Hornblocks choices.

[simonmoore]

I've just attempted to put together some of the high level fold up etchs for hornblocks & i am not impressed with them at all. I find the etch to be a little fiddly & the hornblocks are tight as my yorkshire pockets, I've followed the instructions perfectly & i'm just not pleased with the outcome. The brassmasters kit i have has some hornblocks with it which i think are a better design but i wondered what my choices were for hornblocks that work a little like the highlevel ones but without the fiddle & choice swear words.

Simon.

[Paul Willis]

I've just attempted to put together some of the high level fold up etchs for hornblocks & i am not impressed with them at all. I find the etch to be a little fiddly & the hornblocks are tight as my yorkshire pockets, I've followed the instructions perfectly & i'm just not pleased with the outcome. The brassmasters kit i have has some hornblocks with it which i think are a better design but i wondered what my choices were for hornblocks that work a little like the highlevel ones but without the fiddle & choice swear words.

Simon.

Hi Simon,

I know exactly what you mean about the HLK ones. However, that's *exactly* the way that I like them to be.

They are deliberately intended to be tight, so you can use a few light strokes of a fine file to fettle them out to fit exactly the bearings for each one. And then if you keep the bearing matched to that particular hornblock, then you will have a perfect sliding fit with no slop. Mine get marked with a cunningly code blob of paint so they don't go walkies.

And I was a bit doubtful about the "fold'n'click" assembly method of them, but once I'd got a couple done I was a convert.

Please do persevere with them, as I do think that they are amongst the best ones out there. Streets ahead of some of the olden day ones from the likes of Perseverance (of which I still have many sets in the drawer) which were all over the place, dimension-wise.

Cheers
Flymo

[essdee]

Hi Simon,

I know what you mean - I found them awkward at first, but am now a complete convert. What may not be obvious, if you do not have use of a craft magnifier light, is that the machining leaves ridges at the intersection of surfaces, including the bore for the axle. Not evident at a cursory glance, but they are there and effectively 'mop up' the close-fit that Chris has designed in to them. An over-large drill bit twirled in the bore will remove those edges and ease the fitting of the axle, and a gentle rub with a well-worn needle file should remove the remainder without scoring the machined rubbing surfaces. I have also used a worn scalpel edge to pare these edges back, including the etch cusp inside the bearing cut-out.

It's a faff, no doubt about it, but well worth persevering. Wash off all those parings, then polish the rubbing surfaces with a cocktaail stick in the Dremel/Minicraft, using Brasso or some such, then rinse the resultant clag off with meths and a soap wash. Once you get the knack, these bearings are as near to a delight to assemble, as I have encountered yet.

If you get to Leatherhead, do introduce yourself to Chris Gibbon at High Level - extremely helpful always.

Good luck!

Regards

Steve

[simonmoore]

I will have another go what did you use to make the slit in the bearing a little bigger ? Or should i sand down the guides to fit the slit?

Simon.

[essdee]

Hello again Simon,

Good man! I found that removal of the machining burrs either side of the slit gave me a fit, admittedly tight, on the etched guides, and that this soon eased with application of a mix of oil and Brasso, to give a silky sliding fit. I would avoid sanding anything - you will be creating a 'ploughed field' surface even with the finest emery -which you will then have to smooth down with Brasso ( a much finer abrasive) etc-by which time you will have a sloppy fit!

Put on Enya or whatever slows your pulse rate nicely, have a tipple handy, look out the window and go nice and easy. The first trial will seem to take ages - but will establish how much you need to remove. All I can say is it gets both quicker and easier with repeated experience.

Remember - once it's filed/polished off, you can't put it back! And what appears to us a polished surface, is actually full of high and low points. A single microscopic piece of emery/grit, not washed off, will sieze the whole assembly solid, so cleanliness is vital.

Regards

Steve

[Will L]

I've just attempted to put together some of the high level fold up etchs for hornblocks & i am not impressed with them at all. I find the etch to be a little fiddly & the hornblocks are tight as my yorkshire pockets, I've followed the instructions perfectly & i'm just not pleased with the outcome. The brassmasters kit i have has some hornblocks with it which i think are a better design but i wondered what my choices were for hornblocks that work a little like the highlevel ones but without the fiddle & choice swear words.

Simon.

I agree with all the above, the Highlevel hornblocks are the best available.

To start with, you should always need to dress down the sides of the axle blocks to be a good tight sliding fit in the horn guides. This is to ensure there is minimal side to side movement along the frames. Any axle block manufactured with tolerances such that they don't need dressing to fit is likely to provide the occasional example that is too loose and give you trouble. Use a 4 cut file till you get a tight fit and then polish until you have smooth movement. As Flymo said, match one block to one guide and keep them as a pair once matched.

On the Highlevel hornblocks there is also the fit between the slot in the axle block and the edge of the horn guide it slides on. If you got an early set you would have found that the slot in the axle block was cut that bit wider than the current ones. It is necessary that there is some clearance between axle block and horn guide, or the axles can't rock in the frames and may jam rather then slide up and down. I gather Chris got complaints about the amount of "slop" in his early production, and, to please the customers, the current ones have little clearance. In my view these complaints were misguided. Again you can polish them out it you want that perfect fit, but remember it is the presence of some clearance that is critical. A few strokes of a 4 cut knife edge file will do the job.

Will

[simonmoore]

Thanks Will for the advice,

Last night i spent a bit of time trying one out & from what i can see the actual bearing is being a pain. Where the bearing ring is seems to catch the side of the guides & does not want to fit. I'm going to the hobby holiday & he said to buy these hornblocks. I think i am going to get some replacements anyway because i have broken one & this ne is being a pain & just wait until i go to the weekend. I think i am going to buy some other ones too just for back up incase these are painful.

Simon.

[grovenor-2685]

Chris is guilty of raising expectations with his sales hyperbolae
This is what his website tells us

These 30-second hornblocks eliminate the four main drawbacks of conventional designs:
Simple fold up assembly
NO soldering involved
Instant fit of hornblock
NO fettling required

The various responses on this topic already suggest that the last line in particular is very optimistic.
Anyway knowing I had some of these in my unmade kit collection and a bit intrigued i went and pulled them out.
So first the etch: the advert and the real thing, looks OK

webhorn1.jpg

Picture15.jpg

So what do we do?

webhorn2.jpg

Picture17.jpg

So far so good, then

webhorn3.jpg

Picture18.jpg

and

webhorn4.jpg

Picture19.jpg

So all nicely folded up as advertised.

webhorn5.jpg

Picture24.jpg

OK block slides in but rather tight, I haven't tried it yet but IMHO it needs a bit more than just a polish, definately what I would describe as fettling. But as others said above, better tight than loose as its much easier to file a bit off than put metal on.

Now the bearing itself, as you noted an axle enters from the inside but won't go through.

Picture21.jpg

Why not?

Picture20.jpg

However a quick twirl with a round file (or an oversize drill as mentioned earlier sorts it)

Picture22.jpg

Picture23.jpg

On the ones I have the slot in the bearing is plenty wide enough to allow for the required tilt so its just the horn cheeks that need fettling.

Picture27.jpg

webhorn6.jpg

Regards

[jon price]

So any ideas from anyone who has used these hornblocks with springs as opposed to CSBs?

Jon Price

[simonmoore]

Jon when i purchased my blocks of highlevel he told me he is bringing out some tags to solder to the hornblocks so you can do the CSB system. I am going to perservere with these blocks & get them to work i just need a little more paitents

Simon.

[grovenor-2685]

Jon when i purchased my blocks of highlevel he told me he is bringing out some tags to solder to the hornblocks so you can do the CSB system.

See
http://www.clag.org.uk/pics/beams/high-level-CSB-jig-and-hornblock-system.pdf
Regards

[Mike Garwood]

Hi

I've been using sprung hornblocks from Gordon Ashton for a number of years. I saw them in MRJ alot of years ago. Sent for a set and have not really looked at anything else since. I am contemplating a 94xx with CSB's, but thats' at a future date!
So...the etch

The etch from G Ashton.jpg

And the finished article.

Finished article.jpg

Drill out the mouse ears with 0.5mm drill, add the the corner of the bearing - with 224/188 solder, you really don't want these to fall off when installing into your chassis! Next, fold up the side with the tab and slot and solder in, add the other side. I use a block of wood that's the same width as my choosen bearing - MJT. Mr Ashton did specify Perserverance bearings, but as I can't find a supplier of these anymore...Polish the sides of the bearing. Finished! Add wire of the desired width, it's not difficult to change diameters of guitar wire with a little foresight in placing the spacers in your chassis. It's also easy to adjust the height as Gordon gives you plenty of choices down the side of the 'wings', he also gives a wide or narrow option. To be honest I've only ever used the narrow option.

Cheers

Mike

[grovenor-2685]

OK yesterday I tried assembling a couple of the High Level hornblocks and reached the point where the sliding fit was to tight and needed fettling.
This evening I have had a short session of fettling to see what is involved.
There are two possibilities where the tightness could be coming from.
1. is the horncheeks that run against the side of the bearing, this is the intended rubbing area and needs to be a smoooth sliding fit.
2. is the turned area at the bottom of the slt in the bearing which could be binding if the edges of the hornguide bottom in the slots. This is not intended and there should be clearance here

So the first thing is to check for 2 and get rid of any binding. The bearing has two turned areas, the bottom of the slot and the ring at the back. so far as I can tell from inspection (its hard to measure in the slot) these appear to be of the same diameter, so if the ring at the back is a free fit so will be the slot.
With the two i have worked on the first had good clearance, the second was tight, so on this second one i filed a little off the inner edges of the horblock enough to give a loose fit on the ring. These edges are only there for lateral restraint and the edge is not involved in the longitudinal play so it doesn't matter if you overdo it a bit.

Picture30.jpg

That done the bearings are still tight so a bit more work is needed. Its difficult to remove material from the horncheeks in a controlled manner so just check they are properly at 90 degrees and deburr the edge.

Before going further mark up the sets so you can keep them together and in the case of the bearings mark the top so you always put them the same way up.
You can use dabs of paint as suggested by Flymo earlier, I used my centre punch to place dots on top of the bearings, one dot and 2 dots, then filed little notches on top of the hornblock to correspond.

Picture31.jpg

Now its neccessary to take off just a little metalfrom the sides of the bearings until the fit is just loose enough, they should be able to drop out of the hornblock slots by their own weight without you being able to feel any slop.
For this you don't want to use a file as you want to keep a very smooth finish and the amount to remove is very little. use very fine emery or, as I did, the smooth side of a carborundum sharpening stone, just a couple of rubs on each side and try it in place, then again till you get the desired fit. Should only need 2 or 3 rubs. Once it seems correct clean it up with a fibreglass brush.

Picture28.jpg

When finished I also put temporary retaining wires in mine to keep them together until i need them.

Picture32.jpg

Perhaps this process is what Chris means by 'polishing' as distinct from 'fettling', my feeling is that it goes a bit beyond polishing which is what I would do with the fibreglass brush and was not enough in this case.

But hey, this little topic has got me two hornblocks started which means that i have actually started the 04 chassis kit.
Regards

[allanferguson]

This has been an informative discussion, and I have been grateful for the inputs provided. As a relatively recent convert to CSB suspension one issue I have found (and since no-one has dealt with it, it presumably hasn't been a problem for many) concerns the width available for the gearbox.

With "old fashioned" compensation the gearbox was normally on a fixed axle, which therefore did not need hornkeeps and axleboxes, and the width available was never an issue. With the various systems of axleboxes available, most seem not to have the width specified, but by measurement I find that most seem to leave a space between the axleboxes of 10.0 -- 10.5 mm, with frames 14.5 -- 15.0 mm apart. Now the High Level gearboxes which seem to be generally preferred have a width across the axle specified at 8.7 -- 11.8 mm (apart from the slimliners), which doesn't leave much to spare, especially given my level of manufacturing tolerances.

Incidentally this was how I came to use Brassmasters bearings in my frames shown on the CLAG website, but adapting them for CSB's lost me some of their slimness.

Is this not a problem for anyone else, or how do you deal with it?

Allan F

[Jol Wilkinson]

I've just seen this topic, after returning from S4Uum helping John Redrup on the London Road Models stand for the weekend.

I was interested and a little surprised to read Simon's comments on the HL fold up hornblock guides. I had been led to believe, partly by a well known writer/author/modeller and by others' comments that these were the bees knees and could be assembled without any fettling, something that was critiscised on the LRM cast brass hornguides - although not difficult to do and which which ensures a good operating tolerance.

So, for those like Simon who want a hornblock system with a separate guide (rather than the Brassmasters bearing running directly in the frame type), they might like to consider the LRM version. The instructions are downloadable (if that is a proper word) from http://www.scalefour.org/londonroad/components.html on the Society's very own website.

Incidentally, LRM also introduced a CSB adaptor etch for it's hornblock bearings, sometime before HL.

Jol

[essdee]

Allan,

I had exactly that issue when using the HL axleboxes in a GIbson P4 chassis. Admittedly I had shaved the P4 spacers a bit to allow more room for sideplay on curves, but I think it would have been tight even otherwise.

I obtained clearance for a wide HL gearbox (ie one with a grub screw fixing for the drive gear, I do not like to rely on Loctite), by running a file around the spring tag's locating boss on the axlebox, thus narrowing the axlebox a tad, as well as ensuring any machining burr is removed. After soldering the tag in place, I ground off the excess protrusion of the boss, and polished the smoothed surface. THis procedure will move the hole for the spring wire out of alignment with those of the other axleboxes, probably by a non-critical amount. To be safe, I mis-used a drill bit to enlarge this hole horizontally to compensate for the thinned axlebox effect.

Even with my narrowed P4 spacers, it was not a great amount to be removed from the relevant axleboxes, so you ought to be OK with a 4 or 6 coupled chassis. As a first resort if clearance is tight, simply grind off the excess boss protruding from the spring tag face after soldering - this will occur even with a non-thinned axlebox.

Hope this works for you, my resultant chassis is the smoothest I have built and I am now 'sold' on the High Level system for future build. If any problems, Chris Gibbon is also extremely helpful.

Regards

Steve

[simonmoore]

With some re-newed enthusiasm i have had another go with the highlvel blocks & result I've managed to get it working a little better using Keith's great images & instruction of how he has done his i have got my first one working. I still need to make is a smooth slide fit i guess a little polishing & some deburring & we should be working fine. Perserverance is the key & be in the right mood to do it. Now where did she put that bloody brasso??

EDITED

First bearing now completly working it has free running of the guides & as said above i am now sold on the idea plus with the CSB system being released with tags to fit i think this will make hornblocks simple for even the newbie like myself.

Simon.

[essdee]

Congrats Simon -really pleased that it has worked for you! I am sure you will find it easier with subsequent ones.

I think this thread again demonstrates just how useful the web is for giving help and encouragement to newcomers to the field as assorted 'old lags' (if you will excuse the term, gents) can chip in different aspects on how they made progress.

I found Keith's close up pics absorbing, showing clearly how rough is the 'as-received' surface of typical good-quality components. Imagine the energy threshold to be overcome in getting such mating surfaces, under a typical load of lead weight, to start moving, let alone roll freely.

Happy polishing! But do remember to flush out the resultant oil/Brasso/gunge sludge afterwards. If left in situ, it makes a superb 1:76th scale cement.....

Regards

Steve

[simonmoore]

My bearing hasnt got any polish what so ever on it i used a file to clean the surface off for the bearing to fit & filed back the hornguides just enough for free floating of the bearing. Hopefully it is ok & will work well i guess time will tell. I am going to order a nice stock of these from highlevel so when i go on my hobby holiday weekend i will be able to see if my ork has paid off or wether i have to re build them all ( hopefully not ). Theres a little fraction of sideplay but it is a migeys whisker which i figure wont be anything major.

Simon.

[Russ Elliott]

I was interested and a little surprised to read Simon's comments on the HL fold up hornblock guides. I had been led to believe, partly by a well known writer/author/modeller and by others' comments that these were the bees knees and could be assembled without any fettling, something that was critiscised on the LRM cast brass hornguides - although not difficult to do and which which ensures a good operating tolerance.

I think Jol has good cause to be a trifle miffed over this show of possible favouritism in the media. The point is that the initial (2006) HL guides were fractionally loose in holding the 4.8mm block faces, and hence the 'fettle-free' accolade. Those initial guides were in 0.4mm material, whereas the production ones are in 0.3mm. This change, along with other comments from initial users, necessitated changes to the slot width on the block drawing and tweaks to the guide artwork, and with etching not being an exact science, it is difficult to judge whether there is a consensus on whether Chris has now gone a little bit too far in the 'tight direction', and to be fair, he and other manufacturers will always be torn between those customers expecting a 'fettle-free' product and those customers who see virtues in a hornblock system that does require some fettling and polishing.

My personal view is that having got a block/guide combination fettled/polished to a stage (off-chassis) that the block is a smooth but still slightly tight fit in the guide is probably a good time to set the guides in the chassis frame (with rods on axle jigs). A slight tightness of bore on axle material is also no bad thing either at this setting and alignment stage. These two areas of initial tightness are helpful in my view in holding the blocks and the axle jigs exactly where they should be, and where (in the the absence of bespoke Avonside/Hobby Holiday contraptions) one always needs two pairs of hands to stop things slopping about too much if those fits are loose. Subsequent to fixing the guides in the frames, further brasso polishing of block and guide and concentric reaming of the block bore can take place to one's heart's content to ease the fits into silky ones - this easing will not affect the essential alignment of rod to frame axes.

[Russ Elliott]

Mike - nice to see the GA units again, but I understand they are not available now.

[Mike Garwood]

Russ

Took delivery Saturday of another batch for more engines. So, still available.

Mike

[Russ Elliott]

Thanks Mike - good news! (I'm scratching my head trying to remember who told me they were no longer available - brain's not working today - post-Scaleforum dizziness.)

[Will L]

The following appeared on E4um with a request that it should find its way here. seemed a resonable and usful request to me. So heretis

Hi all, just heard from a friend that there's been some discussion on the Scalefour Forum regarding the use of Highlevel hornblocks. Now, I'm not a contributor to that forum but I do follow it. So, if I could make some comments through this forum perhaps someone could quote them on S4forum. As a trial builder, problem solver and sounding board (Chris's words) to Chris at HL. (along with a few others) I've been involved from the beginning with his hornblocks and the first trials showed that the tolerances in the square stock for the bearings and the etching material could vary quite a bit (relatively) so the fit could be variable from tight to overly slack, now a tight fit can be eased with a quick stroke of a file or emery but a slack fitting hornblock could be detrimental to the smooth running of the finished loco. So, what to do? should we leave it at that or do we adjust the sizes so the hornblock 'at worst' would still be a good sliding fit and for some the need for a quick rub to get a good sliding fit, I admit, I pushed for the latter.
The "30 second hornblock" expression was coined by a reviewer and has been used sometimes by Chris himself and if all things being equal regarding the above paragraph then yes I've assembled some hornblocks in 30 seconds..... I've just been through to the workshop, picked up an etch, rubbed a file along the edge that the slot in the bearing runs on, folded the etch and bent the horn cheeks carefully to 90 degrees, picked up a bearing at random tried it, a little tight, two stokes of a fine file and a quick rub on an oil stone and Roberta's yer uncle, a nice sliding fit, the bearing stays in the etch but drops out when you shake it. Not too slack nor too tight. The time taken? - exactly two minutes. A bit longer than 30 seconds yes, but it ensures that the suspension works as it should with no tight spots or worse, slack hornblocks. On this last note I personally like to finish the bore of the bearing with a reamer so that the axles are the best fit possible, axle diameters can vary a few thou and if the axle is too slack that is as bad as slack hornblocks to the final running and indeed the longevity of the mechanism.
Okay I've been assembling these hornblocks for nearly five years now and, Jol, that includes the CSB spring tags that I suggested to Chris at the beginning. Ted Scanell even wrote about them on the CLAG website in June 2006. They have been a freebie with the hornblocks if you asked for them since that time. The latest spring tags are even more useful as they have multiple holes in them so you can mount the CSB or independent springs at variable heights to avoid various bits in the chassis frames or even mount them underslung.
One contributor asked about fitting a gearbox with hornblocks, try this, fit a Highlevel hornblock inside out, that is, fitting it on the inside of the chassis but with the bearing and horn cheeks going through the chassis, you can then if required slim the bearing down to get the back to back clearance and gearbox clearance. I've even done it on a OO chassis!!!! A photo of how I did it is on the CLAG website, just click on the CSB gallery.
I hope this doesn't seem to come on too strong but being an engineer I prefer to "finish to fit" as it used to say on the drawings.

Regards.
Dave Franks.

[Jol Wilkinson]

And here is my response to Dave,

Dave,

thanks for pointing out that that HL had CSB adaptors (as I call them) available from 2006. I wasn't aware of that as I don't use HL products, but I do know that quite a few people bought the LRM items stating that they wanted them to use with HL hornblocks. Hence my erroneous assumption that Chris Gibbons didn't make them until recently.

Looking at my CorelDraw artwork for the LRM CSB's, I notice that the original drawings were created on 7 December 2005, but I don't recall when they were first put into production.

Jol