-
18-02-2016 #21
-
Well then you have not said on the drawing which side is being countersunk. You have not mentioned 8.4mm only 8.1mm. If you say you want a hole for M8 it will probably end up at 6.8MM
So
1: Do you need 30mm ali
2: You don't need to say M8 just the hole size you want and whether it is through hole or to a depth
3: set all your measurements from two datum's ie bottom and one side...Clive
The more you know, The better you know, How little you know
-
18-02-2016 #23
thanks guys, 30mm probably is ott what would you recommend for all round? i think i will stay with 30mm on the front z axis plate though but for everything else would 25 do? i know 20 is the minimum.
and with the holes so i just say 8.4mm through on plate 1 and 6.8mm tapped 15mm depth on plate 2?
Ash
-
How big is this machine I would have thought 20mm would have been enough for gantry ends and Z axis.
You said you wanted 8.1mm so now you are saying 8.4 !!!.
You have not mentioned plate number 2 If you want them to tap the holes just say tapped for M8 x 1.25 if that is what you want. You can't just say 6.8mm tapped
I would suggest you re do the posted drawing with the measurements as shown etc..Clive
The more you know, The better you know, How little you know
-
18-02-2016 #25
above post mentioned tolerance stackup issue with tighter holes which is why i went back to 8.4mm. plate 2 was me trying to say i want a m8 cap screw to go through plate 1 and then screwed into plate 2 which is tapped ect. i apologise for my bad explinations. and machine cutting area is 8 x 4.
cheers
Ash
-
..Clive
The more you know, The better you know, How little you know
-
18-02-2016 #27
just a quick one. if im using shoulder screws do i do the through holes 10mm which is what the shoulder screw is or do i make it slightly bigger like 10.1mm. dont want to make a mistake of inserting 10mm shoulder into 10mm hole and it gets stuck ect
-
19-02-2016 #28
Ok, shoulder bolts are ground to specific tolerances on the shank. Depending where you get them from, there will be a tolerance class to them like h8 or something. That will tell you what hole size and tolerance you should specify depending on the tightness of the fit you want. Give us a link to the bolts.
This is where geometric tolerance will also come in to play but that may be overkill for your application.
Are you looking to get this made by a chap in a shed or are a pro machine shop?https://emvioeng.com
Machine tools and 3D printing supplies. Expanding constantly.
-
19-02-2016 #29
just in general i was checking ebay out for the shoulder screws
http://www.ebay.co.uk/itm/10mm-M8-SO...DKYqt_xV0EeV8A
states nothing about tolerance just simple dimensions ect. although here it has more technical info but £3.44 per screw jesus lol.
http://www.shoulder-screws.co.uk/?gc...LnEaAskt8P8HAQLast edited by reefy86; 19-02-2016 at 01:56 PM.
-
19-02-2016 #30
Thread Information
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
Similar Threads
-
CNC machine cutting incorrect dimensions
By Clem in forum Machine DiscussionReplies: 13Last Post: 26-02-2014, 10:00 PM -
denford orac tail stock dimensions
By dazza in forum Lathes, Lathe Rebuilding & ConversionsReplies: 3Last Post: 24-11-2013, 10:42 PM -
Cross sectional dimensions for CAD drawings
By Husky in forum Gantry/Router Machines & BuildingReplies: 5Last Post: 24-02-2013, 06:19 PM -
BK12 Hole Spacing Dimensions On Top
By Hobgoblin in forum Lead Screws, Nuts & SupportsReplies: 2Last Post: 21-09-2012, 10:31 PM -
Dimensions and Weight of Denford Starmill PC Please
By cristec in forum Milling Machines, Builds & ConversionsReplies: 4Last Post: 13-08-2012, 07:02 AM
Bookmarks