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The Yorkshireman
07-24-2017, 11:24 AM
Hello
I've tried posting this in the UDS thread but had no reply. I'm currently building my first UDS. I've gone for the three intake design with one ball valve (the valve being on one of the three intakes). I've got two 1/2 inch unions from work and one 15mm ball valve, I believe 15mm is 1/2inch. Internal diameter. I've realised everyone is using 3/4 inch now I've gone and drilled the holes! Will I have issue with getting up to temperature using this smaller size or will I be ok using 1/2inch instead of 3/4?
Thank you in advance.

RT
07-24-2017, 11:57 AM
It should come up to temperature it will just be slower.

Nuco59
07-24-2017, 01:08 PM
You could always drill the holes larger- you just can't drill them smaller :grin:

if you need to come up faster- just add one more 1/2" nipple.

You can use what you have - you may have to keep one of your 2 "unions"?" open and use your ball valve to throttle control temp. ex.. I cap my two (3/4") nipples as my temp comes up - I adjust the open 3/4" ball valve to get my final temp - usually 275- 300 F.

does that make sense?

The Yorkshireman
07-24-2017, 03:00 PM
Thanks for the speedy replies. Oh yeah I mean nipples! Lol. I'll give it a test run with the 1/2 and see if I can get up to temp. If it doesn't work, worse case I'll have to buy a cone drill bit and enlarge them to 3/4. Than buy new parts, this will hurt the most. Nuco59 how much do you close your 3/4 ball valve normally?

DouG M
07-24-2017, 05:23 PM
Yes I use 3/4 " intakes. BUT after it is up to temp. I use only just the ball valve. Use your 1/2 " and if you have to open one or two of those inlets and regulate with the valve great. It's a trial and adjust to correct. On your trial runs use low cost food and no time lines. PS my open holes I only use magnets to open or close - adjust.

4ever3
07-24-2017, 06:01 PM
You could always start a little hotter (light more coals) to get it up to temp quicker.

I have 3 3/4" holes and start with all of them open till I get to 250° then close 1. When I get to 275° I close the 2nd one and at the same time close the 3rd one to half and she settles in at 300°, right where I want her.

You'll more than likely have to cook with one wide open but you'll figure it out.