I would like to continue this conversation at the frequency of 2007-2008, anyone interested?
The cheapest stable structure I can think of off the top of my head would be 12" cement blocks with machined aluminum plates bolted in between them (and maybe steel ones on the ends).
I would like to continue this conversation at the frequency of 2007-2008, anyone interested?
I was hired by a newborn ONG here in South Italy to build an affordable CNC milling machine able to cut tactile maps. The budget is extremely tight. I am considering building the frame in polymer concrete (to avoid casting iron and welding/annealing steel) and use DWH resin (from Diamant) for squaring (to avoid milling, surface grinding and/or shimming).
Looking around on youtube videos, forum threads (including this one), thesis and scientific pubblications (most of all were already cited here), blog posts (ike CNC cookbok - which remainds here)... I'm just getting more and more confused.
an affordable CNC milling machine able to cut tactile maps. The budget is extremely tight.
Step 1: realise that you did not make that budget decision, so you do not carry the responsibility for any problems coming from that budget decision. If the company wants to play real cheap, they get real cheap. You do the best you can and don't lose any sleep.
Cheers
Roger
Part size, material, needed precision are all factors in recommendations. On the cheap(er) I'd point you to kit or plan wood cnc routers. You don't have to design and rework design when something doesn't fit.
I'd also suggest getting with local metal working clubs, maybe someone would be interested in a team project. Maybe they weld, you pick up scrap steel and 2 units get build.
One epoxy/granite project was started but the guy found he could get a granite slab fairly cheap and drilled and epoxied in inserts.
Which your location made me think of. Maybe hunt for stone drops, sink cutouts, defective tombstones.
defective tombstones.
The Mafia hit failed. The guy is not yet dead.
Cheers
Roger
Every kit and/or built machine I looked for just sucks... I know that I'm used on HAAS, Hermle and Matsuura machines... but paying 10,000$ for a machine which vibrates like hell doing a dry routine (with even the motor disabled)...
"Metal working clubs" ? Nothing. Only an old man who can to do the face milling for cheap on his large, old cast-iron milling machine in his huge all-manual shop.
I also considered using granite slabs, like this guy did:
But the costs went in the sky (we need a minimum working area of 600x400) trying to use scraped granite plates.
Has anyone tried using those hand held pneumatic or electric concrete vibrators?
es, I have tried about anything you can think of with polymer concrete. It is important that the vibration compacts the material and does not induce air. You can manually compact the material using a tamper (a 2X4 and hammer).
Tried the concrete vibrators like the "rod style".. dont work, EG is to sticky. Best sucess has been with one of those grain bin vibrators that is bolted to the outside.
Very simply 2 bearings, shaft, pulley, adjustable offset weight
That could work, my experience is that you wanna shake the aggregate to a point where it is basicly fluid tho. While shaking you should be able to press your hand or a roundbar or something down into the bottom of the container with no effort.. And i mixed in the epoxy during this state of shaking, make it dispearse and really cover all the aggregate properly.
Looks like a job for a mallet and a wide tamping bar to me. It's solid stuff.
Cheers
Roger
I bolted one of those grain silo vibrators to the mould, and used a VFD to tune the frequency till I find one to help it sag. I would not expect anything less to be effective.
Mark
Regards,
Mark
The inside of those silo vibrators is a motor and 2 offset weights. That's what gave me the idea for using a grinder with 2 pulley's to which you could bolt panels. But I didn't think the grinder's bearings would be sufficient. Started me thinking about the axle and offset weights when I found some uTubes of concrete block forming and a couple showed the same setup.
Yep. I used one of them, with a VFD to look for resonant frequencies.
Regards,
Mark
Variable frequency drive otherwise known as an inverter. The one I used was 1 phade 240v in and three phase 240V out.
Regards,
Mark
Hi Mark
Do you still have the excel sheet from Thomas?
I can't find it unfortunately
Thank you
@all: thank you for all your efforts. I'm going to poor the first batch of test in May I hope. let's see what happen
I really struggle to find zeeosphere, I think I will use crushed sand of abarasive glass balls instead...