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RTR Models Screws Wearing-out


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 Hi there.

 As we know from time to time our models need a bit of maintenance. Recently my Bachmann 8750 Class has started to squeak. I have had it for a number of years, and like 95% of my models I have never opened it up before. In the past I have had to do a bit of work on one or two loco, but when unscrewing them I found that some Screws seem to become worn very quickly indeed (even after one use). Some of the screws are in there very tight and need a bit of force to budge too. 

 Has anyone else found this issue? Could it be metal or is it the screw drivers I am using (I have a set of cross and flat head screw drivers in a number of sizes, they seem to fit the screw heads fine). Any info on this would be of great help. 

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Could be any one of the following:

 

Cheap screws.....replace with better ones of the same size, ebay is your friend.

Cheap screw-DRIVERs, wrongly shaped heads....replace with decent quality ones.

Over-tight screws....once replaced, do not retighten as much.

Using the wrong screwdriver....could it be a very small Posi-drive, NOT Philips?

No proper threads...resulting in over much force needed for a small screw.

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Could be any one of the following:

 

Cheap screws.....replace with better ones of the same size, ebay is your friend.

Cheap screw-DRIVERs, wrongly shaped heads....replace with decent quality ones.

Over-tight screws....once replaced, do not retighten as much.

Using the wrong screwdriver....could it be a very small Posi-drive, NOT Philips?

No proper threads...resulting in over much force needed for a small screw.

Thanks for the info Jeff. Will keep an eye out for some good screw drivers. Any recommendations?

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No recommendations as such, but look for the established industrial suppliers or the better known tool suppliers at shows. Typically a 5 set of the smaller cheapo screwdrivers will cost about £5(ish). Quality ones will be nearer £20 and well more than that for some.

 

Many years ago I got a set of 5 small drivers of the then astronomic price of about £5/£7, cheap sets were then under £1.00. They have solid brass handles and steel blades and have served me well and still do.

 

Oh yes buying quality tools and most importantly, looking after them always pays off in the long run. That's not to say I don't also have a 'rough' work set of cheapo ones around.

 

Good hunting, it could be expensive (but worth it!)

 

John

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As above, cheap tools are not cost-effective.

 

One of the problem with Philips style screws is using a slightly too large, or slightly too small driver. It almost instantly renders the screw biting surfaces null.

 

The screwdriver should be a good snug fit.

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And remember that cross head screws are of different types. In simple terms:-

 

Philips screws have a simple X slot. And if you look at the screwdiver tip, the point angle is a bit sharper, (I'm guessing about 60 degrees total), than...

 

Pozidrive screws. I'd guess the point angle is about 90 degrees total, ie 2x 45 degrees either side of the shaft. This is important; if you use the wrong (ie the other) type in a screw head, you will damage the head. Also the Pozidrive has not only the X slot, but a  smaller + slot as well, giving a total of 8 slots.

 

In theory that is it, get the right type, and then the right size of screwdriver.

But, when manufacturing moved out east, probably Japan, many years ago, they seemed to develop their own brands of these types. It seems to have got easier over the years though, probably a combination of China, and mobile telephones etc, as they seem to have standardised them a lot better. Though I am not a fan of cheap tools, (pay cheap, buy twice), you can find correct size screwdrivers in some cheaper shops. However on the High St, Maplins is probably a better choice, or a Computer Fair. But traders at our ehibitions certainly stock them.

 

Stewart

 

Stewart

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And remember that cross head screws are of different types. In simple terms:-

 

Philips screws have a simple X slot. And if you look at the screwdiver tip, the point angle is a bit sharper, (I'm guessing about 60 degrees total), than...

 

Pozidrive screws. I'd guess the point angle is about 90 degrees total, ie 2x 45 degrees either side of the shaft. This is important; if you use the wrong (ie the other) type in a screw head, you will damage the head. Also the Pozidrive has not only the X slot, but a  smaller + slot as well, giving a total of 8 slots.

 

In theory that is it, get the right type, and then the right size of screwdriver.

But, when manufacturing moved out east, probably Japan, many years ago, they seemed to develop their own brands of these types. It seems to have got easier over the years though, probably a combination of China, and mobile telephones etc, as they seem to have standardised them a lot better. Though I am not a fan of cheap tools, (pay cheap, buy twice), you can find correct size screwdrivers in some cheaper shops. However on the High St, Maplins is probably a better choice, or a Computer Fair. But traders at our ehibitions certainly stock them.

 

Stewart

 

Stewart

 

 

No recommendations as such, but look for the established industrial suppliers or the better known tool suppliers at shows. Typically a 5 set of the smaller cheapo screwdrivers will cost about £5(ish). Quality ones will be nearer £20 and well more than that for some.

 

Many years ago I got a set of 5 small drivers of the then astronomic price of about £5/£7, cheap sets were then under £1.00. They have solid brass handles and steel blades and have served me well and still do.

 

Oh yes buying quality tools and most importantly, looking after them always pays off in the long run. That's not to say I don't also have a 'rough' work set of cheapo ones around.

 

Good hunting, it could be expensive (but worth it!)

 

John

 

As above, cheap tools are not cost-effective.

 

One of the problem with Philips style screws is using a slightly too large, or slightly too small driver. It almost instantly renders the screw biting surfaces null.

 

The screwdriver should be a good snug fit.

Thanks Guys. I'm displaying at a Model Exhibition very soon, so hopefully there will be a stall there, but if not I'll look around on the high st. I'll know not to go cheap this time  :declare:

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And remember that cross head screws are of different types. In simple terms:-

 

Philips screws have a simple X slot. And if you look at the screwdiver tip, the point angle is a bit sharper, (I'm guessing about 60 degrees total), than...

 

Pozidrive screws. I'd guess the point angle is about 90 degrees total, ie 2x 45 degrees either side of the shaft. This is important; if you use the wrong (ie the other) type in a screw head, you will damage the head. Also the Pozidrive has not only the X slot, but a  smaller + slot as well, giving a total of 8 slots.

 

In theory that is it, get the right type, and then the right size of screwdriver.

But, when manufacturing moved out east, probably Japan, many years ago, they seemed to develop their own brands of these types. It seems to have got easier over the years though, probably a combination of China, and mobile telephones etc, as they seem to have standardised them a lot better.

Manufacturers of equipment, invent new screw types so purchasers of said equipment can't repair it themselves. Shortly afterwards, other Chinese manufacturers add these drivers to their sets, so you have to go out & buy another complete set. So repeats the cycle!

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I'm sure all the advice above about buying good tools is very sound. However, and this applies especially to Bachmann, it seems to me that the screws are of very poor quality metal, and this explains my the heads spoil so easily. One trick is to slightly sharpen your screwdriver, so that it sits further into the head of the screw - a tip given to me by a Bachmann rep at a Show! The practice of self tapping metal screws into plastic also seems to me pretty shoddy, especially when the screws are overtightened in the factory, making unscrewing without damage very difficult.

 

Of course all of this is to keep the price down, a subject discussed at length elsewhere on RM web. However if you compare the construction quality of our 4mm RTR offferings with the likes of Fleischmann N in Germany you will understand what I mean!

 

John.

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Japanese screws seemed to have a head that was neither Phillips or Posidrive*. Either would damage the screw head. I've had to drill the wretched things out in the past....

 

Pound shops have a small  knurled metal screwdriver with mulitiple bits stored in the handle**, which I've found will shift most of these screws. It seems quite decent for a cheap tool. There is also a wrench version with more bits.

 

* I seem to recall the angle was shallower, so the drivers didn't fit properly with the inevitable result if tightened too much.

 

** QD also have them but at twice the price.

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 Hi there.

 As we know from time to time our models need a bit of maintenance. Recently my Bachmann 8750 Class has started to squeak. I have had it for a number of years, and like 95% of my models I have never opened it up before. In the past I have had to do a bit of work on one or two loco, but when unscrewing them I found that some Screws seem to become worn very quickly indeed (even after one use). Some of the screws are in there very tight and need a bit of force to budge too. 

 

Are you sure it's the screws wearing and not self tapping screws being over tightened and chewing up the plastic/mazak that they are screwed into?

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Another related problem is that screws being installed far too tight during manufacture, and being almost impossible to remove without damaging. I've come across this in Bachman and the Great British Locomotives series, just getting the loco off the plinth was a half hour job on one of these !!.

 

As mentioned, a range of good quality screwdrivers (and replacement screws) is a must.

 

brit15

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No recommendations as such, but look for the established industrial suppliers or the better known tool suppliers at shows. Typically a 5 set of the smaller cheapo screwdrivers will cost about £5(ish). Quality ones will be nearer £20 and well more than that for some.

 

Many years ago I got a set of 5 small drivers of the then astronomic price of about £5/£7, cheap sets were then under £1.00. They have solid brass handles and steel blades and have served me well and still do.

 

Oh yes buying quality tools and most importantly, looking after them always pays off in the long run. That's not to say I don't also have a 'rough' work set of cheapo ones around.

 

Good hunting, it could be expensive (but worth it!)

 

John

Interestingly  I  bought  a  couple  of  sets  of  small screwdrivers ( 6 drivers per  set)  about  10  years  ago  from  Mold  market ( the  tool stall  for  £1.00 per  set.

 

They  have  been  well used over  the  years  and  are  still in  use   to  this  day!  ( Also  bought  some  fine  nosed  miniature  plliers for  £1,00  a  pair  htese  are  still in regular  use)

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I sometimes find it easier to cut a slot in the screws with a rozor saw or small hacksaw and use a standard flat blade screwdriver

 

Edit:

 

Another option if its not a countersunk one is to file some flats on the head and treat it like a bolt

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I sometimes find it easier to cut a slot in the screws with a rozor saw or small hacksaw and use a standard flat blade screwdriver

Yes changing it to a flat head if possible is a good idea, I used to have a supply of left hand drill bits, often using a drill in reverse would do the job using one.

Screw extractors also a good idea but its finding a small enough one, and you have to pre-drill the screw head.

Sometimes the only answer is to simply drill the head off (especialy if its countersink) then remove whats left of the screw with pliers after dissasembly.

One needs to understand that the manufacturer does not want us to be able to strip it anyway!

 

Paul

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