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Lazy Susan bearing mod for Dob bases.


Daz Type-R

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Hi.

Here is a break down and pics (hopefully) of what I did to mod my dob base.

This is based on my dob base, I do not know if other dob bases differ in size (I`m assuming they do) so you need to take that into account if modding yours.

First thing first, below is a shopping list of things you need.....

1. http://simplybearing....ducts_id=42341 - This is the 12 inch lazy susan bearing, I went for the 12 inch just to help with weight distribution but to be honest any size will do. This cost a total of £20.22 which was including Royal Mail 1st class delivery and VAT. Fantastic service - ordered at 12:30 on a Monday lunch, arrived at work 9:30 the next morning. 2-3 minutes to set up an account.

2. I found these on Amazon, do a search for slide guides, I used the 1" version (DO NOT use the 2" version), these set me back £6.97, service was okay, took 3 days to arrive. I believe you can also get these from B&Q or similar places.

3. Plastic milk bottles - you should need no more than 2. I used the 2 ltr bottles.

4. Screw drivers, pencil, ruler and screws (screws need to fit the holes in the lazy susan bearing and be no bigger then 15-18 mm in length)

So the first thing I did was take the dob base apart, so that you just have the bottom base in front of you. Next, draw a square round the centre hole in your base plate making sure the sides of the square are as close to the centre hole as you can get. (see Fig 1)

 

fig1_zps32d5280a.jpg

Next draw 2 straight lines going through each corner of the square right to the very edge of your base plate, so now you have basically divided your base into quarters.

Next line the 4 mounting holes on your lazy susan bearing up with the 4 lines you have just drawn. Once all 4 mounting holes have a line through the middle of them then your bearing is correctly in place and in the exact centre. Now screw it down. (see Fig 2 & 3)

 

fig2_zps1ab17d19.jpg

 

fig3_zps9d2b696f.jpg

The next step is to now add your slide guides (see Fig 4) (if even needed).

 

fig4_zpsc301f722.jpg

 

You may be happy with the level of glide provided by the bearing. If not, now line your slide guides up along the 4 lines you have previously drawn. You need to place these as close to the edge as you can. If not, then they will catch on the mount part of your base (the part that holds the scope) stopping the mount from turning. Your base should now look something like Fig 5.

 

fig5_zps479a8769.jpg

You may find that the slide guides do not even touch the top part of the base, if so use your plastic milk cartons to make washers and stack them up under the slide guides screwing them down until the slide guides just touch the top part of the base. (see Fig 6, 7 & ?

 

fig6_zps84cb20aa.jpg

 

fig7_zps4c415c6a.jpg

 

fig8_zpsa382bd13.jpg

Thats it. You may have to keep building and and taking to bits your base until you achieve the correct level of resistance provided by the plastic milk washers but it is worth it in the end.

One other thing to look out for, if you build the height of your base up too much, you may need to replace the centre bolt that keeps it all together. You just need the same thickness of bolt, just another inch or so longer.

Hope this is enough info for you and you find the guide helpfull.

Regards,

Daz.

Edited by Daz Type-R
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  • 7 months later...
Guest wisewoman

Yes thanks for that, I had heard about this mysterious 'milk bottle bearing' trick. :) I've been using copious amount of wax polish on my dob monster.

Melissa

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  • 1 year later...

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