Vibrating Bench Grinder

[John15]

I have recently bought a 150mm £50 bench grinder. I get quite bad vibrations from it and I'm wondering if I've mounted it on an unsuitable base. I've screwed it to a piece of 18mm ply just a bit bigger than the grinder footprint through to the top of an 18mm ply cupboard top. Should I have fixed it to something thicker? Any thoughts?

John

 

[Monkey Mark]

It shouldn't vibrate too much anyway. Sounds like its out of ballance. Check the grinding wheels are seated correctly.

 

[n0legs]

Make sure the wheels are concentric to the drive spindle.
Best not to use it until you know for sure what's the cause of the vibration and if you can fix it. There's a reason we used to have the Abrasive Wheels Act in industry, I'm sure I'm not the only one to have seen the videos.
Not safe my friend, fix or dispose of.

 

[blackrodd]

Make sure the wheels are concentric to the drive spindle.
Best not to use it until you know for sure what's the cause of the vibration and if you can fix it. There's a reason we used to have the Abrasive Wheels Act in industry, I'm sure I'm not the only one to have seen the videos.
Not safe my friend, fix or dispose of.

As above, Sounds quite dodgy, The wheels need checking to see if the centre reducing spacer is on there, or fitting properly.
Unless a bearing is badly worn, if it's an oldie.
Regards Rodders

 

[John15]

Thanks guys for the suggestions. It's a new one from Axminster, I think discontinued now as I don't see it on their website. The wheels are tight but there appears to be a slight wobble when running. I think I'll give Axi a ring on Monday and see what they suggest.

John

 

[deema]

The wheels on all new grinders need to be trued up to the spindle otherwise you get vibration. You need either a diamond or wheeled stone dressing tool. Axi have them, as do virtually all places that sell grinders. You also use them to remive any glaze of the wheel after a grinding session.

 

[John15]

I've spoken to Axminster today. They say the most likely cause for the vibration is that the wheels need dressing, as deema says above, and they are putting a dressing tool in the post - no mention of cost so I guess it's free. Hopefully it will solve the problem.

John

 

[NickWelford]

Excellent customer service from Axi.

 

[John15]

An update on my grinder problem -

I received the stone dresser from Axminster and duly dressed the stones but it made no difference. So I rang Axi to say the vibration is the same as before. They then arranged for a courier to collect the grinder the next day. I have just had a call from them agreeing that the vibrations are a defect. They apologized for the inconvenience and regretted they are out of stock of this particular model at present so will give me a full refund.

Very good customer relations - an essential part of running a good business. Keep the customer happy.

John

 

[Walney Col]

Still wasted a lot of time thanks to the lack of QC though hasn't it. I wouldn't be singing axminster's praises if they couldn't ensure a simple machine like a bench grinder was put together right first time.

Col.

 

[monkeybiter]

:roll:

 

[John15]

Still wasted a lot of time thanks to the lack of QC though hasn't it. I wouldn't be singing axminster's praises if they couldn't ensure a simple machine like a bench grinder was put together right first time.

Col.

Walney,

How do you expect a distributer such as Axminster to unpack every power tool and machine bought from China, test them for defects then re-box and re-crate them for sale here in The UK? Surely the problem of poor Quality Control lies in the Chinese factory. It will be the inspectors in the factory who should flag-up work that is not in accordance with the spec and the manufacture's own Quality Assurance policy. It's here that the system can break down, not in any small part because the inspector's are frequently employed by the manufacturer and China is well known for incentives to be given for turning a blind eye.

John

 

[Walney Col]

I wouldn't expect axminster to unpack and inspect every tool. but I WOULD expect them to source only equipment which can be proved to have a usable QC program behind it rather than pass on the responsibility of QC to the customer. Even UK law says that responsibility for QC lies with the importer. I suppose I could ask now why you's so eager to let importers keep wasting their customer's time by bringing in hit or miss rubbish when perfectly adequate tools from China cost so little less?

 

[lurker]

I agree with Col

Actually I had exactly the same problem with an ax grinder about 5 years ago.
Difference is I know how to dress and balance grinders and fixed it myself.
I wrote to them moaning about poor QC. But explained I had fixed it.
They did give me a credit note for £25 for my trouble so I am not complaining.

 

[lurker]

Still wasted a lot of time thanks to the lack of QC though hasn't it. I wouldn't be singing axminster's praises if they couldn't ensure a simple machine like a bench grinder was put together right first time.

Col.

Walney,

How do you expect a distributer such as Axminster to unpack every power tool and machine bought from China, test them for defects then re-box and re-crate them for sale here in The UK? Surely the problem of poor Quality Control lies in the Chinese factory. It will be the inspectors in the factory who should flag-up work that is not in accordance with the spec and the manufacture's own Quality Assurance policy. It's here that the system can break down, not in any small part because the inspector's are frequently employed by the manufacturer and China is well known for incentives to be given for turning a blind eye.

John

If the wheel had ruptured at full speed it might have been you with the blind eye

 

[Walney Col]

If the wheel had ruptured at full speed it might have been you with the blind eye

Good point. And of course the legal responsibility for selling a machine in a dangerous condition would be with Axminster.
Col.

 

[n0legs]

I wouldn't expect axminster to unpack and inspect every tool. but I WOULD expect them to source only equipment which can be proved to have a usable QC program behind it rather than pass on the responsibility of QC to the customer. Even UK law says that responsibility for QC lies with the importer. I suppose I could ask now why you's so eager to let importers keep wasting their customer's time by bringing in hit or miss rubbish when perfectly adequate tools from China cost so little less?

Agreed.

I would go further and add that as Axminster have set themselves up as tool suppliers (maybe even specialists), they should be checking what they sell and send out.
It's not like they are Q&B or Homebust, they only sell tools and equipment. Wouldn't take long to plug in and run a tool before dispatch.

 

[John15]

At the factory the machines would be stripped down and crated up on pallets or in boxes by the manufacturer for shipping - is it really expected that the UK retailer should take every machine out of it's wooden crate or box, assemble it then test run it, then disassemble it and put it back in a new crate (the original one is un-useable) before dispatch to the end customer - I don't think so. Some very small items are sold with blister packaging - how can a retailer check that the item is as it should be?
It is a difficult problem but rightly or wrongly it seems that retailers have to rely on good quality control at the factory and if the very occasional item is defective then they apologise and either supply a replacement or do a refund which is exactly what happened between Axminster and myself.

John

 

[CHJ]

I personally think a lot of bulk product movers, not just equipment suppliers, are being guided by an accountant lead marketing model that has a reject quotient built into the acceptable supplier Quality Audit requirement.

The better companies seem to cover this quotient with improved customer support/response that holds the satisfaction/returned customer curve at an acceptable level, for the accountants.

We all know of low cost high street stores that give 3 years guarantee and money back at the drop of a hat if it fails, therefore customer is nearly always ready to give a product a punt, and it seems to work.
As does the sales pitch of companies, one of which I recently had dealings with, that after a query regarding purchase of some extra parts shipped them FOC first class postage from Scandinavia.

If I personally was involved with the supply of most of the powered products aimed at the hobbyist or more discerning customer I would investigate a premium price add on setup option as some suppliers offer, obviously this would not come cheap with assembly and tweaking man-hours but could be held at a discounted price if the accountants offset the mark-up lost with rejected or replaced goods. But common sense tells me that if I shifted enough product to maintain several nationwide show room outlets as well as on-line supply there would be too much work to cope with and too many overheads for not enough gain to fit the accountants retail model.

As far as the OP's problem, for something that looks simple and innocuous but can be so dangerous as a Bench Grinder I think the supplier QA requirements ought to be somewhat more stringent.

 

[Rhossydd]

Wouldn't take long to plug in and run a tool before dispatch.

Ridiculous assertion. Name any company with similar sales to APT that opens boxes, tests and repacks all their goods before dispatch ?

The closest I've ever heard of anything like that was a photographic shop called R G Lewis in Holborn who used to test every lens they sold, but then (in the 1960s & 70s) they were only selling a lens or two a day and charged a very substantial premium... they went bust in 1977.