david hogg
Forum Replies Created
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Hi Martin speeds and feeds Are not the most important thing they are dependent on the material in general they will be somewhere in the region of 25mm per second up to 80mm per second you just need to give the cutter the chance to clear the chips away form the work piece cutting fluid makes a big difference to speeds you can run at also reducing vibration in the work piece is very important as well as cutting flute length all have factors I how fast you can cut alu.
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Andy get a simply bit of electric cable strip one end and spread the cooper wire out and tape it to the end of the vacuum hose where you are sucking up the the waste then ground the other end to the floor this will transport the static electric away from the machine also check the vacuum pressure sounds like its not strong enough to suck up the waste static alone should not stop the vacuum from drawing it away from the work piece
Hope his helps
Dave -
Hi dave first thing you need is some good tooling and a mist coolant system there is very few grades of aluminium which you can dry cut so a mist coolant system is essential you can buy them online for about £50 this will be the best spent money you will apply to any router take my word on this 16 years Cnc routing does not lie , next is your tooling and workpiece hold down I normally use 2 different tools both 6mm dia
One for a rough cut and a different one for he final cut I can get a mirror finish on my aluminium parts so believe me this works , I use a 6mm singe flute upward spiral cutter from itc with as much clearance in the tool this helps stop heat build up and prevents the aluminium moulding into the cutter surface but you need the mist coolant to help it once you hint the sweet spot on the cutter you should hear it change tone thats how i know if its machining well thats the must important part speed feeds and spindle rpm are not that critical run the spindle as hard as it goes 18000 or24000 rpm
What ever she does do your rough pass but do not cut right though and leave a .5mm to trim of on the final cut . Do your rough cut then change tool to a new one and do final cut with it feed rate about 40-50mm per second is what I normally run at but this normally depends on the aluminium . If this is a bit confusing give m a call on Monday and I an go though it better over the phone I cut aluminium all the time been machining it for 20 years so know a bit about it
Hope this helps dave
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Hi Roy short answer is yes you can make a 3d model of the mould and allow clearance then simply 3d carve the mould , you can also use tapered cutters to cut clearance like what Jason has linked , if you uploaded a picture of the model you are trying to make I could advise you on the best technique to make it , I have made loads of moulds over the years in MDF and I works very well especially if you use high density Mdf or HDF
Hope this helps send more info and I should be able to help you more
Cheers dave -
Hi Warren what you could do is powder coat the overall panel which would be precut to the outside profile then machine out the text on the router then colour fill it with the lighter blue quite straight forward we could do this for you if you still need it
Dave -
Hi dave as Ian said sign block is the material you looked at but it’s is expensive cuts great mainly used for 3d carving as it hold detail very well I have machined lots of it never for letters just to dear for that application stick to PVC as everyone else does but even that is getting quite dear now Mdf is cheap and they have a new type of Mdf which is waterproof it’s the best material I have seen I along time totally waterproof I placed it into a bucket if water for 4 months and it never sucked in a drop of water still perfect , that could be a good choice for you
Dave -
Colin don’t waste your money on a Chinese router yes they look good on paper but you have little or no back up if it gives problems which it will hard it lift the phone for advice i know i bought a laser engraver from china and has give a few troubles lucky i could fix it myself stay away from the axyz routers i heard you bought one and you have said it gives troubles which I have heard before try and get a Tekcel as you may not know I have 3 routers now 2 of them are Tekcel and they are bullet proof workhorses whatever route you go make sure you get ball screw drives with servos and not rack and pinion shit like on the axyz which is 20 years out of date also stay away form stepper motors which is also old tech. Only problem is ball screws and servo motors cost more but they are far more efficience in movement and accuratery
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3mm on a 6mm shank single flute upward spiral solid carbide is the correct tool for all types of general signage especially for acrylic cuts like butter if used with correct feed and speeds, 2 flutes are crap for acrylic take it from me I have 20 years machining under my belt the problem with 2 flutes is there is not enough clearance between flutes and can cause heat buildup ok for some applications but in general I don’t use them and I pride myself on edge quality just ask Ian I have done work for him before , 6mm also same upward spiral good for 10mm and thicker material generally use it for 19mm , downward spiral has 2 applications best used for cutting woods this forces the material down onto the surface instead of lifting it up like an upward spiral brilliant for veneers ,hardwoods and plywood , also can be used in help pin down the component to table surface but this I would not recommend as it gives a good top edge it can force out material on the bottom edge ,
If you need advice on a specific material let me know I have machined basically every material you can think off
Hope this helps a bit could talk about tooling for hours
dave -
Martin each process has it good and bad point etching is probably the nicest finish on the stainless steel but it is limited to the size of plaque you can use most etching machines can only handle up yo 600mm wide , laser engraving uses a ceramic paste to bake on the graphic good for fine detail but can be scathed of with very heavy rubbing, mechanical engraving either on router on engraving machine is a slow process and you need to pay attention to tool wear especially on stainless but on a router bed you can engrave full sheets which I have done quite a few times both etching and engraving leave a Chanel where you apply paint to highlight the text or logo which is always better than laser marking
Again I could go on if you need mor help let me know been doing this for 15 years
Sorry Should have said any vector file is fine best is A.I file as it is normally smaller file size compared to EPS try and stay away from autocad files like Dxf and Dwg as they can give headaches when importing
Cheers dave -
Martin each process has it good and bad point etching is probably the nicest finish on the stainless steel but it is limited to the size of plaque you can use most etching machines can only handle up yo 600mm wide , laser engraving uses a ceramic paste to bake on the graphic good for fine detail but can be scathed of with very heavy rubbing, mechanical engraving either on router on engraving machine is a slow process and you need to pay attention to tool wear especially on stainless but on a router bed you can engrave full sheets which I have done quite a few times both etching and engraving leave a Chanel where you apply paint to highlight the text or logo which is always better than laser marking
Again I could go on if you need mor help let me know been doing this for 15 years
Cheers dave -
Hi Daniel are you still looking for advice on a router if so give me a call I can help you with this just too much to list here I have 3 Cnc routers one at 5m x2.5m with 9 spindles which I rebuilt myself another one at 3m x2m and an 8×4
Been using and fixing routers the last 16 years so know plenty about them
Dave -
The best tool. Suppliers are ITC as someone as mentioned already speak with Sally
She is very nice I have been dealing with her for years get yourself 6mm dia , single flute upwards spiral cutter, they are a great tool for PVC stick to the 19mm cut length as the 25mm cut length is too long and can break quite easily, there are more manufactures I have used all of them but ITC tools are the best a bit dearer than the rest but you pay for what you get
Hope this helps dave -
I have read all the comments and I thought i would add my 2 cents worth
The problem is stress cracking and there are a number of things that can cause it , first thing is to check if the material is cast or extruded, cast acrylic is twice as good as extruded personally I don’t buy or supply people anything else than cast. Next thing is to make sure you buy a good brand of acrylic, ICI Perspex and Autlglss are the top 2
Manufactures , you be surprised at the different manufactures qualities , when you flame polish acrylic you are stressing the edge of the acrylic you are meant to anneal the acrylic after polishing this to relive the stress that was introduced when polishing but very few people have an acrylic oven in which they can do this, the main thing is do not use meths it does work on good branded acrylic but it will crack the edge on poor quality
Use warm soapy water to clean or apply graphics white spirits does work well but can leave a mist on the acrylic so this should be used in extreme cases but I have used it myself and works ok for problem areas , laser cutting is just the same as flame polishing add all the same problems I know I have a laser machine which is used for acrylic stick to water and you will have no problems, sorry could talk about this a lot more been there seen it all done must of it
Any more advice let me know contact me directly dave -
This type of lettering is called prismatic cut any good routing software will have a command within it to machine this style of letter, we use artcam for all our machining
These letters are best used in 19mm PVC as it will last longer in an outdoor application mdf is a cheaper material and will work outside but it needs alot more sealing to stop water getting into it one thing I would say is this type of letter works best on a narrow stoke fonts like arial etc the reason for this is the software works from the widest point off the letter that means the widest point is the highest and the narrowest point of the letter is the smallest point this can leave the letter very weak when handling
Could talk about this for a while if any one needs more advice let me know
I have made thousands of these letters also made letters with bevels and recess
Cheers dave