MDF Sign
 

Hi All

Was buying some food for the beast and came across this sign at a "big box" store.

Attachment 15016

My Mechmate is of course not scared of MDF dust as it never gets a chance to escape using my very high tech vacuum as you go technique :).

Attachment 15014

This is the off the machine finish at 30mm/second at 3.1mm DOC.
The bit used was the 3mm carbide burr mentioned in my previous posts.
Nice, no finishing required.
By way of an explanation these are prototyped parts to be sent off to be laser cut in metal or alloy later on.

Attachment 15015

Regards
Ross

Hexacopter
 

Hi All

Forgot that I never posted the hexacopter that I designed and prototyped for my flying friend.

Attachment 15017

Attachment 15018

Enjoy
Ross

Very Cool.

I will definitely look into the burrs.

Nicely done as always.

Hi Ross,

I remember you have used PU airlines for your coolant ?
Did you use PU lines and automotive coolant ?
Somebody warned me that these are incompatible and the chemicals inside the coolant will eat the PU lines. Reason I am asking is I already have the PU lines installed on my machine and was planning on using the automative coolant and hope to be firing it up soon but I don't want the MM to become incontinent and piss all over itself on it's first start up and clog up the spindle with a layer of PU.

Backup plan is using distilled water for now while I look for better chemical resistant air lines, but since you have been runiing for some time now you might be able to take away my worries.

Hi Fox

The lines that were used on my machine were just big box food grade clear lines.
The chemical incompatibility issues appear to be overstated esp for our application.
I have had a very high concentration of ethylene glycol running through the same lines for years now.
What does happen though is the the transparency of the lines is compromised over time.

These days pneumatic tube that fits all the push fit type fittings both of which are available cheaply on Ebay might be the way to go.
The reason to use this is primarily so that you can replace the input and output ports on the water cooled spindle with a push fit fitting.
The push fits have a bigger internal diameter than the hose compression type fittings supplied.
If you want to make the internal gallery on the threaded push fit larger you also can drill out the fitting a little to even further reduce restriction to the water flow.

The lines are easy to thread through the cable chains so either way a swap out later on is a quick job.
A pump that has strong flow at a 1.5 - 2m head with a bit of restriction is probably the most important part of the cooling solution.

Regards
Ross

Hi Ross,

I got all that sorted and mpounted on the machine already, but thanks for the tips anyway, very helpful as always !

The internal holes are all small in these chinese spindle, I have seen that elsewhere when somebody took it apart, so not much help in enlarging the connectors that way.
Must be a reason why the chinese built it like that, although the reason probably is that it's good enough, and the CHEAPEST :D. Everybody who buys it wonders about them holes being so tiny.

I was just wondering about the compatibility of PU ãirlines with the chemicals. Guess I will run a test for a while.

Hey Ross,

Good to see you back at it, great work on the little quad :D love your work !!

Cheers
Tony.

Quick PU research
 

It appears PU and PUR lines are good for almost everthing per this web site: http://www.newageindustries.com/polyurethane_hose.asp. There are two types of PU tubing, an ester based and an ether based. Ether based PU evidently works better (doesn't change properties as quickly) in mainly water environments and is more fungus resistant than its ester baed cousin.

No, I don't even play a chemist or chem engineer on TV. I just know it does make a difference depending on the application.

Fox,

PU tubing will degrade, swell and rupture with various chemicals. Even oil in air lines has its toll on it. In this pdf is a guideline list on what PU is affected by. http://www.camozzi-usa.com/sites/def...ane-tubing.pdf. I found various tables before. I do work with PU a lot and chemicals will degrade it rapidly. The charts are for conveying a pure form of the substance. I hope this helps.

Ordinary clear tubing, with G12 antifreeze (for aluminium) diluted 1/2 works for me and couple of friends for last 4 years in chinese spindles.

So the documents say No, and the real life experience says Yes... what to make of it ?? :o

Danilo, diluted with tap water ? Or deionized water ? your lines are porbably PVC then right ?

Tap water has too many impurities in it. I would just mix it with distilled and you will be fine.

Distilled water

Just because water or oil 'breaks it down', doesn't mean we should not use it. Just remember it MAY be a disposable solution when using it. ... No harm, no foul.

Water will not but glycol may. Food Service PU will be more resistant. But I was not saying not to use it. I use PU on mine, however, caution should be taken when using anything without evaluating all the factors involved. For instance, if you have a dog that likes to chew or is attracted to antifreeze. This could prove to be a nightmare. So it is up to the individual to make their own choice.

I am running antifreeze and no dog :D
Will check it from time to time.

I am running antifreeze in Pneumatic PU pipe w/o dog but lots of rats, gave up on checking routine checking long time ago... :p

Maybe you need the dog :D

Hi Ross

Hope your beast is doing well. A question from the past.... when you elongated the holes in your X rails, how did you do that? I will need to do the same with mine to give me more adjustment.....

Cheers

It has been quite some time and at this point I am having trouble recalling :confused:
Ross

I understand, at my age I have the same problem :)

Elongated holes
 

Pretty sure we used a die grinder bit, $25 to $30 for a air die grinder Supercheap or Bunnings and around $20 for a bit.

Cool, thanks for that. Never even thought of a die grinder. I have 2 of them, just need some bits

Ross,

On post 1038, you have a new bit that you used to cut MDF. Would you please provide some more details on the bit. Could you PM me with the details.

Thank you.

Hi Nils

Done.

Ummm.. is it that secret? :) Just watched the video and would be interested myself....

The bit looks similar to what they use on graphite and composites.

AHa, I think you're right Pete:

http://www.toolstoday.com/p-6194-sol...keywords=46133

And here http://www.onsrud.com/xdoc/composite-cutting-tools

Tools
 

Depending on what you are cutting, but I was talking to a guy that cut a LOT of MDF. He found diamond encrusted tools lasted longer than carbide. They lasted about twice as long. I haven't tried that, just thought I would pass along the suggestion.

I have a friend that works in fiberglass industry and that is what they use. Rotary diamond coated cutters. Inexpensive based on life of the tool and the speeds you can run are faster than than most Mechmates can run (they cut off the extrusions at 1500 IPM) but the downside is you really need excellent dust management. I would not see how MDF would be much different but like I said if you can manage the dust appropriately it would be the way to go.

Ross, what are the current accel and velocity settings on your machine ?

I am interested in what Ross used because I have alwayschad problems cutting 3mm MDF. I have mainly used 3mm/1/8th down and upcut bits and the finishvhas been nothing like what is shown in the video.

I use a 2.4mm straight cut, you get pretty good finish with a quick sand any swarf is gone. I cut shapes for a craft person do up to 300 at a time, while a sheet is cutting I'm cleaning the previous ones.

Hi All

I see you have figured it all out in my absence.
As Pete says they are dusty but the finish is one a lazy man can quickly grow to love.
Also correct on the diamond coated bits.
I know of a fiberglass fin guy and he uses a lot of those as the glass is very prone to blunting the tools.

In G10 (or an epoxy and fiberglass panel in everyday terms) the tool life of the burr type cutters far exceeds that of a good quality two flute carbide bit.

Have a good time playing everyone.

PS still making a surfboard or two for myself every now and then.
Some things never change !

Regards
Ross

Composite Surfboard Skins
 

Hi all

The Mechmate is still the best tool in the shed.
This time the machine made a good layup table and then cut some fiberglass skins out for me.

3 x 4Oz layers of fiberglass cloth are layed up on a waxed melamine sheet.
Dry
Attachment 15404
Wet Out
Attachment 15405

Once dry the skin is peeled off the waxed sheet and mounted for machining.

Machined Skin
Attachment 15406
Attachment 15407

The finished skins are then vacuum bagged onto a shaped EPS foam surfboard blank.
I'm sure fellow Mechmate owner Red_boards knows all about this :).

Regards
Ross

I always like seeing different ways things are made. Thanks for sharing.

Cool !!