What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Should W-00017 be countersunk or dimpled?

tims88

Well Known Member
I'm installing the RV-14 style leading edge light kit that Van's sells for the 10 in my RV-10 leading edges. I just got to the step last night where the OP-52 plans say to countersink W-00017 to fit a dimpled .025 skin. I countersunk a few of them before I noticed that the countersink was going all the way through the part very slightly. Have other people countersunk or dimpled these holes? Do I need to put a backer plate behind the holes since the countersink went all the way through or should I not worry about it since it's just a mount for a light?

EVGkP7yvPD_gYUheJYn_q44Jh59udvOe8rMEcqgTQn41-cS882W-WpSoqSlAcGbvM6KG-Mv84fSF88yk5HbZtEPwL38uP64VGvO41tSOTb2y6Nlkzp6F3p3q35yJc2z0XCfeCA6UzYhM6jyx1nwedSZKg9mNks-UrQWCmUxkYIiF06bdcInOPoW1wOFp8vskWDgs0TuD7OIC5HHs_ER3G4OwVmBXnZCER9YVkAonKe4tpQK0jcXs9zIlCYBottqs-usIQPDwb1fEuDJ-rXKEn96ubT904jHwR27kIngJIxMYvIygZ18da1wJPI8Pwt8YuG7PgUNCeMkS1QCJLMtW5SbMWU2PuVX1_146Pu6P1Irs_3vSy4uOt-LzWsaPuAXq_Cm66KN-QgMQScr1mbrqKCvU8LTqLicY9vrKnrCyPAgKXhS5ONi70B6E0wPWOeuN3iYLnEKz76zrh9YCXdbQ9LEH8CHjbgLolq_3iwoG78PAw5W5Pxkv6m0GKG3w9q_3TwpWAS6nnrMjCRGWrkrhxcxV1EDxVtR5kWolFjO5-cVf1tcVbXq71Ri39r8J-EGq03jHAVKO8ByGrZQUIHnD7Dk3fnLPdqqCvWtmpsnDyicU4Pi8pXJ8l-LLqx6klW55tt3dgu8jAw23_y3XDuE8JVRnXYKvasapPs1SJvxUi076OVqijDkj_N5Q3UqScAr8WqnYpledfoeY1Hmw8_u3VEeg5fofKyzNrh7GCR6mWWHnLOfvOw=w537-h371-no
 
I always put a backer plate behind thin parts because the countersink tool drifts if I don?t. I have an angle and a bar with various holes for this.
 
Dimple

Hi Tim,

The RV-14 instructions state to dimple those holes.

Regards,
Alex
 
I found myself dimpling in places where CS was called out: if my tools could do it I liked dimpling better. sometimes affects rivet call outs of course.
 
I always put a backer plate behind thin parts because the countersink tool drifts if I don’t.

I've had the problem before too but luckily the tool didn't drift this time.

The RV-14 instructions state to dimple those holes.

Thanks Alex, that's what I figured. I wish I knew that before I started countersinking the parts. Oh well, I think I'll just match drill a backer plate to support the holes I've already countersunk.

I found myself dimpling in places where CS was called out: if my tools could do it I liked dimpling better. sometimes affects rivet call outs of course.

Yeah I would have preferred to dimple all of them in this case but I didn't think about it until after I started countersinking.

Thanks for the replies everyone.
 
For this part and it's purpose I would think C/S holes would be fine especially if the plans call for it. I'd call Van's unless its just obviously looking wrong to you.
 
I always put a backer plate behind thin parts because the countersink tool drifts if I don?t. I have an angle and a bar with various holes for this.


If you take a scrap piece of thicker material that the nipple of the countersink can fit into clamp the two parts together then the countersink will not wander.
 
Countersinking thin sheet

Proper countersinking technique is performed in sheet thick enough to leave a "barrel". Knife edge at the bottom of the hole is a no-no.

My AV and SnF forum and reference materials are currently stored, but IIRC minimum material thickness for counter sinking is .040
 
Section 5 in the construction manual has a lot of details regarding Van's standards for machine countersinking.
 
I would use a backing plate when countersinking. I would not add a backing plate to reinforce a less than perfect countersunk hole for this application.
 
Back
Top