565a.jpg?w=674 [/image]

Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Oct 18, 2014 - 5:42am
Total Posts: | Joined: Unregistered



Patrick,
Al Ross gave me some excellent advice recently on this subject. Go to the aviation side. I found a place selling the Oldsmobile cannon operating manual for $15.

http://www.ioffer.com/i/us-37mm-m4-aircraft-auto-cannon-p39-pt-boat-manual-153311634

Other than that if you search P-39's and M-4 37mm cannon you'll find information. There's a real good site that I can't put my finger on that really breaks down this weapon. I'm sure somebody will be able to find it.

Dave

David Waples

Posted By: David Waples | Posted on: Oct 18, 2014 - 6:02am
Total Posts: 1679 | Joined: Jan 2, 2007 - 9:55pm



That is a neat display, thanks for sharing Pat.




Posted By: Jeff D | Posted on: Oct 18, 2014 - 7:48am
Total Posts: 2200 | Joined: Dec 21, 2006 - 1:30am



No wonder the Russkies loved those P-39s we gave them...the 37 mm cannons in those rear-engine car-door planes chewed up a lot of Krautheads!



Posted By: Drew Cook | Posted on: Oct 18, 2014 - 2:21pm
Total Posts: 1306 | Joined: Oct 19, 2006 - 10:44am



Forgive me, for I have not read all the materials...

...but speaking of 37mm cannons, a question on the anti-tank gun so famously used on PT-109: Was this a one-off usage, or did other boats mount the same weapon?

Thx, Pat




Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Oct 22, 2014 - 9:32am
Total Posts: | Joined: Unregistered



Pat;
I will sneak in here and answer this quick, before anyone really notices, a few boats had them, during the same time period, I have seen one or two photos.
Take care,
TED



Posted By: TED WALTHER | Posted on: Oct 22, 2014 - 1:39pm
Total Posts: 3058 | Joined: Oct 16, 2006 - 7:42am



I noticed Ted! Surprise! Just a comment and I don't know how true it is. These guns seemed to appear about the same time. I was pretty sure somebody had identified at least 3 boats that had the anti-tank gun permanently mounted. I did read that the down side of this gun was that it took several people to operate it. The auto cannon could be operated by one person and could fire automatically. I don't know for sure but I suspect that these guns were replaced by the auto cannons. Maybe somebody knows? Tracy posted a nice photo of a permanent mount for the 37mm anti tank.

 photo nIeyh4z_zps12b17435.jpg

Dave

David Waples

Posted By: David Waples | Posted on: Oct 22, 2014 - 7:34pm
Total Posts: 1679 | Joined: Jan 2, 2007 - 9:55pm



OK, have a reasonable model of the early Mk4 37mm, printable in the usual sizes.
But what mount to use?? Every one from this period looks unique! Anyone have a favorite? Or do I just leave that to the modeler...

Ditto for the "handlebars"...


[image]https://matthewsmodelmarine.files.wordpress.com/2014/11/37m4.jpg?w=800[/image]

Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Nov 1, 2014 - 11:47am
Total Posts: | Joined: Unregistered



I would certainly be interested in one of these in 1/35 scale. Maybe two.

As for the mounts there are many. The most common mounts I see that would lend themselves to 3D printing would be the short tripod mounts. I think they are Mk. XIV but not positive about that. Basically the short tripod light naval mount.

The handle that I see most often is an oval handle or more of a race track shape.

 photo 37mmPT-331_zps04dfb265.jpg

Here's a photo of a boat with 37mm on the this mount.

 photo PT122BillSkadeRON8underwayatspeed1_zps5aaa9eb2.jpg

David Waples

Posted By: David Waples | Posted on: Nov 1, 2014 - 12:50pm
Total Posts: 1679 | Joined: Jan 2, 2007 - 9:55pm



I know the 108 boat had one of the early 37mm's at one time.


Will

Posted By: Will Day | Posted on: Nov 1, 2014 - 6:09pm
Total Posts: 1955 | Joined: Oct 8, 2006 - 4:19pm



OK, I put the 37mm Mark4 cannon up on Shapeways:
[url]https://www.shapeways.com/shops/patmat?section=PT+Boat+Parts&s=12#more-products[/url]

> Cannon only at this time, too many home made pedestals for me to pick one.
> 1:16, 1:20, & 1:24 scales
> Full set of HE shells
> Barrel is printed, but could be replaced with brass tube- it's straight in this version of the cannon.

I also put up a shell set in investment cast bra$s... the as-cast finish requires polishing. But the cannon set comes with a set of plastic shells.

I haven't made one for myself yet, will post pics once I do.

[image]https://matthewsmodelmarine.files.wordpress.com/2014/11/37b.jpg?w=727[/image]

[image]https://matthewsmodelmarine.files.wordpress.com/2014/11/625x465_2858534_7448820_1415977646.jpg?w=604[/image]

Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Nov 15, 2014 - 12:45pm
Total Posts: | Joined: Unregistered



I finally got around to assembling my 1:24 sample of the early 37mm.

- No pedestal
- No attempt to smooth out 3D print lines here... can be done, but this shows the as-received condition.

Plastic barrels tend to warp, but can be replaced with brass tube (1/8 for 1:24, 5/32 for 1:20).

At my Shapeways shop in 1:24, 1:20, & 1:16 scales.
[url]https://www.shapeways.com/shops/patmat[/url]

[image]http://www.matthewsmodelmarine.files.wordpress.com/2015/06/a20150612_194050.jpg[/image]

[image]http://www.matthewsmodelmarine.files.wordpress.com/2015/06/a20150612_194023.jpg[/image]

[image]http://www.matthewsmodelmarine.files.wordpress.com/2015/06/adsc_0005.jpg[/image]





Patrick Matthews
Matthews Model Marine
http://matthewsmodelmarine.wordpress.com/

Posted By: Patrick Matthews | Posted on: Jun 12, 2015 - 5:33pm
Total Posts: | Joined: Unregistered



Pat;
That looks awesome!!!!!
TED



Posted By: TED WALTHER | Posted on: Jun 12, 2015 - 6:22pm
Total Posts: 3058 | Joined: Oct 16, 2006 - 7:42am



Sweet!

Will

Posted By: Will Day | Posted on: Jun 12, 2015 - 9:57pm
Total Posts: 1955 | Joined: Oct 8, 2006 - 4:19pm



Pat,
There are a lot of us out here that are very interested in multiple copies of the gun in 1/35. Please consider doing some things for the rest of us that aren't building in the larger scales.


Jerry Beasley

Posted By: Jerry Beasley | Posted on: Jun 13, 2015 - 4:06pm
Total Posts: 89 | Joined: Jan 9, 2008 - 4:27pm