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I havn`t posted on this subject for a while,i was trying to decide wether to fit Slaters sprung axleboxes to the front driving axle due to the problems of getting all the wheels in contact with the track,very difficult i found with a rigid chassis.Well,the  sprung axle boxes have been fitted,no fun on a partially built chassis,getting the centre height correct & the coupling rod spacing.Dang me,the centre drivers still don`t touch the track so the top of the frames are level so it looks like ive got to remove the centre bushes,file the holes out a bit lower & refit the bushes,thank goodness for a 100w soldering iron.I might even finishthe chassis one day.

 

                             Cheers,Rsy

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I havn`t posted on this subject for a while,i was trying to decide wether to fit Slaters sprung axleboxes to the front driving axle due to the problems of getting all the wheels in contact with the track,very difficult i found with a rigid chassis.Well,the  sprung axle boxes have been fitted,no fun on a partially built chassis,getting the centre height correct & the coupling rod spacing.Dang me,the centre drivers still don`t touch the track so the top of the frames are level so it looks like ive got to remove the centre bushes,file the holes out a bit lower & refit the bushes,thank goodness for a 100w soldering iron.I might even finishthe chassis one day.

 

                             Cheers,Rsy

You might find that the centre axle is a little high. Rigid 6 wheel designs often (usually?) have the centre axle higher than the leading and trailing axles.

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Hi David,yes i think it`s better to build it as an 0-4-0 as regards to thecentre & rear axle so tomorrow,it`s out with the scribing block & surface plate(milling m/c table)& check that the top of the frames are level before making any alterations to the centre axle bushes with the leading & trailing wheels fitted.

 

                                    Ray.

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Hello Ray -

I fitted Adjustable Four Track / now Gladiator I think  hornblocks to the leading 2 axles on my Fairburn - it seems to work...the tapped hoes in the top take 12BA screws that can then be adjusted to set the ride height. Springs can be fitted over the screw to bear on top of the bearing.

 

 

Regards

Tony

 

post-6972-0-58272900-1432540854_thumb.jpg

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Hi Tony,I wish i had seen those axleboxes before.I did toy with the idea of filing a bit off of the spring locating peg on the Slaters boxes but this may make the front of the loco lower than the back.I think i will have to have the centre bearings out of the frames & file the hole a bit lower & resolder the bearings.Incidentally,while on the subject of frames,i am using Slaters plunger pickups & discoverd that the centre wheel p/u fouls the motor so has to be be redrilled in a different position.

 

                      Ray.

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Hi Ray

Without some photos it is a little unclear as to what you are up to! However, I am assuming you are using the Slaters plastic axle box horn guides with square brass bearings, or of course you may be using the fold up metal ones. Whatever type the 'best practice' is to fit the motor/gearbox to the rear axle in 'fixed' bearings. This will give you the correct ride height, at the rear.

Using horn blocks on the middle and front axles, along with their springs, then does not need to be that accurate in the vertical plane as a small spacer fitted across the chassis above the front axle with a soldered nut underneath and a bolt and locking nut passed through from the top , can be used to bear on the centre of the axle and adjust the ride height at the front. The springs on the middle axle will take care of it.

 

In respect of horizontal location of the middle and front horn blocks, the rods must be used to locate them in the correct place. There are a number of proprietary jigs to help you do this but, if you are not a prolific builder, and don't want to spend money on them, a cheap and easy solution is to open out the crankpin holes in the rods so that the Slaters wheel retaining screw will just fit through. Then using the axles located through the bearings, and fitted to the loose horn blocks in the chassis, screw the rods to the axle ends. Result, perfect alignment of axles, rods, bearings and horn blocks. A dab of solder or glue and you are done.

 

I hope this helps

Regards

Sandy

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Hi Ray

Without some photos it is a little unclear as to what you are up to! However, I am assuming you are using the Slaters plastic axle box horn guides with square brass bearings, or of course you may be using the fold up metal ones. Whatever type the 'best practice' is to fit the motor/gearbox to the rear axle in 'fixed' bearings. This will give you the correct ride height, at the rear.

Using horn blocks on the middle and front axles, along with their springs, then does not need to be that accurate in the vertical plane as a small spacer fitted across the chassis above the front axle with a soldered nut underneath and a bolt and locking nut passed through from the top , can be used to bear on the centre of the axle and adjust the ride height at the front. The springs on the middle axle will take care of it.

 

In respect of horizontal location of the middle and front horn blocks, the rods must be used to locate them in the correct place. There are a number of proprietary jigs to help you do this but, if you are not a prolific builder, and don't want to spend money on them, a cheap and easy solution is to open out the crankpin holes in the rods so that the Slaters wheel retaining screw will just fit through. Then using the axles located through the bearings, and fitted to the loose horn blocks in the chassis, screw the rods to the axle ends. Result, perfect alignment of axles, rods, bearings and horn blocks. A dab of solder or glue and you are done.

 

I hope this helps

Regards

Sandy

 

 

Thanks Sandy,i will post some pics.The horn guides are Slaters cast brass,i think i now have success with removing the centre bearings,fililing the hole slightly lower measuring from the bottom edge of the frames with a digital caliper & resoldering the bushes back in,all wheels now touch the rail.I think that i was expecting the wheels to touch by using the holes supplied in the frames,i also think that i now realise that as built,thay actually build as a 2-4-4 as regards to the centre wheels touching the rail,ala.Hornby dublo!!.My normal scale for building sprung chassis is in 5" gauge,somewhat heavier with sprung axleboxes on all axles.

 

      Cheers,Ray.

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This is what i was up to.Retrofitting sprung axleboxes to a part built chassis involved an expensive Warco milling m/c,lots of measuring for centre lines & filing,whilst making sure that the wheel spacing for the coupling rods was spot on & to my surprise & satisfaction,they went straight on with no binding.This job i discovered was not for the faint hearted.I think if i built another kit,i would fit sprung axleboxes to the front drivers at least before i fitted the stretchers :yes: .

 

 post-4249-0-46869600-1432837701_thumb.jpg

 

 

                             Ray

 

 PS.Forgot to mention the redrilled holes for the centre plunger pickups,as original,they fouled the motor gearbox.

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This is what i was up to.Retrofitting sprung axleboxes to a part built chassis involved an expensive Warco milling m/c,lots of measuring for centre lines & filing,whilst making sure that the wheel spacing for the coupling rods was spot on & to my surprise & satisfaction,they went straight on with no binding.This job i discovered was not for the faint hearted.I think if i built another kit,i would fit sprung axleboxes to the front drivers at least before i fitted the stretchers :yes: .

 

 attachicon.giffairburn frames.jpg

 

 

                             Ray

 

 PS.Forgot to mention the redrilled holes for the centre plunger pickups,as original,they fouled the motor gearbox.

I would of sprung the middle axle, you will have to load the bogie to stop it falling on its nose. which in turn means you are running a big 4-4-0. You have lost at least a 3rd of the adhesion.

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It should be ok,Slaters axleboxes have a spring retaining peg which if set up correctly,the axlebox in nomal use sits hard against this peg so that in use,all wheels contact the rail!.

 

 

                                 Ray.

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It should be ok,Slaters axleboxes have a spring retaining peg which if set up correctly,the axlebox in nomal use sits hard against this peg so that in use,all wheels contact the rail!.

 

 

                                 Ray.

I know they have the peg but if it rides on the peg it is no better than a rigid chassis and you will have no more than 4  wheels on the rails and probably nearer to 3. If you spring the middle up and down you get between 5 to 6 on the rails. 3 point compensation, all axle springing and CSB's give you 6 all the time. Its seems a lot of effort you have put in for a result no better than a rigid chassis.

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I see what you mean,ideally,the box should not sit on the peg,in fact, i thought about removing some of it & leaving a part of it as a spring locator.0 gauge kits are certainly a steep learning curve.Mind you,at least i can lift it which is more than  can say about the chassis for my 5" gauge 2-10-0 BR Austerity loco!!! :O

 

 

                                    Ray

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