Inside a cheap knockoff machine, FYI

[BrianMadigan]

I made the mistake of ignoring EVERYBODY'S perfectly good advice advice and got ahold of one of the Chinese knockoff engraving machines. I've been doing hand engraving and I thought I'd speed things up a bit for the large pieces I do as a knife maker. Not so fast!
I set it up as per the instructions, set the air pressure and powered it on. The light goes on, but no fap fap fap from the rotary valve. The gear motor does not spin. So I took the cover off to see what's what. The speed control unit had jumped out of its socket. So I plugged that back in and it worked fine. EXCEPT that it leaks air from every internal fitting excessively. This is annoying, and causes my compressor to cut in every 20 seconds or so. Even when I'm not using it. Yeah it leaks A LOT of air.
This is the inside:


The connector that goes to the air pressure gauge on the front was broken and its spring was distorted. The fitting on the back of the gauge doesn't clear the bracket where the motor is mounted. I fixed this by bending the bracket and re-installing the fitting with a repaired spring. Still leaks..


It DOES function, but the air leaking is annoying, and who knows when one of the fittings is just going to pop. You can see that no expense was spared in the assembly of this thing: sheet metal parts appear to be bent by hand to shape with pliers, use of a couple extra nuts as spacers, soldered connectors look like someone splashed solder on them instead of doing it properly. So, no offense to anyone of Chinese heritage, but this is typical of Chinese knock-off machinery. Yes, it's nearly half the price of a GRS System 3 Deluxe, but it's worth nothing if it doesn't work out of the box.
The anonymous retailer has offered a partial refund, anonymously through Ebay. They said "your local shop can fix, and we will partial refund".
The seller also knows nothing about engraving machines, they just sell 'factory discounts' or Chinese knockoffs basically.
So yeah, don't do what I did against all better judgement.

 

[Crossbolt]

It DOES function, but the air leaking is annoying, and who knows when one of the fittings is just going to pop.

I think one already has - that brass push lock fitting seems to have shot its wad already.

 

[highveldt]

All of us have had times when we were low on disposable income and have purchased items that caused us problems. I think the Lindsay is the best of them all, but others think GRS is best. They both are costly in the short term, but inexpensive in the long term.

Now. To my view you just take what you have there and make it work. I can see that there is plenty of room in the unit to work with and you need to fit up some proper slip on fittings, which will be metric size, or fit up a fitting where you can clamp the hose with typical hose clamps or the like. Don't despair, but make it work. I see on the web where many people in other countries make up their own pneumatic graver systems and they work (how well I do not know), jump in there and make the changes you need, as now you have nothing lose but something to gain.

It is just a matter of time when someone designs and invents a new engraving system, that will likely be some technology using sub-micro super magnets derived magnets from the Swiss and French super atomic particle collider technology and all the pneumatic systems will be laying on the shelves of our shops as we make the change. Todays super batteries that made all the power tool business change in the last 20 years came about due to the battery requirements of NASA 40 years ago; and it filtered down to us as drills, screw drivers, saws and the like. I see the potential new power graver technology as something like a 1 inch long x .5 inch diameter linear compressor that does not compress gas but hammers. That's my story and I am sticking with it (smiles).

Steve

 

[Memorymaker]

Now that's excellent information about the exact reasons why the Chinese knockoffs are not worth it. This thread should be a sticky thread

 

[Eric Olson]

With the GRS system, air is the lubricant for the rotary valve, so it does use air even when not engraving.

 

[speeedy6]

I don't know if it's powerful enough but the motor, if it's variable speed might make a good power hone. Make some lemonade out of that lemon.

 

[sam]

So you've confirmed what many of us have said all along, and I appreciate your post and your review. Nothing would be more frustrating than having a breakdown and not being able to get parts and/or service or tech support from a seller (in China) that knows nothing of the product.

Maybe you can make it work long enough to at least make it pay for itself.

 

[Steve L S]

Highveldt said Now. To my view you just take what you have there and make it work. I can see that there is plenty of room in the unit to work with and you need to fit up some proper slip on fittings, which will be metric size, or fit up a fitting where you can clamp the hose with typical hose clamps or the like. Don't despair, but make it work. I see on the web where many people in other countries make up their own pneumatic graver systems and they work (how well I do not know), jump in there and make the changes you need, as now you have nothing lose but something to gain.

That’s good advise. So often on cheap imported stuff the “bonnet is welded shutâ€￾ – you can’t get at the guts of the thing to maintain of fix anything, but it seems you can at least pull your machine to bits and air leaks are easy to fix. It is probably better than the jalopy that Shaun Hughes of youtube fame has built and look at what he can do on coins with his unit!

Many machine engravers have also taken the risk in buying big powerful Lasers from the Pac Rim because the name brands are simply cost prohibitive but they have set up an internet network to help each other out eg what brands to avoid, what parts to replace and how to do that with upgraded components……as they say - you get what you pay for, and you pay for what you get.

 

[Rstripnieks]

Post looks similar to my engraving vice thread, sad to hear that. I have made my DIY engraving machine from Shaun Hughes video on youtube from screw driver bit holder, 25dollar air compressor for bicycle tyres and electrical devices for speed controling. All together was 65 dollars
It works well but still its uncomfortable , makes annoying noise. And serves me mostly for background removals or deeper carving.

 

[vdrum4250]

thanks for the post, i wanted to buy one to do the same as you have. saved me the cash