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gavztheouch
11-01-2013, 09:54 PM
I have been aware of the fact that there are no thrust bearings or any sort of proper ballscrew mounts on my marchant dice router. Up until now it ain't been much of an issue as I was cutting soft mdf and plastic at slow speed. Last week I had a job to cut some birch and I noticed the accuracy to a hit. All my dimensions were consitently off by 0.4mm or so, regardless of the length of the dimension, this sound like backlash. The couplers are tight so I reckon it is due to the fact that the ballscrew does not have a thrust bearing and the design realise completly on the stepper motor resisting the force on the ballscrew. The stepper won't do this as I was expecting, so I think I will prob need some proper mounts.

Has anyone else got a marchant dice A4 sized router with the same prob?

Here is a pic of the current setup. x,y and z are all indentical.

The x axis ballscrew end arrived bent and the coupler had a lot of runout in the machining, so much so that it wiggles the stepper motor a lot as the axis is moved.

7936

Web Goblin
11-01-2013, 10:11 PM
I had a bad experience trying to deal with Marchant Dice so I dont go near them anymore. Thats really poor build quality not having any support bearings in place. If the shaft is bent and directly affecting the stepper then it will eventually knacker up the stepper motor as well. If you grab the ballscrew by hand can you get any play in it by trying to move towards and away from the stepper?

gavztheouch
11-01-2013, 10:22 PM
Hi Web Goblin,


If you grab the ballscrew by hand can you get any play in it by trying to move towards and away from the stepper?

Yes lots, prob over a mm. :(


If the shaft is bent and directly affecting the stepper then it will eventually knacker up the stepper motor as well.

I know its only a matter of time before it knackers the motor. I actually completely rebuilt the machine last week, had the ball screw in the lathe to check the runout on the ends, straighten it out as best I could. A new coupler would help matters as most of the runout is in the coupler. Actually I thought to myself Ill get some oldham couplers, then I relised I couldn't because the coupler needs to be ridged to work as the motor is holding the screw in place, pretty crap huh.

I know merchant sell multiple routers like this a week I find it stange that they don't support their ballscrews. If they did I think they would have quite a nice product

Web Goblin
11-01-2013, 10:34 PM
Your right, an Oldham coupling definetly wont work. Most couplings will be able to take out some axial play but not any along tha axis. You could disconnect the stepper and see if there is any play in the shaft to see how its holding up. Looking at the photo its hard to see what you will be able to modify to add a bearing block to support the shaft. what you might have to do is make a bearing block to fit on the motor side of the vertical support and then an extension shaft to be able to refit the motor and coupling. Saying that you could save a bit of space by making the through hole for the ballscrew larger and recess the bearing block in it.

gavztheouch
11-01-2013, 11:21 PM
7937

If I could fit a block in the inside like this I could retain the same mounting block for the motor. I would be a little hesitant about milling into the aluminium extrusion as I don't have a mill.

Web Goblin
11-01-2013, 11:26 PM
Yes that should do the trick. Didnt know if you could get it on the inside but if you have enough space that would do. Cant you mill it on your machine?

AdCNC
12-01-2013, 12:33 AM
Its shocking to see that companies selling crap like this can get away with it, i my opinion thats not even fit for its purpose. Shocking....

i2i
12-01-2013, 12:58 AM
is there anything on the other end of the ballscrew

gavztheouch
12-01-2013, 01:15 AM
The other end is floating inside a bearing which is pressed into the gantry extrusion. I thought about welding a new end onto the side that is not driven, then maching this side to take the bearing block. That way the thrust bearing will be on the "wrong" side of the screw but it would mean less mods to the router as it stands. What do you think?

i2i
12-01-2013, 01:38 AM
a cost effective route to thrust bearings is to use a deep groove roller bearing on the opposite end of the ballscrew to the motor, which is fixed on the ballscrew and anchored to the frame. This is quite common on lower end machines and often gets mistaken for just an end support bearing. It's not ideal but gives a reasonable amount of thrust protection.

gavztheouch
12-01-2013, 02:03 AM
How would you attach the bearing to the screw, locktite retainer?

i2i
12-01-2013, 02:52 AM
from what i've seen the end of the ballscrew is threaded either internally or externally and a cap screw and retaining plate is used to hold the bearing onto a journal, or simply held on with a nut on an external thread.
Obviously this depends on the quality of the bearing for backlash removal, and is not much good for heavy loads as the bearing is designed for radial loads not axial loads.
If you want the correct method then you need two opposing angular contact bearings in a housing.

cropwell
12-01-2013, 10:19 AM
How old is this Marchant Dice machine ?

Web Goblin
12-01-2013, 10:28 AM
Can you post some photos of the opposite end of the screw so we can see how its mounted?

gavztheouch
12-01-2013, 01:14 PM
79387939

Here are some pics of the end mount

I bought the router about a year ago

Jonathan
12-01-2013, 01:41 PM
I wonder if this is where strikecnc got the idea of not using proper bearings on the ballscrews.

Anyway, I think the easiest way to solve this is to buy a pair of FK/FF bearing blocks since so long as the extrusion is long enough you can drill a hole in either side and put the new bearing mounts in. That's assuming the ballscrew end machining is standard, what does it look like?

Also, I'd solder those motor connections as if they work loose whilst the machine is running the stepper driver could be damaged.

cropwell
12-01-2013, 01:47 PM
It looks as though you have some end float which could be shimmed out.

Web Goblin
12-01-2013, 01:54 PM
Thats even worse than I thought it would be. The only thing keeping that bearing in place is the ballscrew and if its whipping about it will start to pull the bearing out as well. The first photo isnt very clear but it doesnt look like there is any kind of nut or circlip holding the ballscrew on the outside of the bearing.
I would either buy or make two bearing mounts and get them fitted but you might have to get some lathe work done on the ballscrew as I cant see it already having threads for a securing nut.
Another option would be to use the bearings blocks on the insides of the gantry and have the shaft lathed to fit between the two blocks, some spacers might be required as well. The two blocks on the inside would remove any sideways play from the ballscrew.

JAZZCNC
12-01-2013, 02:45 PM
First choice would be Throw the thing in the scrap bin where it belongs and start again.!!. . . OR. . . Failing that A simple fix would be use a thrust bearings at coupler side of profile, presuming the other has deep grove bearing, and thread the shaft and put locking nut on.

Better way would be machine the profile to accept angular contact bearings then thread the shaft and lock nut or use Bearing block machine screw to fit.!

First choice would be best solution.!!. . . . . . If you wan't to know all the hassle coming your way with if you continue with this pile of shite then just contact Micheal (M.Marino) has he's been there and pay'd the price. Honestly not worth the price of the thrust bearings in my experience.!!

blackburn mark
12-01-2013, 03:23 PM
a double row angular contact may be a simple compact way forward if you can squeeze one in somewhere

3200 5200 ZZ Series Metal Shielded Double Row Angular Contact Bearings - Choose | eBay (http://www.ebay.co.uk/itm/3200-5200-ZZ-Series-Metal-Shielded-Double-Row-Angular-Contact-Bearings-Choose-/320847188541?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3 D1%26asc%3D14%26meid%3D4823921484369492029%26pid%3 D100015%26prg%3D1006%26rk%3D1%26sd%3D320847188541% 26)

JAZZCNC
12-01-2013, 03:34 PM
a double row angular contact may be a simple compact way forward if you can squeeze one in somewhere

3200 5200 ZZ Series Metal Shielded Double Row Angular Contact Bearings - Choose | eBay (http://www.ebay.co.uk/itm/3200-5200-ZZ-Series-Metal-Shielded-Double-Row-Angular-Contact-Bearings-Choose-/320847188541?_trksid=p5197.m1992&_trkparms=aid%3D111000%26algo%3DREC.CURRENT%26ao%3 D1%26asc%3D14%26meid%3D4823921484369492029%26pid%3 D100015%26prg%3D1006%26rk%3D1%26sd%3D320847188541% 26)

These would still need a retaining ring or plate to stop the outer bearing floating.!!

gavztheouch
12-01-2013, 03:59 PM
7940

This is what I think I would need machined to take the bearing blocks at the drive side. The top pic shows whats there and the bottom shows what I think I need.

As there is not enough material, I would need to chop the current machined end off and weld a new one in to give me the material I need for the new design.

This is how I have machined my ballscrews before as my lathe aint up to the job of machining the hardend casing off. It makes the maching a lot easier anyway and as the welded on blank is oversized when it is turned down in the lathe it brings itself concentric with the screw.
http://i59.photobucket.com/albums/g282/Gavztheouch/P1070450.jpg


Something like this for the bearing block?

http://www.zappautomation.co.uk/en/fk-type-c7/217-fk08-c7.html

Its a little smaller than the recommended block but I doubt it will matter too much for this router as I am only looking get something in there that will work relative to the limits of the rest of the machine.

blackburn mark
12-01-2013, 04:31 PM
These would still need a retaining ring or plate to stop the outer bearing floating.!!

i wasnt thinking old knicker elastic and tape lol

JAZZCNC
12-01-2013, 04:59 PM
This is how I have machined my ballscrews before as my lathe aint up to the job of machining the hardend casing off.

That looks like a Myford lathe and with the correct cutting tool will handle machining ballscrews, my little boxford does. But with this job then it wouldn't hurt to anneal the end up to remove hardening.

From the pics of motor with screw then there is a bit screw left with enough room for a nut so just thread the whole lot then grind flat spot for coupler screw, you may have to machine a new coupler or a sleeve.? . . . Sure it could be done easier than welding bits onto screw.!!

Web Goblin
12-01-2013, 08:21 PM
That bearing block from zapp would do nicely. You could fit one either end of the screw on the inside faces. All you would need to do is machine down the shaft to fit the bearing and they would still be long enough to fit back on.

m.marino
13-01-2013, 09:49 AM
I had one (sold it) with the trapezoid screws on it. From the way that They make their set up you should have just enough to put that FK block in on the inside and if you got an FF block as well for the other end you should be able to get rid of the play with the grub screw and a bevel washer or two (someone correct my spelling of those please). That or you could go with an angular contact bearing on the free with said washer and grub screw. Good luck on getting it to cut better, If that is the model with the unsupported round rails on Y you might want add a plate across that back to improve rigidity.

He has changed design a little bit over the last 4 years, depending on which year model depends on what needs to be done to make it work at anywhere near the capacity that they state it can. Let's just say I was not overly impressed with my machine and the work I had to do on it to get any where near accurate cutting from it, compared to what I was told it was capable of. Hence the reason for the machine I currently use.

Michael

gavztheouch
13-01-2013, 01:44 PM
Hi Michael, my machine is around a year old. It has hiwin profile rails on the long axis and unsupported rounds on the other two. Ballscrews on all three axis.

In soft plastic and foam it is really accurate and I can get rapids of 3000mm/min pretty easily and smoothly.

Its really only with harder materials it begins to struggle, luckly I have had quite a lot of work given to me for prototyping in soft plastic which has made the machine pay its way.

I don't know if it is worth modding the machine to be able to process hardwood, I could keep it solely for softplastic and modelling foam. But if I could do it with as little risk to ruining the orginal machine as possible it may be worth the risk and effort.

I think the easiest way to achive this would be a ballscrew support/fixing block from zapp, and to mount this on the side that is not driven. This would mean buying to blocks at about £35 each plus modding the ballscrews. Total cost about £100 and two days work.

Out of interest which machine are you running now Michael?

martin54
13-01-2013, 02:18 PM
Michael doesn't use a branded machine, you can read the build log for it here.
http://www.mycncuk.com/forums/router-build-logs/3661-1st-build-second-machine.html

gavztheouch
15-01-2013, 10:35 PM
http://i59.photobucket.com/albums/g282/Gavztheouch/P1070715_zpscca74a2f.jpg
http://i59.photobucket.com/albums/g282/Gavztheouch/P1070714_zps18edd9f3.jpg
http://i59.photobucket.com/albums/g282/Gavztheouch/P1070713_zpsd528f462.jpg

Digging a little deeper I noticed the ballnut for the x-axis is simply pressed into the extrusion, it looks like friction is the only thing holding it in there.

JAZZCNC
15-01-2013, 10:54 PM
Digging a little deeper I noticed the ballnut for the x-axis is simply pressed into the extrusion, it looks like friction is the only thing holding it in there.

Surprise surprise.!! . . . I've been chastised many times or warned about possible Legal action for calling these machines and always replied " If it ever got to court then my Undefeat-able defence would be the machine it's self " . No court or Engineers report would disagree these machines are Bad and unfit for purpose.!! . . . . . .Totally disgusting the guy should be ashamed.




Just HOPE people looking to buy see this thread and take note.!!

gavztheouch
15-01-2013, 10:59 PM
Just HOPE people looking to buy see this thread and... not buy mine :frown: (When I flog it to buy something else.)

Actually do you think I have any rights to make them take the machine back and give me a refund.

Looking back through my emails the invoice is dated 6th of Jan but I didn't recieve the machine until Feb. So I have had the machine for less than a year.

m.marino
15-01-2013, 11:29 PM
I could put you in contact with a few advocates but you would have to move quickly due to the time issue. Though the fit for purpose (FFP) issue might be different up here in Scotland and you might wish to look into it. personally I sold mine as is and documented the limitations to the buyer (that way I am being honest to the next guy down the line). There is no way, given an machinist and industrial engineer's opinion in court that they would win on a FFP case. Not on their smaller hobby units, that I was told would have no problem handling acrylic and hard woods.

Michaael

JAZZCNC
15-01-2013, 11:32 PM
Actually do you think I have any rights to make them take the machine back and give me a refund.

Looking back through my emails the invoice is dated 6th of Jan but I didn't recieve the machine until Feb. So I have had the machine for less than a year.

Not really after nearly a year.!! . . . . Thou you could contact him and say how upset you are about the disgusting quality of build and see what he says or his prepared to do help ease the pain.?

Shinobiwan
16-01-2013, 12:04 AM
These make Strikes attempt look passable!

Marchant Dice? More like Rip Off Marchant. C$£ts!

If you don't mind me asking how much did they charge for that? I'm guessing about £2000?

gavztheouch
16-01-2013, 12:32 AM
Close to £2000 yeah.

I think the complete system was £4000 for the extra £2000 you get a shite pc with mach and three stepper drivers.

JAZZCNC
16-01-2013, 12:41 AM
Close to £2000 yeah.

How F@~$ing much. . . .and you didn't even get drives.? . . . .What did you get for nearly 2K.

Working on those prices the machine I made for Micheal would be £30,000. . . :hysterical:

gavztheouch
16-01-2013, 12:45 AM
Everything in the pictures including the motors. No electronics.

m_c
16-01-2013, 12:48 AM
I'mnot wanting to defend Marchant's machines, but press fit works fine if done right. There are far more critical machines relying solely on pressfit to keep things together.

As for the lack of thrust bearings, I've got a lathe that would of cost far more than a few thousand in todays money that relies on the stepper motor bearings to hold ballscrews in place. It's not ideal, and most likely will have an effect on longitivity, but it works.

I am wanting to upgrade my lathe, but it's still currently rattling out lots of parts bang on size without any issues.

JAZZCNC
16-01-2013, 12:57 AM
I'mnot wanting to defend Marchant's machines, but press fit works fine if done right. There are far more critical machines relying solely on pressfit to keep things together.

Think you'll be hard pressed to any commercial or even serious Hobby CNC machine that press fit Ballnuts or run ballscrews without some form of end fixing.?? . . . It's Bad practice pure and simple and proper manufacturer wouldn't do it.!

John S
16-01-2013, 01:01 AM
What size machine is this we are talking about ?

Press fit is fine provided it's pressed into something substantial, pressing a bearing into a length of licorice extrusion doesn't cut it with me.

Also stepper motors have one bearing pre loaded with a wavy washer to allow for expansion, any design that relies on this setup of deep grooved bearings and flexible thrust again isn't good design.

I can understand cutting corners to save money, many make that mistake but at these prices quoted they are not cutting corners to save money they are fleecing customers who believe all the bullshģt

gavztheouch
16-01-2013, 01:12 AM
The press fit as bad as it may look does not concern me as much as the steppers holding ballscrew in place. The reason being is I can measure the shaft of the motor moving along the motors axis as the load on the ballscrew changes. Inside the motor is a spring washer, if you pickup a stepper and try pulling and pushing the shaft you will see it takes very little force to move it. Maybe your lathe has different types of steppers with thrust bearings built in, or maybe its designed to work within the range of the spring washer inside?

gavztheouch
16-01-2013, 01:16 AM
john this machine has a working area of around 300mm by 500mm

JAZZCNC
16-01-2013, 01:31 AM
The press fit as bad as it may look does not concern me as much as the steppers holding ballscrew in place.

But it should do because it's only a matter of time before that's floating around more than screw and stepper do.!!

Think I'd be putting at least a Grub screw of 2 thru the profile has a minimum precaution.?

m_c
16-01-2013, 01:31 AM
Think you'll be hard pressed to any commercial or even serious Hobby CNC machine that press fit Ballnuts or run ballscrews without some form of end fixing.?? . . . It's Bad practice pure and simple and proper manufacturer wouldn't do it.!


I wasn't actually meaning specifically CNC machines! I was thinking about any machinary in general.
The fact is though, in this particular application, I doubt the steppers/ballscrews will generate enough force to move the ballnuts in the extrusion. It's quite smart, in that it does the job while reducing parts count and the amount of machining needed. Maybe not the ideal way to do it, but perfectly functionable.
Large CNC machine builders won't do it because of serviceability. Pressing something into something easily handled is a bit different from something pressfitted into a lump of iron weighing several hundred kg. There's also the manufacturing issue. A few tapped holes, with a locating boss is easier than a single tight tolerance pressfit.

I'm not defending MD though, especially given the prices. I'm just saying the methods used are maybe not ideal, but they're still perfectly functional.

JAZZCNC
16-01-2013, 01:38 AM
It's quite smart, in that it does the job while reducing parts count and the amount of machining needed. Maybe not the ideal way to do it, but perfectly functionable.


Erm.!!. . . . I'd be more inclined to call it lazy arse bodging fueled by greed.!!

John S
16-01-2013, 01:48 AM
An anteater is also functional but I wouldn't want to take one out on a pub crawl and bed it afterwards.

Mind you if they are serving Old Rosie scrumpy it might stand a good chance.

martin54
16-01-2013, 02:30 AM
An anteater is also functional but I wouldn't want to take one out on a pub crawl and bed it afterwards.

Mind you if they are serving Old Rosie scrumpy it might stand a good chance.


Yes but it you met an anteater at the end of your pub crawl you might take the sexy young thing home to bed with you, then in the morning you have to gnaw your arm off to get away without waking it up !!!

Web Goblin
16-01-2013, 07:14 AM
Looking at this it seems the machine isnt getting any better. Press fits are normally ok with certain materials but not pressing steel into aluminium especially when its not actually been machined to fit it in the first place and its supposed to be a permanent fit. The more I read this the more I'm glad I managed to send all my stuff back to them and get a refund although it was a struggle to get it.
I would go with Jazz recommendation and get a grub screw through the side of the alu to hold the nut in place. Remember you just want to dimple the casing of the nut for the grub screw to locate into and get some thread locker on it.

martin54
16-01-2013, 12:07 PM
Can't see how a grub screw would help much in this case, no where to put it really, with the centre of the profile rail machined away the fit is only relying on 4 very small points of contact so you would need at least a grub screw either side but there is a big gap between the profile rail & the ballnut which would probably make the grubscrew ineffective.

marchantdice
16-01-2013, 01:34 PM
Our designs have been through many years of development as our business has grown, we have automated many of our processes using our machines, to produce components for sale via eBay and worldofcnc. Any issue we would evaluate and redesign.

As the majority of our customers have business interests and therefore purchase a machine that is task related, we can adapt one of our many designs accordingly.

Press fit ballnut?
The ballnuts are not press fit….we use RSW ballnuts with an external V thread, the centre aluminium profile is bored and threaded to accept the RSW ballnut…
This range of machines are supplied to the world's leading probing manufacturers, in tests we achieve an accuracy of less than 0.010mm/300mm of the whole machine.

Later this year, all our Ballscrew driven machines will be fitted with thrust bearings this will align our product with our Class 5 preload Ballscrew driven machines and coincide with our 5 axis CNC being launched.

Finally
The floating end of a Ballscrew….
What happens if the Ballscrew spindle became warm? The spindle would need to expand along its length, hence the term floating.

If anyone would like to discuss in more detail please email admin@marchantdice.com or call us 01805 628222 (phone line currently down however will be working again in the next day or so)

Many thanks
Kevin Marchant

gavztheouch
16-01-2013, 02:37 PM
This range of machines are supplied to the world's leading probing manufacturers, in tests we achieve an accuracy of less than 0.010mm/300mm of the whole machine.

In this situation you can see how thrust bearings may be of less importance, but these kits are being sold as cnc routers with the ability to cut material. Try yanking on the stepper shaft and feel the washer inside, unless I have misunderstood again this is the only part resisting axial motion.

gavztheouch
16-01-2013, 02:43 PM
http://i59.photobucket.com/albums/g282/Gavztheouch/P1070721_zps59919348.jpg
7962
This is a quick mock up to mount my thrust bearings. This will fix in place the normally floating end, this means the spring in the motor will soak up the expansion of the screw and the motor side will effectively become the floating end, if it need more I can use a oldham coupler.

Il need another 4 holes that will be tapped to fix the bearing to the mount which will be made of aluminium.

Shinobiwan
16-01-2013, 05:03 PM
Our designs have been through many years of development as our business has grown, we have automated many of our processes using our machines, to produce components for sale via eBay and worldofcnc. Any issue we would evaluate and redesign.

As the majority of our customers have business interests and therefore purchase a machine that is task related, we can adapt one of our many designs accordingly.

Press fit ballnut?
The ballnuts are not press fit….we use RSW ballnuts with an external V thread, the centre aluminium profile is bored and threaded to accept the RSW ballnut…
This range of machines are supplied to the world's leading probing manufacturers, in tests we achieve an accuracy of less than 0.010mm/300mm of the whole machine.

Later this year, all our Ballscrew driven machines will be fitted with thrust bearings this will align our product with our Class 5 preload Ballscrew driven machines and coincide with our 5 axis CNC being launched.

Finally
The floating end of a Ballscrew….
What happens if the Ballscrew spindle became warm? The spindle would need to expand along its length, hence the term floating.

If anyone would like to discuss in more detail please email admin@marchantdice.com or call us 01805 628222 (phone line currently down however will be working again in the next day or so)

Many thanks
Kevin Marchant

I'm sorry Kevin but you will win no supporters on here for your method of construction.

I bought a copy cat of one your machines that was actually better in some cases than yours but still inadequate. In this case at least it correctly captured the ballnut but still had similar issues with the ballscrew mounting that you have engineered into your designs.

Its sloppy, cheap and has serious question marks for the long term accuracy of the machine. You're basically knocking these out as simply as humanly possible to maximise profit. It wouldn't be so bad if you were charging a suitable amount but 4 series extrusions with the most basic and barebones mechanical make up possible? Not acceptable in my opinion.

You talk about selling to businesses? Your going to cost them money in the long run because they'll have to fix or replace what you should have done right to start with.

Please go back, redesign and come with something fit for purpose and stop inflating the capabilities of your machines. They're very very lightweight machines capable of only light cuts in soft materials. And your accuracy figures mean little. Is that the accuracy of a part, if so what material? Or is it more likely the accuracy of the machine with no load ie. cutting air?

magicniner
03-09-2016, 03:22 PM
Just reading through older stuff and saw this, I always thought their stuff looked particularly shonky for the price on eBay but it looks like they manage under-engineering on a scale that would put professional bodgers everywhere to shame!
Boring and threading the "Liquorice Extrusions" was the high point of the BS excuse for me!
Anyone seen any of their more recent contraptions?

cropwell
03-09-2016, 08:21 PM
I had the problem of the floating acme screw and I put in a small thrust bearing from ARC Euro held against the motor mount extrusion by a collar with a grub screw to remove the end float on the screw. I did similar on the X axis, but the Z axis was a slightly different bodge as I needed to prevent it pushing upwards, so I put in a couple of thrust bearings to space it out (1 bearing and washers would have done !) and used the coupler to act as the retaining collar.
19137

The machine is now (just) adequate for hobby use.

But I have to give a big thank you to Marchant Dice for opening my eyes to CNC. I now have the great desire to make a decent machine.
This quote from MD amused me 'in tests we achieve an accuracy of less than 0.010mm/300mm of the whole machine' I would have expected better than rather than less than, but Hey Ho maybe ?
Cheers,

Rob

BTW Nick, I have not seen any of their recent excrences - I believe their machines should be labelled 'For amusement only', they certainly make me smile :shame:
AND I like your use of the word 'contraption' - very apposite.

magicniner
03-09-2016, 11:04 PM
I believe their machines should be labelled 'For amusement only'

And perhaps "A Learning and Growing Experience"? :D

John S
05-09-2016, 03:23 PM
I believe their machines should be labelled 'For amusement only', they certainly make me smile :shame:
AND I like your use of the word 'contraption' - very apposite.

Now that was funny