Author Topic: Anybody build Dan Gelbart angled laser centre finder?  (Read 77130 times)

Offline vtsteam

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #150 on: May 13, 2015, 07:44:06 AM »
I spread it on the surface plate with a brayer, no thinner if new, maybe a drop if it's getting too thick. Works for me.

Dykem Hi-Spot worked slightly better than Prussian blue artst's oils because a little more intense and non drying. But the old tube had a white painted outside, and bits of this flaked off and drove me nuts wrecking rubs until I masking taped over the tube.
I love it when a Plan B comes together!
Steve
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Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #151 on: May 16, 2015, 03:16:46 PM »
I'm beating this thread to death......

Anyway, I'll be sanding and painting living room roof. Swinging beltsander overhead is brutal for officeat. Then I'll remove carpet and grind concrete flat before laying hardwood floor. Should keep me busy week or two.

I tested a little pin hole...I pricked a little pinhole on black carboard, cut it round and fited between spring and lense. It worked pretty good.

I removed tha sticker and found out that rear end screws off fairly rapidly revealing the contol board. I wonder if the control board could be mounted remotely or turned 90 degrees to make the whole thing shorter. Looks like a simple regulator, wonder if it needs to be immediately next to laser diode, or could it be moved a little further.

Pekka

Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #152 on: May 17, 2015, 02:13:27 AM »
Damn it. Frgot to add the pictures :bang:


Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #153 on: May 17, 2015, 08:05:00 AM »
I think I've decided to go with these bits. I don't believe I'll need a filter but I will use a small aperture plate to improve the dot shape.



Just need some spare time now to put it together.

Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #154 on: May 17, 2015, 12:10:54 PM »
Looks good.

How are you going to hook up the battery? Do you have parts for battery holder?

Are you going to build adjustable mount for the laser or use fixed angle?

I'm starting ti think this as an accessory to centrefinder.

Pekka

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #155 on: May 17, 2015, 03:24:48 PM »
The angle will be adjustable.

I expect to make the parts for the battery but if it's problematic commercial holders seem to be available for most batteries. All it needs is a hole for the battery, a couple of contacts and a spring.

I made a small "can" out of aluminium with a .65mm hole in the end for the Laser today.

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #156 on: May 31, 2015, 02:34:47 PM »

Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #157 on: June 01, 2015, 12:45:21 AM »
HDPE? You really didn't want laser body to make electrical contact on anything?

Looks nice. All parts in and then you'll find static balance?

How is the dot?

Pekka

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #158 on: June 01, 2015, 04:11:21 AM »
Just playing around with some ideas really. Dot seems pretty good. I didn't have any alloy the right size for the main body so it's some grey PVC I had. The laser mount is Ertalyte TX. Just thinking about how to mount the battery.

Update:

A quick lash up to see what results I get!



1400 rpm and the battery didn't come off! The laser housing has a taped hole for locking it in place but as its a nice friction fit it doesn't have a bolt in it yet but no movement on this either.



Looks good, I just need to work out the battery housing and check for balance.




« Last Edit: June 01, 2015, 02:28:52 PM by Arbalist »

Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #159 on: June 02, 2015, 02:39:26 PM »
Looks the part!

Have you tried yet how does the laser "paints" the edge of the boss, hole, or clylinder (pin). I have been thinking that that angle adjustment is not essential, but it's definately a conveniece. Reduces a lot of jacking the mill knee up and down.

Pekka

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #160 on: June 02, 2015, 04:18:41 PM »
I won't be testing operation until I've finished the unit. Shouldn't be too much longer hopefully.

Offline appletree

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #161 on: June 02, 2015, 06:25:17 PM »
Off slightly to one side Sainsburys are doing some "garden" solar lights at a 1 one of ours was faulty and was going to throw it away as its 20 miles to Sainsburys, any way the Mrs opened it up and a wire had come off. But the bit i am getting to it contains a 1.2 volt 2/3 AA rechargeable  battery (about 25mm long), could be useful
 

Offline PekkaNF

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #162 on: June 03, 2015, 01:08:05 AM »
Yesterday Postman Pat brought bunch of focusable small lasers, a lot like above. BUT exceptionally it had paper with it and at first look it looked like it says TTL????? 45s ON, 15s OFF...

I resumed ripping floor carper away and sanding the concrete floor----I'll have a look on it again when after I have leveled the floor.


Pekka

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #163 on: June 04, 2015, 06:51:23 PM »
The one I used was on for at least 4 or 5 mins whilst I fiddled about taking pictures and still seems ok. I expect in use it only needs to be on for a minute or two. If you do burn one out by leaving it on you'll remember next time and they don't cost very much.

Offline vtsteam

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #164 on: June 04, 2015, 09:07:42 PM »
Seems odd, why would a laser pointer have a duty cycle of seconds? In their original purpose, 45 seconds seems rather short.
I love it when a Plan B comes together!
Steve
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Offline BillTodd

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #165 on: July 05, 2015, 09:48:23 AM »
My version :-)

Based on Mike's (of Mikesworkshop) design , I've pared this down to the minimum using a plastic body and automatic centrifugal switch.


Photo 2 - The cap is  sized and shaped to clip into the 21mm battery recess

Photo 3 - the cheap 50p eBay laser module has the wires removed and a 40mm piece of tinned copper wire added to the negative (resister) terminal - the module's PCB has to be trimmed (grinder) to make sure the module will press nicely into the 6mm hole

4 & 5 - Once the module is pushed home the wire can be bent around to form the Negative battery connection.  A small piece of plastic foam packing is used to push the 3V lithium cell  away from the laser body (the +ve connection).

6 - Once the thing is rotating above a couple of hundred rpm , the battery is pushed against the body of the laser module and it lights up.

« Last Edit: July 05, 2015, 01:23:03 PM by BillTodd »
Bill

Offline drmico60

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #166 on: July 05, 2015, 10:23:27 AM »
Bill, Very nice
Mike

Offline BillTodd

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #167 on: July 11, 2015, 06:37:38 AM »
Thanks Mike :-)

This is the simplest one I can think of:

The rod is turned down to weaken it and then bent . It is then pressed into the head using a barbed form on the end of the rod.(previous version was threaded)

If you need a larger circle,  it is a simple matter to twist the head slightly.

The small offset weight does not upset my mill/drill.

« Last Edit: July 11, 2015, 08:06:43 AM by BillTodd »
Bill

Offline BillTodd

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #168 on: July 12, 2015, 10:17:09 AM »
Finally; one that works like Dan Gelbarts' and mounts to the ER32 chuck nut. Using an offcut of Nylon 6 bored to be a press fit .

Incidently, adding an iris as mentioned in the posts above (e.g. something with a small hole between the spring and laser diode) improves the functionality immensely.

I used one hole from a piece of Vero board (matrix PCB ) filed to fit into the laser recess.

Bill

Offline Arbalist

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Re: Anybody build Dan Gelbart angled laser centre finder?
« Reply #169 on: July 12, 2015, 10:46:33 AM »
Yes, using a small aperture does seem to work well. I turned a small aluminium housing for the laser and drilled a .65 mm hole in the bottom. It's the little silver canister to the left of the laser in this picture.



Still not got round to housing the battery properly as I've had other stuff to do but I have used it as is and it works very well.