can someone please help with hole dimensions

[reefy86]

Hi could someone please tell me the correct settings in solidworks for this linear profile rail. its telling me on the diagram that the bolt size is 4.5mm but when using hole wizard im struggling to find the right settings for a tapped hole. or if i just use standard holes and setting dimensions im only seeing radius so do i just half that so if my hole is 4.5mm i enter 2.25mm in the radius dialog?

cheers

Ash

[komatias]

Hi could someone please tell me the correct settings in solidworks for this linear profile rail. its telling me on the diagram that the bolt size is 4.5mm but when using hole wizard im struggling to find the right settings for a tapped hole. or if i just use standard holes and setting dimensions im only seeing radius so do i just half that so if my hole is 4.5mm i enter 2.25mm in the radius dialog?

cheers

Ash

The rails have larger than normal clearance holes to allow them to be adjusted as needed. If your rails have 4.5mm holes and they are screwed in from the top, you will need to make M4 tapped holes. The pilot hole for a tapped M4 using a cutting tap, as opposed to a rolling one, is 3.3mm.

The pilot holes are always=nominal diameter-1 pitch length. So an M6 will have a 5mm pilot, a M5 uses a 4.2mm pilot etc.

[reefy86]

thank you very much :)

[reefy86]

so just to double check. if i make holes in my drawing thats 4.5mm and send that drawing of to be drilled will they tap my holes at 4.5mm or will they just do a basic straight hole at 4.5mm?

cheers

Ash

[komatias]

depends if you send them a drawing or a solid model. As a rule, you should not send a solid model without a drawing to ensure your intentions are met. For example, a solid model may not convey tolernaces.

A 4.5mm hole is just that. Unless you tell them to tap it to an M4, you will not get at tapped hole. Also worth noting that if you can accept a drilled hole, make a note that the drill point is acceptable. Flat bottomed holes are marginally more expensive.

[reefy86]

thing is though that really confuses me is when looking at the dimensions from zapp it just shows a diagram with an hole at 4.5mm, im not good at knowing what holes what but in solidwork i select m4 and it has a default settings at 10.10mm blind hole depth and 8.00mm tap thread depth.

[reefy86]

im not using the hole wizzard btw im just using a standard 4.5mm circle with an extruded cut.

cheers

Ash