Momo wheel spacer

[Sean Walsh]

Hi,

Bit of a long shot, but I’m after a steering wheel spacer.

 

I have a Momo boss and wheel but want to bring it out from the dash by about 10mm.

 

Anyone have one lurking that they’d like to re-home! 🤣

 

Thx

W

[Spacedoggy]

I have a spare 20mm black aluminium spacer (B-G).  Otherwise happy to 3D print a 10mm one?  I had to make one myself recently, so no problem to print another.

[Ian Kinder (Bagpuss) - Joint Peak District AO]

9 hours ago, Spacedoggy said:

I have a spare 20mm black aluminium spacer (B-G).  Otherwise happy to 3D print a 10mm one?  I had to make one myself recently, so no problem to print another.

A kind offer, but I'm not sure I'd trust a plastic part in this safety critical location.

[Spacedoggy]

3 hours ago, Ian Kinder (Bagpuss) - Joint Peak District AO said:

A kind offer, but I'm not sure I'd trust a plastic part in this safety critical location.

Apologies in advance if I'm straying into Tech Talk territory, but since I'm using a plastic spacer myself I thought it was important to ask why this could be a problem.  🙂

 

My issue was that, as supplied from Westfield, the MOMO team steering wheel doesn't fit onto the supplied boss without leaving a ~5-10mm gap if the centre horn is installed. Hence the reason I printed a spacer.  I'm using longer bolts which just pass straight through the holes in the spacer so that the steering wheel is still firmly bolted into the supplied metal boss.

 

I can't see why this would be an issue since the bolts are still doing their job but, as you say, this is a safety critical area so I don't want to take any chances.  Also, I think this approach has been taken by others so if it is a safety issue it would probably be good to make it known. 

 

@Sean Walsh - Devon & Somerset AO In any event, the 20mm aluminium spacer that was supplied with the MOMO steering wheel kit from Westfield is still available if you can live with an extra 10mm 🙂

[Kit Car Electronics]

I don't have a problem with plastic, but wouldn't personally be comfortable with a printed part as a spacer with any significant thickness for 2 reasons - compressive strength and temperature resistance, depending on material and density. Eg a PLA part with a low infill density would be structurally weak. For longer bolts, my preference is for 12.9 class Unbrako brand: https://www.westfieldfasteners.co.uk/BO_ScrewBolt_Unbrako_SHCsk_M5.html

[Dave Eastwood (Gadgetman) - Club Chairman]

Without knowing the engineering specs of the material used, it’s not 100% possible to say. Personally, though, even if it was a nylon loaded with carbon, I’d feel more comfortable if the bolt holes had steel or aluminum inserts/bushes that took the compressive load from the bolts. That way, even if the plastic were to relax or deform with time and heat, the wheel would not come loose.

 

As always with these sorts of things, the critical failure to consider isn’t the normal day to day use scenario, it’s the “what happens in an accident” situation, where you end up wrenching or pushing at the wheel with more than just your normal body weight; in a head on, for instance, even with full harnesses, unless you have them at race tightness, you will may well hit the wheel with a number of times your own bodyweight, the last thing you want is for the plastic to compress, wheel wrench free, and for you then to strike the end of the column on the rebound. 
 

If the material used is just an ordinary PLA, with all its heat issues and strength restrictions, then I wouldn’t have thought it at all suitable for the load bearing aspects.

[Spacedoggy]

Thanks for the feedback, very illuminating and constructive as always.  

 

@Kit Car Electronics I printed it in HIPS with solid infill, so it should have a reasonable compressive strength. Temperature, not so much though. Thanks for the bolt link!

 

@Dave Eastwood (Gadgetman) - Club Secretary Good call on the bushes, I'll look into doing this as a minimum if I can't get hold of a 10mm metal spacer with a suitable internal diameter that will accommodate the horn mechanism.  It's hard for me to consider the "accident situation" without feeling anxious about all kinds of stuff...

 

@Sean Walsh - Devon & Somerset AO Apologies again for hijacking your thread. 🙂

 

 

 

[Sean Walsh]

Hi,

No problem at all - actually a useful discussion!

 

I’ll check a few measurements this afternoon and will get back to you! 
 

Thx v m

Sean

[Sean Walsh]

@Spacedoggy

Hi,

I reckon 20mm is worth a try!

Let me know what you want for it and postage (if that’s ok with you?), to TA24 8DF

 

Thx v m 

W

[Spacedoggy]

@Sean Walsh - Devon & Somerset AOI’ve just discovered that B-G sell a horn button retaining ring for £5.99 that will allow me to use my 20mm spacer with my MOMO centre mounted horn button (which I've spent the best part of three months building a slip ring so that I can use, so to say I'm emotionally invested is an understatement). In view of the discussion above, I think this is probably my best route forward to avoid sleepless nights. 🤣

 

Unfortunately this means that the 20mm spacer is no longer for sale.  Really sorry for messing you around, but I promise I started with the best of intentions! 🙂 

 

If it’s any help BG-Racing sell a 10mm version for £24.99 10mm spacer

[Sean Walsh]

Outrageous! 😄

No problem at all!

 

 

[Dave Eastwood (Gadgetman) - Club Chairman]

On 10/04/2022 at 14:22, Spacedoggy said:

I printed it in HIPS with solid infill, so it should have a reasonable compressive strength. Temperature, not so much though.

 

Looking at the data sheets, it appears to be a slightly "bendier" equivalent to ABS, though not quite as strong. 

[Spacedoggy]

My gut feeling is that it would have been fine. However, as I'd never know exactly how it would behave in a critical situation I agree that I'm better off using the aluminium B-G spacer that came with the kit, at least now that I've found a horn button mount that will fit.  If only the kit had of included the correct horn button mount in the first place...  🤣

 

Anyway, thank you all for pointing out the risks that I rather naively failed to appreciate in the first instance. 🙂

 

 

[Dave Eastwood (Gadgetman) - Club Chairman]

The forces involved, in the very unlikely event of an accident can be extreme. (Borrowed pics from Si's build thread)

 

 

This is the resultant damage to the front end of a Westfield after a side impact to the NS front, while crossing a cross-roads...

 

 

Steel box section is torn and ripped like tissue paper, BUT, the chassis also did the job it was intended to and protected the driver, who walked away shaken but unhurt.

 

From the scuttle back, externally, there is little appearance of damage, (though get underneath, and you will see the chassis distorting progressively, soaking up the force, right back to the floor pans and transmission tunnel.

 

 

The drivers and passengers section of the cockpit are barely marked, internally. As it should be.

 

Having been in a tin top, in a front on collision, I never hit the steering wheel with any force, (retracting seat belts, and the airbags saw to that), yet I queried with the loss adjuster why the rim was bent - thinking the airbag might not have deployed properly.  he showed me how it was actually where I'd had hold of it in the impact, throwing my mass, under many g of deceleration, around with the wheel in a death grip.

 

IF, and yes, it's a big IF, in an accident, the plastic spacer can deform in any way, all the clamping load from the bolts holding the wheel in place will be immediately lost. If the wheel is being wrenched round at the same time, the force on the olts will magnify immediately, beyond what they were designed to hold. Possibly with no consequence, but then the possible worst case scenario doesn't bear thinking about.

[TAFKARM]

At least the fancy sock kept the shock clean.