_GOTOBOTTOM
Modeling in General
General discussions about modeling topics.
How do you remove the flash seam on springs
nheather
Visit this Community
United Kingdom
Member Since: November 12, 2007
entire network: 295 Posts
KitMaker Network: 90 Posts
Posted: Friday, August 11, 2017 - 01:23 AM UTC
Building a Tamiya Churchill kit. The suspension is one big single piece for each side, complete with the 11 wheel arms and suspension springs.

There is a seam run around the complete part including all the springs - so each spring has a seam and on each side with a web of flash between the spring coils.

As the srings are all moulded in place access to them is quite tricky.

Anyone know of any clever methods to remove the flash between the spring coils - a knife blade is too thin but a needle file is too wide.

Cheers,

Nigel
retiredyank
Visit this Community
Arkansas, United States
Member Since: June 29, 2009
entire network: 11,610 Posts
KitMaker Network: 3,657 Posts
Posted: Friday, August 11, 2017 - 03:39 AM UTC
Diligence and a sharp knife is how I would tackle it.
nheather
Visit this Community
United Kingdom
Member Since: November 12, 2007
entire network: 295 Posts
KitMaker Network: 90 Posts
Posted: Friday, August 11, 2017 - 10:10 PM UTC
Tried that - not that successful though.

Combination of access to the springs being a little awkward and my eyesight not being that good - have to use an optivisor.

Cheers,

Nigel
Kevlar06
Visit this Community
Washington, United States
Member Since: March 15, 2009
entire network: 3,670 Posts
KitMaker Network: 527 Posts
Posted: Saturday, August 12, 2017 - 12:29 AM UTC
I use a strip of sandpaper cyanoacrylated (super glued) to a corresponding thin strip of styrene on one side-- this allows me to get between the coils. Also, for really tight places, you can spread a little CA directly on the back of the sandpaper to stiffen it. But, if I'm not mistaken, the suspension on the Tamiya Churchill is mostly hidden-- can you get by with heavy weathering?
VR, Russ
russamotto
Visit this Community
Utah, United States
Member Since: December 14, 2007
entire network: 3,389 Posts
KitMaker Network: 625 Posts
Posted: Saturday, August 12, 2017 - 01:09 AM UTC
I have a set of very small jewler's files, square, round, oval, triangle shapes, that I use to get in the spring detail.
Scarred
Visit this Community
Washington, United States
Member Since: March 11, 2016
entire network: 1,792 Posts
KitMaker Network: 482 Posts
Posted: Saturday, August 12, 2017 - 02:49 AM UTC
I have jewelers files too, they work great but I'll also us a very new, small sharp blade and carefully scrape the seam down.
Kevlar06
Visit this Community
Washington, United States
Member Since: March 15, 2009
entire network: 3,670 Posts
KitMaker Network: 527 Posts
Posted: Saturday, August 12, 2017 - 02:56 AM UTC
I use Jewelers files too, but the springs he's talking about are too tight to get them into without doing damage-- the Churchill has a set of springs on the inside of each bogie set, which are a really tight pattern. I think they are separately molded in the AFV club MkI-V Churchill kits, but the Tamiya Churchill Mk VII kit has them molded along with the bogie housing.
VR, Russ
nheather
Visit this Community
United Kingdom
Member Since: November 12, 2007
entire network: 295 Posts
KitMaker Network: 90 Posts
Posted: Saturday, August 12, 2017 - 03:31 AM UTC
Many thanks for the suggestions. I have plenty of jewellers files (unless you are talking about something much smaller that I'm not aware of) but these are too wide for between the coils of the springs.

As Russ says on this old Tamiya kit all the bogies, suspension arms, springs are moulded into a single large plastic part so access to some of them is quite restricted.

Picture of them in this auction listing

http://www.ebay.co.uk/itm/Tamiya-35210-British-Infantry-Churchill-Mk-VII-Suspension-Assembly-/172373348484

And also, as Russ says, I do wonder how much will actually be visible when the assembly is complete - perhaps I am wasting my time.

Cheers,

Nigel
Scarred
Visit this Community
Washington, United States
Member Since: March 11, 2016
entire network: 1,792 Posts
KitMaker Network: 482 Posts
Posted: Saturday, August 12, 2017 - 07:57 AM UTC
I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.
Kevlar06
Visit this Community
Washington, United States
Member Since: March 15, 2009
entire network: 3,670 Posts
KitMaker Network: 527 Posts
Posted: Saturday, August 12, 2017 - 08:08 AM UTC

Quoted Text

I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.



Patrick, I have a watchmakers set that I inherited as well-- it's well over 60 years old now-- but still not fine enough for those Tamiya springs between the coils. But not much is visible either once the sides go on.
VR, Russ
Scarred
Visit this Community
Washington, United States
Member Since: March 11, 2016
entire network: 1,792 Posts
KitMaker Network: 482 Posts
Posted: Saturday, August 12, 2017 - 10:22 AM UTC

Quoted Text


Quoted Text

I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.



Patrick, I have a watchmakers set that I inherited as well-- it's well over 60 years old now-- but still not fine enough for those Tamiya springs between the coils. But not much is visible either once the sides go on.
VR, Russ



Huh, I've never built a Churchill but now I'm intrigued just to see that suspension up close and give it go. Is Tamiya the only ones who do the suspension like this, as one piece?
nheather
Visit this Community
United Kingdom
Member Since: November 12, 2007
entire network: 295 Posts
KitMaker Network: 90 Posts
Posted: Saturday, August 12, 2017 - 12:16 PM UTC

Quoted Text


Quoted Text


Quoted Text

I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.



Patrick, I have a watchmakers set that I inherited as well-- it's well over 60 years old now-- but still not fine enough for those Tamiya springs between the coils. But not much is visible either once the sides go on.
VR, Russ



Huh, I've never built a Churchill but now I'm intrigued just to see that suspension up close and give it go. Is Tamiya the only ones who do the suspension like this, as one piece?



I imagine it is unique to Tamiya - I have a AFV-Club Churchill too and that is all seperate components.

Remember that the Tamiya kit dates back to the 1970s when Tamiya were producing motorised models - and they were a lot simpler back then.

Cheers,

Nigel
nheather
Visit this Community
United Kingdom
Member Since: November 12, 2007
entire network: 295 Posts
KitMaker Network: 90 Posts
Posted: Saturday, August 12, 2017 - 12:22 PM UTC

Quoted Text

I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.



I'm intrigued now. So you are not talking about the sets of needle files about 140mm (5.5") long. Those range from dirt cheap chinese stuff to decent stuff but the sizes are consistent and too big for what I need here.

I imagine that you are talking about something smaller but when I try googling I just get hits for the 140mm needle file sets.

Cheers,

Nigel
Scarred
Visit this Community
Washington, United States
Member Since: March 11, 2016
entire network: 1,792 Posts
KitMaker Network: 482 Posts
Posted: Saturday, August 12, 2017 - 02:10 PM UTC

Quoted Text


Quoted Text

I'm talking watch maker quality files. I have a set I inherited from my dad that are probably 60+ years old and still work like they are brand new. Smaller profiles and finer patterns, they cut brass and aluminum. I only use them on really small things otherwise I use the chinese made stuff you get from hobbyshops for under 10 bucks a set.



I'm intrigued now. So you are not talking about the sets of needle files about 140mm (5.5") long. Those range from dirt cheap chinese stuff to decent stuff but the sizes are consistent and too big for what I need here.

I imagine that you are talking about something smaller but when I try googling I just get hits for the 140mm needle file sets.

Cheers,

Nigel



I have the cheap chinese but I have needle file set that has finer patterns, sharper edges, multiple shapes like the chinese ones but much higher quality and a bit smaller. Dad used them when working on firearms, and when he was working as a machinist. I know they are expensive and I don't know if you could even buy them now. They came in their own case with I think is bakelite. I've used them to clean up everything. They can get in tight places and I've used them on resin, white metal, brass and aluminum. There were 12 in set but I'm down to 8. These things are old.
Bravo1102
Visit this Community
New Jersey, United States
Member Since: December 08, 2003
entire network: 2,864 Posts
KitMaker Network: 171 Posts
Posted: Saturday, August 12, 2017 - 03:05 PM UTC
After you put on the wheel skirts and road wheels the springs are practically invisible. You really only have to clean up the bottom of the coil.

The ancient Airfix 1/76 scale Churchill had all of the springs separate too. The Hasegawa 1/72 Churchill and later Dragon Churchills have it all as one piece. Starting out in braille scale has its benefits. If you can do an assembly half again as small, 1/35 is easy.
Kevlar06
Visit this Community
Washington, United States
Member Since: March 15, 2009
entire network: 3,670 Posts
KitMaker Network: 527 Posts
Posted: Sunday, August 13, 2017 - 04:08 AM UTC
Nigel, Patrick,
The AFV club kit has all separate components-- including the springs. The Tamiya kit is the only kit that uses a side with everything in place, except the bogie wheels, which are attached through a hole in the suspension arm-- it makes for a very quick build, and frankly it isn't readily visible. I can't post photos, but a few years ago I built the Tamiya kit "Crocodile" version-- which is a Mark VII late war Churchill, with a round access hatch in the hull-- I got a little carried away and built a hull interior for it, and used Fruil tracks. If you're interested, send me a PM with your email and I'll forward some photos. I inherited my jewelers files too-- they came in a wooden tube, with six holes-- one for each file--- triangular, round, square, tapered half hemisphere, flat/rectangular and elliptical. My Dad was a machinist in a flour mill, before that he was on the USS Essex during WWII as an aviation metalsmith. I think he had the files since the 1940s and he used them primarily for fine cleaning work on motors and equipment-- he always called them "watchmaker" files, but I'm not sure that's what they were used for. The first time I ever saw him use one was to refurbish the glow plug on an .049 engine. They are steel, and about a 2" blade, with about a two inch handle-- so maybe 4" with a very fine tooth pattern. I've taken care of them for 40+ years now-- but recently hadn't used them for several months, and noted some rust forming on a couple, so I now keep them in a cheap file tube from Micro-Mark with a drop of sewing machine oil-- the wood case is shot. I also have a "not-so-cheap" set of diamond jewelers files-- but keep coming back to my "antique" files. I also have Dad's machinist ruler he had aboard ship in 1943, and a few other neat tools for miniature work-- they don't make them like that anymore.
VR, Russ
RobinNilsson
Staff MemberDirector of Member Services
KITMAKER NETWORK
Visit this Community
Stockholm, Sweden
Member Since: November 29, 2006
entire network: 6,693 Posts
KitMaker Network: 1,042 Posts
Posted: Sunday, August 13, 2017 - 01:13 PM UTC
Thin and narrow strip of metal(preferably brass or steel, aluminium and copper could be too soft). The edges/frame of a sheet of photoetch comes to mind ...
Fine grade sandpaper, wider than the strip, fold and superglue the metal strip in the fold. Result: small sandpaper file with a slightly rounded edge.

If you get one of these (jeweler's saw):
https://www.amazon.com/SE-81970SF-Adjustable-Jewelers-Professional/dp/B008CO8JZE
you can clamp the metal-sandpaper combo in the holders and use the sandpaper instead of a sawblade and avoid the super gluing.

One side of the spring coils is accessible without problems, the other side (inside the "arm") can be handled by threading the file-blade through the hole before clamping into the jeweler's saw.

Many years ago I bought "metal sandpaper", narrow strips of thin steel (0.2 mm or less) with a sandpaper structure on one surface. Clamped in the jeweler's saw it becomes a hybrid between a saw, a file and a sandpaper.
Holding it with four fingers in one hand is possible but requires a lot of dexterity and training.

One of these could also be used if the metal strip is long enough( fret saw or coping saw):
https://www.amazon.com/Eclipse-70-FS1R-Handle-Coping-Thickness/dp/B01D0CHOZI/ref=sr_1_3?s=hi&ie=UTF8&qid=1502697932&sr=1-3&keywords=fret+saw

Both of these saw types are very useful in modelling.
With a fine blade for metal they are excellent for cutting difficult sprue attachments where side cutters or knife will not work due to tight space or danger of stressing the part so that it breaks (delicate track links for instance).
Cutting out large holes is also easy.

/ Robin
 _GOTOTOP