Fixing axles to wheels

What clearance should there be wheel and axle for loctite/truloc? I have searched forum with some success but would like peoples advice please

Mick

Personally I use a good running fit in the wheel, perhaps a thou or so larger than the axle, then use Loctite 601 (Mainly because I have plenty) brushed on to both mating surfaces to ensure a good cover and then assembled.

This works well when quartering as you have a few seconds to ensure correct alignment before the loctite sets.

Once assembled, for belt and braces I drill in between the axle and wheel and insert a pin also loctited in.

Hope this helps

Regards

Thanks FMES, I suppose if its too close a fit then the loctite would be squeezed out on assembly I'm wondering what the max clearance would be, the insertion of a pin sounds like a good idea

Thanks again

Mick

Close fits will give maximum strength. I prefer a close push fit for accuracy. As you can see there's barely any difference from zero to three thou (this is from Henkel's literature).

Loctite 601 is a good choice as it's high-strength, low viscosity (good for small gaps) and its fixture time is long at 25 minutes.

Loctite 603 is another good option as it's tolerant of light oil/grease contamination (think dirty fingers not dipping in neatcut) but is thicker than 601 and fills gaps up to 5 thou, (~0.13mm), fixture time of 10 minutes (full cure time is 24 hours) and high shear strength.

Oddly my 2017 technical guide to Henkel products (which runs to about 300 pages) doesn't cover 601, but it's certainly still available.

Neil

Thanks Neil, I have 3 thou clearance so hopefully that'll be ok, I do use truloc but will perhaps use the ones you suggest

Mick

On the little 0-4-0 I had a tad under 2 thou and used Loctite 638, I,ve not test run it yet but I think it has fixed really well.

Ron

Truloc products are fine, just choose the right one.

I prefer to make a shallow (0.003 max) groove between good fitting ends that should be kept as small as possible in widths.

The good fitting ends ensure that the parts are located as accurately as possible and the reduced centre portion ensures that the adhesive is the corrrect thickness and not eccentric.

Brian

Truloc 268 or 271 seem appropriate

Mick

Brian (BDH) above refers to what is sometimes known as the 'cotton reel' method, which is highly recommended.

I have always used 601 loctite for wheels to axles, but I think that 638 is regarded as better if the axles get hot due to being under a firebox on a loco. I have not the slightest idea whether 601 is still available, or whether 638 has been re-numbered. I used 601 because I could get a bottle free from Canton Works stores if I explained what it was for.

The last time I built a miniature loco with an axle underneath the ashpan it had press fits for the wheels.

Cheers,

Julian